Temporal changes in the fatty acid profiles of lake trout eggs from Cayuga lake

Authors: Owen Hazard, Jacques Rinchard

SUNY Campus: SUNY Brockport

Presentation Type: Poster

Location: UU 111

Presentation #: 75

Timeslot: Session C 1:45-2:45 PM

Abstract: Thiamine Deficiency Complex (TDC) affects salmonines in the Great Lakes region due to reduced thiamine concentrations, particularly in fish that feed primarily on alewife, often resulting in poor recruitment. Alewife have been a key part of the lake trout diet in Cayuga Lake since their likely introduction in the 1800s. The round goby, first detected in the lake in 2013, became widespread by 2017, likely influencing various aspects of the food web. This study compared the lipid content and fatty acid signatures (FAS) of lake trout eggs in Cayuga Lake from 2010 to 2023. Egg lipid content and FAS showed significant variation across the years, with 22:6n-3, 16:1n-7, 18:1n-9, 18:1n-7, 18:3n-3, 20:5n-3, 16:0, and 22:5n-3 being the fatty acids most responsible for these differences. In 2015 and 2016, lake trout eggs displayed distinct FAS, particularly enriched in 22:6n-3, likely reflecting a dietary shift following the spread of round goby in Cayuga Lake. This was followed by a return to a diet primarily based on alewife. These findings suggest a brief decline in the prevalence of TDC in lake trout after the introduction of round goby.