Saving Seafood

Sentient Media Article Omits Major Scientific Debate Over Forage Fish

July 15, 2026 — An article published today by Gaea Cabico in Sentient Media criticizes the use of fishmeal in livestock feeds, including feeds used in raising pigs and chickens, and argues that converting wild-caught fish into animal feed can come at the expense of marine ecosystems.

That is a legitimate subject for examination. But the article’s treatment of forage fish science is incomplete.

To support its argument, the article relies heavily on the 2012 report Little Fish, Big Impact, produced by the Lenfest Forage Fish Task Force and chaired by Ellen Pikitch. It cites the task force’s findings concerning the importance of forage fish to marine predators and repeats its recommendation that forage fish catch rates generally be limited to half the rate associated with maximum sustainable yield.

What the article does not tell readers is that the Lenfest report’s analysis and broad management recommendations later became the subject of a significant peer-reviewed scientific debate.

Prominent Scientists Challenged the Lenfest Conclusions

In 2017, fisheries scientists Ray Hilborn, Ricardo O. Amoroso, Eugenia Bogazzi, Olaf P. Jensen, Ana M. Parma, Cody Szuwalski, and Carl J. Walters published When Does Fishing Forage Species Affect Their Predators? in the journal Fisheries Research.

Their analysis directly questioned whether the Lenfest task force’s generalized conclusions could reliably be applied across different forage species, predator populations, and marine ecosystems.

Among other concerns, Hilborn and his coauthors argued that the Lenfest analysis did not adequately account for:

  • The extreme natural variability of forage fish populations, even in the absence of fishing;
  • The geographic distribution of forage fish and the spatial overlap among predators, prey, and fishing activity;
  • Differences between the sizes of forage fish consumed by predators and those harvested by fisheries;
  • Predators’ ability to switch among prey species; and
  • The distinction between a predator consuming a forage species and the predator population actually being controlled by the abundance of that species.

The authors reported that there was limited evidence of a consistently strong relationship between aggregate forage fish abundance and changes in predator abundance. They concluded that the effects of forage fishing should be evaluated on a case-by-case basis and that broad reductions in harvest rates are not necessarily appropriate for every fishery or ecosystem.

The Lenfest Authors Responded — and the Debate Continued

The Lenfest task force authors responded in the same journal, defending the strength of the connection between forage fish and their predators. Hilborn and his coauthors then published a further rebuttal.

That exchange is important because it shows that the Lenfest report was not the final word on the issue and that its conclusions were not universally accepted.

The scientists on both sides generally agreed that ecosystem effects should be considered in fisheries management. But they disagreed substantially over:

  • The strength and consistency of predator-prey relationships;
  • The adequacy of the models and assumptions used in the Lenfest analysis;
  • The extent to which fishing affects predator populations; and
  • Whether broad precautionary harvest rules should be applied across very different fisheries.

A responsible account of the science should acknowledge that disagreement.

The Article Presents One Side as Settled Science

The Sentient Media article quotes Pikitch, summarizes the Lenfest task force’s findings, and presents its recommended catch-rate reduction without identifying the scientists or research that challenged those conclusions.

That omission creates the impression that the Lenfest recommendations reflect an uncontested scientific consensus. They do not.

This matters because the article makes broad claims about reduction fisheries and the use of fishmeal in livestock production around the world. Forage species, ecosystems, predator dependencies, fishing methods, end uses, and management systems vary considerably.

A small pelagic fishery in one region cannot automatically be assumed to have the same ecological effects as a fishery targeting a different species in another ecosystem. Nor can all species commonly grouped under the label “forage fish” be treated as ecologically interchangeable.

The later peer-reviewed research cautions against exactly that kind of broad generalization.

Fishmeal Policy Should Be Based on Fishery-Specific Evidence

There are valid questions to ask about the sourcing and use of fishmeal, including whether particular fisheries are sustainably managed, whether stocks are healthy, whether ecosystem needs are incorporated into management, and whether fish are being used efficiently.

But those questions should be answered using fishery-specific evidence, not by treating a disputed 2012 report as though it settled the science for every forage fishery in the world.

A meaningful evaluation should examine, at minimum:

  • The status of the individual stock;
  • The fishery’s harvest controls;
  • The natural variability of the population;
  • The species’ role in the local food web;
  • The availability of alternative prey;
  • The spatial relationship between fishing activity and predators; and
  • The actual end uses of the harvested fish.

Some fisheries may warrant greater precaution. Others may already be conservatively managed and operating within ecosystem-based frameworks. Those distinctions are essential.

