Fidelity of individual animals to breeding sites is a primary determinant of population structure. The degree and scale of philopatry in a population reflect the fitness effects of social facilitation, ecological adaptation and optimal inbreeding. Patterns of breeding-site movement and fidelity are functions of social structure and are frequently sex biased. We report on a female humpback whale (Megaptera novaeangliae) first identified by natural markings off Brazil that subsequently was photographed off Madagascar. The minimum travel distance between these locations is greater than 9800 km, approximately 4000 km longer than any previously reported movement between breeding grounds, more than twice the species' typical seasonal migratory distance and the longest documented movement by a mammal. It is unexpected to find this exceptional long-distance movement between breeding groups by a female, as models of philopatry suggest that male mammals move more frequently or over longer distances in search of mating opportunities. While such movement may be advantageous, especially in changeable or unpredictable circumstances, it is not possible to unambiguously ascribe causality to this rare observation. This finding illustrates the behavioural flexibility in movement patterns that may be demonstrated within a typically philopatric species.

Stevick PT||Neves MC||Johansen F||Engel MH||Allen J||Marcondes MC||Carlson C

Biology letters

Journal Article||Research Support, Non-U.S. Gov't

https://pubmed.ncbi.nlm.nih.gov/20943678/

Humpback whales migrate between relatively unproductive tropical or temperate breeding grounds and productive high latitude feeding areas. However, not all individuals of a population undertake the annual migration to the breeding grounds; instead some are thought to remain on the feeding grounds year-round, presumably to avoid the energetic demands of migration. In the Southern Hemisphere, ice and inclement weather conditions restrict investigations of humpback whale presence on feeding grounds as well as the extent of their southern range. Two years of near-continuous recordings from the PerenniAL Acoustic Observatory in the Antarctic Ocean (PALAOA, Ekstrom Iceshelf, 70 degrees 31'S, 8 degrees 13'W) are used to explore the acoustic presence of humpback whales in an Antarctic coastal area. Humpback whale calls were present during nine and eleven months of 2008 and 2009, respectively. In 2008, calls were present in January through April, June through August, November and December, whereas in 2009, calls were present throughout the year, except in September. Calls occurred in un-patterned sequences, representing non-song sound production. Typically, calls occurred in bouts, ranging from 2 to 42 consecutive days with February, March and April having the highest daily occurrence of calls in 2008. In 2009, February, March, April and May had the highest daily occurrence of calls. Whales were estimated to be within a 100 km radius off PALAOA. Calls were also present during austral winter when ice cover within this radius was >90%. These results demonstrate that coastal areas near the Antarctic continent are likely of greater importance to humpback whales than previously assumed, presumably providing food resources year-round and open water in winter where animals can breathe.

Journal Article||Research Support, Non-U.S. Gov't

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0073007

Oceáno Austral(Observatorio Acústico Perennial en el Océano Antártico (PALAOA))

It has been known for some time that humpback whales (Megaptera novaeangliae) occur in waters of the Galápagos Islands, an oceanic archipelago located 1,000km west of Ecuador, South America (1°S, 91 °W), but their presence there has been poorly documented. Although presumed, no linkage has been established between Galápagos and southeast Pacific humpback whales (Breeding Stock G), the nearest breeding stock. An expedition to Galápagos was carried out between 31 August and 10 September 2005 to document the presence of humpback whales, their distribution, and their relationship to other stocks in the Pacific. Surveys covered 722km of the central and southern parts of the archipelago. Only one adult with a newborn calf was found at Santa Fe Island (0°47'S, 90°05.1 'W), yielding an encounter rate of 0.27 whales per 100km of survey. A hydrophone with a response frequency range of 0.25-25kHz was dropped 25 times, but no whale sounds were heard. A skin sample was obtained by darting of the adult at Santa Fé, and was used for genetic analysis of the mtDNA control region. The haplotype of the Galápagos specimen has been found in a few individuals sampled previously off Colombia, Ecuador and the Antarctic Peninsula, thus establishing at least some degree of relatedness with Breeding Stock G. The observations, combined with a compilation of historical and recent sighting information in the archipelago, support the idea that Galápagos is a breeding area for the species. Further studies are needed to establish the level of discreteness, size and other basic aspects of the Galápagos humpback whale population.

Journal of Cetacean Research and Management

https://www.scopus.com/inward/record.uri?eid=2-s2.0-84865345251&partnerID=40&md5=cae6c45e1cfbde349a53cfeae9cdf441

Monitoring whales in remote areas is important for their conservation; however, using traditional survey platforms (boat and plane) in such regions is logistically difficult. The use of very high-resolution satellite imagery to survey whales, particularly in remote locations, is gaining interest and momentum. However, the development of this emerging technology relies on accurate automated systems to detect whales, which are currently lacking. Such detection systems require access to an open source library containing examples of whales annotated in satellite images to train and test automatic detection systems. Here we present a dataset of 633 annotated whale objects, created by surveying 6,300 km2 of satellite imagery captured by various very high-resolution satellites (i.e. WorldView-3, WorldView-2, GeoEye-1 and Quickbird-2) in various regions across the globe (e.g. Argentina, New Zealand, South Africa, United States, Mexico). The dataset covers four different species: southern right whale (Eubalaena glacialis), humpback whale (Megaptera novaeangliae), fin whale (Balaenoptera physalus), and grey whale (Eschrichtius robustus).

Scientific data

2022 May 27

Dataset||Journal Article||Research Support, Non-U.S. Gov't

https://pubmed.ncbi.nlm.nih.gov/35624202/

Understanding the patterns of spatial and temporal distribution in threshold habitats of highly migratory and endangered species is important for understanding their habitat requirements and recovery trends. Herein, we present new data about the distribution of humpback whales (Megaptera novaeangliae) in neritic waters off the northern coast of Peru: an area that constitutes a transitional path from cold, upwelling waters to warm equatorial waters where the breeding habitat is located. Data was collected during four consecutive austral winter/spring seasons from 2010 to 2013, using whale-watching boats as platforms for research. A total of 1048 whales distributed between 487 groups were sighted. The spatial distribution of humpbacks resembled the characteristic segregation of whale groups according to their size/age class and social context in breeding habitats; mother and calf pairs were present in very shallow waters close to the coast, while dyads, trios or more whales were widely distributed from shallow to moderate depths over the continental shelf break. Sea surface temperatures (range: 18.2-25.9 degrees C) in coastal waters were slightly colder than those closer to the oceanic realm, likely due to the influence of cold upwelled waters from the Humboldt Current system. Our results provide new evidence of the southward extension of the breeding region of humpback whales in the Southeast Pacific. Integrating this information with the knowledge from the rest of the breeding region and foraging grounds would enhance our current understanding of population dynamics and recovery trends of this species.

Journal Article||Research Support, Non-U.S. Gov't

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0112627

Temperatura del mar, profundida del óceano, distancia de la costa

De (4°10´38.23"S, 81°8.27´4.83"W) a (4°15´1.36"S, 81°13´50,17"W)

At the breeding grounds of most baleen whales the patchiness and gaps in spatial distribution results from interactions between behavior patterns and environmental conditions. We evaluated the influence of environmental factors (bathymetry and distance from shore with quadratic terms, and wind speed), effort, and spatial autocorrelation effects to predict humpback whale group density in the Southwest Atlantic Ocean. Count data of groups by grid cells were fitted with conditional autoregressive models (CAR). Bayesian inference was performed via integrated nested Laplace approximation. The best-fit model contained distance from shore and its quadratic term, bathymetry, and the autoregressive component. Occupancy probability was high for the Abrolhos Bank, some cells from the northeast continental shelf and southeast margin, but gaps in occurrence were identified. High densities were estimated in the east continental margin, with the highest density in the Abrolhos Bank, in some cells of the northeast continental margin and in the southernmost area. We report that intermediate distances from the coast, and shallow waters were preferred for breeding and calving activities. We suggest that CAR models may incorporate aggregation mechanisms into habitat modeling and may provide advances in marine mammal analyses by accounting for residual autocorrelation. © 2018 Society for Marine Mammalogy

Marine Mammal Science

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85051293689&doi=10.1111%2fmms.12492&partnerID=40&md5=4b37a658d209dbc207b77e0704286ad3

Modelo autoregresivos espaciales

Modelo Autoregresivo Espacial

Distancia a la cosa, Batimetría, Esfuerzo de muestreo, Componente autoregresivos

We developed a Bayesian distance sampling analysis using a hierarchically structured model parameterization to estimate humpback whale abundance in the Southwest Atlantic Ocean (Breeding Stock A). We included covariates that affect detection (altitude and sighting cue) and occurrence probability (year and distance from shore). Population sizes for 2008, 2011 and 2015 were estimated to be 7,689 (P.I.95% = 6585–8931), 8652 (P.I.95% = 7696–9682), and 12,123 (P.I.95% = 10,811–13,531), respectively. The results indicate an aggregation of humpback whales in an intermediate distance from shoreline, an increasing in density from 2008 to 2001 and a substantial overlap between posterior distributions of density for 2011 and 2015, which suggests a stabilization of population growth over the last year. Our parameterization provided a clear view of observational and ecological processes and illustrates that the Bayesian hierarchical line transect approach provides a flexible tool to account for and evaluate various sources of uncertainty. © 2017 Elsevier B.V.

Ecological Modelling

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85019957018&doi=10.1016%2fj.ecolmodel.2017.05.003&partnerID=40&md5=a44edda08ac20303794bb37b8b3fe6bc

Modelo de línea de transecto, Bayesiano jerárquico

Detección, Ocurrencia, Abundancia

Humpback whales (Megaptera novaeangliae) annually undertake the longest migrations between seasonal feeding and breeding grounds of any mammal. Despite this dispersal potential, discontinuous seasonal distributions and migratory patterns suggest that humpbacks form discrete regional populations within each ocean. To better understand the worldwide population history of humpbacks, and the interplay of this species with the oceanic environment through geological time, we assembled mitochondrial DNA control region sequences representing approximately 2700 individuals (465 bp, 219 haplo-types) and eight nuclear intronic sequences representing approximately 70 individuals (3700 bp, 140 alleles) from the North Pacific, North Atlantic and Southern Hemisphere. Bayesian divergence time reconstructions date the origin of humpback mtDNA lineages to the Pleistocene (880 ka, 95% posterior intervals 550-1320 ka) and estimate radiation of current Northern Hemisphere lineages between 50 and 200 ka, indicating colonization of the northern oceans prior to the Last Glacial Maximum. Coalescent analyses reveal restricted gene flow between ocean basins, with long-term migration rates (individual migrants per generation) of less than 3.3 for mtDNA and less than 2 for nuclear genomic DNA. Genetic evidence suggests that humpbacks in the North Pacific, North Atlantic and Southern Hemisphere are on independent evolutionary trajectories, supporting taxonomic revision of M. novaeangliae to three subspecies. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Jackson J.A.; Steel D.J.; Beerli P.; Congdon B.C.; Olavarría C.; Leslie M.S.; Pomilla C.; Rosenbaum H.; Scott Baker C.

Proceedings of the Royal Society B: Biological Sciences

https://www.scopus.com/inward/record.uri?eid=2-s2.0-84922393337&doi=10.1098%2frspb.2013.3222&partnerID=40&md5=27573d02ad0481ad8cd19344edb53951

Tasa de mutación, Tiempo de divergencia, Flujo genético, Tamaño efectivo de la población

In animal social networks, a large acoustic communication space tends to involve complex networks. Signal masking may reduce this space, leading to detrimental effects on the animal's ability to obtain important social information. Humpback whales use acoustic social sounds (vocal sounds and surface-generated sounds from breaching or fin slapping) for within- and between-group communication. In this study, changes in various sound parameters (e.g., signal-above-noise and frequency content) of received humpback whale social sounds were statistically modeled against the combined effect of increasing wind-dominated noise and distance from the source (whale) to produce masking models. Behavioral data on vocalizing groups were also used to inform these models. The acoustic communication space, in this shallow water (<50 m) environment, extended to approximately 4 km from the signaler in median wind noise. However, the majority of behavioral interactions occurred within 2 km of the signaler. Surface-generated signals propagated better and likely function to maintain this space in higher wind noise. This study provides a basic wind-noise masking model for social communication signals in humpback whales which can be updated as more information on humpback auditory capabilities, and potential masking effects of anthropogenic noise sources, becomes available.

The Journal of the Acoustical Society of America

Journal Article||Research Support, U.S. Gov't, Non-P.H.S.

https://pubmed.ncbi.nlm.nih.gov/30180684/

Modelo de propagación acústica (BELLHOP)

Batimetría, Velocidad del sonido, Absorción del sonido, Frecuencia de la llamada, Intensidad de la llamada, Distancia entre la ballena y el recpetor

Ecuador(Isla Santa Cruz, Isla Isabela, Isla San Cristóbal)

Since 2000, an increasing number of humpback whale sightings have been recorded in northern Chilean Patagonia (mostly between 41.5°S and 44°S) from dedicated aerial and marine surveys and also opportunistic and land-based platforms during austral summer and autumn months. Based on local knowledge from the early years of coastal whaling suggesting the historic presence of humpback whales in the area, and more recent observations confirming feeding groups, mother-calf pairs, and philopatry, it is proposed that a proportion of the eastern South Pacific humpback whales consistently use the Chiloe-Corcovado region to feed and nurse their young. This mid-latitude area could be regarded as the northernmost feeding ground for humpback whales in South America, extending the previous known range some 1300km north. These findings provide further evidence for alternative life-strategies other than traditional migration and highlight the importance of northern Patagonian fjords to resolve questions that are central for large baleen whale conservation and management such as the extent and characteristics of spatio-temporal habitat use and overlap with human activities. The need for future research on the migratory movements and population structure of this poorly understood population of humpback whales is emphasized, while an account is given of the threats they currently face. © 2013 John Wiley & Sons, Ltd.

Hucke-Gaete R.; Haro D.; Torres-Florez J.P.; Montecinos Y.; Viddi F.; Bedriñana-Romano L.; Nery M.F.; Ruiz J.

