Saving Seafood

What factors play a role in analyzing forage fish fishing regulation?

July 7, 2017 — The interaction of predators, fishing and forage fish is more complicated than previously thought and that several factors must be considered, says researcher.

The group of researchers was evaluating the interaction after results from an earlier report found that fishing of forage species had a large effect on predator population, said the Marine Ingredients Organization (IFFO). Those harvested fish are used in several areas including as feed ingredients.

The new study was initiated because there were some questions regarding the methods used in the initial project, said Ray Hilborn, with the school of aquatic and fishery sciences at the University of Washington and corresponding author.

“When the original Lenfest [Forage Fish Task Force] report came out, a few of us said it seemed that the methods they were using were not up to the questions they were asking,” he told FeedNavigator. The report also offered several policy recommendations, he added.

“It was on our radar screen,” he said. “And one of the things I’ve been interested in looking at is the intensity of natural fluctuation in populations, and forage fish are notable for how much they vary naturally.”

The interaction between forage fish populations and predators is more complicated than may have been suggested by earlier studies tracking that relationship, and several factors need to be considered when analyzing the role that fishing plays on that relationship, he said. “The key point isn’t that there isn’t an impact, but that you have to argue case-by-case,” he added.

Several factors need to be considered when assessing the interaction among predators, forage species, and fishing of those forage species, the researchers said in their study. “We show that taking account of these factors generally tends to make the impact of fishing forage fish on their predators less than estimated from trophic models,” they added.

Read the full story at Feed Navigator

EU Discard Ban Stimulates Innovation and Improved Cross-Sectoral Communication

July 7, 2017 — The following is a report written by Dr. Bill Karp, Affiliate Professor at University of Washington:

The Common Fisheries Policy (CFP) governs fisheries management in the European Union and is, very roughly equivalent to the Magnuson-Stevens Act in the US. The CFP is updated (reformed) every ten years. Article 15 of the 2013 reform is entitled “Landing Obligation” and includes the following text:

  1. All catches of species which are subject to catch limits and, in the Mediterranean, also catches of species which are subject to minimum sizes as defined in Annex III to Regulation (EC) No 1967/2006, caught during fishing activities in Union waters or by Union fishing vessels outside Union waters in waters not subject to third countries’ sovereignty or jurisdiction, in the fisheries and geographical areas listed below shall be brought and retained on board the fishing vessels, recorded, landed and counted against the quotas where applicable, except when used as live bait, in accordance with the following time-frames:

For further details (including exceptions) see http://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:32013R1380&rid=1

This “Landing Obligation” or discard ban was enacted in response to public concerns regarding perceived wasteful practices. It is being implemented over several years, initially in the more industrialized, large scale fisheries of northern Europe. Many concerns about practicability, cost, and other aspects have been raised and hotly debated in Europe, but implementation is proceeding.

As expected, this change in public policy has directly impacted many aspects of fishing, handling, processing, and marketing. The EU has funded several projects designed to encourage cross-sectoral engagement to improve gear selectivity, share information on avoiding unwanted catch (spatial, areal, etc.), encourage advances in handling, stimulate marketing opportunities, etc. Among these initiatives is a project called “DiscardLess” which is a four-year, multi-million Euro project. Through this project, researchers and stakeholders from throughout Europe and elsewhere are working together to reduce discards in European fisheries. The DiscardLess Consortium includes 31 partners from 20 countries.

Participants include fishermen, gear technologists, economists, handling, processing and marketing experts, and marine scientists. Work packages within the project focus on selectivity, avoidance, optimal use, ecosystem considerations, and policy aspects. Work began more than two years ago, and some important results are already apparent. For example, the Atlas, and Selectivity Manual provide broad-based and comprehensive information, much of which will be useful to US fishermen. See http://www.discardless.eu/ to download these products and learn more about the DiscardLess project. For an excellent short video about DiscardLess, see https://player.vimeo.com/video/206395350

FRI trains the fishery managers of tomorrow

June 26, 2017 — Area management biologists in Bristol Bay are responsible for tracking and maintaining the escapement numbers of multiple salmon species in multiple river systems. Not only are they charged with preserving the health of the run’s biology, but they are often held, at least partly, accountable for the economic viability of the fishery as well. One of the inherent challenges of the job is that the sustainability of the salmon run is not always synonymous with the profit margins of industry entities, and the managers are often the first to be blamed when the catch and escapement don’t go as planned.

