Nutritional quality variation in Atlantic Herring:
and seabirds, and are also the target of several major fisheries (purse seiners, weirs) for human consumption. Despite the ecological and economic importance of Atlantic herring, robust temporal and ontogenetic data quantifying the variation in the nutritional value of these fish does not exist. The main goal of the GMWSRS’ investigation of the nutritional quality of Atlantic herring is to quantify the temporal and ontogenetic variation present in this important prey item.
Hillary Lane, a graduate student at the University of North Carolina Wilmington from 2007-2009, carried out this work. The complete results of her project are available in the publications section of the website (Lane et al. 2011). The abstract of her paper summarizes the study: Atlantic herring collected from 2005 through 2008 from
the Bay of Fundy, Canada, were examined for variability in their nutritional quality by using total lipid content (n=889) and fatty acid composition (n=551) as proxies for nutritional value. A significant positive relationship was found between fish length and total lipid content. Atlantic herring also had significantly different fatty acid signatures by age. Fish from 2005 had significantly lower total lipid content than fish from 2006 through 2008, and all years had significantly different fatty acid signatures. Summer fish were significantly fatter than winter fish and had significantly different fatty acid signatures. For all comparisons (ontogenetic, annual, and seasonal) percent concentrations of omega-3, -6, and long-chain monounsaturated fatty acids were the most important for distinguishing between the fatty acid signatures of fish. This study underscores the importance of quantifying variation in prey quality synoptically with prey quantity in food webs over ontogenetic and temporal scales when evaluating the effect of prey nutritional quality on predators and on modeling trophic dynamics.