Bathythermal Habitat Use by Strains of Great Lakesand Finger Lakes-Origin Lake Trout in Lake Huron after a Change in Prey Fish Abundance and Composition

Author(s):

Charles Krueger, William W. Taylor, Roger A. Bergstedt, Ray L. Argyle

Journal or Book Title: Transactions of the American Fisheries Society

Volume/Issue: 141:2

Page Number(s): 263-274

Year Published: 2012

Abstract:

A study conducted in LakeHuron duringOctober 1998–June 2001 found that strains ofGreat Lakes-origin (GLO) lake trout Salvelinus namaycush occupied significantly higher temperatures than did Finger Lakes-origin (FLO; New York) lake trout based on data from archival (or data storage) telemetry tags that recorded only temperature. During 2002 and 2003, we implanted archival tags that recorded depth as well as temperature in GLO and FLO lake trout inLake Huron. Data subsequently recorded by those tags spanned 2002–2005. Based on those data,we examined whether temperatures and depths occupied by GLO and FLO lake trout differed during 2002–2005. Temperatures occupied during those years were also compared with occupied temperatures reported for 1998–2001, before a substantial decline in prey fish biomass. Temperatures occupied by GLO lake trout were again significantly higher than those occupied by FLO lake trout. This result supports the conclusion of the previous study. The GLO lake trout also occupied significantly shallower depths than FLO lake trout. In 2002–2005, both GLO and FLO lake trout occupied
significantly lower temperatures than they did in 1998–2001. Aside fromthe sharp decline in prey fish biomass between study periods, the formerly abundant pelagic alewife Alosa pseudoharengus virtually disappeared and the demersal round goby Neogobius melanostomus invaded the lake and became locally abundant. The lower temperatures occupied by lake trout in Lake Huron during 2002–2005 may be attributable to changes in the composition of the prey fish community, food scarcity (i.e., a retreat to cooler water could increase conversion efficiency), or both.

DOI: 10.1080/00028487.2011.651069

Type of Publication: Journal Article

Publisher: Taylor & Francis

Location: London

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