Spatiotemporal variability in energetic condition of alewife and round goby in Lake Michigan

Canadian Journal of Fisheries and Aquatic Sciences
By: , and 

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Abstract

Pelagic-oriented alewife (Alosa pseudoharengus) and benthic-oriented round goby (Neogobius melanostomus) are two important prey fishes in the Laurentian Great Lakes. In 2015, we evaluated their seasonal total energy (TE) across nine Lake Michigan transects. Round goby contained at least 48% more kilojoules of TE than alewife of equal length during spring and summer. TE varied spatially for both species, but only large alewife exhibited a consistent pattern, with higher values along the eastern shoreline. Variation in TE was not explained by site-specific prey densities for either species. Round goby energy density (ED) was higher in Lake Michigan than in central Lake Erie, but comparable to other regions of the Great Lakes. Alewife ED in 2015 was similar to that in 2002–2004 in Lake Michigan, with the exception of November (small alewife ED was 21% higher) and April (large alewife ED was 30% lower). Despite oligotrophication, our study suggests that starvation of juvenile and adults has not been directly contributing to overall declining prey fish abundance, although future research should evaluate the potential for overwinter starvation.

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Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Spatiotemporal variability in energetic condition of alewife and round goby in Lake Michigan
Series title Canadian Journal of Fisheries and Aquatic Sciences
DOI 10.1139/cjfas-2018-0391
Volume 76
Issue 44
Year Published 2019
Language English
Publisher Canadian Science Publishing
Contributing office(s) Great Lakes Science Center
Description 11 p.
First page 1982
Last page 1992
Country United States
Other Geospatial Lake Michigan