Aquatic Conservation: Marine and Freshwater Ecosystems

https://www.scopus.com/inward/record.uri?eid=2-s2.0-84888863321&doi=10.1002%2faqc.2343&partnerID=40&md5=3b1e5ddcbd8f272011ee9c4c45421c73

Modelo de captura-recaptura de Petersen

Modelo de Captura -Recaptura de Petersen

Tamaño de la población, Numero de individuos en la primera muestra, Numero de inidivudos capturados en la segunda muestra, Numero de individuos recapturados en la segunda muestra}

Chile (Golfo de Corcovado, Seno de Reloncaví, Canal de Chacao)

The potential impact of increasing vessel traffic and coastal development has led to concerns regarding the future of the Brazilian humpback whale Megaptera novaeangliae population. Our objective was to monitor humpback whale abundance in the Brazilian coastal breeding grounds in order to provide information to support future conservation strategies for this species. To this end, a 4 yr series (2002 to 2005) of aerial surveys was implemented. Abundance was estimated using standard line-transect methods. Data were analyzed using the software DISTANCE 5.0. Perpendicular sighting data were modeled using (1) the uniform function with cosine and simple polynomial adjustments, (2) the half-normal function with cosine, and (3) the hazard-rate function with cosine and a simple polynomial series expansion. The model that best fitted the data was selected according to Akaike's Information Criterion (AIC). We estimated the population off the Brazilian coast to be 6404 (CV = 0.11) ind. in 2005. Alternative scenarios are presented to permit the discussion of results obtained from different g (0) corrections (where g (0) is the probability of detecting an animal at distance 0). We confirmed what previous studies have shown, i.e. that the studied population is increasing, and it is expected that new areas will be occupied and conflicts of interests will arise. The results of this study support the Brazilian government's stance against whaling and should be used in national and international debate to help solve conflicts of interest and to find non-lethal solutions. © Inter-Research 2010.

Endangered Species Research

https://www.scopus.com/inward/record.uri?eid=2-s2.0-79955013630&doi=10.3354%2fesr00282&partnerID=40&md5=ca0adc860afe78a642252c6d334fe23f

Modelo de captura y recaptura de Schnabel

Modelo de Captura y Recaptura de Schnabel

Tamaños Poblacional, Numero de individuos marcados en la primera ocasión, Numero de individuos capturados en la segunda ocasión, Numero de individuos recapturados en la segunda ocasión, Estimación del tamaño poblacional

Brasil(Bahía, Sergipe, Alagoas, Pernambuco y Paraíba)

Humpback whales (Megaptera novaeangliae) are a cosmopolitan species and perform long annual migrations between low-latitude breeding areas and high-latitude feeding areas. Their breeding populations appear to be spatially and genetically segregated due to long-term, maternally inherited fidelity to natal breeding areas. In the Southern Hemisphere, some humpback whale breeding populations mix in Southern Ocean waters in summer, but very little movement between Pacific and Atlantic waters has been identified to date, suggesting these waters constituted an oceanic boundary between genetically distinct populations. Here, we present new evidence of summer co-occurrence in the West Antarctic Peninsula feeding area of two recovering humpback whale breeding populations from the Atlantic (Brazil) and Pacific (Central and South America). As humpback whale populations recover, observations like this point to the need to revise our perceptions of boundaries between stocks, particularly on high latitude feeding grounds. We suggest that this "Southern Ocean Exchange" may become more frequent as populations recover from commercial whaling and climate change modifies environmental dynamics and humpback whale prey availability.

Marcondes MCC||Cheeseman T||Jackson JA||Friedlaender AS||Pallin L||Olio M||Wedekin LL||Daura-Jorge FG||Cardoso J||Santos JDF||Fortes RC||Araujo MF||Bassoi M||Beaver V||Bombosch A||Clark CW||Denkinger J||Boyle A||Rasmussen K||Savenko O||Avila IC||Palacios DM||Kennedy AS||Sousa-Lima RS

Scientific reports

Journal Article||Research Support, Non-U.S. Gov't

https://pubmed.ncbi.nlm.nih.gov/34880273/

Avistamientos y reavistamientos

Oceáno Austral(Península Antártica Occidental, Islas Shetland, Islas Orcadas del Sur)

Information on the genetic characterisation of humpback whales (Megaptera novaeangliae) wintering off Ecuador (Breeding Stock G) is presented. Mitochondrial DNA was extracted and sequenced from 230 skin samples collected between 2002 and 2008 to establish the genetic diversity of this population. From 182 usable samples, 41 different haplotypes were found, eight of which were new and unique. Haplotype diversity (h ± SD) was estimated to be 0.922 ±0.012 and the nucleotide diversity (π ± SD) 0.019 ± 0.009. A comparison with other areas within the Southeast Pacific (Colombia and Magellan Strait) and the Antarctic Peninsula suggested panmixia within Breeding Stock G, even though significant differentiation was found with Magellan Strait (p < 0.0001 in both FSTand ΦST). An additional analysis with the exact test of population differentiation showed significant differences in haplotype frequencies between breeding areas in Ecuador and southern Colombia (p <0.01), suggesting some level of stratification at breeding grounds as supported by photo-identification studies. The Ecuadorian dataset included haplotypes reported in all three Southern Hemisphere ocean basins indicating recent gene flow within the Southern Hemisphere. The population showed a male-biased sex ratio in adult animals of 2.16:1. Further research and a larger number of samples from breeding areas in the north (Panama and Costa Rica) are required to appropriately assess the extent of structure in this population.

Journal of Cetacean Research and Management

https://www.scopus.com/inward/record.uri?eid=2-s2.0-84869760182&partnerID=40&md5=e641b8515d7aa381ef3fbd3252fa7b56

Tasa de mutación del ADN, Tamaño de la población, Modelo de crecimiento, Tiempo de divergencia

The description of genetic population structure over a species' geographic range can provide insights into its evolutionary history and also support effective management efforts. Assessments for globally distributed species are rare, however, requiring significant international coordination and collaboration. The global distribution of demographically discrete populations for the humpback whale Megaptera novaeangliae is not fully known, hampering the definition of appropriate management units. Here, we present the first circumglobal assessment of mito - chondrial genetic population structure across the species' range in the Southern Hemisphere and Arabian Sea. We combine new and existing data from the mitochondrial (mt)DNA control region that resulted in a 311 bp consensus sequence of the mtDNA control region for 3009 individuals sampled across 14 breeding stocks and subpopulations currently recognized by the International Whaling Commission. We assess genetic diversity and test for genetic differentiation and also estimate the magnitude and directionality of historic matrilineal gene flow between putative populations. Our results indicate that maternally directed site fidelity drives significant genetic population structure between breeding stocks within ocean basins. However, patterns of connectivity differ across the circumpolar range, possibly as a result of differences in the extent of longitudinal movements on feeding areas. The number of population comparisons observed to be significantly differentiated were found to diminish at the subpopulation scale when nucleotide differences were examined, indicating that more complex processes underlie genetic structure at this scale. It is crucial that these complexities and uncertainties are afforded greater consideration in management and regulatory efforts. © The authors 2017.

Rosenbaum H.C.; Kershaw F.; Mendez M.; Pomilla C.; Leslie M.S.; Findlay K.P.; Best P.B.; Collins T.; Vely M.; Engel M.H.; Baldwin R.; Minton G.; Meÿer M.; Flórez-González L.; Poole M.M.; Hauser N.; Garrigue C.; Brasseur M.; Bannister J.; Anderson M.; Olavarría C.; Baker C.S.

Endangered Species Research

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85050966493&doi=10.3354%2fESR00822&partnerID=40&md5=9b7d5a667cf67c36cbe2184cf1b2b543

Modelo de coalescencia con migración

Modelo de Coalescencia con Migración

Tamaño efectivo de la población, Tasa de mutación, Tiempo de divergencia, Flujo génico

We investigated sex-related site fidelity by humpback whales to the Fueguian Archipelago, a new feeding area in the eastern South Pacific, by examining the resighting histories of 45 males and 39 females recorded from 2003 to 2012. Results indicated an overall annual return to the feeding area of 74.8%, and annual sex ratio is roughly equal in the population. The probability of an individual being resighted across years and in subsequent years was not significantly different for both males and females, however, the proportion of resighting within a year was significantly higher for individual males compared to females. Potential sources of sex-related bias were analyzed, but none were found to be significant. Greater intraannual resighting frequency for males may reflect sex-based differences in spatial occupation and short-range movements due to potential differences in energy budgets. © 2013 Society for Marine Mammalogy.

Marine Mammal Science

https://www.scopus.com/inward/record.uri?eid=2-s2.0-84897507387&doi=10.1111%2fmms.12048&partnerID=40&md5=b381ab781fd42dc63b4c9ec172a200d1

Modelo de Cormack Jolly-Seber

Supervivencia, Tasa de captura, Fidelidad del sitio

The rate of growth of any population is a quantity of interest in conservation and management and is constrained by biological factors. In this study, recent data on life-history parameters influencing rates of population growth in humpback whales, including survival, age at first parturition and calving rate are reviewed. Monte Carlo simulations are used to compute a distribution of rates of increase (ROIs) taking into account uncertainty in biological parameter estimates. Two approaches for computing juvenile survival are proposed, which taken into account along with other life-history data, resulted in the following estimates of the rate of population growth: Approach A: mean of 7.3%/year (95% CI = 3.5-10.5%/year) and Approach B: mean of 8.6%/year (95% CI = 5.0-11. 4%/year). It is proposed that the upper 99% quantile of the resulting distribution of the ROI for Approach B (11.8%/year) be established as the maximum plausible ROI for humpback whales and be used in population assessment of the species. Possible sources of positive and negative biases in the present estimates are presented and include measurement error in estimation of life-history parameters, changes in the environment within the period these quantities are measured, density dependence or other natural factors. However, it is difficult to evaluate potential biases without additional data. The methods presented in this study can be applied to other species for which life-history parameters are available and are useful in assessing plausibility in the estimation of population growth rates from time series of abundance estimates. © 2010 Springer-Verlag.

Marine Biology

https://www.scopus.com/inward/record.uri?eid=2-s2.0-77952428052&doi=10.1007%2fs00227-010-1403-y&partnerID=40&md5=2e585d5b446f3cc38b8150076aa77d24

Modelo de crecimiento Poblacional de matriz de Leslie

Modelo de Crecimiento Poblacional con Maztriz de Leslie

Supervivencia, Fertilidad, Edad de primera reproducción

The population of humpback whales (Megaptera novaeangliae) wintering off eastern South America was exploited by commercial whaling almost to the point of extinction in the mid-twentieth century. Since cessation of whaling in the 1970s it is recovering, but the timing and level of recovery is uncertain. We implemented a Bayesian population dynamics model describing the population's trajectory from 1901 and projecting it to 2040 to revise a previous population status assessment that used Sampling-Importance-Resampling in a Bayesian framework. Using our alternative method for model fitting (Markov chain Monte Carlo), which is more widely accessible to ecologists, we replicate a "base case scenario" to verify the effect on model results, and introduce additional data to update the status assessment. Our approach allowed us to widen the previous informative prior on carrying capacity to better reflect scientific uncertainty around historical population levels. The updated model provided more precise estimates for population sizes over the period considered (1901-2040) and suggests that carrying capacity (K: median 22,882, mean 22,948, 95% credible interval [CI] 22,711-23,545) and minimum population size (N1958: median 305, mean 319, 95% CI 271-444) might be lower than previously estimated (K: median 24,558, mean 25,110, 95% CI 22,791-31,118; N1958: median 503, mean 850, 95% CI 159-3,943). However, posterior 95% credible intervals of parameters in the updated model overlap those of the previous study. Our approach provides an accessible framework for investigating the status of depleted animal populations for which information is available on historical mortality (e.g., catches) and intermittent estimates of population size and/or trend.

Journal Article||Research Support, Non-U.S. Gov't

https://pubmed.ncbi.nlm.nih.gov/34788309/

Modelo de dinámica poblacional Bayesiano

Modelo de Dinámica Poblacional Bayesiano

(Tamaño inicial ed la población, Tasa de Natalidad, Tasa de Mortalidad, Tasa de inmigración, Tasa de emigración, Captura anual, Esfuerzo de Caza)

The population of humpback whales (Megaptera novaeangliae) wintering off the eastern coast of South America is referred to by the International Whaling Commission as 'Breeding Stock A' (BSA). This population was heavily exploited in 20 th century modern commercial whaling operations. After more than 30 years of protection, its present status remains unknown. A deterministic sex and age-aggregated population dynamics model was used to estimate the pre-exploitation population size (K), the maximum net recruitment rate (r max, the maximum depletion level (NJK), and other quantities of interest of BSA. Input data included modem whaling catch series, absolute estimates of abundance, observed growth rates and indices of relative abundance. A Bayesian statistical method was used to calculate probability distributions for the model parameters. Prior distributions were set on r - an uninformative (Uniform [0, 0.106]) and an informative (Normal [0.067,0.04 2]) - and on the population size in 2005 - N 2005 (Uniform [500,22,000]). A total of 10,000 samples were used to compute the joint posterior distribution of the model parameters using the Sampling-Importance-Resampling algorithm. Sensitivity of model outputs to the priors on r max, a genetic constraint, data inclusion and catch allocation scenarios was investigated. Medians of the posterior probability distributions of quantities of interest for the base case scenario were: r max = 0069 ( 95% probability intervals [PI] = 0.013-0.104), K = 24,558 (95% PI = 22,791-31,118), NJK = 2% (PI = 0.31%-12.5%), N 200d K = 27.4% (PI = 18.3%-39.5%), N 2020ZK = 61.8% (PI = 23.8%-88.6%), and N 204JK= 97.3% (PI = 31.6%-99.9%). Despite apparent recovery in the past three decades, the western South Atlantic humpback whale population is still low relative to its pre-exploitation size and requires continued conservation efforts.

