Status Determination Criteria and Optimum Yield for Reef Fish (Responses)
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TimestampEnter your full nameemail addressCity, State, Zip CodeCheck all that applyComments
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7/28/2017 11:44:07Testtest@gulfcouncil.orgTampaOtherTEST
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8/4/2017 9:35:44Warren KampeFredkampe5656@gmail. ComInterlachen, Fl. 32148Private Recreational AnglerWould like to see meeting held in Biloxi in October so new council members can be involved .
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8/4/2017 17:16:16Joey Horn
Joeyhorn18@gmail.com
Durant, Fl 33530
Private Recreational Angler
I demand that any final actions be moved to the Biloxi meeting in October because the new council members will not be able to vote at the august meeting and they need to have their say, that is why they were appointed to the council so please let them weigh in!
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8/7/2017 18:11:33Matt Manning
matthmanning@yahoo.com
Valrico, FL 33596
Private Recreational Angler
I demand that any final actions be moved to the Biloxi meeting in October because the new council members will not be able to vote at the august meeting and they need to have their say, that is why they were appointed to the council so please let them weigh in!
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3/30/2018 16:25:02Tom Andersontja4020@gmail.comSt Louis MO. 63144
Private Recreational Angler
It would be nice to manage triggerfish such that it is always possible to catch one or two of them.
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4/17/2018 7:57:12JP Brooker
jbrooker@oceanconservancy.org
FLNGORE: Ocean Conservancy’s Written Comments on Amendment 48-Status Determination Criteria and Optimum Yield for Reef Fish for the Gulf of Mexico Fishery Management Council at the April, 2018 Council Meeting in Gulfport, Mississippi


Dear Ms. Bosarge,


Ocean Conservancy1 is writing to provide comments to the Gulf of Mexico Fishery Management Council (GMFMC, the Council) with a specific focus on delivering to the Council an understanding of the paramount importance of the potential changes to the Status Determination Criteria for Gulf of Mexico reef fish stocks that could take effect through Council action on Amendment 48.2

The changes that the Council makes by way of Amendment 48 could have significant impacts on anglers’ access to fish, including iconic Gulf of Mexico red snapper, and could also dramatically alter the rebuilding progress that has been made so far with key reef fish stocks. Status Determination Criteria are the “nuts and bolts” of the fisheries management machine that when set properly ensure fishermen have the ability to sustainably catch their quotas while also preventing against overfishing.

Ocean Conservancy urges the utmost of precaution when setting Maximum Sustainable Yield (MSY) proxies, Minimum Stock Size Thresholds (MSSTs), Maximum Fishing Mortality Thresholds (MFMTs), and Optimum
Yield ( OY) for the Gulf’s most ecologically and economically reef fish resources, as there is a strong likelihood that missteps in management on these supremely important criteria may negatively alter the fishery for generations.

We would like to note that the actions in Amendment 48 are comparable to the actions in Amendment 44, which focused on MSSTs for specific Gulf reef fish including red snapper. Fundamentally, the changes realized by
way of Amendment 44 weakened sustainable management of important, vulnerable, and economically-valuablefish in the Gulf of Mexico, and ultimately will likely hurt both fish and fishermen in the region. The alternatives selected in Amendment 44 by the Council as preferred shunned the precautionary principle and significantly undermine the considerable rebuilding success that had been heretofore realized for critically important stocks (including red snapper). Amendment 48 runs the risk of the Council and NMFS repeating history by making the same management missteps.

We offer our comments in the two following sections below: first, we offer analysis of the importance and impact of Status Determination Criteria generally, and second we offer specific recommendations on the Actions and Alternatives in Amendment 48.

Status Determination Criteria: The Fisheries Management Diagnostic Toolkit

Status Determination Criteria are a collection of biological markers that reflect the status of a fishery and can indicate if a stock is overfished, undergoing overfishing or is performing adequately. They are the reference points that managers need in order to effectively and legally manage a fishery. These criteria reflect aspects of the fishery that are important for sustainability while also ensuring angler access.

Status Determination Criteria consist of targets (MSY, OY), and thresholds for overfishing (MFMT) and overfished (MSST) levels. The MFMT and MSST levels are connected and are usually set based around the MSY target. See Figure 1 below for an example of how MFMT and MSST are related to MSY and OY.

In situations where MSY reference points cannot be derived, as is the case with Gulf of Mexico reef fish stocks, MSY proxies are often used. A commonly used proxy for fishing mortality (F) that would achieve MSY (Fmsy) is the fishing mortality that would achieve a certain spawning potential ratio (SPR).

