North Pacific Anadromous Fish Commission

Technical Report 18

Table of Contents

Environmental DNA Survey of the Winter Salmonosphere in the Gulf of Alaska

Christoph M. Deeg, Svetlana Esenkulova, Shaorong Li, Brian P.V. Hunt, Ben J.G. Sutherland, Angela Schulze, and Kristina M. Miller

Abstract Excerpt:
Environmental DNA (eDNA) is an emerging field to study the diversity and distribution of aquatic communities without the need to capture individuals. It utilizes sequencing of traces of DNA left behind in the environment by organisms to provide an unbiased account of species composition and distribution in an environment without the need for invasive sampling methods (Rees et al. 2014). The International Year of the Salmon (IYS) Gulf of Alaska (GoA) expeditions were launched in 2019 and 2020 to illuminate the factors influencing the survival of Pacific salmon in the open ocean. The winter months, when open-ocean conditions might critically impact ocean survival of first ocean-winter juvenile and subadult salmon, are the least understood but could largely determine stock performance (Beamish and Mahnken 2001; Naydenko et al. 2016; Shuntov et al. 2017; Nagasawa 2000; Ishida et al. 2000). Despite progress on salmon marine ecology during the winter, questions regarding the health and survival of salmon during this period remain unanswered, particularly in the open ocean. Specifically, the impact of predators and competitors has been notoriously difficult to assess due to the scarcity of data, in part due to the difficulty of catching large highly mobile predators of salmon in trawl surveys. Accordingly, we collected water samples during the GoA expeditions and performed an eDNA survey on the samples with the goal of describing the salmonosphere (i.e., the relative abundance and distribution of Pacific salmon, as well as their prey, competitors, and predators).



Deeg, C.M., S. Esenkulova, S. Li, B.P.V. Hunt, B.J.G. Sutherland, A. Schulze, and K.M. Miller.  2022.  Environmental DNA survey of the winter salmonosphere in the Gulf of Alaska.  N. Pac. Anadr. Fish Comm. Tech. Rep. 18: 37–41.