Journal of Cetacean Research and Management

https://www.scopus.com/inward/record.uri?eid=2-s2.0-84865327390&partnerID=40&md5=b01f28e0e9de9f2f68bb45fa4571524c

Modelo Bayesiano de dinámica de poblaciones de dos sexos y edades agregadas

Modelo de Dinámica Poblacional Bayesiano de dos sexos y edades agregados

Tamaño de la población pre-explotación, Tasa máxima de crecimiento, Tasa de recuperación, Capácidad de carga, Desviación estandar del proceso de crecimiento, Curva de captura, Sensibilidad a la captura

Historical harvesting pushed many whale species to the brink of extinction. Although most Southern Hemisphere populations are slowly recovering, the influence of future climate change on their recovery remains unknown. We investigate the impacts of two anthropogenic pressures-historical commercial whaling and future climate change-on populations of baleen whales (blue, fin, humpback, Antarctic minke, southern right) and their prey (krill and copepods) in the Southern Ocean. We use a climate-biological coupled "Model of Intermediate Complexity for Ecosystem Assessments" (MICE) that links krill and whale population dynamics with climate change drivers, including changes in ocean temperature, primary productivity and sea ice. Models predict negative future impacts of climate change on krill and all whale species, although the magnitude of impacts on whales differs among populations. Despite initial recovery from historical whaling, models predict concerning declines under climate change, even local extinctions by 2100, for Pacific populations of blue, fin and southern right whales, and Atlantic/Indian fin and humpback whales. Predicted declines were a consequence of reduced prey (copepods/krill) from warming and increasing interspecific competition between whale species. We model whale population recovery under an alternative scenario whereby whales adapt their migratory patterns to accommodate changing sea ice in the Antarctic and a shifting prey base. Plasticity in range size and migration was predicted to improve recovery for ice-associated blue and minke whales. Our study highlights the need for ongoing protection to help depleted whale populations recover, as well as local management to ensure the krill prey base remains viable, but this may have limited success without immediate action to reduce emissions.

Global change biology

Journal Article

https://pubmed.ncbi.nlm.nih.gov/30807685/

Modelo de ecosistema dinámico (MICE)

Modelo de Ecosistema Dinámico

Tasa de crecimiento del Krill, Capacidad de carga del krill, Tasa de depredación del krill por ballenas, Tasa de depredación de krill por otros predadores, Tasa de crecimiento intrínseco de las ballenas, Capacidad de carga de ballenas, Párametros de eficiencia de forrajeo de ballenas, Tasa de captura de krill

Humpback whale song is an extraordinary example of vocal cultural behaviour. In northern populations, the complex songs show long-lasting traditions that slowly evolve, while in the South Pacific, periodic revolutions occur when songs are adopted from neighbouring populations and rapidly spread. In this species, vocal learning cannot be studied in the laboratory, learning is instead inferred from the songs' complexity and patterns of transmission. Here, we used individual-based cultural evolutionary simulations of the entire Southern and Northern Hemisphere humpback whale populations to formalize this process of inference. We modelled processes of song mutation and patterns of contact among populations and compared our model with patterns of song theme sharing measured in South Pacific populations. Low levels of mutation in combination with rare population interactions were sufficient to closely fit the pattern of diversity in the South Pacific, including the distinctive pattern of west-to-east revolutions. Interestingly, the same learning parameters that gave rise to revolutions in the Southern Hemisphere simulations gave rise to evolutionary patterns of cultural evolution in the Northern Hemisphere populations. Our study demonstrates how cultural evolutionary approaches can be used to make inferences about the learning processes underlying cultural transmission and how they might generate emergent population-level processes. This article is part of the theme issue 'Vocal learning in animals and humans'.

Philosophical transactions of the Royal Society of London. Series B, Biological sciences

Journal Article||Research Support, Non-U.S. Gov't

https://pubmed.ncbi.nlm.nih.gov/34482732/

(Tasa de aprendizaje, Precisión del aprendizaje, Edad de aprendizaje, Tasa de transmisión, Rango de transmisión, Fuerza de selección, Rasgos seleccionados, Tasa de mutación, Tipo de mutación, Tamaño poblaciona, Tasa de natalidad, Tasa de mortalidad, Calidad de hábitat, Disponibilidad de recursos).

The contribution of prey species to the diet and their variation over time are poorly understood processes in the trophic ecology of Southeast Pacific humpback whales (Megaptera novaeangliae). The purpose of this study was to use carbon and nitrogen stable isotopes to provide insights into the trophic ecology and to determine the inter-annual variation of the diet of the humpback whales in the Magellan Strait. During 2011 and 2012, an analysis was carried out to determine the isotopic composition of humpback whale skin. We used a Bayesian isotope mixing model to determine the relative contribution of prey species to the isotopic value of the consumer. The humpback whale had mean values of -16.3 ± 0.6‰ in δ13C and 14.7 ± 1.0‰ in δ15N (n = 33). The δ13CC and δ15N in both the whales and the Fuegian sprat (Sprattus fueguensis) were significantly higher in 2011 compared to 2012. Additionally, females had significantly higher δ15N values in 2012; however, mean δ13CC and δ15N values of whales within each season and between age classes did not differ statistically. A variation was observed in the contribution of different prey to the whale diet between the study years, with Fuegian sprat as the predominant prey during 2011 (mean 55 ± 12%), and crustaceans dominating the diet in 2012 (mean 82 ± 9%). This study confirms the diet of the humpback whale within the Magellan Strait. Furthermore, isotopic analyses suggest important inter-annual changes due to (1) changes in the proportion of the species being consumed, probably due to variations in availability (e.g., abundance) of prey; and/or (2) annual isotopic changes at the base of the food web. Further studies are required on the population dynamics of prey in order to monitor annual changes in abundance and food supply.

Aquatic Mammals

https://www.scopus.com/inward/record.uri?eid=2-s2.0-84978878012&doi=10.1578%2fAM.42.2.2016.233&partnerID=40&md5=d232801591511efaeb7b754884de597e

Razones de isótopos estables de (δ13C) y nitrógeno (δ15N), Razones de isótopos estables de carbono y nitrogeno en las posibles fuentes de alimentos, Proporción de cada fuente de alimento en la mezcla

BACKGROUND: Detailed information about animal location and movement is often crucial in studies of natural behaviour and how animals respond to anthropogenic activities. Dead-reckoning can be used to infer such detailed information, but without additional positional data this method results in uncertainty that grows with time. Combining dead-reckoning with new Fastloc-GPS technology should provide good opportunities for reconstructing georeferenced fine-scale tracks, and should be particularly useful for marine animals that spend most of their time under water. We developed a computationally efficient, Bayesian state-space modelling technique to estimate humpback whale locations through time, integrating dead-reckoning using on-animal sensors with measurements of whale locations using on-animal Fastloc-GPS and visual observations. Positional observation models were based upon error measurements made during calibrations. RESULTS: High-resolution 3-dimensional movement tracks were produced for 13 whales using a simple process model in which errors caused by water current movements, non-location sensor errors, and other dead-reckoning errors were accumulated into a combined error term. Positional uncertainty quantified by the track reconstruction model was much greater for tracks with visual positions and few or no GPS positions, indicating a strong benefit to using Fastloc-GPS for track reconstruction. Compared to tracks derived only from position fixes, the inclusion of dead-reckoning data greatly improved the level of detail in the reconstructed tracks of humpback whales. Using cross-validation, a clear improvement in the predictability of out-of-set Fastloc-GPS data was observed compared to more conventional track reconstruction methods. Fastloc-GPS observation errors during calibrations were found to vary by number of GPS satellites received and by orthogonal dimension analysed; visual observation errors varied most by distance to the whale. CONCLUSIONS: By systematically accounting for the observation errors in the position fixes, our model provides a quantitative estimate of location uncertainty that can be appropriately incorporated into analyses of animal movement. This generic method has potential application for a wide range of marine animal species and data recording systems.

Movement ecology

Journal Article

https://pubmed.ncbi.nlm.nih.gov/26392865/

Modelo de movimiento de estado lineal

Modelo de Movimiento de Estado Lineal

Posición de la ballena, Posición del barco, Velocidad del barco, Rumbo del barco, Tiempo

(0° - 2° S, 80° - 82° W),(4° N - 4° S, 77° - 79° W.)

The western South Atlantic humpback whale Megaptera novaeangliae population was severely depleted by commercial whaling in the late 19th and 20th centuries, and today inhabits a human-impacted environment in its wintering grounds off the Brazilian coast. We identified distribution patterns related to environmental features and provide new estimates of population size, which can inform future management actions. We fitted spatial models to line transect data from 2 research cruises conducted in 2008 and 2012 to investigate (1) habitat use and (2) abundance of humpback whales wintering on the Brazilian continental shelf. Potential explanatory variables were year, depth, seabed slope, sea-surface temperature (SST), northing and easting, current speed, wind speed, distance to the coastline and to the continental shelf break, and shelter (a combination of wind speed and SST categories). Whale density was higher in slower currents, at shorter distances to both the coastline and shelf break, and at SSTs between 24 and 25°C. The distribution of whales was also strongly related to shelter. For abundance estimation, easting and northing were included in the model instead of SST; estimates were 14 264 whales (CV = 0.084) for 2008 and 20 389 (CV = 0.071) for 2012. Environmental variables explained well the variation in whale density; higher density was found to the south of the Abrolhos Archipelago, and shelter seems to be important for these animals in their breeding area. Estimated distribution patterns presented here can be used to mitigate potential human-related impacts, such as supporting protection in the population’s core habitat near the Abrolhos Archipelago. © Inter-Research 2017

Marine Ecology Progress Series

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85039936650&doi=10.3354%2fmeps12393&partnerID=40&md5=aaded5c29fb49b6bd6ebe294bfd3d2ac

Modelo de regresión espacial binomial

Modelo de Regresión Espacial Binomial

Profundidad, Distancia a la costa, Termperatura supercial del mar, Corrientes, Velocidad del viento, Dirección del viento

Brasil(Banco de Abrolhos, Vitória-Trinidade)

This study encompasses a series of interrelated experiments regarding the appropriate handling of samples and the interpretation of measurements of estradiol (described here for the first time in cetacean blubber), progesterone, and testosterone from both live and dead humpback whales. The experiments determined the effects on hormone levels of the following parameters: the state of decomposition of the blubber, the location on the body, the depth of the blubber layer, and the mass of the analyzed sample. The decomposition of carcasses for up to six days (144 h) after death of the animal under natural conditions increased the levels of all three hormones. The dorsal fin presented higher levels of testosterone than other locations. The outer layer of blubber in decomposing samples exhibited higher values of progesterone and estradiol than the middle and inner layers and also exhibited a greater amount of extracted lipids. A lack of adjustment for relative volumes of extract and solvent led to an inverse relationship between hormone level and sample mass; smaller samples (25–50 mg) exhibited higher levels of hormones than did larger ones (50–300 mg). Certain data adjustments are proposed to minimize the effect of sample mass on hormone measurement, including the use of an alternative mass unit (amount of extracted lipid). The methodological approaches presented here contribute to the better standardization of this emerging technique and thereby facilitate the comparison of hormone levels among different cetacean populations and species. © 2016 Elsevier B.V.

Journal of Experimental Marine Biology and Ecology

https://www.scopus.com/inward/record.uri?eid=2-s2.0-84988985336&doi=10.1016%2fj.jembe.2016.09.010&partnerID=40&md5=daa9b603c96d2cc0e59004419e15c9f8

Estado de descomposición, Zona corporal, Profundidad de la capa de grasa, Tamaño de la muestra, Tipo de hormona sexual)

Humpback whales perform long migrations from their breeding and nursing areas at low latitudes to feeding grounds at high latitudes. Nonetheless, this strictly dichotomous paradigm of migration is challenged by accumulating examples of occasional or regular feeding at low latitudes for several stocks worldwide. Here, we report multiple evidences of “Stock G” humpback whales feeding in coastal waters, at low latitudes of the Southeast Pacific Ocean. Lunge feeding behavior and defecation were observed in Ecuador, while both lunge- and trap feeding in pursuit of Peruvian anchovy was documented in northern Chile. A photographically re-sighted individual feeding at different latitudes of Chile suggested potential site fidelity to two foraging areas. Whether these feeding behaviours are novel due to changes in prey distribution, intensifying competition from a growing humpback whale population, or simply reflect vastly increased research effort remains unknown. Further research into the feeding ecology of Stock G should help reveal historic and potentially new feeding grounds, prey composition and precise migration paths. Competition from anchovy fisheries, vessel collision and net entanglement are suspected threats. © 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.

Neotropical Biodiversity

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85116808633&doi=10.1080%2f23766808.2021.1971041&partnerID=40&md5=002a74651ea1328e3acad1b51926ecad

Presencia de BJ, Temperatura del agua, Profundidad, Productividad

Chile(Bahía de Mejillones y Península de Mejillones),Ecuador(Parque nacional Machalilla y Isla de la Plata)

One of the humpback whales' stocks uses the Brazilian Coast as breeding and calving ground during the austral winter. The species is recovering from commercial hunting and re-occupying previous breeding areas. Aerial surveys conducted to estimate the species density and abundance along the continental shelf of the Eastern Brazilian Coast revealed important core areas at the southern portion of the Abrolhos Bank. The rapid growth of human activities in these coastal areas motivated the use of Geographic Information Systems as a tool to guide the identification of priority areas for the species conservation. The species distribution was modelled using a kernel density estimator. The corresponding layer was used to identify areas of overlay with components of maritime traffic and with hydrocarbon exploitation areas. The resulting risk map was overlaid with existent Marine Protected Areas, allowing the cartography of areas where management measures still need to be undertaken to ensure habitat protection. These areas were identified as priorities for the species conservation as they encompass important breeding concentrations that were completely overlain by areas used to hydrocarbon exploitation and/or as navigation corridors. The present work gives support to an ecosystem-based management and ocean zoning of this portion of the Brazilian coast. © 2013 Elsevier Ltd.

