MEPS 473:247-260 (2013)  -  DOI: https://doi.org/10.3354/meps10095

Ecosystem-level consequences of movement: seasonal variation in the trophic impact of a top predator

Kelly S. Andrews*, Chris J. Harvey

Conservation Biology Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd E, Seattle, Washington 98112, USA

ABSTRACT: Spatio-temporal patterns of species abundance influence the strength of trophic interactions, while movement of individuals helps determine those patterns of abundance. Thus, understanding movement is a basis for quantifying interactions within a food web. In Puget Sound, Washington, USA, the North Pacific spiny dogfish Squalus suckleyi is an abundant top predator with a diverse, generalist diet. Coastal dogfish populations make seasonal north−south migrations, but populations in inland waters are thought to be more resident. In this study, we combined acoustic telemetry and bioenergetics modeling to determine patterns of movement and to quantify seasonal variation in the predatory impact of dogfish in Puget Sound. All tagged dogfish migrated out of Puget Sound in the winter and were absent until the following summer. Individuals that returned to Puget Sound in subsequent years showed consistent timing and duration of residence across years, but these metrics varied across individuals. Incorporating movement data into the bioenergetics model resulted in a 70% decrease in the predatory impact of dogfish in the winter and a 30% decrease in the summer, compared to a year-round resident Puget Sound population. Incorporating metrics of movement into food web or ecosystem models will increase our understanding of species interactions and will improve our ability to predict changes in food web dynamics under various environmental and management scenarios.


KEY WORDS: Acoustic telemetry · Bioenergetics · Migration · Tagging · Movement · Squalus suckleyi · Squalus acanthias


Full text in pdf format 
Cite this article as: Andrews KS, Harvey CJ (2013) Ecosystem-level consequences of movement: seasonal variation in the trophic impact of a top predator. Mar Ecol Prog Ser 473:247-260. https://doi.org/10.3354/meps10095

Export citation
Mail this link - Contents Mailing Lists - RSS
- -