SPR is the number of eggs that could be produced by an average recruit in a fished stock divided by the number of eggs that could be produced by an average recruit in an unfished stock. SPR can also be expressed as the spawning stock biomass per recruit (SSBR) of a fished stock divided by the SSBR of the stock before it was fished.

SPR expresses the fraction by which fishing mortality reduces a recruit’s lifetime reproduction output. Often an Fmsy proxy is Fspr% - For example, Fmsy might be set at a rate of 30%SPR, which would be expressed as F30% which is the fishing mortality rate that reduces a recruit’s lifetime reproductive output by 30% relative to an equilibrium state.

Scientists have explored the full range of stock life histories and found that FMSY tend to occur in the range of
F20%SPR and F50% SPR (i.e., the rates of fishing that will keep the SPR within the range of 20-50%).3

SDC consist of management targets and limits that management can react to. An example of how SDC affect an important management output such as an annual catch limit (ACL)
Status Determination Criteria provide fisheries managers multiple controls for management. This means that there are multiple combinations of Status Determination Criteria that can achieve a similar target. An example of this could be when defining Optimum Yield: increasing MSY while decreasing the OY rule will have the same effects as increasing the OY rule and decreasing the MSY.

MSST in particular comes with specific cautions that Ocean Conservancy would like to point out. Amendment 48 notes that MSST needs to be set far enough away from MSY to allow for natural fluctuations in stock biomass, but not so far as to run the risk of recruitment collapse. A precautionary approach would be to set MSST as close to MSY as possible while taking into account natural fluctuations in stock biomass. This gives managers the ability to react quickly with respect to putting rebuilding plans in action. This also has the benefit of generating more consistent and predictable ACLs season after season.

In a scenario where MSST is closer to MSY, if a stock begins to decline a rebuilding plan will be triggered earlier, preventing continued fishing on a stock that would drive further decline. In a scenario where MSST is further from MSY, a stock will be able to continue a declining trajectory for longer, which may ultimately result in more drastic remedial measures, such as large reductions in ACLs, in order to meet rebuilding requirements.

Lowering the SPR proxy typically increases the expected yield over the long term, i.e. equilibrium. However, stocks never follow an equilibrium yield. When recruitment is less than expected, conservative Status Determination Criteria can result in higher and more stable catch. Furthermore, there is the chance that less yield will be lost over the long term if a more precautionary approach to setting Status Determination Criteria is used. When recruitment is lower than expected, or fishing was harder than estimated, conservative reference points leads to both higher yield and biomass. This strategy is especially appropriate for stocks where there is a significant amount of management uncertainty, such as the management uncertainty associated with private recreational red snapper which has seen challenges in restraining catch to the appropriate targets as well as scientific uncertainty associated with red snapper productivity.

Ocean Conservancy has developed a simple model to test and demonstrate the relationships between the various Status Determination Criteria. Using this model, we have produced the example in Figure 3 below:

• A snapper-like stock experience lower than expected recruitment
• Aggressive MSY proxies (SPR 20%; red line) result in fewer landings and less spawning biomass left in the water.
• Conservative proxies (SPR 40%; green line) begin with lower yield but result in much higher yield and almost double the amount of spawning biomass left in the water
• Moderate proxies result in the most stable yield and biomass

Ocean Conservancy wants to underscore for the Council how important Status Determination Criteria are: they are the vital elements that shape all management decisions and are the important levers that Council can use to ensure sustainability and optimize angler access to fisheries resources. We urge the Council to remember that:

1) MSY proxies have an impact on all of the Status Determination Criteria
2) MSST and SPR are the most important Status Determination Criteria and are interrelated
3) Lowering MSST levels and increasing fishing pressure leads to unstable and risky yields
4) If things do not go as expected, for example in a low recruitment scenario, a little precaution in setting Status Determination Criteria goes a long way.

Ocean Conservancy Recommendations for Preferred Alternatives in Amendment 48
We offer the following recommendations and explanations for preferred alternatives in Amendment 48.
Action 1: MSY Proxies Subaction 1.1: Alternative 2, Option 2b – The MSY Proxy for red snapper shall be the yield when fishing at F30%SPR

Subaction 1.2:


Subaction 1.3: Select F40%SPR for Grouper Stocks, F30%SPR for other stocks


Subaction 1.4:


Ocean Conservancy strongly recommends that the Council heeds the advice of its Scientific and Statistical Committee with respect to red snapper MSY proxies – the SSC has recommended that
…the MSY proxy for red snapper be set at the yield corresponding to
F30%SPR. However, it recognizes that F26%SPR is very close to the
recommended level…the SSC has concluded that there is insufficient biological evidence for a better MSY proxy that what is currently used by the Council…for Gulf of Mexico…red snapper4

Fundamentally, lowering the SPR reference point increases the risk. Lower SPR used as MSY proxy allows for a younger stock that is more susceptible to fluctuations in recruitment. Red snapper recruitment is already highly variable and uncertain, so lowering the SPR may only serve to exacerbate this uncertainty from a management perspective. Lowering the SPR is in contravention of the scientific advice given to the Council for years, and Ocean Conservancy recommends that the Council explores selecting a higher SPR.