Ocean and Coastal Management

https://www.scopus.com/inward/record.uri?eid=2-s2.0-84874772667&doi=10.1016%2fj.ocecoaman.2013.02.006&partnerID=40&md5=da2c792d477a42bd2eb54ef85bd58cdb

Densidad de BJ hembras con crías, Temperatura superficial del mar, Profundidad del agua, Distancia a la costa

Brasil (Rio Grande del Norte: Bahía)

Humpback whale Megaptera novaeangliae (Cetartiodactyla: Balaenopteridae) group sizes in line transect ship surveys: An evaluation of observer errors

Accurate estimates of group sizes through line transect sampling methods are important to correctly ascertain the abundance of animals that occur in groups. Since the average observed group size is a component of the distance sampling formula, bias in these data leads to biased abundance estimates. This study aimed to evaluate the potential errors in group size estimation during line transect ship surveys to estimate abundances of the humpback whale, Megaptera novaeangliae (Borowski 1781). In a research cruise along the Brazilian coast, an experiment to collect group size information was conducted from two different sighting platforms on the same vessel. Group sizes were recorded by primary observers at first sighting (PO1) and, in some cases, after some time (PO2). A tracker (T) was located on a higher platform to estimate the sizes of groups detected by the primary observers, but tracked one group at a time until it passed abeam. Thus, the dedicated effort to obtain multiple group counts (i.e. higher platform, more time and no responsibility for detecting new groups) was expected to provide more accurate numbers. PO2 estimates were compared with PO1 estimates, and T estimates were compared with both PO1 and PO2. Additionally, ratios between T and both PO2 (R1) and PO1 (R2), and between PO2 and PO1 (R3) were calculated. To investigate a possible improvement in abundance estimates, a correction factor (CF) was computed from the ratio of T and PO2 means. Primary observer self-correction (= 1.60, CV% = 70.3) was statistically similar to the correction for the tracker (= 1.62, CV% = 84.1). CF resulted in 1 and would not improve abundance estimates. This study supports that observers conducting line transect surveys on large whales have the potential to provide group size information that is as adequate as the correction procedure adopted. © 2016, Sociedade Brasileira de Zoologia. All rights reserved.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-84966335526&doi=10.1590%2fS1984-4689zool-20150133&partnerID=40&md5=c6ef7633f571426f547809933c03c654

Modelo de Regresión Lineal Generalizado

Tamaño del grupo estimado por PO1/PO2, Tamaño del grupo estimado por T, Condiciones climaticas, Distancia a la ballena, Comportamiento

Brasil(Salvador (Bahía), Cabo Frío, Rio de Janerio, Banco de Abrolhos)

The Magellan Strait is a narrow passage connecting the Pacific and Atlantic oceans in South America. An average of 2023 ships per year transit this corridor with 80% representing the international fleet. The southwestern part of the Strait in Chile is an important summer feeding area for humpback whales. Considering the risk to whales of feeding among dense ship traffic, the movements of 25 satellite-tagged whales relative to vessel density were analyzed, to provide policy recommendations for protecting the species from vessel collisions. A total of 3694 filtered whale positions from 21 individuals were obtained along the southwest passage. The daily range covered by individual whales was 8.8 km, and <25 km on 90% of all days. Ship density in the same square kilometers where whales were encountered was 0.27 per week, slightly more often than once per month, however this encounter rate varied by 100-fold between individuals, depending on how often animals were in the central shipping lane. One of the tagged whales stopped transmitting and washed up dead suggesting a ship strike. In the last decade, four other humpback whales and three sei whales were killed by probable ship strikes, all near Isla Carlos III, the core of the humpback feeding area. A 10-knot speed restriction and onboard observers are recommended during the five months of maximum whale abundance, applying to all merchant vessels traveling through the Strait, between Cabo Holland and Isla Bonete north of Carlos III Island, for a distance of 28 nautical miles (52 km). © 2020

Marine Policy

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85083768736&doi=10.1016%2fj.marpol.2020.103990&partnerID=40&md5=e50813305a8210ce5101a0fcf8ac1dbd

Modelo de regresión lineal generalizada, Modelo de análisis de nichos espaciales

Modelo de Regresión Lineal Generalizado

Clase de ballenas, Presencia de buques, Temperatura del mar, Profundidad del agua, Distancia a la costa, Distancia recorrida por la ballenas en 2 horas

During the austral winter, G-stock humpback whales, Megaptera novaeangliae, migrate to the Tropical Eastern Pacific to breed. To analyse if the whale migration times have changed over time, we analysed 31 years (1988-2018) of arrival and departure times to Gorgona National Park, Colombia, an important breeding site. During this period, whales have significantly changed their arrival time, coming now earlier, but their departure time has not changed significantly. Hence, humpback whales now stay 1 month longer than 31 years ago. Humpbacks arrived in Gorgona at the earliest during the beginning of May and stayed at the most until late December. The change observed in the arrival time to breeding grounds could be related to ice sheet mass changes in autumn in Antarctica and increase in population size over the past decades but we were unable to determine which factor is more important in explaining the observed trend. Management decisions in Colombia need to account for a longer stay, specifically restricting anthropogenic activities from 1May to 31December. We urge other researchers to review their data, in case this shift is evident in other regions and management plans need to be updated. © 2019 International Council for the Exploration of the Sea 2019. All rights reserved. For permissions, please email: journals.permissions@oup.com.

ICES Journal of Marine Science

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85082076003&doi=10.1093%2ficesjms%2ffsz251&partnerID=40&md5=9fc0b936f5068a8fbdde9b3717821adb

Modelo de Regresión Lineal Generalizado

Año, Fecha de llegada de las ballenas

Colombia(Paque natural Gorgonas)

The coast of Brazil is an important low latitude nursery ground for humpback whales (Megaptera novaeangliae). The number of humpback whales in this region has increased and its population is reoccupying areas where it has been depleted during the whaling period. The goal of this study was to conduct land-based observations during 2014 and 2015 to characterize patterns of habitat use and relative abundance of humpback whales that migrate to one of these reoccupation areas: Serra Grande, Bahia state. The observed mean group size was 2.12 ± 0.96 individuals and did not vary through the reproductive season nor between years. Dyads (32.9%) and singletons (26.7%) were more frequently observed, and groups with calves represented 21.2% of the sightings. The mean number of whales counted per hour increased from 2014 (3.44 ± 3.35) to 2015 (5.12 ± 4.18). Habitat use varied during the season; whales used shallower waters closer to shore as the season progressed. The spatial distribution of groups with calves was dependent on the presence and number of escorts. Spatial segregation of groups with calves closer to shore is a key factor in understanding the overall distribution of whales in the area, suggesting that social strategies are affected by environmental factors, as seen in other wintering grounds. Small-scale studies from land-based stations, in areas such as this where there is no previous knowledge about the species, are cost effective. They provide information about the overall behavioural and spatial patterns while anthropogenic activity is still low, allowing habitat protection and management decisions before implementation and increase of human activities. Copyright © Marine Biological Association of the United Kingdom 2018.

Gonçalves M.I.C.; De Sousa-Lima R.S.; Teixeira N.N.; Morete M.E.; De Carvalho G.H.; Ferreira H.M.; Baumgarten J.E.

Journal of the Marine Biological Association of the United Kingdom

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85045315312&doi=10.1017%2fS0025315418000255&partnerID=40&md5=2b4a811537a45224e3f6ab54ba2f2298

Modelo de Regresión Lineal Generalizado

Distancia a la costa, Año, Mes, Hora del día, Composición del grupo, Comportamiento

Satellite tracking and sighting data analyses of Southeast Pacific humpback whales (Megaptera novaeangliae): Is the migratory route coastal or oceanic?

This paper presents an analysis of the migra-tion movements of Southeast Pacific humpback whales (Megaptera novaeangliae) based on satellite and sighting data. We used informa-tion obtained from six humpback whales tagged off the coast of Ecuador between August and September 2013, and sighting information from oceanographic cruises and seismic prospection studies. Tagged humpback whales were followed along the west coast of South America, and in one case off the Antarctic Peninsula, for between 11 and 72 d. Distance covered by tracked whales was between 920 and 8,670 km. While available sight-ing data indicated that humpback whales follow a coastal route, satellite tracking data show that single adults use a more direct offshore route and mother/calf pairs tend to follow the longer coastal route. A 4-d period of irregular movements by a mother with a calf off central Peru suggested foraging behavior in this area characterized by intense upwelling processes. On the other hand, the humpback whale that reached Antarctic waters by mid-October quickly moved 200 km off the Antarctic Peninsula, probably because the zone was still covered by ice. We also found differ-ences in travel speed between age/sex classes of humpback whales with mother/calf pairs traveling about 30% slower than single adults. The aver-age humpback whale swim speed ranged between 65.5 and 169 km.d-1. Our information provides a first examination of potential routes used by this whale population and highlights the need for a regional approach in appropriately addressing the migratory behavior and threats to the species during its annual migration.

Aquatic Mammals

https://www.scopus.com/inward/record.uri?eid=2-s2.0-84986208859&doi=10.1578%2fAM.40.4.2014.329&partnerID=40&md5=7655b45113111c05429a7c5d4476d989

Modelo de regresiíon lineal generalizada

Modelo de Regresión Lineal Generalizado

Probabilidad de avistamiento de BJ, Distancia a la acosta, Temporada, Año, Temperatura del mar, Productividad del óceano

Humpback whales have a cosmopolitan distribution and undertake annual migrations between low and high latitudes where breeding and feeding takes place, respectively. In Brazil, the main breeding area encompasses the Abrolhos Bank at the Eastern Brazilian Coast and the feeding area of this population is located in South Georgia and South Sandwich Islands. Here, two recent records of humpback whales are reported for Maranhão State, Amazonian Equatorial Coast (AEC), one of which involves a newborn calf with remains of the umbilical cord. Additionally, an in-depth review of the stranding and observation records for this area is presented. Phylogenetic analysis placed the stranded animals within the two most common haplogroups reported for the Southern Hemisphere breeding grounds (CD and IJ). A possible extension of the species range or the recolonization of a historical breeding area along the Brazilian coast is discussed. Presented results provide evidence of distribution overlap between the humpback whale populations of the northern and southern Atlantic Ocean which will require the development of conservation strategies among neighboring countries and underline the need to develop management strategies that will allow sustainable management of the Amazonian Equatorial Coast. © 2019 The Authors

Ristau N.G.; Martins C.C.A.; Luvizotto-Santos R.; Balensiefer D.; Sousa G.; Marmontel M.; Farias I.P.

Global Ecology and Conservation

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85078400353&doi=10.1016%2fj.gecco.2019.e00854&partnerID=40&md5=26b1c761d699b76f90614477426521d8

Modelo de regresión lineal generalizada

Modelo de Regresión Lineal Generalizado

Presencia/ausencia de BJ, Temperatura del agua, Profundidad, Distancia a la costa, Mes, Año, Área de estudio

Compared with other Chilean coastal areas, little is known about the diversity and distribution of cetaceans in northern Patagonian fjords. Between December 2000 and November 2001, surveys on platforms of opportunity were undertaken in southern Chile to evaluate species richness and the spatial and seasonal distribution of cetaceans. Nine species were recorded, blue, humpback, and minke whales, Peale's dolphin, Chilean dolphin, killer whale, false killer whale, bottlenose dolphin, and Cuvier's beaked whale. The pattern of cetacean distribution displayed significant seasonal differences, with most baleen whales (mysticetes) observed during late summer and autumn, and toothed cetaceans (odontocetes) mostly during spring. Generalized additive models, used to assess the spatial distribution of cetaceans, showed that mysticetes were distributed disproportionately along a north-south gradient, in open gulfs with oceanic influence, and close to shore. In contrast, odontocetes were observed mainly within narrow channels, areas with complex coastal morphology, peaking at different water depths. These findings, although from a single year of data, increase our understanding of habitat determinants of cetacean distribution in southern Chile. The results have the potential to be applied to coastal conservation and management in the region. © 2009 International Council for the Exploration of the Sea. Published by Oxford Journals. All rights reserved.

ICES Journal of Marine Science

https://www.scopus.com/inward/record.uri?eid=2-s2.0-77953642055&doi=10.1093%2ficesjms%2ffsp288&partnerID=40&md5=1c1c9eedd2df9a1cb4caaa9977906422

Modelo de Regresión Lineal Generalizado

Latitud, Longitud, Profundidad del agua, Temperatura del agua, Salinidad, Claridad del agua, Presencia/Ausencia de cetáceos

Is it possible to go whale watching off the coast of peru? A case study of humpback whales; [¿es posible hacer turismo de observación de ballenas en la costa de Perú? Un caso de estudio con ballenas jorobadas]

Whale watching is the human activity of encountering cetaceans in their natural habitat for recreational and scientific purposes. Despite the high diversity of cetaceans in Peruvian waters, this activity has yet to be developed. Herein we present data regarding the distribution of humpback whales (Megaptera novaeangliae) off northern Peru, evaluating the possibility of extending whale watching activities in this area. Data were obtained from surveys conducted from an ecotourism boat. Humpbacks were distributed in shallow waters, usually in pairs or trios throughout the study period between late July and late September. The presence of whales off northern Peru is due to winter migration for breeding and calving purposes. A high probability of encountering humpbacks within the study area could encourage the development of a whale watching industry. As this stage in the life cycle of this species is very delicate, we suggest the adoption of the precautionary principle in the management of the activity in order to minimize the risk of negative impacts on humpback populations. Whale watching in northern Peru is feasible and could be considered an alternative to fishing.

Latin American Journal of Aquatic Research

https://www.scopus.com/inward/record.uri?eid=2-s2.0-79955919162&doi=10.3856%2fvol39-issue1-fulltext-20&partnerID=40&md5=f75faf0a96ec8dcf07259b6ea24e5c47

Modelo de Regresión Logistica

Intercepto, Coeficiente de regresión para la altura de las olas, coeficiente de regresión para la cobertura de las nubes

We report the first documented movement of an individual humpback whale between the eastern South Pacific stock off Ecuador and the western South Atlantic stock off Brazil. This constitutes the first record of a humpback whale in both the Atlantic and Pacific breeding grounds off South America, and one of a small number of inter-oceanic movements documented to date. It is possible that, even at quite low levels, this movement of individuals between breeding grounds contributes to the current high level of mtDNA diversity in these once-dcplcted Southern Hemisphere populations. When first sighted, the whale was accompanied by a young calf, and is therefore identified as an adult female. This movement to a different and distant breeding ground is the first reported by a reproductivcly mature female, and shows that extreme long-distance travellers among humpback whales arc not restricted to young males.