Readers Deserve the Full Scientific Record

Acknowledging the criticism of the Lenfest report would not require Sentient Media to adopt Hilborn and his coauthors’ conclusions.

It would simply require the publication to tell readers that a major scientific disagreement exists.

A balanced treatment would note that, in 2017, a group of prominent fisheries scientists challenged the generality of the Lenfest task force’s findings. It would also explain that the Lenfest authors disputed that criticism and that the two groups continued the debate in the peer-reviewed literature.

That context is particularly important when an article uses the Lenfest report to support broad policy claims about fishmeal, livestock production, and marine ecosystems.

Readers should be given the complete scientific picture, not one side of a contested debate presented as settled fact.

Relevant Research

Hilborn, Ray, Ricardo O. Amoroso, Eugenia Bogazzi, Olaf P. Jensen, Ana M. Parma, Cody Szuwalski, and Carl J. Walters. “When Does Fishing Forage Species Affect Their Predators?” Fisheries Research 191 (2017): 211–221.

Pikitch, Ellen K., and other members of the Lenfest Forage Fish Task Force. “The Strong Connection Between Forage Fish and Their Predators: A Response to Hilborn et al. (2017).” Fisheries Research.

Ray Hilborn and coauthors. “Response to Pikitch et al.” Fisheries Research 198 (2018): 224.

Pikitch, Ellen K., P. Dee Boersma, Ian L. Boyd, David O. Conover, Philippe Cury, Timothy E. Essington, Selina S. Heppell, Edward D. Houde, Marc Mangel, Daniel Pauly, Éva Plagányi, Keith Sainsbury, and Robert S. Steneck. Little Fish, Big Impact: Managing a Crucial Link in Ocean Food Webs. Washington, D.C.: Lenfest Ocean Program, 2012.

Great Meadows Marsh Project is Restoring Salt Marsh Habitat and Building Resilience in Coastal Connecticut

May 17, 2022 — Funding recovered from three pollution cases is supporting restoration of nearly 40 acres of salt marsh and other coastal habitats at Great Meadows Marsh. The marsh is located in the Stewart B. McKinney National Wildlife Refuge in Stratford, Connecticut. Through this effort, NOAA and partners are strengthening the climate resilience of this important coastal ecosystem.

Great Meadows Marsh lies immediately west of where the Housatonic River meets with Long Island Sound. Most other salt marshes in Connecticut, as well as many marshes along the Atlantic coast, were historically ditched to eliminate disease-carrying mosquitoes. Great Meadows Marsh, however, is home to the largest remaining expanse of unditched salt marsh in Connecticut. The unditched condition of this marsh provides a healthier and more functional habitat overall.

Salt marshes provide habitat for fish and wildlife, trap pollution, and reduce damage from storms and flooding—important benefits  for local communities. The Great Meadows Marsh restoration effort will provide important habitat for fish, including spawning and nursery habitat for forage fish like Atlantic silverside, mummichog, and Atlantic menhaden. It will also help build the ecological resilience of the marsh to respond to increasing sea level rise.

Read the full story at NOAA Fisheries

MSA reauthorization debated in US House of Representatives

November 18, 2021 — Two bills that would reauthorize the Magnuson-Stevens Fishery Conservation and Management Act received a hearing on Tuesday, 16 November, in the U.S. House Natural Resources Subcommittee on Water, Oceans, and Wildlife.

As U.S. Rep. Don Young (R-Alaska) said in a statement, the hearing was “one of contrasts,” as lawmakers reviewed his proposal and one by Subcommittee Chairman Jared Huffman (D-California). Young said Huffman’s bill would take authority away from fishing councils and give it to the U.S. Commerce Secretary. While he agrees with Huffman that some changes should be discussed, Young said the chairman’s bill goes too far.

Read the full story at SeafoodSource

Ahead of Magnuson-Stevens Act Hearing, Studies Question Need for Additional Forage Fish Restrictions

November 16, 2021 — Editor’s note: The following was released ahead of today’s House subcommittee hearing on the Forage Fish Conservation Act. Watch the full hearing here.

 

Today, the House Natural Resources Committee Subcommittee on Water Oceans and Wildlife will hold a hearing on H.R. 5770, the Forage Fish Conservation Act, which would impose new rules on how fisheries managers regulate certain small, schooling, short-lived, pelagic fish and invertebrates that serve as food sources for larger predator species. Two recent studies have raised questions about the need for additional restrictions, and point to existing provisions in the Magnuson-Stevens Act (MSA) that are already ensuring the sustainability of “forage fish” and the species that depend on them.

