In the North Pacific, salmon are iconic fish that play important roles in terrestrial, freshwater, and marine ecosystems, while also being culturally invaluable and economically important. Salmon have been studied widely by individual countries of the North Pacific rim with a focus on the freshwater and early marine phases of their life cycle. However, the late marine phase of their life cycle, during which they migrate thousands of kilometers through the open ocean, crossing international and ecosystem boundaries, is not well understood. The late marine phase is difficult to study due to the logistical challenges of open ocean research in a vast and dynamic region, however, the results of historic and current research expeditions have the potential to help further our understanding of the challenges salmon face in a rapidly changing climate.
Salmon diet data have been collected over the last century or so and have the potential to reveal important information about salmon and North Pacific ecosystems more generally. Salmon diets not only influence the health of salmon, but also reflect the status and composition of North Pacific ecosystems. This is because salmon are usually considered to feed broadly on all available prey, from small crustaceans to larger fish, squid, and even jellyfish. In this way, salmon can paint an overall picture of North Pacific community composition. Furthermore, studying the diets of salmon and how their diets change with ocean conditions is a key step towards understanding how salmon and North Pacific ecosystems are being affected by changing oceans. Salmon diet data can even help us understand whether these fish are facing competition from rising numbers of hatchery-produced salmon.
In our Scientific Data publication, ‘A salmon diet database for the North Pacific’, we describe the creation of a new open-access MySQL database (‘North Pacific Marine Salmon Diet Database’) to store standardized salmon diet data. This database is part of the University of British Columbia Project ‘Salmon Resilience’, funded by the Ambrose Monell and G. Unger Vetlesen Foundations. In this publication, we outline the first contribution of data to the database, which were identified through a systematic literature review targeting papers from two decades with high research activity: 1959–1969 and 1987–1997. The data from this initial contribution were stomach content data that were collected by dissecting salmon stomachs. In the future, this database will grow and be updated periodically with data from other time periods and could potentially include different types of diet data as well – such as stable isotope data, fatty acid data, and potentially others. While the database was built specifically to house salmon diet data, the database structure can fairly easily be modified to house other types of predator-prey data.
We hope that this database will encourage researchers to standardize and share their salmon diet data in order to more effectively collaborate across local, national and international scales to understand the future of salmon and North Pacific ecosystems in a time of rapid, human-induced change. This database is particularly timely due to the International Year of the Salmon initiative which runs from 2018 until 2022 with projects related to data mobilization and research on the understudied ocean phase of the salmon life cycle.
The North Pacific Marine Salmon Diet Database is publicly and freely available in a dynamic GitHub repository that will be updated periodically. The data is available in the MySQL database format or in an Excel format. The initial contribution of data described above can be found in a static figshare repository.
Scientific Data Article: Graham, C., Pakhomov, E.A. & Hunt, B.P.V. A salmon diet database for the North Pacific Ocean. Sci Data 7, 332 (2020). https://doi.org/10.1038/s41597-020-00676-y