As an indirect method of diet analysis, fatty acid profiles have quickly garnered much interest by ecologists. However, interpretations of trophic connections from fatty acids may differ depending on tissue type and its lipid content. To investigate differences between tissues sampled, muscle plugs and belly flaps were taken from lake trout caught in Lakes Champlain, Ontario, Michigan, Swan, and Flathead. Fatty acid profiles of each tissue were used to evaluate foraging differences among lake trout populations. Tissue specific fatty acid profiles were most similar when lipid content of muscle samples was >10 %, similarities dropped precipitously below this level. In general, fatty acid profiles were specific toeach lake, indicating that food web structure was distinct in each lake. Fatty acid profiles indicated that lake trout from Lake Champlain were highly piscivorous, compared to similarly size fish from other lakes. Indicators of bacterial trophic connections were higher in lake trout from Lake Ontario than other lakes. Tissues of higher fat content (i.e. adipose) likely offer greater insights into dietary changes vs. tissues of greater membrane concentrations (i.e. muscle). Further investigations linking fatty acids to diets of species across spatially disparate systems could greatly enhance trophic indicator development.
|Original language||English (US)|
|Title of host publication||Great Lakes Solutions: Integrating Across Disciplines & Scales|
|State||Published - 2016|