October 24, 2017 Megan Ware Atlantic States Marine Fisheries Commission 1050 North Highland Street, Suite 200A-N Arlington, Virginia 22201 [sent via email] Dear Ms. Ware and Menhaden Management Board members, On behalf of The Nature Conservancy, I am writing to offer comments on our preferred management options in draft Amendment 3 to the Atlantic Menhaden Fishery Management Plan. We commend the Atlantic States Marine Fisheries Commission staff and Plan Development Team members for developing the suite of options contained in this comprehensive Amendment. The Nature Conservancy has chapters in all 15 states represented on the Menhaden Management Board, and our marine conservation work prioritizes sustainable seafood, strong coastal communities and a healthy ocean. We are committed to helping create and maintain the conditions necessary for healthy and resilient marine and estuarine food webs which benefit nature and people. On the Atlantic coast, long-term success in this effort requires ensuring that forage fishes, including Atlantic menhaden, remain abundant and available as forage, at all life stages, throughout their historic ranges. We encourage the Commission to make three important changes to menhaden management through this Amendment: 1) Implement interim Ecological Reference Points now. 2) Adjust coast-wide Total Allowable Catch allocations to better reflect the current distribution and abundance of menhaden from Maine to Florida. 3) Maintain the Chesapeake Bay Reduction Fishery Cap and set it at the average of the last 5 years catch (Option B). Reference Points: The menhaden population has expanded in recent years--we are seeing more, bigger fish in the northern part of their range, which we attribute, in part, to the catch limits implemented in 2012. To build on this success, it is important to now codify the Commission s intent to define those limits using Ecological Reference Points (ERPs) which account for menhaden s important role as prey for a wide range of predators. Single-species reference points are not appropriate for menhaden because they do not adequately account for the critical role of menhaden as forage in the ecosystem. We recognize that the ASMFC s Biological and Ecological Reference Point Working Group (BERP WG) is working on sophisticated multi-species models for estimating menhaden-specific ERPs, and we support the continuation of that work. However, these models won t provide useable reference points until at least 2019, with additional time needed for ASMFC process and implementation. The Amendment 3 process gives us an opportunity to begin the shift toward a scientifically-supported, ecosystemapproach to management, and we think it is important to take this step now. 1
With regard to the options laid out in Draft Amendment 3, our advice is a bit more complicated. The Draft identifies three potential interim ERPs to use until the BERP WG finishes its work. In principle, the Conservancy supports using a two-tiered system with management targets, overfishing thresholds, and control rules. For this reason, we initially supported Option E, a 75% unfished biomass target and 40% unfished biomass threshold, during public hearings and in communications with partners. However, we were simultaneously seeking clarification of methods used to calculate unusually high fishing mortality rates associated with Option E (F40% =1.493). Our informal inquiries eventually led to our submitting a memo to the BERP WG, which we attach as Appendix A to this letter. The memo expresses our concern that the use of total biomass for calculating F40% is problematic because of the high proportion of immature fish in the population (> 50%) and the currently estimated fishery selectivity curve. These factors would lead to an almost total loss of mature adults if the Management Board decided to manage anywhere near the proposed threshold fishing mortality rate of 1.49 (biomass-weighted value). Following consultation between our scientists and other academic and government scientists, we offered a solution based on standard practice in fisheries science. It is unfortunate that we were not able to provide this advice prior to the end of the public scoping period due to our lack of information on how the BERP WG would interpret existing scientific guidance on forage fish management and the methodology it would use. The overfishing threshold, as currently calculated in Option E (using total biomass instead of the more standard spawning stock biomass) is very concerning because it could allow extremely high fishing mortality rates. Such rates could lead to the collapse of the stock, which would of course be contrary to all the stated goals of management. The BERP WG has repeatedly noted that the level of fishing pressure that reduces total biomass to 40%B 0 [in Option E] is higher than almost anything seen in the history of the fishery and results in almost total loss of spawning adults (Memo M17-74, July 14, 2017). The Conservancy s initial support for Option E was based on the assumption that the target and threshold reference points would reflect the spirit and intent of adopting Ecological Reference Points that maintain high abundance for all year classes of menhaden. If the 40% overfishing threshold were recalculated to maintain 40% of the spawning population, then the threshold reference point would offer sufficient protection for the stock. Unless the dangerous threshold limit in Option E is rectified, the Conservancy will have to support Option D going forward. We believe that establishing an ERP based on a target of 75% of total unfished biomass could meet goals for sustaining fisheries and menhaden predators. However, since Option D does not include an explicit overfishing threshold, it will be critically important for the Commission to establish harvest control rules based on that target. Quota Allocation: Quota allocation should reflect management goals for an expanded menhaden distribution that supports diverse fish and wildlife species and associated businesses along the entire Atlantic coast. Reallocation will help states that are currently struggling to manage existing bait fisheries within their current allocation limits. Quota allocation needs to account for range expansion as the population rebuilds, but should not encourage development of new large-volume fisheries. If the Board decides to maintain a state-bystate allocation, then adopting a minimum state allocation of 1-2% for states that desire it (with quota transfer provisions) would simplify the administration and management of the fishery by eliminating 2