Journal of Cetacean Research and Management

https://www.scopus.com/inward/record.uri?eid=2-s2.0-84910632482&partnerID=40&md5=50d98d0376e31791c5d0067c4861480b

Modelo de simulación individual basado en agentes

Modelo de Simulación Individual Basado en Agentes

Velocidad de natación, Dirección de natación, Tasa de mortalidad, Disponibilidad de alimento

Baleen whales are vulnerable to environmental impacts due to low fecundity, capital breeding strategies, and their reliance on a large amount of prey resources over large spatial scales. There has been growing interest in monitoring health and physiological stress in these species but, to date, few measures have been validated. The purpose of this study was to examine whether blubber cortisol could be used as a measure of physiological stress in humpback whales. Cortisol concentrations were initially compared between live, presumably 'healthy' whales (n = 187) and deceased whales (n = 35), which had died after stranding or entanglement, or washed ashore as a carcass. Deceased whales were found to have significantly higher cortisol levels (mean +/- SD; 5.47 +/- 4.52 ng/g) than live whales (0.51 +/- 0.14 ng/g; p < 0.001), particularly for those animals that had experienced prolonged trauma (e.g. stranding) prior to death. Blubber cortisol levels in live whales were then examined for evidence of life history-related, seasonal, or sampling-related effects. Life history group and sampling-related factors, such as encounter time and the number of biopsy sampling attempts per animal, were found to be poor predictors of blubber cortisol levels in live whales. In contrast, blubber cortisol levels varied seasonally, with whales migrating north towards the breeding grounds in winter having significantly higher levels (0.54 +/- 0.21 ng/g, p = 0.016) than those migrating south towards the feeding grounds in spring (0.48 +/- 1.23 ng/g). These differences could be due to additional socio-physiological stress experienced by whales during peaks in breeding activity. Overall, blubber cortisol appears to be a suitable measure of chronic physiological stress in humpback whales.

General and comparative endocrinology

2020 May 15

Journal Article||Research Support, Non-U.S. Gov't

https://pubmed.ncbi.nlm.nih.gov/32057910/

Intercepto, Coeficiente de regresión para la temperatura del agua, Coeficiente de regresión para la profundidad, Efecto aleatorio de la ballena, Error aleatorio

Empirical evaluation of humpback whale telomere length estimates; quality control and factors causing variability in the singleplex and multiplex qPCR methods.

BACKGROUND: Telomeres, the protective cap of chromosomes, have emerged as powerful markers of biological age and life history in model and non-model species. The qPCR method for telomere length estimation is one of the most common methods for telomere length estimation, but has received recent critique for being too error-prone and yielding unreliable results. This critique coincides with an increasing awareness of the potentials and limitations of the qPCR technique in general and the proposal of a general set of guidelines (MIQE) for standardization of experimental, analytical, and reporting steps of qPCR. In order to evaluate the utility of the qPCR method for telomere length estimation in non-model species, we carried out four different qPCR assays directed at humpback whale telomeres, and subsequently performed a rigorous quality control to evaluate the performance of each assay. RESULTS: Performance differed substantially among assays and only one assay was found useful for telomere length estimation in humpback whales. The most notable factors causing these inter-assay differences were primer design and choice of using singleplex or multiplex assays. Inferred amplification efficiencies differed by up to 40% depending on assay and quantification method, however this variation only affected telomere length estimates in the worst performing assays. CONCLUSION: Our results suggest that seemingly well performing qPCR assays may contain biases that will only be detected by extensive quality control. Moreover, we show that the qPCR method for telomere length estimation can be highly precise and accurate, and thus suitable for telomere measurement in non-model species, if effort is devoted to optimization at all experimental and analytical steps. We conclude by highlighting a set of quality controls which may serve for further standardization of the qPCR method for telomere length estimation, and discuss some of the factors that may cause variation in qPCR experiments.

BMC genetics

Journal Article||Research Support, Non-U.S. Gov't

https://pubmed.ncbi.nlm.nih.gov/22954451/

Longitud telomérica, Método de qPCR, Calidad de ADN, Edad de la ballena, Sexo de la ballena, Estado reproductivo de la ballena, Método de extracción de ADN, Localidad del estudio

Movement patterns of humpback whales (Megaptera novaeangliae) reoccupying a Brazilian breeding ground; [Padrões de movimento das baleias-jubarte (Megaptera novaeangliae) reocupando uma área reprodutiva Brasileira]

The population of humpback whales from breeding stock A is increasing, and little is known about the routes used by humpbacks that move north of the main calving area of Brazil, the Abrolhos Bank. The aim of this study was to describe the movements of humpback whales in a reoccupation wintering area (Serra Grande, Bahia state, Brazil) based on land-based surveys to test if movement patterns change during the season and between years, due to group composition, behavioral state, and distance to the coast. The mean leg speed of the groups sighted was 6.88 (±2.92) km/h, and leg speed was positively correlated with distance to the coast. There was an increase in leg speed and distance to the coast with increasing number of escorts in the groups with calves. The mean linearity value for group trajectory was 0.81 (±0.19) and the mean reorientation rate was 25.72 (±19.09) º/min. We observed a predominance of trajectories heading south throughout the study. Groups exhibiting more erratic movements early in the season, and groups moving south showed more linear trajectories than groups moving north, indicating the beginning of their migration back to the feeding grounds. Energy conserving strategies and social context affect the movements of humpback whales in Serra Grande, resulting in the observed patterns of the reoccupation of available and suitable habitat north of Abrolhos. Thereby, special attention should be given managing activities with the potential to disturb or displace whales using the region to calve and breed. © 2018, Universidade Estadual de Campinas UNICAMP. All rights reserved.

Gonçalves M.I.C.; de Sousa-Lima R.S.; Teixeira N.N.; Carvalho G.H.; Danilewicz D.; Baumgarten J.E.

Biota Neotropica

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85056417796&doi=10.1590%2f1676-0611-bn-2018-0567&partnerID=40&md5=13baa29f51d8285dbe8b57c1ccb4068e

Velocidad de las ballenas, Distancia a la costa, Tamañao del grupo, Precencia de crías, Época del año, Condiciones ambientales

Brasil(Praia do Forte, Ponta do Corumbau)

Glucocorticoids are regularly used as biomarkers of relative health for individuals and populations. Around the Western Antarctic Peninsula (WAP), baleen whales have and continue to experience threats, including commercial harvest, prey limitations and habitat change driven by rapid warming, and increased human presence via ecotourism. Here, we measured demographic variation and differences across the foraging season in blubber cortisol levels of humpback whales (Megaptera novaeangliae) over two years around the WAP. Cortisol concentrations were determined from 305 biopsy samples of unique individuals. We found no significant difference in the cortisol concentration between male and female whales. However, we observed significant differences across demographic groups of females and a significant decrease in the population across the feeding season. We also assessed whether COVID-19-related reductions in tourism in 2021 along the WAP correlated with lower cortisol levels across the population. The decline in vessel presence in 2021 was associated with a significant decrease in humpback whale blubber cortisol concentrations at the population level. Our findings provide critical contextual data on how these hormones vary naturally in a population over time, show direct associations between cortisol levels and human presence, and will enable comparisons among species experiencing different levels of human disturbance.

Pallin LJ||Botero-Acosta N||Steel D||Baker CS||Casey C||Costa DP||Goldbogen JA||Johnston DW||Kellar NM||Modest M||Nichols R||Roberts D||Roberts M||Savenko O||Friedlaender AS

Scientific reports

2022 Nov 24

Journal Article||Research Support, Non-U.S. Gov't||Research Support, U.S. Gov't, Non-P.H.S.

https://pubmed.ncbi.nlm.nih.gov/36424421/

Niveles de cortisol en la grasa, Sexo, Étapa reproductiva de la hembra, Época del año, Presencia de Turismo,

Oceáno Austral(Península Antártica Occidental, Islas Shetland, Isla Decepción)

The recovery of whale populations from centuries of exploitation will have important management and ecological implications due to greater exposure to anthropogenic activities and increasing prey consumption. Here, a Bayesian population model integrates catch data, estimates of abundance, and information on genetics and biology to assess the recovery of western South Atlantic (WSA) humpback whales (Megaptera novaeangliae). Modelling scenarios evaluated the sensitivity of model outputs resulting from the use of different data, different model assumptions and uncertainty in catch allocation and in accounting for whales killed but not landed. A long period of exploitation drove WSA humpback whales to the brink of extinction. They declined from nearly 27 000 (95% PI = 22 800–33 000) individuals in 1830 to only 450 (95% PI = 200–1400) whales in the mid-1950s. Protection led to a strong recovery and the current population is estimated to be at 93% (95% PI = 73–100%) of its pre-exploitation size. The recovery of WSA humpback whales may result in large removals of their primary prey, the Antarctic krill (Euphausia superba), and has the potential to modify the community structure in their feeding grounds. Continued monitoring is needed to © 2019 The Authors. Published by the Royal Society

Royal Society Open Science

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85074710696&doi=10.1098%2frsos.190368&partnerID=40&md5=5650cda9490ad32e27a68a0f8cc532e4

Modelo poblacional Bayesiano con estructura de edad y sexo

Modelo poblacional Bayesiano con estructura de edad y sexo

Abundancia inicial, Tasa de crecimiento, Tasa de mortalidad, Tasa de crecimiento, Madurez sexual, Esperanza de vida, Tasa de inmigración, Captura anual

The whale louse Cyamus boopis is a host-specific amphipod that parasitizes humpback whales (Megaptera novaeangliae) across the world. Humpback whales from the Southern Hemisphere are currently separated into seven breeding stocks, each with its own migration route to/from Antarctic waters. The aim of this study was to determine the population structure of C. boopis from the Southern Hemisphere using cytochrome oxydase I sequences, and compare it to that of its host species found in previous studies. High haplotype and nucleotide diversities in C. boopis were observed, and the populations from western south Atlantic (WSA: Brazil + Argentina − Breeding stock A) and western south Pacific (WSP: Australia - Breeding stock E) did not show any significant difference but were differentiated from populations of eastern south Atlantic (ESA: Namibia - Breeding stock B) and the north Pacific. The genetic homogeneity between WSA and WSP populations, might reveal a higher genetic transfer within the Southern Hemisphere, since the feeding grounds of whales which are distributed throughout the circumpolar Southern Ocean could allow inter-mixing of individuals from different breeding populations during the feeding season. The present data reinforces that population dynamics of humpback whales seem more complex than stable migration routes, which could have implications for both management of the species and cultural transmissions of behaviours. © 2018 Elsevier B.V.

Iwasa-Arai T.; Serejo C.S.; Siciliano S.; Ott P.H.; Freire A.S.; Elwen S.; Crespo E.A.; Colosio A.C.; Carvalho V.L.; Rodríguez-Rey G.T.

Journal of Experimental Marine Biology and Ecology

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85046832423&doi=10.1016%2fj.jembe.2018.05.001&partnerID=40&md5=01acb1187df14638571277132e387ab7

AMOVA, Modelo de regresión linear

Varianza dentro de las poblaciones, Varianza entre las poblaciones, F-estadística

Oceáno Austral(Islas Shetland del sur, Península Antártica, Isla Georgia del sur)

Understanding Effects of Whale-Watching Vessel Noise on Humpback Whale Song in the North Pacific Coast of Colombia With Propagation Models of Masking and Acoustic Data Observations

Soundscapes with minimal anthropogenic noise sources are key for the survival and effective communication of marine mammals. The Gulf of Tribugá is part of the breeding ground for humpback whale Stock G. Currently, no large-scale infrastructure exists on the Gulf's coastline, making it an area with high biodiversity and little anthropogenic noise. Whale-watching is one of the few human activities that contributes to the soundscape. By Morro Mico, on the southern limit of the Utría Natural National Park, an Ecological Acoustic Recorder (EAR, Oceanwide Science Institute) was deployed in the Gulf to record samples of acoustic activity from October to November 2018. It recorded for 10-min intervals with 20-min lapses for a duty cycle of 33.3%. One of the common peak frequencies of humpback whale song units from these recordings was used as input to an acoustic propagation model using the parabolic equation to simulate the communication space of a humpback whale when zero, one, and two boats are present. GPS positions of theodolite data from various whale watching scenarios in the Gulf were used to inform the models. Model results indicate that humpback whale song communication space could be reduced by as much as 63% in the presence of even one whale-watching boat. The boats traveling through the Gulf are the same as those used in whale-watching, and their engine noise while passing Morro Mico coincided with song structural and temporal changes observed in the acoustic data. Combining in situ data with acoustic models can advance the understanding of the spatio-temporal acoustic reactions of whales when their vocalizations are masked by boat noise. This project serves as an approximation of how humpback whale Stock G may respond to whale-watching vessel noise in the Gulf of Tribugá. © Copyright © 2021 Rey-Baquero, Huertas-Amaya, Seger, Botero-Acosta, Luna-Acosta, Perazio, Boyle, Rosenthal and Vallejo.

Rey-Baquero M.P.; Huertas-Amaya L.V.; Seger K.D.; Botero-Acosta N.; Luna-Acosta A.; Perazio C.E.; Boyle J.K.; Rosenthal S.; Vallejo A.C.

Frontiers in Marine Science

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85103874710&doi=10.3389%2ffmars.2021.623724&partnerID=40&md5=9a6e92f06e8d8efe0b3af94deadbd398

Modelo BELLHOP, Modelo de Lombardía

Frecuencia, Batimetría, Propiedad del agua, Distribiución de la temperatura y la salinidad

Colombia(Bahía Málaga, Nuquí, Tribugá)

The waters of the Magellan Strait shelter a persistent and small feeding subpopulation of humpback whales (HWs) which is growing at a slower rate than expected, making it highly vulnerable. Despite their low abundance, the HWs represent significant consumers in this austral ecosystem. To better understand the needs of this summering subpopulation in the Magellan Strait feeding area, we estimated the biomass of prey required by HWs to meet their annual energy requirements using a velocity-dependent bioenergetic model and scaled it to two estimates of annual abundance (2011 and 2012), as well as the fraction of primary productivity required (PPR) to support that biomass of prey using a simple trophic energy transfer model. Based on a range of abundance between 75 and 101 whales, the summering subpopulation was estimated to require between 4,007 and 12,673 tons of prey under different population abundances estimates, energy needs, and residence times. These findings imply a minimum and maximum estimate ranging from 12.1 to 62.6 g C/m−2(−|-) y-1, or ∼ 6.8 to 41.5 % of net primary productivity in the feeding area to sustain the prey species directly required by HWs. Even though our estimates of prey requirements and PPR may change as new and better data become available, the results show that this small summering subpopulation requires at least a significant portion of annual phytoplankton production. © 2023 Elsevier Ltd

Progress in Oceanography

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85146428818&doi=10.1016%2fj.pocean.2023.102971&partnerID=40&md5=947aa2ac6d664ed80f5d575a7a06787c

Modelo Bioenergético, Modelo de producción primaria

Tasa de consumo máximo, Tasa de asimilación, Tasa de crecimiento, Tasa de respiración

Structured sound sequences produced by humpback whales are described in the literature as hierarchically organized songs. Despite the prevalence of such descriptions, there is no direct evidence that humpback songs are hierarchically structured. It is suggested here that songs may instead be heterarchically structured, in which case traditional approaches to analyzing songs may obscure their organizational and acoustical features. An alternative framework for characterizing patterns within songs is presented, derived from models of humpback whale sound production, that characterizes rhythmic and sequential regularities in the sound sequences produced by singing whales in terms of interacting cycles of breathing and internal air recirculation.

