Since the early 1900's rainbow smelt (Osmerus mordax)have been introduced into many new freshwater inland systems outside of its native range. In freshwater systems the interaction between rainbow smelt and native piscivores differs from species to species. In some cases predation or competitive interactions between juvenile piscivores and adult rainbow smelt can limit recruitment success of piscivores. In other cases, rainbow smelt have no such impacts on piscivores and only serve as a forage fish. In a literature review, I exploredrainbow smeltinteractions withthree different piscivore species, Atlantic salmon (Salmo salar), lake trout (salvelinus namaycush) and walleye (Sander vitreus). Differences in larval rearing strategies were indentified as the most important factor in determining the nature of effects of rainbow smelt.In particular, larval walleye experience high levels of mortality after rainbow smelt establishment. A foraging-based bioenergetic model was created to determine if the zooplankton community that resultsfrom rainbow smeltestablishment creates an "energetic bottleneck" for larval walleye.I assessed larval walleye densities and pelagic zooplankton communities in four lakes in Northern Wisconsin with differing populations of rainbow smelt.Results indicate that rainbow smelt do not prey on larval walleye butan energetic bottleneck may exist at low zooplankton biomasses.
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