The University of Washington’s Fisheries Research Institute is taking on the tall task of training those who hope to one day be fishery managers. Seven grad students—two from the University of Alaska Fairbanks, three from the University of Washington and two from Kamchatka State Technical Institute in Russia—are taking the three week course at FRI’s cabin on Aleknagik Lake.

Professors Milo Adkinson and Ray Hilborn are teaching the course.  “We bring our graduate students in fisheries out to see a real fishery in action,” said Adkinson.

For the class’s main term project, the students will work directly with the three area management biologists in Bristol Bay as the salmon run is going on.

“They get to pretend that they’re managing the fisheries,” said Adkinson. “So I’ve got a group of students that are going be deciding whether to open and close the Naknek-Kvichak district every day.”

The students will simulate making announcements relevant to the current salmon run, allocating when and where sport and commercial fisherman are allowed to fish. They will then be given a math equation which will determine the catch and escapement numbers based on the management decisions they made. The students will receive feedback from the actual area managers as the course progresses.

“We had one year where the students let several million fish escape into the Egegik system. I think the managers got a kick out of that,” said Adkinson.

Tim Sands is the area management biologist for the Nushagak and Togiak districts. He gave a lecture at FRI this week, and is making himself available to answer any questions the students charged with simulating his job might have.

“So there’s rules like what time of the tide you have to open the set nets—it’s all specified in the management plan. They can ask me questions like that, or things about allocation,” said Sands. “That’s what I do. Tell them the rules of the district.”

Read the full story at KDLG

Ray Hilborn: World fish stocks stable

June 12, 2017 — Speaking at the SeaWeb Seafood Summit on Wednesday, 7 June in Seattle, Washington, U.S.A., University of Washington fisheries researcher Ray Hilborn said the perception that the world’s fish stocks are declining is incorrect, and that fishing could sustainably be stepped up in areas with good management.

Hilborn pointed to figures from the RAM Legacy Stock Assessment Database that indicate that fish stocks dipped through the last part of the 20th century, but have since recovered in many fisheries.

“There is a very broad perception that fish stocks around the world are declining. Many news coverages in the media will always begin with ‘fish stocks in the world are declining.’ And this simply isn’t true. They are increasing in many places and in fact, globally, the best assessments are that fish stocks are actually stable and probably increasing on average now,” Hilborn said.

The RAM Legacy Database collects information on all the stocks in the world that have been scientifically assessed, which is a little more than half of the world’s catch.

“What we don’t really know about is the big fisheries in Asia, in the sense that we don’t have scientific assessments of the trends in abundance,” Hilborn said.

He added that the general consensus is that the status of those stocks is poor, a result of, among other things, poor fisheries management, reinforcing surveys that have shown a direct correlation between high stock abundance and high intensity of management.

“For most of the developed world fisheries’ management is quite intense, and South and Southeast Asia stand out as really not having much in the way of fisheries’ management systems, particularly any form a enforcement of regulations, if regulations exists,” he said.

But in much of the developed world, Hilborn said fish stocks are robust, even when they sometimes get labeled as overfished.

Read the full story at Seafood Source

CFOOD: New Study Sheds Light on Relationship Between Forage Fish, Predators, and Fishing

April 18, 2017 — The following was published by CFOOD. Founded by Dr. Ray Hilborn from the University of Washington, CFOOD is a network of scientists formed to study the science of fisheries sustainability, and to correct erroneous stories about fisheries in the mainstream media:

A paper published earlier this month shows a new understanding of how commercially fishing forage fish impacts forage fish predators like sea birds, marine mammals, and pelagic finfish.

Forage fish are small, silvery, bottom-of-the-food-chain fish that eat plankton and small invertebrates. They are eaten by seemingly everything in the ocean, providing “forage” for many other animals—you’ve probably heard of the two most common forage fish: sardines and anchovies. If asked their favorite marine species, not many people would choose a forage fish, but many would choose a forage fish predator: Penguins and puffins are endearing, dolphins and seals are adorable, and tuna and swordfish are delicious. Forage fish help sustain these populations, but are also favorite foods for many cultures.