The Journal of the Acoustical Society of America

Journal Article

https://pubmed.ncbi.nlm.nih.gov/23145579/

Modelos de aprendizaje automatico (Red neuronal convolucional). Modelos de regresión

Modelo de Aprendizaje Automático

Numero de capas, Tamaño del filtro, Función de activación, Optimizador, Función de péredida

Pácifico Oriental, Pácifico Occidental

Machine learning algorithms are often used to model and predict animal habitat selection— the relationships between animal occurrences and habitat characteristics. For broadly distributed species, habitat selection often varies among populations and regions; thus, it would seem preferable to fit region-or population-specific models of habitat selection for more accurate inference and prediction, rather than fitting large-scale models using pooled data. However, where the aim is to make range-wide predictions, including areas for which there are no existing data or models of habitat selection, how can regional models best be combined? We propose that ensemble approaches commonly used to combine different algorithms for a single region can be reframed, treating regional habitat selection models as the candidate models. By doing so, we can incorporate regional variation when fitting predictive models of animal habitat selection across large ranges. We test this approach using satellite telemetry data from 168 humpback whales across five geographic regions in the Southern Ocean. Using random forests, we fitted a large-scale model relating humpback whale locations, versus background locations, to 10 environmental covariates, and made a circumpolar prediction of humpback whale habitat selection. We also fitted five regional models, the predictions of which we used as input features for four ensemble approaches: an unweighted ensemble, an ensemble weighted by environmental similarity in each cell, stacked generalization, and a hybrid approach wherein the environmental covariates and regional predictions were used as input features in a new model. We tested the predictive performance of these approaches on an independent validation dataset of humpback whale sightings and whaling catches. These multiregional ensemble approaches resulted in models with higher predictive performance than the circumpolar naive model. These approaches can be used to incorporate regional variation in animal habitat selection when fitting range-wide predictive models using machine learning algorithms. This can yield more accurate predictions across regions or populations of animals that may show variation in habitat selection. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

Reisinger R.R.; Friedlaender A.S.; Zerbini A.N.; Palacios D.M.; Andrews-Goff V.; Dalla Rosa L.; Double M.; Findlay K.; Garrigue C.; How J.; Jenner C.; Jenner M.-N.; Mate B.; Rosenbaum H.C.; Seakamela S.M.; Constantine R.

Remote Sensing

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85107410095&doi=10.3390%2frs13112074&partnerID=40&md5=2882f82ca3b6e20ec762bb57e185baf1

Modelo de bosque aleatorio, Modelo de bosque aleatorio

Número de árboles, Profundidad máxima del árbol, Número de variables a considerar en cada división, Temperatura del agua, Profundidad del agua, Concentración de clorofila-a, Pendiente del fondo marino, Distancia a la costa, Distancia a la plataforma continental

Whale, Whale, Everywhere: Increasing Abundance of Western South Atlantic Humpback Whales (Megaptera novaeangliae) in Their Wintering Grounds.

The western South Atlantic (WSA) humpback whale population inhabits the coast of Brazil during the breeding and calving season in winter and spring. This population was depleted to near extinction by whaling in the mid-twentieth century. Despite recent signs of recovery, increasing coastal and offshore development pose potential threats to these animals. Therefore, continuous monitoring is needed to assess population status and support conservation strategies. The aim of this work was to present ship-based line-transect estimates of abundance for humpback whales in their WSA breeding ground and to investigate potential changes in population size. Two cruises surveyed the coast of Brazil during August-September in 2008 and 2012. The area surveyed in 2008 corresponded to the currently recognized population breeding area; effort in 2012 was limited due to unfavorable weather conditions. WSA humpback whale population size in 2008 was estimated at 16,410 (CV = 0.228, 95% CI = 10,563-25,495) animals. In order to compare abundance between 2008 and 2012, estimates for the area between Salvador and Cabo Frio, which were consistently covered in the two years, were computed at 15,332 (CV = 0.243, 95% CI = 9,595-24,500) and 19,429 (CV = 0.101, 95% CI = 15,958-23,654) whales, respectively. The difference in the two estimates represents an increase of 26.7% in whale numbers in a 4-year period. The estimated abundance for 2008 is considered the most robust for the WSA humpback whale population because the ship survey conducted in that year minimized bias from various sources. Results presented here indicate that in 2008, the WSA humpback whale population was at least around 60% of its estimated pre-modern whaling abundance and that it may recover to its pre-exploitation size sooner than previously estimated.

Journal Article

https://pubmed.ncbi.nlm.nih.gov/27736958/

Modelo de Chapman, Modelo de línea recta

( # de ballenas marcadas, # de ballenas recapturadas, # de ballenas marcadas recapturadas, Probabilidad de captura, Probabilidad de supervivencia)

Brasil (Cabo de São Roque (~5°S) - Arrecife Abrolhos (~18°S), Arrecife Abrolhos (~18°S) -Cabo Frío (~23°S))

((~5°S) - (~18°S)), ( (~18°S) - (~23°S))

During the austral summer of 2006, the Projeto Baleias/Brazilian Antarctic Program (PROANTAR) conducted ship surveys for estimating whale encounter rates and abundance in Gerlache and Bransfield Straits, westward of the Antarctic Peninsula (edge between IWC Areas I and II). The encounter rate was higher in the Bransfield Strait (0.32 groups n. mile-I; 95% CI: 0.26-0.39) than in the Gerlache Strait (0.24 groups n. mile-1; 95% CI: 0.13-0.44), though the difference was not statistically evident. An abundance estimate using conventional distance sampling methods was computed only for the Bransfield Strait. The perpendicular distance data was best fitted by the half-normal model without adjustments. Derived abundance for the surveyed area was 865 humpback whales (95% CI = 656-1,141; CV= 14.13). This area represents only a small fraction of the Stock G feeding ground.

Secchi E.R.; Rosa L.D.; Kinas P.G.; Nicolette R.F.; Rufino A.M.N.; Azevedo A.F.

Journal of Cetacean Research and Management

https://www.scopus.com/inward/record.uri?eid=2-s2.0-84865357086&partnerID=40&md5=d99856d548bf79e52955f1b1b457e868

(Modelo de captura-recaptura de Jolly-Seber), (Modelo de distancia de detección consesgo de borde)

Modelo de Cormack Jolly-Seber

Párametro de supervivencia, parámetro de recaptura, parámetro de abundancia

Oceáno Austral(Península Antártica)

The cosmopolitan distribution of humpback whales (Megaptera novaeangliae) is largely driven by migrations between winter low-latitude breeding grounds and summer high-latitude feeding grounds. Southern Hemisphere humpback whales faced intensive exploitation during the whaling eras and recently show evidence of population recovery. Gene flow and shared song indicate overlap between the western (A) and eastern (B1, B2) Breeding Stocks in the South Atlantic and Indian Oceans (C1). Here, we investigated photo-identification evidence of population interchange using images of individuals photographed during boat-based tourism and research in Brazil and South Africa from 1989 to 2022. Fluke images were uploaded to Happywhale, a global digital database for marine mammal identification. Six whales were recaptured between countries from 2002 to 2021 with resighting intervals ranging from 0.76 to 12.92 years. Four whales originally photographed off Abrolhos Bank, Brazil were photographed off the Western Cape, South Africa (feeding grounds for B2). Two whales originally photographed off the Western Cape were photographed off Brazil, one traveling to the Eastern Cape in the Southwestern Indian Ocean (a migration corridor for C1) before migrating westward to Brazil. These findings photographically confirm interchange of humpback whales across the South Atlantic and Indian Oceans and the importance of international collaboration to understand population boundaries.

Ramos EA||Cheeseman T||Marcondes MCC||Olio M||Vogel A||Elwen S||de Melo THM||Facchola C||Cipolotti S||Southerland K||Findlay K||Seyboth E||McCue SA||Kotze PGH||Seakamela SM

Scientific reports

2023 Mar 21

Journal Article||Research Support, Non-U.S. Gov't

https://pubmed.ncbi.nlm.nih.gov/36944685/

(Modelo Cormack-Jolly-Seber), (Modelo de Regresión Lineal)

Modelo de Cormack Jolly-Seber

Tamaño poblacional inciial, Probabilidad de ser capturado o detectado, Probabilidad de supervivenciao reingreso, Numero de ballenas fotografiadas, Historial de recaptura, Esfuerzo de muestreo,

Acoustic metrics (AMs) aggregate the acoustic information of a complex signal into a unique number, assisting our interpretation of acoustic environments and providing a rapid and intuitive solution to analyze large passive acoustic datasets. Manual identification and characterization of intraspecific call trait variation has been largely used in a variety of sonic taxa. However, it is time consuming, relatively subjective, and measurements can suffer from low replicability. This study assesses the potential of using a combination of standardized and automatically computed AMs to train a supervised classification model, as an alternative to discrimination protocols and manual measurements to categorize humpback whale (Megaptera novaeangliae) song units from the Southern Ocean. Our random forest model successfully discriminated between the 12 humpback whale unit types (UT), achieving an average classification accuracy of 84%. UTs were further described and discussed in the context of the hierarchical structure of humpback whale song in the Southern Ocean. We show that accurate discriminant models based on relevant AM combinations provide an interesting automated solution to use for simple, rapid, and highly reproducible identification and comparison of vocalization types in humpback whale populations, with the potential to be applied to both aquatic and terrestrial contexts, on other vocal species, and over different acoustic scales.

The Journal of the Acoustical Society of America

Journal Article

https://pubmed.ncbi.nlm.nih.gov/34241469/

Modelo de mezcla lineal generalizada, PCA

Modelo de Mezcla Lineal Generalizada

Oceáno Austral(Isla Bouvet,Islas Geaorgias del Sur)

(54.°4S,3.4E), (54.2°S, 36.7°W)

Humpback whale (Megaptera novaeangliae) distribution and movements in the vicinity of South Georgia and the South Sandwich Islands Marine Protected Area

Humpback whales (Megaptera novaeangliae) are showing strong recovery from commercial whaling in the western South Atlantic. In this region, humpback whales migrate annually from their winter breeding grounds off the coast of Brazil to their summer feeding grounds near to the Polar Front, an area that includes the waters of South Georgia and the South Sandwich Islands (SGSSI). This latter region includes a Marine Protected Area (MPA), which has been developed to ensure sustainable management of fisheries, and protection of foraging predators. To date, management measures within the MPA have primarily been concerned with foraging predators that rely upon Antarctic krill, including for a number of previously over-exploited species. With humpback whales increasing in the western South Atlantic, understandingnderstanding their spatiotemporal distribution within the MPA is important as it will help inform management particularly in respect of interactions between humpback whales and the regional fishery for Antarctic krill. Here we develop habitat models from the distribution and movement patterns of 16 individuals at their high-latitude feeding grounds, south of 50°S. We show that whale habitat use varies throughout the foraging period. Upon reaching their feeding ground, whales use the area to the east of the South Sandwich Islands, moving westward into the centre of the Scotia Arc and towards South Georgia during the high summer, and then expanding back towards the east in the winter. Based on these findings, we discuss the implications for the future, including necessary research required for underpinning management. © 2022 The Authors

Bamford C.C.G.; Jackson J.A.; Kennedy A.K.; Trathan P.N.; Staniland I.J.; Andriolo A.; Bedriñana-Romano L.; Carroll E.L.; Martin S.; Zerbini A.N.

Deep-Sea Research Part II: Topical Studies in Oceanography

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85127350756&doi=10.1016%2fj.dsr2.2022.105074&partnerID=40&md5=87b7038b0aa6e57283b825e32cf20c8d

Modelo de movimiento de estado espacial, Modelo de regresión lineal generalizada

Modelo de Movimiento de Estado Espacial

Latitud, Longitud, Fecha, Estado, Covariables ambientales

Oceáno Austral (Islas Georgia del Sur, Sandwich del sur)

Oceanic waters are difficult to assess, and there are many gaps in knowledge regarding cetacean occurrence. To fill some of these gaps, this article provides important cetacean records obtained in the winter of 2010 during a dedicated expedition to collect visual and acoustic information in the Vitoria-Trindade seamounts. We observed 19 groups of cetaceans along a 1300-km search trajectory, with six species being identified: the humpback whale (Megaptera novaeangliae, N = 9 groups), the fin whale (Balaenoptera physalus, N = 1), the Antarctic minke whale (Balaenoptera bonaerensis, N = 1), the rough-toothed dolphin (Steno bredanensis, N = 1), the bottlenose dolphin (Tursiops truncatus, N = 2), and the killer whale (Orcinus orca, N = 1). Most humpback whale groups (N = 7; 78%) were observed in the Vitoria-Trindade seamounts, especially the mounts close to the Abrolhos Bank. Only one lone humpback whale was observed near Trindade Island after a search effort encompassing more than 520 km. From a total of 28 acoustic stations, humpback whale songs were only detected near the seamounts close to the Abrolhos Bank, where most groups of this species were visually detected (including a competitive group and groups with calves). The presence of humpback whales at the Trindade Island and surroundings is most likely occasional, with few sightings and low density. Finally, we observed a significant number of humpback whales along the seamounts close to the Abrolhos Bank, which may function as a breeding habitat for this species. We also added important records regarding the occurrence of cetaceans in these mounts and in the Western South Atlantic, including the endangered fin whale.

