May 20, 2016 — The following is an op-ed by Dave Frulla and Anne Hawkins, published in the June 2016 issue of National Fisherman:
In 2012, the Lenfest Ocean Program commissioned a report entitled “Little Fish, Big Impact,” regarding management of lower trophic level fisheries. Lenfest and other environmental groups followed the report’s publication with a major domestic and international media campaign. If Lenfest wanted to spark scientific debate and inquiry regarding forage fish management, it did a good job. If, however, its plan was to drive a “one- size-fits-all” solution to a complex problem, the results are far less constructive.
The report consisted of a literature review and basic computer modeling to “quantify” the value of forage fish to their predators. It concluded these fish were twice as valuable to other animals as for human nutritional, agricultural and aquaculture uses. The report thus recommended cutting forage fish catch rates between 50 and 80 percent across the board, to double the amount of forage fish left for fish, seabirds and other predators. It also recommended closures for spawning and around seabirds that rely on forage fish, and instructed no additional forage fish fisheries be authorized.
At release, the Lenfest report was received relatively uncritically, despite its far-reaching conclusions and recommendations. Since then, globally preeminent fishery scientists, including some of the Lenfest report’s own authors, have begun to examine the report’s assumptions and conclusions. Despite the report’s confident tone, there is no consensus on whether special management measures will provide any benefit to forage stocks.
Criticism of the Lenfest report can be divided into two main categories: its application to specific forage species, and its general methodology. Regarding application to specific species, it is important first to highlight there is no common definition of “forage fish.” It is, rather, a loosely formed concept, given how many marine organisms (and not just finfish) can be labeled important prey species for a given ecosystem or even for just one species.
Further, not all low trophic species fit the Lenfest report’s biological archetype. For instance, in April 2015, the Atlantic States Marine Fisheries Commission’s Biological Ecological Reference Points Workgroup presented a Memorandum to the Commission’s Menhaden Management Board stating that, “Ultimately, the BERP WG does not feel that the management actions recommended in [the Lenfest report]… are appropriate for Atlantic menhaden specific management,” in part because menhaden do not exhibit the stock-recruit relationship assumed in the Lenfest paradigm. (That is, menhaden recruitment is driven by environmental factors, rather than spawning stock size.)
As to methodology, the Lenfest report largely drew conclusions from ecosystem models that were not designed to evaluate management strategy impacts on low trophic level fisheries. The Lenfest report admits this shortcoming. Indeed, after its publication, Lenfest report authors Tim Essington and Eva Plaganyi co-authored their own follow-up paper showing that among the most common features absent from most of these ecosystem models were natural variability of forage fish stocks, important aspects of spatial structure, and the extent of overlap in size of predator and prey stocks. Regarding the last factor, a predator may eat smaller-sized year classes of prey fish than a fishery targets. Accordingly, humans and the predator fish aren’t competing; the forage species ran the predation gauntlet before being subject to fishing. Overall, Essington and Plaganyi concluded that “most of [the existing] models were not developed to specifically address questions about forage fish fisheries and the evaluation of fishing management.” Model suitability is but one element of the post-Lenfest report work on the scientific agenda for further consideration.
The ultimate question is whether the public, press and fisheries managers will pay attention as fisheries scientists pursue the important questions the Lenfest report raised, but did not resolve. The situation is reminiscent of the debate that occurred following publication by Dr. Boris Worm and other scientists of a 2006 report in Science suggesting all fisheries could collapse by 2048. That report received the same sort of PR roll-out as the Lenfest forage fish report. (We understand Dr. Worm’s work also received Pew Charitable Trusts/Lenfest funding.)
In 2009, Drs. Worm, Ray Hilborn (not a co-author of the initial report), and 19 other scientists collaborated on a subsequent report in Science concluding that existing fishery management tools were reversing the claimed global trend of depletion for individual stocks, and the situation was not so dire as Dr. Worm originally forecast. To this day, though, Dr. Worm’s original report is presented in press and policy debates without mention of his even more significant subsequent collaborative work. We hope the Lenfest report on forage fish management represents one early element — but not the final word — in consideration of the important topic it addresses.