With a high oil and protein content, forage fish are also the perfect species for conversion to fishmeal and fish oil. The largest fishery in the world, Peruvian anchovy, is such a fishery. Fish oil provides essential fatty acids and is sold in drugstores as a nutritional supplement. Fishmeal is food for several of our favorite edible animals. It is especially important in farmed fish production (like most of the salmon eaten in the US), but is also fed to terrestrial livestock like cows and pigs. Essentially, forage fish fisheries take a renewable resource and turn them into protein that people eat.

But how do these fisheries affect the marine predators that feed on forage fish? This is an important question that has only recently been investigated. A paper published in 2012 used mathematical models to estimate the impact of fishing forage fish populations on their predators and recommended that commercial reduction fishing be cut by 50-80% to ensure forage fish predators get enough food. However since then, several papers—including some by the authors of the original—have recognized that the models used in the 2012 research were not suitable for the questions asked, and further studies are needed.

The latest, Hilborn et al. (2017) published earlier this month (open access), shows that environmental variability, left out of the original models, is actually the most important factor affecting forage fish populations. Commercial fishing often has little effect on forage fish populations and their predators. Instead, ocean conditions and nutrient cycles (things humans have no control over) dictate how many forage fish survive each year.

The new paper also suggests that the relationship between forage fish and their predators is complicated by several factors. Forage fish predators often rely on specific, high-density locations where the abundance may be largely unrelated to the total abundance of the population. Basically, instead of predators relying on the total number of forage fish, they rely on forage fish appearing in certain locations, such as near breeding areas. Predators are also not singularly reliant on commercially harvested forage fish to survive—most consume a wide variety of prey. Indeed, Hilborn et al. (2017) found no link between larger forage fish populations and increases in predator populations.

Forage fish provide a wonderful service to humans. They are tasty, nutritious, and their harvest provides food for animals that we enjoy and eat, both above and below the surface. Understanding their ecological role is important to ensure sustainability.

Read the story at CFOOD

Watch a video about the study here

Read an infographic about the study here

D.B. Pleschner: Study: No correlation between forage fish, predator populations

April 10, 2017 — On April 9-10, the Pacific Fishery Management Council is meeting in Sacramento to deliberate on anchovy management and decide on 2017 harvest limits for sardine, two prominent west coast forage fish.

Extreme environmental groups like Oceana and Pew have plastered social media with allegations that the anchovy population has crashed, sardines are being overfished and fisheries should be curtailed, despite ample evidence to the contrary.

Beyond multiple lines of recent evidence that both sardines and anchovy populations are increasing in the ocean, a new study published this week in the journal Fisheries Research finds that the abundance of these and other forage fish species is driven primarily by environmental cycles with little impact from fishing, and well-managed fisheries have a negligible impact on predators — such as larger fish, sea lions and seabirds.

This finding flies directly in the face of previous assumptions prominent in a 2012 study commissioned by the Lenfest Ocean Program, funded by the Pew Charitable Trusts, heirs of Sun Oil Company. The Lenfest study concluded that forage fish are twice as valuable when left in the water to be eaten by predators and recommended slashing forage fishery catch rates by 50 to 80 percent.

However, in the new study, a team of seven internationally respected fisheries scientists, led by Prof. Ray Hilborn, Ph.D., of the University of Washington, discovered no correlation between predator populations and forage fish abundance. The new research also found multiple omissions in the methodology of the Lenfest study. For instance, it — and other previous studies — used ecosystem models that ignored the natural variability of forage fish, which often fluctuate greatly in abundance from year-to-year.

Read the full opinion piece at the Santa Cruz Sentinel

When is menhaden like a mortgage?

April 7, 2017 — What do forage fish and real estate have in common? Location, location, location.

A new study led by University of Washington fishery science Professor Ray Hilborn reveals some surprising relationships between predator success and prey abundance.

The paper, “When does fishing forage species affect their predators?” was published Monday in the journal Fisheries Research in response to the 2012 Lenfest Report, which set the recent standard for forage fish management by asserting that an across-the-board reduction in the commercial harvest of forage fish would result in higher numbers of fish species that prey on them.

“It looked reasonable that if you appropriate half of the production of a prey species by a fishery that you can’t support so much production of predators,” said Carl Walters, professor emeritus of the University of British Columbia’s Institute for the Oceans and Fisheries. “That seemed perfectly reasonable. It was just wrong.”

According to this study, prey species follow the real estate principle of investing in prime locations. When forage fish are abundant, the research shows, their population spreads over a wider area, creating smaller subpockets around a core reproduction zone. When they’re in low abundance, they retract to the core region. Successful predators keep their breeding grounds close to that core region, maintaining access to food even in times of low prey biomass.