Wedekin LL||Rossi-Santos MR||Baracho C||Cypriano-Souza AL||Simoes-Lopes PC

Brazilian journal of biology = Revista brasleira de biologia

Journal Article||Research Support, Non-U.S. Gov't

https://pubmed.ncbi.nlm.nih.gov/25055095/

(Abundancia, Profundida del agua)

Brasil (Banco dos Abrolhos, Vitória Trinidade)

Humpback whales rely on acoustic communication to mediate social interactions. The distance to which these social signals propagate from the signaller defines its communication space, and therefore communication network (number of potential receivers). As humpback whales migrate along populated coastlines, they are likely to encounter noise from vessel traffic which will mask their social signals. Since no empirical data exist on baleen whale hearing, the consequences of this are usually assumed, being the modelled reduction in their communication space. Here, the communication space and network of migrating humpback whales was compared in increasing wind-dominated and vessel-dominated noise. Behavioural data on their social interactions were then used to inform these models. In typical wind noise, a signaller's communication space was estimated to extend to 4 km, which agreed with the maximum separation distance between groups that socially interacted. An increase in vessel noise reduced the modelled communication area, along with a significant reduction in group social interactions, probably due to a reduction in their communication network. However, signal masking did not fully explain this change in social behaviour, implying there was also an additional effect of the physical presence of the vessel on signaller and receiver behaviour. Though these observed changes in communication space and social behaviour were likely to be short term and localized, an increase in vessel activity due to tourism and coastal population growth may cause more sustained changes along the humpback whale migration paths.

Royal Society open science

Journal Article

https://pubmed.ncbi.nlm.nih.gov/31827838/

Tasa de llamada de las BJ, Ruido de los barcos, Profundidad del agua, Temperatura del agua, Velocidad del sonido

Investigating the influence of coastal development on marine environments is a priority to maintain healthy seas. Cetaceans are top predators, keystone and umbrella species and thus are good candidate models to evaluate the extent of anthropogenic impacts on coastal habitats. We employed a generalized linear model with spatial eigenvector mapping (SEV-GLM) to understand the influence of environmental and anthropogenic activities on migrant (humpback whale Megaptera novaeangliae) and non-migrant (Bryde’s whale Balaenoptera brydei and common bottlenose dolphin Tursiops truncatus) cetacean habitat use off Cabo Frio, Rio de Janeiro, Brazil. We hypothesized that both environmental and anthropogenic activities influence their habitat use. Data were collected during 118 boat trips between December 2010 and June 2014. The best SEV-GLM predicted humpback whales would increase linearly with distance to coast, with minimum sea surface temperature (SST) around 19.4−19.8°C and maximum SST around 25.5−26°C, with low variations in chlorophyll a (chl a) concentrations. The model also predicted that humpback whales would occur up to 10 km from diving areas, increasing linearly with distance to fishing grounds. The best non-migrant cetacean SEV-GLM predicted that they would occur more frequently around depths from 30−60 m, increasing with low SST and high chl a concentration. For the anthropogenic component, the model predicted that non-migrant cetaceans would occur up to 10 km from fishing grounds. Our study modeled the influence of anthropogenic activities on cetaceans, and indicates specific priority areas for cetacean conservation, contributing at a local and national scale. © Inter-Research 2019

Marine Ecology Progress Series

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85065479024&doi=10.3354%2fmeps12937&partnerID=40&md5=620bb3650c5e201ce3c7778e53e5c442

Modelos de regresion lineal generalizada, PCA

Modelo de Regresión Lineal Generalizado

Profundidad del agua, Temperatura del agua, Salinidad, Clorofila-a, Cobertura de nubes, Distancia a la costa, Densidad del tráfico marino

Humpback whales (Megaptera novaeangliae) perform seasonal migrations from high latitude feeding grounds to low latitude breeding and calving grounds. Feeding grounds at polar regions are currently experiencing major ecosystem modifications, therefore, quantitatively assessing species responses to habitat characteristics is crucial for understanding how whales might respond to such modifications. We analyzed satellite telemetry data from 22 individual humpback whales in the Southwest Atlantic Ocean (SWA). Tagging effort was divided in two periods, 2003-2012 and 2016-2019. Correlations between whale's movement parameters and environmental variables were used as proxy for inferring behavioral responses to environmental variation. Two versions of a covariate-driven continuous-time correlated random-walk state-space model, were fitted to the data: i) Population-level models (P-models), which assess correlation parameters pooling data across all individuals or groups, and ii) individual-level models (I-models), fitted independently for each tagged whale. Area of Restricted Search behavior (slower and less directionally persistent movement, ARS) was concentrated at cold waters south of the Polar Front (~ 50 degrees S). The best model showed that ARS was expected to occur in coastal areas and over ridges and seamounts. Ice coverage during August of each year was a consistent predictor of ARS across models. Wind stress curl and sea surface temperature anomalies were also correlated with movement parameters but elicited larger inter-individual variation. I-models were consistent with P-models' predictions for the case of females accompanied by calves (mothers), while males and those of undetermined sex (males +) presented more variability as a group. Spatial predictions of humpback whale behavioral responses showed that feeding grounds for this population are concentrated in the complex system of islands, ridges, and rises of the Scotia Sea and the northern Weddell Ridge. More southernly incursions were observed in recent years, suggesting a potential response to increased temperature and large ice coverage reduction observed in the late 2010s. Although, small sample size and differences in tracking duration precluded appropriately testing predictions for such a distributional shift, our modelling framework showed the efficiency of borrowing statistical strength during data pooling, while pinpointing where more complexity should be added in the future as additional data become available.

Scientific reports

Journal Article||Research Support, Non-U.S. Gov't

https://pubmed.ncbi.nlm.nih.gov/35523932/

Regresión Lineal Generalizada,Mezcla de Distribución Normal

Modelo de Regresión Lineal Generalizado

(Latitud y longitud de las ballenas, Cobertura del hielo marino, Temperatura del agua superficial, Curvatura del viento, Batimetría, Sexo, Año, Individuo)

Brasil(Isla de Santa Catarina), Oceáno Austral(Frente Polar, Mar de Scotia, norte dela Dorsal del Weddell, Península Valdés)

The social structure of humpback whales in their tropical wintering grounds is very fluid. To date, no information has been published for cases in which two whales were both satellite-tagged while in association. Here, we report the movements of four humpback whale pairs tagged together off the coast of Brazil. Fieldwork and satellite tagging of humpback whales was conducted between 2003 and 2008 along the eastern coast of Brazil, between 20°S and 8°S. Movement was monitored while whales were still in their breeding ground. A switching state space model was applied to the filtered data of each humpback whale to standardize telemetry data and allow direct comparison of each individual track. GIS was used to plot model-predicted locations and to visually compare animal movements. The results confirm the short-lived nature of associations between breeding humpback whales, and shows that individuals differ widely in their movements. © 2014 Sociedade Brasileira de Zoologia.

Andriolo A.; Zerbini A.N.; Moreira S.; Pizzorno J.L.; Danilewicz D.; Maia Y.G.; Mamede N.; de Castro F.R.; Clapham P.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-84901039976&doi=10.1590%2fS1984-46702014000200001&partnerID=40&md5=8941ac4da1a1c9a2683f6f9a73c00656

Modelo de regresión lineal generalizada, Modelo de análisis de supervivencia

Modelo de Regresión Lineal Generalizado

Probabilidad de que las ballenas permanezcan juntas, Etiqueta, Distancia, Sexo, Comportamiento, Dia del año

Humpback whales (Megaptera novaeangliae) breeding off Mozambique and Ecuador show geographic variation of persistent organic pollutants and isotopic niches.

Humpback whales (Megaptera novaeangliae) from the Southern Hemisphere carry information on persistent organic pollutants (POPs) from their feeding zones in Antarctica to their breeding grounds, making this species a sentinel of contaminants accumulation in the Southern Ocean. This study aimed to evaluate driving factors, namely feeding areas, trophic level, and sex, affecting POP concentrations in the blubber of humpback whales breeding off Mozambique and off Ecuador. Biopsies of free-ranging humpback whales including blubber and skin were collected in 2014 and 2015 from Ecuador (n = 59) and in 2017 from Mozambique (n = 89). In both populations, HCB was the major contaminant followed by DDTs > CHLs > PCBs > HCHs > PBDEs. POP concentrations were significantly higher in males compared to females. HCB, DDTs, HCHs and PBDEs were significantly different between whales from the Mozambique population and the Ecuador population. Sex and feeding habits were important driving factors accounting for POP concentrations in Ecuador whales. The whales from our study had some of the lowest POP concentrations measured for humpback whales in the world. These whales fed predominantly on krill as reflected from the low delta(13)C and delta(15)N values measured in the skin. However, the isotopic niches of whales from Mozambique and Ecuador did not overlap indicating that the two populations are feeding in different areas of the Southern Ocean.

Remili A||Gallego P||Pinzone M||Castro C||Jauniaux T||Garigliany MM||Malarvannan G||Covaci A||Das K

Environmental pollution (Barking, Essex : 1987)

Journal Article

https://pubmed.ncbi.nlm.nih.gov/33254700/

(Modelo Líneal Mixto), (Análisis de Mezcla Isótopica)

(Sexo, Zona Geografica, Nivel Trofico)

Ecuador(Isla de la plata, Parque Nacional Machalilla)

(01°23'S 81°03'W), (01°45'S 80°50'W)

Mobilization of persistent organic pollutants in humpback whales: Insights from feeding areas in the Antarctic peninsula and Strait of Magellan to migration, breeding, and calving grounds along the Brazilian coast

Southern Hemisphere Megaptera novaeangliae undertake the longest migration, which reflect their exposure to lipophilic contaminants. To assess these changes, persistent organic pollutants were analyzed in blubber samples of humpback whales from three regions: the Antarctic Peninsula (n = 46), the Strait of Magellan, Chile (n = 22), and the Brazilian coast (n = 38). The similarity in PCB and HCB levels between individuals from feeding grounds and breeding grounds suggests contamination during feeding. The whales around the Antarctic Peninsula exhibited a predominance of tetrachlorobiphenyl PCBs. Whales feeding in the Strait of Magellan showed a slight prevalence of 5Cl biphenyls, likely due to their consumption of subantarctic krill species as well as small fishes potentially contaminated by industrial activities in Chile. The dominance of 5-6Cl congeners in whales in Brazil, may be attributed to the extreme physiological changes during fasting when whales utilize blubber reserves and metabolize lighter congeners, or transfer them to their calves. © 2023 Elsevier Ltd

da Silva J.; Taniguchi S.; Colabuono F.I.; Leonel J.; Rosa L.D.; Secchi E.R.; Borges J.C.G.; Siciliano S.; Acevedo J.; Aguayo-Lobo A.; Baldassin P.; Montone R.C.; Lourenço R.A.

Marine Pollution Bulletin

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85169001809&doi=10.1016%2fj.marpolbul.2023.115448&partnerID=40&md5=6f41014d68fce67fbae3c19a7f93fc52

Modelo lineal mixto, Modelo de isótopos estables

Intercepto, Efecto del sexo, Efecto d la clase de edad, Efecto del área de estudio, Efecto aleatorio

Brasil, Chiles( Estrecho de Magallanes),Oceáno Austral(Península Antártica)

Humpback whales wintering in tropical waters along the Atlantic and Pacific coasts of the South American continent are thought to represent distinct populations or “stocks.” Here we present the first analysis of genetic differentiation and estimates of gene flow between these breeding stocks, based on both mitochondrial DNA (mtDNA) control region sequences (465 bp) and 16 microsatellite loci from samples collected off Brazil (n = 277) and Colombia (n = 148), as well as feeding areas near the western Antarctic Peninsula (n = 86). We found significant differentiation between Brazilian and Colombian breeding grounds at both mtDNA (FST = 0.058) and microsatellite (FST = 0.011) markers and corroborated previous studies showing genetic similarity between humpbacks from Colombia and those from Antarctic Peninsula feeding areas. Estimates of long-term gene flow between Brazil and Colombia were low to moderate, asymmetrical, and mostly mediated by males. Assignment procedures detected some cases of interchange and individuals of admixed ancestry between breeding grounds, indicating limited mixing of individuals between these stocks. Overall, results highlight the differentiation of humpback whale breeding populations with adjacent feeding grounds. This appears to be a remarkable example of fidelity to seasonal habitat in the absence of any contemporary barriers. © 2016 Society for Marine Mammalogy

Cypriano-Souza A.L.; Engel M.H.; Caballero S.; Olavarría C.; Flórez-González L.; Capella J.; Steel D.; Sremba A.; Aguayo A.; Thiele D.; Baker C.S.; Bonatto S.L.

Marine Mammal Science

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85002831767&doi=10.1111%2fmms.12378&partnerID=40&md5=64713eb49ae6eeb6d52db6f12041cf70

AMOVA, F-estadísticas, Distancias genéticas

Pacífico suroriental, Atlántico Sur Occidental

Humpback whales (Megaptera novaeangliae) undertake seasonal migrations between low-latitude breeding grounds in winter and high-latitude feeding grounds in summer. In the Southern Hemisphere, seven primary breeding stocks have been identified based on tropical distribution between which there is limited gene flow. In the summer, these stocks are distributed among six Management Areas (Areas I–VI) defined by the International Whaling Commission in the Southern Ocean feeding grounds. The extent to which different breeding stocks mix on these feeding grounds, and the genetic structure and relationships between them, remains unclear. This uncertainty has led to the review and development of hypotheses to refine stock boundaries in the Antarctic. This study is the first to analyse the circumpolar genetic structure of humpback whales in their feeding aggregations. Sequences of the mitochondrial control region and microsatellite DNA variation were obtained for 399 humpback whale samples, obtained within the six Antarctic Management Areas. Results from both sets of markers were consistent in showing a complex pattern of differentiation between feeding aggregations across the feeding range. Management Area I surrounding the Antarctic Peninsula, associated with Breeding Stock G in the south-eastern Pacific Ocean, was highly differentiated from all other feeding aggregations, suggesting strong fidelity towards the Peninsula. In contrast, adjacent feeding grounds showed much lower levels or no significant differentiation, suggesting interchange of individuals and overlap of breeding stocks on their summer feeding grounds. These results have important implications from the perspective of conservation and management, as failure to recognize overlapping distributions may result in misleading estimates of abundance and growth trends of particular recovering humpback whale populations. © 2016, Springer-Verlag Berlin Heidelberg.

