Organisms at the base of aquatic food webs synthesize essential nutrients, such as omega-3 polyunsaturated fatty acids (n-3 PUFA), which are transferred to consumers at higher trophic levels. Many consumers, requiring n-3 long-chain (LC) PUFA, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have limited ability to bioconvert them from the essential dietary precursor α-linolenic acid (ALA) and thus rely on dietary provision of LC-PUFA. We investigated LC-PUFA metabolism in freshwater zooplankton using stable...