the need for most of the accounting and set aside provisions. Regardless of which allocation scenario and transfer provisions the Commission selects, all menhaden landings need to be documented and counted as part of the Total Allowable Catch. Chesapeake Bay Reduction Fishery Cap: Chesapeake Bay is the most productive nursery area for Atlantic menhaden, and the Chesapeake Bay Reduction Fishery Cap is an important management tool to increase the survival of younger fish in the Bay. Ideally the cap would be established using ecosystembased management principles, but the current cap of 87,216 metric tons was not. Therefore, the Management Board should re-evaluate it and adjust as needed to ensure ecological relevance. Until the Technical Committee can provide science-based advice on an ecologically relevant cap for the Bay, the current cap should be adjusted to more closely align with recent landings. We support Option B as the best way to achieve this goal. This interim adjustment will maintain the existing Chesapeake Bay fishery at current levels during the reevaluation period. Thank you for considering our comments. Please contact Kate Wilke at kate.wilke@tnc.org or (804) 249-3412 with any questions or ideas for how we might assist. Sincerely, Jay Odell North America Fisheries Director The Nature Conservancy 3
Appendix A MEMORANDUM September 21, 2017 TO: FR: Biological and Ecological Reference Point Working Group Jason McNamee, Chair, Atlantic Menhaden Technical Committee Bob Ballou, Chair, Atlantic Menhaden Management Board Kate Wilke, Mid-Atlantic Marine Program Director, The Nature Conservancy Dr. Rich Bell, Fishery Scientist, The Nature Conservancy Dr. Jerald S. Ault, University of Miami SJ: Calculation of 75% target with 40% threshold (ERP Option E) We greatly appreciate the BERP Working Group s focused efforts to generate the suite of ERP options that were presented in Draft Amendment 3 based on the best available science for forage species. After our review of Draft Amendment 3; the BERP Working Group s memo M17-74 of July 14, 2017, that explains these calculations; and, Dr. Katie Drew s August 2 nd presentation, we have some with concerns with the way these calculations were performed and their potential impacts on the Atlantic menhaden stock. Smith el at. (2011 1 ), Pikitch et al. (2012 2 ) and references within recommended a target of 75% of unfished biomass to decrease impacts on predators to balance and enhance sustainability of marine ecosystems. Both studies recommended that specific biomass thresholds be combined with the 75% target to help achieve ecological objectives while ensuring ongoing fishery yields. Pikitch et al. (2012) specified a threshold value of 40% unfished biomass for intermediate information tier species. As we understand it, the BERP WG calculated the 75% target and 40% threshold using a biomass-perrecruit model with total biomass as opposed to spawning stock biomass. Currently, the majority of the menhaden biomass (>50%) is comprised of ages 0 and 1 fish. Because it was assumed that the gear primarily selects for ages 2-4, even under extraordinarily high fishing mortality rates it would be nearly impossible to fish the stock down to 40% of unfished total biomass (B0). We feel that these particular analyses do not specifically account for spawning biomass and thus would subject reproductive-age fish to dangerously high fishing mortality rates. Such high fishing mortality rates would compromise the sustainability of the stock and long-term yields. The reported rates at the threshold reference point are strictly untenable. Fishing at these levels would result in severe truncation of stock size/age structure, 1 Smith, A. D. M., et al. 2011. Impacts of fishing low trophic level species on marine ecosystems. Science, 333(6046), 1147 1150. 2 Pikitch, E., et al. 2012. Little Fish, Big Impact: Managing a Crucial Link in Ocean Food Webs. Lenfest Ocean Program. Washington, DC. 108 pp.
geographic range, and reproductive potential. This would be counter to the ASMFC s stated menhaden management goals. While we respect that these calculations were done in accordance with an interpretation of the best available science for management of forage species, we believe that we should also tailor this advice using the best scientific knowledge of Atlantic menhaden biology and the fishery. We know that Atlantic menhaden live longer than other forage species, and they don t reach sexual maturity until 2yrs or older. In addition, a dome-shaped selectivity curve is used to describe the impact of fishing mortality on stock age/size structure. Based on these characteristics, calculating the ecological reference points in terms of total biomass, without regard for the spawning biomass, leads to perverse conclusions about acceptable levels of fishing mortality. Our findings concur with the BERP WG s own findings (i.e., August 2017 BERP presentation to the Board 3 ), clearly stating that Reference points that focus on conserving total biomass may result in a level of spawning potential well below the FEC limit. Therefore, we suggest using biomass-per-recruit calculations focused on spawning stock biomass or fecundity (spawners- or fecundity-per-recruit), as has been consistently reported in previous menhaden assessments and forms the basis for the current standard single species reference points in national and international fisheries management commissions and councils. The use of spawners- or fecundity-perrecruit will avoid the unintended potential consequence of excessive fishing pressure on mature fish. We further request that the methodology for computing the biomass-weighted F be clearly displayed in a draft Amendment table as well. 3 Atlantic Menhaden Stock Assessment Update, August 2017, Alexandria, VA, p. 67.