Monitoring Protocol of Northeastern Beach Tiger Beetle

The Northeastern Beach Tiger Beetle (Cicindella dorsalis) is a sand colored, winged insect ranging from 13-15.5 mm in length. This beetle has a two year life cycle, consisting of the stages of egg, larva, and adult (Northeastern Beach Tiger Beetle, 2011.) The majority of the beetles life is spent in the larva stage that is divided into three stages. Eggs are laid between the months of June to August and reach the first stage of larva by September. After a period of 1.5 years, the larva emerge as winged adults. Northeaster Tiger Beetles live on the upper portion of sandy beaches where they are able to burrow into the sand to lay eggs without the threat of waves. These beetles are highly active during the warmer months that allow for predation but remain dormant during the colder winter months (New, 2010). The Tiger Beetle survives off of lice, fleas and ants found on the beach. As of 2014, the Northeastern Beach Tiger Beetle is a federally threatened species. This beetle once occupied the eastern beach shores from Massachusetts down through Virginia. Now it is endangered within Massachusetts and New York and threatened in Maryland and Virginia.

Major threats to the northeastern beach tiger beetle include loss of habitat and human interaction with habitat. Tiger beetle spends the majority of their lifecycle in the larval stage burrowed in sand for 18 months. The length of time spent in the larval stage makes the tiger beetle vulnerable to dramatic changes in shoreline (New, 2010). The shoreline at Bluff Point, Virginia is receding each year, decreasing available habitat and killing tiger beetle larvae that burrow into the sand.  The shoreline at Bluff Point, Virginia is eroding each year, decreasing available habitat and preventing larval growth and killing already present larvae (Omland, 2002). Human impact such as trampling habitat and garbage are negatively affecting the larval stages and mating season by changing the physical habitat and disturbing the environment and available nutrients.

There have been semi-successful conservation effects for other tiger beetles, where locals put up fences during June and July mating season. Putting up fences on the beach during summer months has a potential of improving tiger beetle population by limiting beach usage and helping limit disturbances to the tiger beetle habitat (Omland, 2002).  

Delineate species recovery strategy

We want to implement practices to try and conserve beaches, especially in current range but also in future hopeful range.  We will focus on the areas where the Northeastern Tiger Beetle is currently, but also on nearby areas where the beetles have become extirpated in hopes that these populations will re-emerge either naturally or through re-introduction programs.  The plans at all beaches will be similar in a general sense, but human traffic and impact will be assessed on a beach by beach basis.  We will monitor adult beetles post release through standard survey techniques, but also monitor human impacts and the affect these impacts may be having on beetle eggs and larvae.  These reintroduced beetles will come from beaches where the beetles are not in immediate danger of extirpation, or after our CAP plan has been implemented on these beaches.  Re-introduction will occur over time with multiple reintroductions taking place so as to create genetic diversity within the new populations and try to limit the founder effect.

After specific beaches and human impacts are identified, a few practices will be implemented to protect beetle populations from human impact.  These include limiting beach usage through fencing, limiting beach usage by requesting private beach owners to limit impact, or potentially paying beach owners to limit impact.  Another factor limiting beetle populations is beach loss through erosion.  A few practices such as sand nourishment, windbreak fences, wave breakers, and establishing healthy beach ecosystems will be implemented in order to try and conserve beach.  Sand nourishment is the practice of translocating sand from a healthy beach and placing it in an area where beach is being eroded (Fenster et al, 2005.)  

Sampling design

MONITORING PROTOCOL

Our sampling design will include pitfall traps and point counts. The pitfall traps will allow us to perform a capture and recapture method of estimating population. Point counts will allow us to have a backup method of estimating the population of Northeastern Beach Tiger Beetle. We chose these methods of collection and population estimation because they are very common among entomologists. Our area of interest is Bluff Point, Va and we are going to look at all strips of beach that are above sea level at high tide and show signs of Northeastern Tiger Beetle. All areas of continuous beach will be considered a population. Areas of beach that are disconnected or separate from the other beaches, but are in the same area will be treated as part of the metapopulation. The pitfall traps will be five meters away from the high tide boundary and at least ten meters away from other pitfall traps. This method should create a line that runs the length of the beach and the number of pitfall traps used will be determined by the length of the beach. Once the pitfall traps are set, point counts will be taken at random positions along the beach for twenty minutes. Ideally, the design will be replicated twice a year; once before mating season (around April) and once after mating season (around August). This process should be replicated as many times as possible on any of the previously known locations of the Northeastern Beach Tiger Beetle (“Northeastern Tiger Beach Beetle,”). The level of change between beaches will be measured by the population density of beetles per hectare.