Read the full story at National Fisherman

New Study Challenges Earlier Findings Regarding Link Between Predators, Forage Fish

WASHINGTON (Saving Seafood) – April 3, 2017 – A new study published today in Fisheries Research finds that fishing forage fish may have a smaller impact on their predators than previously thought. The study, authored by a team of marine scientists led by renowned University of Washington fisheries expert Dr. Ray Hilborn, calls into question previous forage fish research that may have overestimated the effect of fishing of forage fish on their predators.

The study, “When does fishing forage species affect their predators?,” finds that changes in predator populations are largely unrelated to the abundance of forage fish. It also shows that the distribution of forage fish is more important to predators than their overall abundance, and that many predators prefer smaller forage fish that are largely unaffected by fishing. Based on these results, the authors recommend that forage fishing policies be created on a case-by-case basis.

The paper’s findings point to issues with previous forage fish research, most notably a five-year-old study funded by the Lenfest Ocean Program, managed by The Pew Charitable Trusts, which it says failed to consider important variables like the spatial distribution of forage fish. Arguably the largest oversight in past research was the high natural variability of forage fish populations, even in the absence of fishing, the authors write.

“There is little evidence for a strong connection between forage fish abundance and the rate of change in the abundance of predators,” the authors write. “The fact that few of the predator populations evaluated in this study have been decreasing under existing fishing policies suggests that current harvest strategies do not threaten the predators and there is no pressing need for more conservative management of forage fish.”

The authors suggest that the lack of a strong relationship between forage fish and their predators is the result of “diet flexibility” – the idea that predators can switch between prey species, helping them defend against the high natural variability of forage fish populations.

This finding contradicts the widely reported conclusions of the Lenfest Forage Fish Task Force in 2012. The study, “Little Fish, Big Impact,” claimed that forage fish are twice as valuable to humans when they are left in the water, rather than fished, because of their great importance to predator species. Based on this conclusion, the Lenfest group recommended cutting forage fish catch rates across the board by 50 to 80 percent.

But Dr. Hilborn and his coauthors advocate for a more nuanced approach, writing that previous models “were frequently inadequate for estimating impact of fishing forage species on their predators” and that “a case by case analysis is needed.” The team explicitly calls into question the Lenfest study’s recommendations, which it says are “not appropriate for all species.”

“Relevant factors are missing from the analysis contained in [the Lenfest] work, and this warrants re-examination of the validity and generality of their conclusions,” the authors write. “We have illustrated how consideration of several factors which they did not consider would weaken the links between impacts of fishing forage fish on the predator populations.”

These missing elements include how fishing mortality compares with the natural variability of forage species, the spatial structure of forage fish populations, and the overlap between the sizes of forage fish eaten by predators and size taken by the fishery.

“It must be remembered that small pelagic fish stocks are a highly important part of the human food supply, providing not only calories and protein, but micronutrients, both through direct human consumption and the use of small pelagics as food in aquaculture,” the paper concludes. “Some of the largest potential increases in capture fisheries production would be possible by fishing low trophic levels much harder than currently.”

Read an infographic about the study here 

Watch a video about the study here 

Hilborn-led study: Predators less affected by catch of prey fish than thought

April 3, 2017 — Stocks of predatory fish may be less affected by the catching of their prey species than has previously been thought, according to new research published on April 3.

The study – published in journal Fisheries Research and led by well-known University of Washington professor Ray Hilborn – suggests previous studies on this topic overlooked key factors when recommending lower catches of “forage fish”.

Said forage fish include small pelagic species, such as anchovies, herring and menhaden.

The team of seven fisheries scientists found that predator populations are less dependent on specific forage fish species than assumed in previous studies, most prominently in a 2012 study commissioned by the Lenfest Ocean Program, which is managed by the Pew Charitable Trusts.

The Lenfest Forage Fish Task Force at that time argued that forage fish are twice as valuable when left in the water to be eaten by predators, and recommended slashing forage fish catch rates by up to 80%.

For fisheries management, such a precautionary approach would have a large impact on the productivity of forage fisheries. As groups such as IFFO (the Marine Ingredients Organisation) have noted, these stocks contribute strongly to global food security, as well as local and regional social and economic sustainability.