Amaral A.R.; Loo J.; Jaris H.; Olavarria C.; Thiele D.; Ensor P.; Aguayo A.; Rosenbaum H.C.

Marine Biology

https://www.scopus.com/inward/record.uri?eid=2-s2.0-84971658614&doi=10.1007%2fs00227-016-2904-0&partnerID=40&md5=db536ce756b43d6f7bfd50371c684035

Modelo de migración Bayesiano, Modelos de coalescencia, AMOVA

Modelo Bayesiano de Migración

Tasas de migración, Tamaños efectivos poblacionales, Tiempos de divergencia

Humpback whale males are known to sing on their low-latitude breeding grounds, but it is well established that songs are also commonly produced 'off-season' on the feeding grounds or during migration. This opens exciting opportunities to investigate migratory aggregations, study humpback whale behavioral plasticity and potentially even assign individual singers to specific breeding grounds. In this study, we analyzed passive acoustic data from 13 recording positions and multiple years (2011-2018) within the Atlantic sector of the Southern Ocean (ASSO). Humpback whale song was detected at nine recording positions in five years. Most songs were recorded in May, austral fall, coinciding with the rapid increase in sea ice concentration at most recording positions. The spatio-temporal pattern in humpback whale singing activity on Southern Ocean feeding grounds is most likely shaped by local prey availability and humpback whale migratory strategies. Furthermore, the comparative analyses of song structures clearly show a differentiation of two song groups, of which one was solely recorded at the western edge of the ASSO and the other song group was recorded throughout the ASSO. This new finding suggests a common feeding ground occupation by multiple humpback whale populations in the ASSO, allowing for cultural and potentially even genetic exchange among populations.

Schall E||Thomisch K||Boebel O||Gerlach G||Mangia Woods S||T Roca I||Van Opzeeland I

Scientific reports

2021 Sep 22

Journal Article||Research Support, Non-U.S. Gov't

https://pubmed.ncbi.nlm.nih.gov/34552129/

Modelo de análisis de canto,Modelos de mezclA. Modelo de regresión lógistica

(Frecuencia, Duración, Estructura, Timbre)

Effective population size and the genetic consequences of commercial whaling on the humpback whales (Megaptera novaeangliae) from southwestern Atlantic ocean

Genotypes of 10 microsatellite loci of 420 humpback whales from the Southwestern Atlantic Ocean population were used to estimate for the first time its contemporary effective (Ne) and census (Nc) population sizes and to test the genetic effect of commercial whaling. The results are in agreement with our previous studies that found high genetic diversity for this breeding population. Using an approximate Bayesian computation approach, the scenario of constant Ne was significantly supported over scenarios with moderate to strong size changes during the commercial whaling period. The previous generation Nc (Ne multiplied by 3.6), which should corresponds to the years between around 1980 and 1990, was estimated between ~2,600 and 6,800 whales (point estimate ~4,000), and is broadly compatible with the recent abundance surveys extrapolated to the past using a growth rate of 7.4% per annum. The long-termNc in the constant scenario (point estimate ~15,000) was broadly compatible (considering the confidence interval) with pre-whaling catch records estimates (point estimate ~25,000). Overall, our results shown that the Southwestern Atlantic Ocean humpback whale population is genetically very diverse and resisted well to the strong population reduction during commercial whaling. © 2018, Sociedade Brasileira de Genética.

Genetics and Molecular Biology

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85045520941&doi=10.1590%2f1678-4685-gmb-2017-0052&partnerID=40&md5=4e328adc98547a30b9856a6ba7e1074b

Modelo de Coalescencia con crecimiento exponencial, Modelo de deriva genética, Modelo isla-continente

Modelo de Coalescencia con Crecimiento Exponencial

Tamaño efectivo de la población, Tamaño censal de la población, Tasa de crecimiento, Tiempo de generación, Tasa de mutación, Número de loci

Brasi(Banco de Abrolhos, Espiritu Santo)

Humpback whales were hunted almost to extinction in the 20th century, providing an opportunity to measure their post-exploitation population growth rates. Variation in growth rates may be related to many factors, and little work has been done to understand the differences among populations. First, we provided an estimate of the growth rate for the Brazilian breeding stock of humpback whales using models that consider imperfect detection applied to a long-term and broad-scale dataset collected through systematic aerial surveys. Then, a review of the literature on the population growth rates of this species worldwide and a meta-analysis were conducted to explore the differences in growth rates and their determinants. A finite growth rate of 12% yr-1 (95% CI = 8-16%; CV = 17%) for the population wintering in Brazil was estimated from aerial surveys conducted from 2002 to 2011 and may be regarded as an empirical estimate of its intrinsic growth rate. The meta-analysis shows that there are geographical differences in growth rates, with substantial heterogeneity among studies. Growth rates of populations in the Northern Hemisphere are predicted to be lower than those in the Southern Hemisphere. The geographical differences in population parameters may be explained by spatial variability in productivity and prey availability, human impact and distinct hunting histories. Moreover, the differences in population growth rates are linked to genetic variability, with populations with higher haplotype diversity growing at faster rates. Long-term studies on dynamics of baleen whale populations reduced by whaling are invaluable to investigate the population growth and regulation of these cetaceans. © Inter-Research 2017.

Wedekin L.L.; Engel M.H.; Andriolo A.; Prado P.I.; Zerbini A.N.; Marcondes M.M.C.; Kinas P.G.; Simões-Lopes P.C.

Marine Ecology Progress Series

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85025688399&doi=10.3354%2fmeps12211&partnerID=40&md5=a168962a44a41d36d64ab9b243719b47

Modelo Jolly-Seber, Modelo Brownie-Robson, Modelo de regresión lineal

Tasa de supervivencia, Tasa de captura, Tasa de reclutamiento

For many biological investigations, groups of individuals are genetically sampled from several geographic locations. These sampling locations often do not reflect the genetic population structure. We describe a framework using marginal likelihoods to compare and order structured population models, such as testing whether the sampling locations belong to the same randomly mating population or comparing unidirectional and multidirectional gene flow models. In the context of inferences employing Markov chain Monte Carlo methods, the accuracy of the marginal likelihoods depends heavily on the approximation method used to calculate the marginal likelihood. Two methods, modified thermodynamic integration and a stabilized harmonic mean estimator, are compared. With finite Markov chain Monte Carlo run lengths, the harmonic mean estimator may not be consistent. Thermodynamic integration, in contrast, delivers considerably better estimates of the marginal likelihood. The choice of prior distributions does not influence the order and choice of the better models when the marginal likelihood is estimated using thermodynamic integration, whereas with the harmonic mean estimator the influence of the prior is pronounced and the order of the models changes. The approximation of marginal likelihood using thermodynamic integration in MIGRATE allows the evaluation of complex population genetic models, not only of whether sampling locations belong to a single panmictic population, but also of competing complex structured population models.

Journal Article||Research Support, N.I.H., Extramural||Research Support, U.S. Gov't, Non-P.H.S.

https://pubmed.ncbi.nlm.nih.gov/20176979/

Modelo de Panmixia, Modelo de aislamiento por distancia, Modelo de migración

Población ancestral, Coeficientes de endogamia, Tasas de migración,

Southem Hemisphere humpback whales (Megaptera novaeangliae) migrate from wintering grounds in tropical latitudes to feeding areas in the Antarctic Ocean. In 2003 and 2005, satellite transmitters were deployed on humpback whales on their wintering grounds off the eastern coast of South America (Breeding Stock A). Seven whales were tracked for a period of 16 to 205 days travelling between 902 and 7,258km. The tracks of these whales provided partial or full information on the migratory schedule, migration routes and location of the feeding ground in the Southern Oceans. Whales departed from the coast of Brazil from late October to late December between 20" and 25°S and gradually moved away from the South American coast as they moved towards high latitudes. They followed a somewhat direct, linear path, with an approximate geographic heading of 170*. Satellite telemetry data indicated that the migratory corridors are restricted to a relatively narrow (~500-800km) strip in the South Atlantic Ocean. Migration speed to the feeding grounds averaged 80.2km/day and lasted from 40-58 days. Four individuals arrived at the feeding ground located to the north of the South Sandwich Islands, where they were tracked up to 102 days. Movements in this area were erratic at a mean travelling speed of 22.3km/day. Satellite telemetry data indicate that the main feeding grounds for the population wintering off eastern South America lie between 22'W and 33'W and in the southern South Atlantic Ocean south of the Antarctic Convergence but north of 60°S. This is only partially consistent with the currently proposed stock boundaries for this population on the feeding grounds.

Zerbini A.N.; Andriolo A.; Heide-Jorgensen M.P.; Moreira S.C.; Pizzorno J.L.; Maia Y.G.; Vanblaricom G.R.; Demaster D.P.

Journal of Cetacean Research and Management

https://www.scopus.com/inward/record.uri?eid=2-s2.0-84863748793&partnerID=40&md5=7b495093c6e1a388d136926f52f22c64

(Modelo de regresión lineal generalizada),(Modelos de PCA), (Modelos de autocorrelación espacial)

Modelo de Regresión Lineal Generalizado

(,Dirección del movimiento de las ballenas, Temperatura del agua, Profundidad del óceano, Topografía del fondo marino, Año, Sexo, Estado reproductivo, Autocorrelación espacial)

Brasil(Banco de Abrolhos, Vitória), Oceáno Austral(Georgia del sur, islas Sandwich del sur)

The past six years have been marked by some of the most dramatic climatic events observed in the Antarctic region in recent history, commencing with the 2017 sea-ice extreme low. The Humpback Whale Sentinel Programme is a circum-polar biomonitoring program for long term surveillance of the Antarctic sea-ice ecosystem. It has previously signalled the extreme La Nina event of 2010/11, and it was therefore of interest to assess the capacity of existing biomonitoring measures under the program to detect the impacts of 2017 anomalous climatic events. Six ecophysiological markers of population adiposity, diet, and fecundity were targeted, as well as calf and juvenile mortality via stranding records. All indicators, with the exception of bulk stable isotope dietary tracers, indicated a negative trend in 2017, whilst C and N bulk stable isotopes appeared to indicate a lag phase resulting from the anomalous year. The collation of multiple biochemical, chemical, and observational lines of evidence via a single biomonitoring platform provides comprehensive information for evidence-led policy in the Antarctic and Southern Ocean region.

Bengtson Nash SM||Grobeta J||Castrillon J||Casa MV||Luche GD||Meager J||Ghosh R||Eggebo J||Nizzetto PB

The Science of the total environment

2023 Aug 20

Journal Article

https://pubmed.ncbi.nlm.nih.gov/37178847/

(Modelos mixtos lineales),(Modelo de Regresión Lineal), (PCA)

(Salud de la ballena, Esperos de la capa blubber, Niveles de cortisol, Niveles de testosterona, Estado de gestación, Tamañao de las crías, Condición Corporal, Cantidad de hielo marino, Edad, Sexo, Dieta)

Oceáno Austral(Península Antártica, Isla Decepción, Caleta Potter, Bahía Paraíso)

The Atlantic sector of the Southern Ocean (ASSO) has one of the highest densities of Antarctic krill (Euphausia superba) compared to other polar and subpolar regions, which attracts migratory baleen whale species to aggregate in this area for feeding. Humpback whales (Megaptera novaeangliae) also sing extensively while on the Southern Ocean feeding grounds which allows for the exploration of song similarity between feeding grounds and breeding populations which helps to understand population mixing. The results of comparative song analyses between the ASSO and the Ecuadorian and Brazilian breeding populations and recordings from the Chilean, South African and Namibian migration routes/mid-latitude feeding grounds revealed that individuals from at least three humpback whale breeding populations most likely migrate to shared feeding grounds in the ASSO. Humpback whales from different populations potentially mix at different times (i.e., years) at feeding hotspots in variable locations. The ASSO seems to provide sufficient prey resources and seems to present an important area for both cultural and maybe even genetic exchange between populations supporting the maintenance of large gene pools. Assuming that multi-population feeding hotspots are also suitable habitat for krill and other krill-dependent predators, these areas in the ASSO should be carefully managed integrating population, ecosystem and fisheries management.

Schall E||Djokic D||Ross-Marsh EC||Ona J||Denkinger J||Ernesto Baumgarten J||Rodrigues Padovese L||Rossi-Santos MR||Carvalho Goncalves MI||Sousa-Lima R||Hucke-Gaete R||Elwen S||Buchan S||Gridley T||Van Opzeeland I

Scientific reports

2022 Aug 17

Journal Article||Research Support, Non-U.S. Gov't

https://pubmed.ncbi.nlm.nih.gov/35978069/

Modelo de análisis de canto,PCA, Análisis discriminante lineal, Modelos de mezcla gaussiana

(Frecuencia, Duración, Estructura, Timbre)

The Southwestern Atlantic Ocean humpback whales wintering ground (breeding stock A) are distributed along the Brazilian coast (5-23 degrees S), and their main mating and calving ground is in the Abrolhos Bank. We investigated genetic diversity, population structure, and relatedness of individuals sampled from the entire Southwest Atlantic humpback whale population. A total of 275 individuals sampled from 2 subregions (Abrolhos Bank, n = 229 and Praia do Forte, n = 46) were screened for 9 microsatellite loci. This population showed a high level of allelic diversity (A = 12.1) and a high mean observed heterozygosity (H(O) = 0.733). No signal of significant genetic bottleneck was detected in accordance with the mitochondrial DNA data. We find no evidence of temporal (between years) genetic structure as well as no genetic differentiation between whales from the 2 subregions of the Brazilian breeding ground. We observed that the proportion of males and females in this population was approximately 1:1, which differs from the male-biased sex ratio observed in other breeding grounds. The data obtained through this study provided no evidence of kinship associations within social groups. Finally, a female sampled off South Georgia Islands showed a putative parent-offspring relationship with a female off Abrolhos Bank, supporting the migratory link between these 2 areas.

The Journal of heredity

2010 Mar-Apr

Journal Article||Research Support, Non-U.S. Gov't

https://pubmed.ncbi.nlm.nih.gov/19889721/

(Diversidad de Nei, F-estadísticas, AMOVA, BAYESCAN, Maximum Likelyhood, Coalescencia)

Brasil(Banco de Abrolhos, Praia do Forte)

(16°40´- 19°30´S, 37°25´ - 39°45´W)