Furthermore, it is critically important to note that lowering the SPR from its current level will very likely have drastic negative effects on red snapper fishing in the Eastern Gulf. The amendment language points out that:

…over the long-term, fishing at target SPR levels less than 30% will result in declines in the eastern Gulf stock of red snapper, while in the west the SPR will increase at all SPR levels between 20% and
40%.5

All scientific evidence points to an SPR of 30% as a sweet spot for Gulf anglers for red snapper – this will prevent the threat of declines in Florida and Alabama, while fostering increases in the Texas and Louisiana.

On the issue of groupers and other snapper stocks, we recommend that the Council follows the guidance in the Hartford et al paper from 2017 currently in press that urges a 40%SPR for groupers and 30%SPR for other snappers.6
This guidance provides the greatest probability of achieving MSY on a long term basis for these various stocks.

Action 2: Minimum Stock Size Thresholds
Create a new more conservative Alternative 5 that reads as follows:

MSST = (1-M) *BMSY (or proxy) or 0.85*BMSY (or proxy), whichever provides a larger buffer between MSST and BMSY (or proxy).
This alternative accounts for natural fluctuations by including the natural mortality (M) term, providing a modest additional buffer between MSY and MSST for most reef fish stocks, while allowing exceptions for high natural mortality where 0.85 may be too restrictive.

MSST is known as the “overfished threshold.” It is a line drawn at a predetermined, scientifically set amount of biomass. If this line is crossed, critical actions must be taken to ensure the stock remains sustainable and viable for fishermen and communities that depend on it.

Analysis by the Southeast Fishery Science Center (SEFSC) has shown that best practices suggest that default values for stocks with unknown MSSTs should reflect the biology of the individual stocks in the Gulf.7 Further, the SEFSC was clear that alternatives as low as .50*BMSY do not achieve management objectives, and rather that a higher alternative is superior, noting:

In any case, given the current mandate to avoid overfishing, buffers as low as 0.5 BMFMT would appear to have no meaningful effect on the management of moderate to long- lived animals. Based on the results of this work, a buffer of
0.75 BMFMT is recommended for most of the stocks
managed in the Southeast region.8

An alternative such as the one proposed at the top of this section is more appropriate since it provides an increased buffer against natural fluctuations in stock mortality that might otherwise trigger an overfished declaration or a rebuilding plan, even though the probability of such a declaration is already low.

The use of natural mortality is a good proxy to account for a stock’s natural fluctuations in abundance. Long-lived reef fish stocks naturally fluctuate far less than shorter lived species that are prey for a number of species and sensitive to environmental change, such as menhaden. Analysis by both the SEFSC and SSC suggests lowering the MSST proxy for reef fish species is not needed as the stocks analyzed are not expected to naturally fluctuate to an overfished state.9 The SSC, for example, commented that:

…(1-M)*BMFMT appears to be a sufficient buffer against stocksdropping below MSST due to natural fluctuations. However,
lower values of M did result in higher probabilities of the stock dropping below MSST despite not experiencing overfishing.10

Should MSSTs be set at lower levels, such as .50*BMSY, the corrective actions required to recover these stocks would necessarily be more draconian and cause additional—and avoidable—hardship to fishermen. Selecting a higher alternative that takes into account fluctuations in natural mortality gives the greatest prospects of facilitating rebuilding while maintaining access to the fishery.

Action 3: Maximum Fishing Mortality Thresholds
Action 4: Optimum Yield

Both of these actions could use some clarity.

For example, the current MFMT definition sets overfishing limits that are inconsistent with rebuilding, further hampering rebuilding progress through lack of accountability. Alternative 3 under action
2 could address this inconsistency, however further analysis is necessary to determine the actual impacts.

With respect to OY, the annual and long term components are poorly understood and could benefit from more detailed analysis.

Given the interaction between the all of the SDC components, including OY, careful analysis is needed to determine how these actions will impact catch levels for a given set of SDC options relative to the status quo and especially with respect to stocks that are currently in a rebuilding plan such as red snapper and greater amberjack.

Council should request that the SSC examines these actions and consider the development of a decision tool to determine how anglers will be impacted, particularly for rebuilding stocks.

We appreciate the opportunity to share this information with the Council, and please contact me directly if you have any questions or comments.
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