In addition to the Forage Fish Conservation Act, the subcommittee will consider two bills that would reauthorize and amend the Magnuson-Stevens Act (MSA).  H.R. 4690 is the Democratic Majority’s re-authorization of MSA, sponsored by Subcommittee Chair Jared Huffman (D-California) and H.R. 59, sponsored by Rep. Don Young (R-Alaska).

Proponents of the Forage Fish Act point to the need to keep forage fish populations at extra-precautionary levels, above existing overfishing limits, so that they can better provide for the needs of predator species. But a study released this summer in the journal Conservation Biology, and funded by the Science Center for Marine Fisheries (SCEMFIS), found that, for many predator species, managing forage species at these levels are unlikely to bring additional conservation or environmental benefits. This is especially true in already well-managed and well-monitored fisheries, such as those in the U.S. managed under the existing Magnuson-Stevens Act.

“Management of forage fish populations should be based on data that are specific to that forage fish, and to their predators,” said Dr. Olaf Jensen of the University of Wisconsin-Madison, one of the study’s authors. “When there aren’t sufficient data to conduct a population-specific analysis, it’s reasonable to manage forage fish populations for maximum sustainable yield, as we would other fish populations under the Magnuson-Stevens Act.”

Dr. Jensen and his co-author Dr. Chris Free of the University of California Santa Barbara discuss the results of the paper at greater length in a video released earlier this year. They are joined by scientists Dr. Doug Butterworthof the University of Cape Town, and Dr. Éva Plagányi of CSIRO Oceans and Atmosphere, who offer their independent assessment of the study and their own conclusions on its findings.

To reach these conclusions, the study examined decades worth of abundance data for 45 different predator species and their prey, and found that only 13 percent of them showed any positive impact from having additional, higher levels of forage. Instead, it found that other environmental factors have a far greater influence.

The results of the study reinforce the conclusions of an earlier 2017 study published in Fisheries Research, which found that the fishing of forage fish species had a much smaller impact than previous studies had indicated, and that forage fish were best managed on a case-by-case basis, rather than on broad rules applied across species.

Researchers map best conditions for forage fishes in the Chesapeake

October 28, 2021 — Big fish eat smaller fish, but only if there are smaller fish to eat. A new study led by researchers at William & Mary’s Virginia Institute of Marine Science maps the conditions most suitable for key species of forage fishes in the Chesapeake Bay, offering guidance for any future efforts to protect or restore the habitat required to yield sufficient prey for predatory fishes such as striped bass.

Lead author on the study, which appears in the October issue of Frontiers in Marine Science, is Dr. Mary Fabrizio, a professor and chair of Fisheries Science at VIMS. Co-authors are fellow VIMS researcher Dr. Troy Tuckey, along with Drs. Aaron Bever and Michael MacWilliams of Anchor QEA, LLC. Bever is a VIMS alum.

“Small fishes such as bay anchovy are important components of the diets of predatory fishes in Chesapeake Bay,” says Fabrizio, “but factors that affect local abundances of these  fish have been largely unexplored.”

To throw light on these factors, the research team set out to quantify and map suitable habitats for four common species of forage fishes in Bay waters, and to assess the relationship between habitat extent and fish abundance. In addition to bay anchovy, the forage species studied were juvenile spot, juvenile spotted hake, and juvenile weakfish.

The team based their study on data generated by counting the number of forage fishes caught in a trawl net during fishery surveys conducted by VIMS and the Maryland Department of Natural Resources between 2000 and 2016. These surveys sample at more than 100 sites throughout the Bay each month. They coupled these catch data with output from computer models simulating the environmental conditions at each sampling site. These conditions include water depth and temperature, salinity, stratification, dissolved-oxygen levels, and current speeds. The researchers also noted whether the bay floor beneath each net tow was sandy or muddy, and the distance to the nearest shoreline.

Read the full story at Phys.org

Study finds existing forage fish management is working

July 9, 2021 — Efforts to ratchet down fishing effort on species like herring and menhaden in the name of “extra precautionary management” in most cases are unlikely to bring additional benefits for stocks of predator species that eat them, according to a new study.

“Our results indicate that predator productivity was rarely influenced by the abundance of their forage fish prey,” wrote authors Christopher Free of the University of California-Santa Barbara, Olaf Jensen of the University of Wisconsin-Madison, Ray Hilborn of the University of Washington. “Only 6 predator populations (13 percent of the total) were positively influenced by increasing prey abundance and the model exhibited high power to detect prey influences when they existed,” according to their paper titled “Evaluating impacts of forage fish abundance on marine predators,” originally published in the journal Conservation Biology.

