Similar to how children learn, often unconsciously, to mimic the adults around them, a small, silvery ocean fish employs this tactic when teaching the next generation to find a suitable place to reproduce.
Scientists have named the strategy "go with the older fish,” and it describes a key part of the Pacific herring lifecycle that has been recognized for years by indigenous peoples, but hasn’t factored into management of the species.
As juveniles, herring join large schools offshore to mingle, eat and grow until it’s time to reproduce. Then, younger, smaller herring follow the older, more experienced fish back to specific beaches to spawn. It appears none of the fish are aware of this learning process; rather, the memory of where to go is imprinted unconsciously into their brains.
Herring migration isn’t random, and this could also explain why herring have been missing for years from some beaches, even in the few cases where the overall population numbers are adequate. If older fish that spawned at a specific beach are wiped out, there are no fish to lead the next generation to use that particular site.
This realization could entirely change how these fish are managed, and aid in restoring some of the spawning populations now absent from many of the beaches along the west coast of British Columbia and Alaska.
"The herring are very important to our people,” said Harvey Kitka, an elder and former tribal council member with the Sitka Tribe of Alaska. "Spawning was a huge event each spring, and probably for thousands of years herring spawned in the same area in Sitka Sound.”
This shift in thinking happened because a diverse group of people, including tribal leaders such as Kitka, ecologists, biologists, anthropologists, fishery managers and commercial fishers, met to talk about how to save Pacific herring, a fishery that is vital to native communities and the commercial fishing industry. Facilitated by the Ocean Modeling Forum - a collaborative group led by the University of Washington - they tackled difficult management questions, and ultimately produced a number of scientific papers and tools released this winter that will help guide the recovery and management of herring going forward.
"During our conversations, it became very clear that herring and humans are really tightly coupled, and that’s true whether you’re a commercial fisherman, a vessel owner or a traditional harvester,” said Tessa Francis, managing director of the Ocean Modeling Forum and lead ecosystem ecologist with the Puget Sound Institute at UW Tacoma. "This was an opportunity for us to think about different forms of knowledge and alternative models in a situation related to fishery management.”
The Ocean Modeling Forum kicked off the project in June 2015 with a summit in British Columbia, with the goal of hearing from a number of stakeholders, tribes and First Nations about the role herring plays socially and ecologically, and to begin to develop a framework for how different approaches and knowledge - including traditional ecological knowledge - can be used in fisheries management practices.
The meeting came at a time when the Pacific herring fishery was fraught with disagreements about fishing practices, including along the archipelago of Haida Gwaii off British Columbia’s west coast. There, First Nations leaders have argued that the herring population, which holds deep cultural significance, hasn’t yet recovered to a healthy level capable of sustaining a fishery. This is true particularly at individual spawning beaches that are significant for First Nations communities, where some fish have never returned to their previous numbers.
Meanwhile, Fisheries and Oceans Canada has considered opening the fishery to commercial fishing in recent years. They find the overall population in some areas to be strong, but managers aren’t considering the finer-scale patterns of sub-populations that spawn at individual beaches.
Tribes and First Nations people harvest herring eggs on kelp or tree branches, traditionally at specific beaches using small boats, and make considerable efforts not to disturb the spawning fish. This approach is in stark contrast to commercial fishing vessels that target schools of fish and can move around to where they are any given year. As a result, the current management approaches are tailored to commercial fishing, as long as there are fish to catch.
Against this backdrop, the Ocean Modeling Forum wanted to offer a different approach: One that put local beaches back at the center of the conversation, and joins traditional knowledge with science.
"Our working group was born on the idea that where the fish are is just as important as how many fish there are. Herring used to be the life force of the indigenous villages in the spring,” said Phillip Levin , co-director of the initiative who also holds a joint role as a UW professor of practice and lead scientist with the Nature Conservancy of Washington. "For herring management to be successful, it must address problems at the scale that impacts the well-being of the people who depend on the fish.”
After the initial herring summit drew 150 people, a smaller group of about two dozen set to work on addressing the main priorities raised in the summit. The outcome of this working group is a set of research papers, fact sheets and modeling tools released this winter that agencies can use to incorporate local-scale dynamics, traditional knowledge and human dimensions, such as the cultural significance of fishing, into Pacific herring management.
Notably, one of the main results was the "go with the older fish” interpretation of herring biology, explained in a recent scientific paper , which will likely impact how these fish are managed. This idea has been used in European herring fisheries, but this is the first time it’s been applied in ways that could recover and sustainably manage herring in North America.
"I hope we can get managers to look at this and at least give it a try,” Kitka said. "It’s so important to us. From the time they’re an egg to when they disintegrate, herring are food for something.”
The origins of this paper are representative of the overall goal of the Ocean Modeling Forum: By bringing together experts from many backgrounds, the idea was hatched while Kitka, a long-time fisherman and tribal elder, traded stories one morning with Alec MacCall, a long-time scientist and fisheries researcher. They realized that patterns they had both seen over the years overlapped to illuminate key aspects of herring biology.
"Progress in science can be much less certain than is the popular understanding of how it works. When a new approach or theory seems to answer questions beyond those that were initially posed, it feels like we may be on the right track,” said MacCall of the Farallon Institute for Advanced Ecosystem Research in California. "The path to healthy herring stocks is neither easy nor clear, but we may be getting a better sense of its direction.”
The Ocean Modeling Forum has been asked to participate in a new herring rebuilding strategy process for Haida Gwaii, which just launched among Fisheries and Oceans Canada, the Haida Nation and Parks Canada. At the group’s first meeting this winter, accounting for the differences between where traditional and commercial harvest practices occur and the "go with the older fish” idea were central to their conversation, which is a positive sign that the thinking around herring management already is changing, Francis said.
"It’s hard to underestimate the value of showing respect for traditional knowledge and incorporating it into management practices,” Francis said. "One major impact the Ocean Modeling Forum has is to influence the decision-making process by changing people’s minds and developing tools that can be directly used.”
The Ocean Modeling Forum’s next major project is looking at ways to use scientific tools and modeling approaches to reduce the number of marine mammals accidentally caught during commercial fishing.