Due to the long journeys salmon undertake at sea, scientists studying the decline of B.C.’s populations have struggled to understand the late marine phase of their life cycle. But a new database from UBC researchers aims to change that by offering a window into the diets and lives of these fish as they travel thousands of kilometres through different ecosystems and conditions.
“It’s about fitting the puzzle pieces together to see what conditions these fish face in the open ocean, and answering questions like: what food is available for them? Is there competition for this food? How does this relate to environmental variability and salmon returns?” said Caroline Graham, a graduate of UBC’s Institute for the Oceans and Fisheries’ master of science program.
Graham built the database as part of her Master’s thesis with researchers Brian Hunt and Evgeny Pakhomov. What’s called the open-access salmon diet database is part of a larger undertaking, Project Salmon Resilience, that aims to explore the impacts of fisheries and climate change on salmon populations.
Graham spent months combing through both peer-reviewed and non-peer reviewed studies from countries across the North Pacific, translating the data into a standardized format that could be replicated for use in diet data collection for other fish species.
The work is already paying off.
“What we’re seeing is that different species of salmon have different dietary habits. These differences tell us a lot about not only the ocean conditions but also competitive interactions between species of salmon, and how this plays out on a spatial scale,” Graham said.
The team hopes the database will bring the research community closer together as scientists add their own findings.
“There are a lot of other species of fish out there,” Brian Hunt, assistant professor and UBC Hakai professor of oceanography said. “We’d like to expand this database to more species and liberate diet data that are lurking in the literature or with agencies to make it available to the community. Everyone talks about ecosystem-based management, and to do that you really need to understand the interactions between animals. Most of that happens through the food web, so we need to provide access to information. Hopefully this is a small step in that direction.”