What is a forage fish? What is its intrinsic value? How should we manage these populations given the significant ecosystem, economic and social importance of the fishery? These questions are particularly relevant considering the fishery accounts for anywhere between a quarter and a third of the global seafood harvest. Those are some of the questions discussed during a very fluid, informative session at the 2015 SeaWeb Seafood Summit.
Definition and ecosystem value
Konstantine Rountos, a marine ecologist and conservation scientist with the Institute for Ocean Conservation Science at Stonybrook University, said there is no one distinct definition of forage fish, which could pose some challenges in terms of management. “One consistency is their important role in transferring energy from plankton to upper trophic level predators,” he said.
But then California rockfish could be considered forage fish when small, but certainly not when they grow much bigger, he said. “Perhaps the definition is something that stays predated upon throughout its lifecycle, like menhaden.” Either way, defining forage fish adequately and consistently is essential to effective management.
Rountos described the paradox of the forage fish natural defense mechanism. You may well have seen pictures or videos of bait balls of thousands of herring swimming in a ball at high speed. This ball in motion distracts predators, often preserving a good portion of the school. But that very same schooling tactic makes them much more vulnerable to being scooped up in a net en masse.
Rountos then shed light on the ecosystem impacts of forage fish depletion. He said the most immediate impact is a lower quality nutrient intake for marine predators and seabirds, which are particularly susceptible to forage fish declines because “they’re essentially eating junk food,” he said.
Additionally, that could lead to a boom in other species such as jellyfish that compete with forage fish for zooplankton food resources. However, jellyfish are not as ecologically valuable because they don’t transfer energy up the food chain, he said. They don’t have as many natural predators.
All of this variability suggests how important forage fish are to various ecosystems, which means management should take into account the most critical factors affecting forage fish sustainability. For example, Rountos referred to recent management recommendations in California that state that fishing for forage species should be restricted where there isn’t a thorough understanding of the predators that depend on those species.
- 15 million tons of whole forage fish yield 5 million tons of fishmeal annually, while 7 million tons of forage fish byproducts yield 1 million tons of fish oil.
- Of the 5 million tons of fishmeal produced annually, 3.2 million tons goes to aquaculture, while 1.3 million tons go to pig feed, and .5 million tons go to chickens.
- The 3.2 million tons of fishmeal for aquaculture yields 35 million tons of farmed fish today. By comparison, in 2000, 2.5 million tons of fishmeal produced 15 million tons of fed aquaculture.
- The 1.3 million tons for pig feed yields 150 million tons of pork products.
- The .5 million tons going into chicken feed yields 110 million tons of poultry.
- Direct human consumption of fish oil increased from 50,000 tons in 2000 to 200,000 tons today. Fish oil produced for aquaculture dipped slightly from 800,000 tons to 750,000 tons, in the same time period. Fish oil produced for salmonid farming alone dropped from 600,000 tons to 500,000 tons.
- During the same timeframe, overall salmonid production increased from 1.5 million tons to 3 million tons.
In short, Jackson made the point that forage fish comprise a critical staple in fish, pig, chicken and human (in dietary supplements) diets. For example, he said that if the fishmeal production industry were to be shut down, the implications on pig and chicken farming, not to mention aquaculture, would be significant. Even fish that are herbivorous as adults are carnivorous as fry, so any farmed fry rely on fishmeal to grow, he said.
Interestingly, he added that if fishmeal production stopped, Alaskan wild salmon would also suffer because those fish have become dependent on young hatchery-released fry. For all of these reasons, proper management is paramount, he said.
Need for more collaboration
Barton Seaver is a chef and author who champions seafood sustainability and the relationships seafood systems create between us and our food, and those who produce it. In his view, the forage fishery’s relative health hinges on better collaboration between fishermen, industry, marine biologists and consumers.
To understand the relationship between us and seafood, we need to understand how our perception of seafood has changed. He pointed to a University of Washington study that notes historically, we tended to eat more of the seafood that swam toward us, such as herring, mackerel and other forage fish. “The best went to fish oil, the next best into tomato sauce and the rest to sardines,” he said.
Over time, that dynamic changed, and we now eat more seafood that we “chase” on the high seas, he said. That seafood is harder to catch, costs more and has fewer overall numbers than forage fish. It is also the seafood that most often crops up in today’s cookbooks, which is a big change from 100 years ago. He pointed to the “sad tale of the canneries” in Monterey Bay that were shut down after World War II because of a combination of overfishing of the regional forage fish, changing marine ecosystems and global competition.
Seaver remarked on how the economics around forage fish have changed in time by describing a visit to a couple of warehouses in Peru processing forage fish for different purposes. In one warehouse, “tens of thousands of pounds” of forage fish were being ground up for low-profit fish meal in a plant employing about 25 people. In another plant, 150 people worked to process 2,000 pounds of fish for fish oil at a higher margin than the fertilizer.
“Current forage fish participants are rather divorced [from the notion] that they’re part of a food system,” he said. “Herring fishers selling to lobstermen [as bait] aren’t really concerned with herring’s possibility as a food fish.” He likened the situation to corn growers in the ethanol industry.
“We’re not working collaboratively,” he said. “We should be catching less for greater value for a greater purpose.”
Jackson said collaboration needs to be global as well as local, pointing to China’s annual “exploitation” of an estimated 5 million tons of whole forage fish of different species fed wholesale to farmed grouper, croakers and other fish in pens. International collaboration, even just abiding by the Food and Agriculture Organization of the United Nations standards, would be a significant step in the right direction, he said.
Rountos agreed. “Having industry, NGOs [non-governmental organizations] and scientists in the same rooms and talking is huge.”
We need more scientists involved in these discussions to get the message out.”
Check out the “Little Fish Big Impact” report by the Lenfast Forage Fish Task Force.