Navigating the predator gauntlet: Impacts of nearshore marine fishes on hatchery and wild juvenile salmon in Southeast Alaska Research team: Douglas Duncan (MS Student), Anne H. Beaudreau (PI) College of Fisheries and Ocean Sciences, University of Alaska Fairbanks Project Overview Hatcheries invest significant resources into salmon production to support lucrative and culturally important fisheries in Alaska. This study will provide insight into the fate of hatchery smolts by assessing the impacts of abundant predatory fish on young salmon in estuaries. The results will inform hatchery release strategies that reduce predation risk to smolts and provide an improved understanding of ecological factors that affect early marine survival of salmon. A Dolly Varden caught near the Macaulay Salmon Hatchery in the Gastineau Channel, shortly after the release of hatchery chum salmon. To the right of the Dolly Varden is a large quantity of juvenile fishes, including chum salmon, that a local fisherman removed from the stomach while cleaning his catch.
Project Outcomes and Benefits This research will result in: • An improved understanding of factors that affect early marine survival of juvenile salmon • Information on where, when, and what sizes of smolts are at highest risk of predation, which will help hatchery managers identify release strategies that improve survival of smolts. • Multiple years of data on fish abundance, diets, body size, and diversity, which will benefit researchers and agencies tasked with the management and conservation of Alaska’s coastal ecosystems. • Graduate student training and completion of a Master’s thesis and at least 1 peer‐reviewed scientific publication. • Research experience for undergraduates and community engagement in science.
Related Projects This project builds from our recently completed research on estuary ecology in the Juneau area. In Southeast Alaska, rapidly receding glaciers and changes in rainfall are impacting freshwater discharge and the transport of nutrients to coastal ecosystems. To understand how changes in watersheds will impact the nutrition and growth of nearshore marine species, we measured the extent to which juvenile salmon and other fish species rely on terrestrial, freshwater, and marine sources of organic matter. This study was funded by Alaska Sea Grant and NSF EPSCoR. The research team included Anne Beaudreau, Emily Whitney (MS Student, graduated 2016), Doug Duncan, Emily Howe (The Nature Conservancy), and Carolyn Bergstrom (UAS). Press: https://seagrant.uaf.edu/news/2015/11‐25‐ 15‐southeast‐alaska‐glacier‐estuary.php
Funding and Collaborators Funding was provided by University of Alaska Fairbanks, Alaska Sea Grant, and Douglas Island Pink and Chum, Inc. Thanks to our collaborators at the University of Alaska Southeast, the Alaska EPSCoR program, and the Age Tag Mark Lab of the Alaska Department of Fish and Game. This project is in progress and will conclude in fall 2018. For more information please contact: Anne Beaudreau, Assistant Professor University of Alaska Fairbanks College of Fisheries and Ocean Sciences 17101 Point Lena Loop Road Juneau, AK 99801 Email:
[email protected] Phone: (907) 796‐5454