“These results suggest that additional limitation of forage fish harvest to levels well below sustainable yields would rarely result in detectable increases in marine predator populations.”

The findings were released July 6 through the Science Center for Marine Fisheries, a cooperative effort to improve sustainability of fisheries and reduce uncertainty in biomass estimates with work by university partners led with the University of Southern Mississippi Virginia Institute of Marine Science, College of William and Mary, as academic sites.

“Our work suggests that the sustainable limits that we already employ are sufficient for maintaining forage fish abundance above the thresholds that are necessary for their predators,” Free of UC Santa Barbara in a statement describing the findings. “Predators are highly mobile, they have high diet flexibility, and they can go and look for forage fish in places where they’re doing well, switch species for species that are doing well, and have often evolved to breed in places where there’s high and stable forage fish abundance.”

Read the full story at National Fisherman

New Study: Precautionary Catch Limits on Forage Fish Unlikely to Benefit Predators

July 6, 2021 — The following was released by the Science Center for Marine Fisheries:

A newly released study finds that, for many predator species, extra-precautionary management of forage fish is unlikely to bring additional benefits. How to manage forage fish sustainably, both by themselves and for the rest of the ecosystem, has become a much-discussed topic in fisheries management, with regulators of several forage fisheries beginning to adopt precautionary strategies on the premise that they will better provide for the needs of predator species including seabirds, marine mammals, and fish.

The study, from Drs. Chris Free of the University of California-Santa Barbara, Olaf Jensen of the University of Wisconsin-Madison, and Ray Hilborn of the University of Washington, examines decades of historical abundance data of both forage species and their predators, and uses mathematical models to determine to what extent predator populations benefited from increasing abundance of their forage fish prey. Of the 45 predator populations examined, only 6, or 13 percent, were positively influenced by extra forage.

“Our work suggests that the sustainable limits that we already employ are sufficient for maintaining forage fish abundance above the thresholds that are necessary for their predators,” said Dr. Free. “Predators are highly mobile, they have high diet flexibility, and they can go and look for forage fish in places where they’re doing well, switch species for species that are doing well, and have often evolved to breed in places where there’s high and stable forage fish abundance.”

The results have important implications for how strictly to manage forage fisheries. The study finds that, at least in forage fisheries that are already being well managed and are closely monitored, adopting additional precautionary measures will “rarely” provide any additional benefits to predator population growth. However, fishery managers who deal with less well-monitored fisheries may consider more precautionary strategies.

“In places of the world where we already have really strong, very effective fisheries management, additional limitations on forage fish catch are not likely to benefit their predators,” said Dr. Free.

“Management of forage fish populations should be based on data that are specific to that forage fish, and to their predators,” said Dr. Jensen. “When there aren’t sufficient data to conduct a population-specific analysis, it’s reasonable to manage forage fish populations for maximum sustainable yield, as we would other fish populations under the Magnuson-Stevens Act.”

According to the models used in the study, other environmental factors, such as water temperature, are more likely to influence predator populations. These results are consistent with previous efforts to examine the relationship between predator and prey populations.

“What we’ve done here that’s different from previous analyses is try to control for some of the other factors that influence predator population dynamics,” said Dr. Jensen. “In this case, we included in the models a covariate representing ocean temperature.”

SCEMFIS produced a video of the authors and independent experts discussing the results of the paper. Watch it here.

Read the full release here

Impacts of fishing forage fish on the fish that feed on forage fish

June 7, 2021 — Small pelagic fish that school in open water—think sardines or anchovies, are eaten by all kinds of predators. Seabirds, marine mammals, and bigger fish feed on these small pelagics giving them the moniker “forage fish.”

Forage fish support several fisheries, particularly “reduction fisheries,” where fish are caught and reduced into fishmeal and fish oil for livestock and aquaculture. The anchoveta fishery off the coast of South America is the largest in the world, and nearly all catch is reduced. From a food production perspective, reduction fisheries turn fish that humans don’t like to eat into other kinds of meat that humans do. That isn’t to say forage fish aren’t fished for human consumption—they are and have one of the lowest carbon footprints of any food, but the majority of catch is reduced. Eat more anchovies and sardines, people!

However, forage fish also play a foundational role in many ocean ecosystems. They buoy the diets of marine birds and mammals like whales, puffins, albatross, and other vulnerable species while also indirectly supporting valuable fisheries, e.g., salmon and tuna feed on forage fish. Their role in the food chain has led to some calls to limit forage fish fisheries to boost the populations of their higher-value predators. This makes intuitive sense, but new research out this week by Free et al. shows it’s more complicated than simply “more prey, more predators.”