         To monitor the Northeastern Tiger Beetle, pitfall traps will need to be set up at the beginning and end of mating season, which is the first week of June and the last week of August. First, we will need to obtain permits from the Virginia Department of Game and Inland Fisheries that allow for scientific research on endangered species and permission to survey on their properties. Next, we will need to determine the placement of each pitfall site. At each site, five-gallon buckets will be buried in the sand at three sites along Bluff Point. Once buckets are buried, deceased anthropoids will be placed above the buckets to bait the Northeastern Beach Tiger Beetles to the designated sites. Buckets will be left in the sand for a 24-hour period to allow for burrowing. The buckets will then be removed from the sand and placed in a cooler to allow the beetles to decrease activity. Next, the beetles will be taken from the cooler and gently unloaded into a trough where they will be counted and marked. The beetles will be marked with nontoxic oil based paint in neutral colors. Once the beetles are marked, they will be released back into the population. At each time of collection a different marking will be used to determine recapture and each site will use a different designated color to determine if migration is occurring. We will also perform point and count procedures to determine a rough estimate of the population that we can use to compare with the pitfall data. This will be done by counting all Northeastern Tiger Beetles seen within the site during five minute intervals.

        The data collected from pitfall traps and point count survey will be use to determine the population size and density of northeastern tiger beetles translocated to Bluff Point shoreline. The area of each site or pitfall trap will be used to determine the density of population size on the shore and the success of translocation of beetles. Beetle population will be measured twice during the season; early June and late August. This will dictate the population growth between pre-mating season and post-mating season, which will be used to determine the growth rate of tiger beetles in a single year and predict rate of growth on a population at an individual site.

Table 1. Beetle count at different location on the shore using different population survey methods.

To record data, the pitfall traps will be removed and the sand will be shifted through and the number of adult beetles will be recorded in a write-in-the-rain notebook for each site and transferred to an excel spreadsheet. After setting up pitfall traps, a point count survey will be taken and recorded in a write-in-the-rain notebook and transferred into an excel spreadsheet.

For long term analysis, metadata procedure will remain constant and a graph of population density growth over long term time will be produced. All data in notebooks and excel spreadsheets will be labeled and organized. The excel spreadsheets will be backed up on each person’s computer.  

 Both people would be responsible for not harming the endangered northeastern tiger beetle and maintaining the condition of the shoreline where pitfall traps were placed. The researchers performing the experiment twice a year would need a biology background, field work experience, able to identify northeastern tiger beetles, and proficient in using basic tools.  The training procedure would include; how to assemble a pitfall trap using all the necessary tools, how to handle northeastern tiger beetles, and properly point counting beetles.

In early June, 2 people will monitor tiger beetles, maintain signs, and windbreak fences. The two volunteers will set up pitfall traps and do a point count survey of the beetles. The total time for performing the experiment and maintenance of signs and fences will be 16 hours by each person. In late August, the same 16 hour procedure will occur.  

        For point counting, a clicker and a write-in-the-rain notebook would be the only required equipment; however, the pitfall trap would need more material. The researchers would need a write-in-the-rain notebook, deep buckets, shovels, and a workstation to sift through the sand. Sign and windbreak fence maintenance would require basic tools like hammers, wrenches, screws, and nails.  

        The budget will cover cost of materials needed and travel expenses.  The budget is estimated to be close to $1,000 initially, with the potential for increase when area of habitat increases. Along with monetary compensation for gas and vehicle usage amounting to approximately $300 annually. The budget for this plan will likely be covered through different government agencies such as the EPA or US Fish and Wildlife Service.  Practices and monitoring will likely be performed by either government workers or volunteers from conservation groups or universities.

Literature cited:

"Tiger Beetles of the United States." Tiger Beetles of Virginia. Northern Prairie Wildlife Research Center, 2 Feb. 2013. Web. 22 Oct. 2014.

T.R., New. "Beetles in Conservation." (2010): 237. Print.

Taboada, Angela, Henrik Von Wehrden, and Thorsten Assmann. "Integrating Life Stages into Ecological Niche Models: A Case Study on Tiger Beetles." PLoS ONE 8.7 (2013): 1-13. Print.

“Northeastern Tiger Beach Beetle,” U.S. Fish and Wildlife, September, 2011. Web. 22 Oct. 2014

Fenster, Miachael S., Knisley, C. Barry, Reed, Christopher T.; “Habitat Preference and the Effects of Beach Nourishment on the Federally Threatened Northeastern Beach Tiger Beetle, Cicindela dorsalis dorsalis: Western Shore, Chesapeake Bay, Virginia,” Journal of Coastal Research, 2006, Web. Oct 22, 2014

Brust, Mathew L., C. Barry Knisley, Stephen M. Spomer, and Kentaro Miwa. "Observations of Oviposition Behavior Among North American Tiger Beetle (Coleoptera: Carabidae: Cicindelinae) Species and Notes on Mass Rearing." The Coleopterists Bulletin 66.4 (2012): 309-14. Print.

Omland, Kristian Shawn. "Larval Habitat and Reintroduction Site Selection for Cicindela Puritana in Connecticut." Northeastern Naturalist 9.4 (2002): 433. Print.