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... In a recent paper on ecosystem function and services of aquatic predators in the Anthropocene [1], Hammerschlag and colleagues highlight a set of 16 outstanding research needs, including strengthening our understanding of the mechanisms and extent to which aquatic predators influence micronutrient and trace element fluxes within ecosystems. Závorka et al. [2] persuasively point out that within the realm of micronutrients, there is strong evidence that aquatic predators play a central role in the transfer of essential fatty acids (EFAs) such as docosahexaenoic acid (DHA, 22:6ω3) and eicosapentaenoic acid (EPA, 20:5ω3) in food webs, and that EFAs are vitally important neurologically for many consumers including humans. We agree that EFAs are an exciting and significant area of research, and we embrace their suggestion to extend the social and ecological framework presented in [1] to incorporate what is known about fluxes of EFAs as micronutrients. ...
... Závorka et al. [2] correctly emphasize how the decline of predators in aquatic food webs has critical implications for human health through the loss of vital sources of micronutrients such as EFAs. Indeed, aquatic predators represent a key provisioning ecosystem service via linkages with human nutrition, which serves as a major rationale as to why further research aimed at elucidating mechanisms and extent to which aquatic predators influence micronutrients and trace element fluxes within ecosystems is an urgent priority [1]. ...
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