In 2012, a prominent forage fish paper was published that advised a highly precautionary approach to commercial fishing of forage fish. They suggested that to be as conservative as possible, even fisheries currently considered well-managed should be reduced by 50% to enhance and maintain predator populations. It kicked off a decade of forage fish population modeling and scientific discussion. The major criticism of the 2012 paper was that the ecosystem model used in the paper assumed that commercial fishing had an outsized impact on forage fish populations and did not account for ocean conditions. However, forage fish populations are highly sensitive to environmental conditions. For example, long before humans were fishing them, the Pacific Sardine went through periods of significant population boom and bust. This environmental sensitivity complicates the understanding of fishing impact, especially because the predators eat far more forage fish than are taken via fishing. Surly overfishing is bad, but would further reducing fishing below sustainable levels benefit the broader ecosystem?

Scientists did more research. In 2017, a paper by Hilborn et al. showed little correlation between forage fish populations and their predators. The authors argued that if forage fish have natural boom and bust cycles, their predators should have the resilience to find other kinds of prey in times of bust (and indeed, most marine predators that forage on small pelagic fish have a broad diet and are highly mobile). Hilborn et al. challenged the 2012 paper’s recommendations for a highly precautionary approach to forage fish fisheries. However, it was still a relatively simple analysis—the authors used population data to show correlations (or the lack thereof) between the abundance of forage fish and changes in their predator populations. They found that just 5 of the 50 predators examined in that study showed a positive correlation to forage fish population.

The 2017 paper showed correlation but not causality—the paper published this week gets closer to causality by controlling for possible confounding factors, namely by using a predator dynamics model that accounted for forage fish boom and bust cycles. This hadn’t been in previous models. Further, the 2017 paper only looked at U.S. ecosystems; this paper included ecosystems in Europe, South Africa, and the Humboldt Current off South America, giving a more global view of forage fish ecosystem dynamics.

Read the full story at Sustainable Fisheries UW

Bipartisan bill in US Congress aims to better protect forage fish

April 30, 2021 — Two U.S. senators on Thursday, 29 April, filed a bill that calls on the federal government to increase protections for smaller fish that serve as an essential food source for ecosystems across the country.

U.S. Sens. Richard Blumenthal (D-Connecticut) and Roy Blunt (R-Missouri) have filed S.1484, called The Forage Fish Conservation Act. The legislation would amend the Magnuson-Stevens Fishery Conservation and Management Act to mandate that that the U.S. Secretary of Commerce come up with a definition for forage fish as well as take steps to improve monitoring and management for fish that serve as prey to larger fish, birds, and other mammals.

Read the full story at Seafood Source

Surface Slicks are Pelagic Nurseries for Diverse Ocean Fauna

February 5, 2021 — The following was released by NOAA Fisheries:

To survive the open ocean, freshly hatched tiny fish larvae must find food, avoid predators, and navigate ocean currents. Their experiences during these great ocean odysseys have long been a mystery, until now. We have discovered that a surprisingly dense and diverse array of marine animals find refuge in so-called “surface slicks” during early life. To view an immersive, interactive version of this story, check out our story map: Hidden World Just Below the Surface.

Surface slicks are home to the larvae of at least 112 marine fish species, including commercially and ecologically important fish such as mahi-mahi, jacks, and billfish. Serving as makeshift nursery habitats, surface slicks are meandering lines of smooth surface water that collect plankton and shelter-providing debris. They are formed from the convergence of ocean currents, tides, and variations in the seafloor.

“These ‘bioslicks’ form an interconnected superhighway of rich nursery habitat that accumulate and attract thousands of young fish, along with dense concentrations of food and shelter,” says Dr. Jonathan Whitney, a research marine ecologist for NOAA and lead author of the study, published today in Scientific Reports. “The fact that surface slicks host such a large proportion of larvae, along with the resources they need to survive, tells us they are critical for the replenishment of adult fish populations.”

That  larvae hosted in slick nurseries grow up and radiate out into neighboring ecosystems. There, they join adult fish populations from shallow coral reefs to the open ocean to the bottom of the deep sea.

What’s more, many forage (prey) fish, like flying fish, spend their larval and juvenile life stages in surface slicks. “These biological hotspots provide more food at the base of the food chain that amplifies energy up to top predators,” says study co-author Dr. Jamison Gove, a research oceanographer for NOAA. “This ultimately enhances fisheries and ecosystem productivity.”

Read the full release here