Skip to main content
U.S. flag

An official website of the United States government

Introduced northern pike consumption of salmonids in Southcentral Alaska

July 17, 2014

The impacts of introduced northern pike (Esox lucius) on salmonid populations have attracted much attention because salmonids are popular subsistence, sport and commercial fish. Concern over the predatory effects of introduced pike on salmonids is especially high in Southcentral Alaska, where pike were illegally introduced to the Susitna River basin in the 1950s. We used pike abundance, growth, and diet estimates and bioenergetics models to characterise the realised and potential consumptive impacts that introduced pike (age 2 and older) have on salmonids in Alexander Creek, a tributary to the Susitna River. We found that juvenile salmonids were the dominant prey item in pike diets and that pike could consume up to 1.10 metric tons (realised consumption) and 1.66 metric tons (potential consumption) of juvenile salmonids in a summer. Age 3–4 pike had the highest per capita consumption of juvenile salmonids, and age 2 and age 3–4 pike had the highest overall consumption of juvenile salmonid biomass. Using historical data on Chinook salmon and pike potential consumption of juvenile salmonids, we found that pike consumption of juvenile salmonids may lead to collapsed salmon stocks in Alexander Creek. Taken together, our results indicate that pike consume a substantial biomass of juvenile salmonids in Alexander Creek and that coexistence of pike and salmon is unlikely without management actions to reduce or eliminate introduced pike.

Publication Year 2015
Title Introduced northern pike consumption of salmonids in Southcentral Alaska
DOI 10.1111/eff.12164
Authors Adam Sepulveda, David S. Rutz, Aaron W Dupuis, Patrick A Shields, Kristine J. Dunker
Publication Type Article
Publication Subtype Journal Article
Series Title Ecology of Freshwater Fish
Index ID 70132447
Record Source USGS Publications Warehouse
USGS Organization Northern Rocky Mountain Science Center