Read the full story at Undercurrent News

Hilborn Study Redefines Forage Fish Predator Relationships; Suggests Fishing Pressure Lesser Factor

April 3, 2017 — SEAFOOD NEWS — New research published today in the journal Fisheries Research finds that fishing of forage species likely has a lower impact on predators than previously thought, challenging previous studies that argued forage fish are more valuable left in the ocean.

In 2012 a Lenfest study got wide play claiming that models showed fishing pressure on prey species had big impacts on the abundance of predator species, such as cod and tuna.  However, some of the authors of the original model have now joined with other researchers to say it is out of date.

A team of seven respected fisheries scientists, led by Prof. Ray Hilborn, Ph. D., of the University of Washington, found that predator populations are less dependent on specific forage fish species than assumed in previous studies including a 2012 study commissioned by the Lenfest Ocean Program is managed by The Pew Charitable Trusts. The Lenfest Forage Fish Task Force argued that forage fish are twice as valuable when left in the water to be eaten by predators, and recommended slashing forage fish catch rates by 50 to 80 percent.

For fisheries management, such a precautionary approach would have a large impact on the productivity of forage fisheries. As groups such as IFFO (The Marine Ingredients Organisation) have noted, these stocks contribute strongly to global food security, as well as local and regional social and economic sustainability.

However, the new research found multiple omissions in the methodology of the Lenfest study. “When you review the actual models that were used [by Lenfest], there are a few key elements on the biology of these animals that were not represented, ” said Dr. Ricardo Amoroso, one of the study’s co-authors. He added that one of the authors’ approaches was to “look for empirical evidence of what is actually happening in the field. ” Previous studies relied on models which took for granted that there should be a strong link between predators and prey.

Specifically, the Lenfest study and another study using ecosystem models ignored the natural variability of forage fish, which often fluctuate greatly in abundance from year to year. It also failed to account for the fact that predators tend to eat smaller forage fish that are largely untouched by fishermen. Because of these oversights, the new study concluded that the Lenfest recommendations were overly broad, and that fisheries managers should consider forage species on a case-by-case basis to ensure sound management.

“It is vital that we manage our fisheries to balance the needs of the ecosystem, human nutrition and coastal communities, ” said Andrew Mallison, IFFO Director General. “These findings give fishery managers guidance based on science, and update some of the inaccurate conclusions of previous reports. ”

The Lenfest findings were largely based on a model called EcoSim, developed by Dr. Carl J. Walters, one of the co-authors of the new paper. Dr. Walters found that the EcoSim models used in earlier studies had omitted important factors, including natural variability, recruitment limitations and efficient foraging of predators.

Dr. Walters noted that there were “very specific” issues with previous uses of the EcoSim model. “It was predicting much higher sensitivity of creatures at the top of the food webs to fishing down at the bottom than we could see in historical data, ” he said.

This is not the first time ecosystem models used in earlier studies have been questioned. One year after the Lenfest study was completed, two of its authors, Dr. Tim Essington and Dr. Éva Plagányi, published a paper in the ICES Journal of Marine Science where they said, “We find that the depth and breadth with which predator species are represented are commonly insufficient for evaluating sensitivities of predator populations to forage fish depletion. ” The new study reaffirmed this finding, noting “several reasons to concur with the conclusion that the models used in previous analysis were insufficient. ”

In addition to its critiques of previous research, the researchers found further evidence of the lack of fishing impact on forage fish. Their research indicated that environmental factors are often much more important drivers of forage fish abundance. They also found that the distribution of forage fish has a greater impact on predators than simply the raw abundance of forage fish.

The authors concluded by noting the importance of forage fish as a part of human food supply chains, praising their high nutritional value, both through direct human consumption and as food in aquaculture, as well as the low environmental impact of forage fishing. Cutting forage fishing, as recommended by the Lenfest group, would force people to look elsewhere for the healthy protein and micronutrients provided by forage fish – likely at much greater environmental cost, the authors wrote.

“Forage fish provide some of the lowest environmental cost food in the world – low carbon footprint, no water use, ” Dr. Hilborn said. “[There are] lots of reasons that forage fish are a really environmentally friendly form of food. ”

It is also well-established that forage fisheries provide substantial health benefits to human populations through the supply of long chain omega-3 fatty acids, both directly through consumption in the form of fish oil capsules, and indirectly through animal feed for farmed fish and land animals.

This story originally appeared on Seafoodnews.com, a subscription site. It is reprinted with permission.