Recent increases in the extent and duration of hypoxia in Lake Eries central basin potentially threaten the production of economically and ecologically valuable fish species, such as yellow perch (Perca flavescens) and rainbow smelt (Osmerus mordax). We used limnological hindcasts (1987-2005) to evaluate the negative effects of hypoxic conditions on yellow perch and rainbow smelt habitat quality. We generated spatio-temporally explicit estimates of bioenergetic growth rate potential (GRP) to identify inter-annual variability in the quality of yellow perch and rainbow smelt habitat. We expected hypoxia to have a greater negative impact on habitat quality for rainbow smelt compared to yellow perch due to species-specific differences in oxygen and temperature tolerances. Indeed, yellow perch demonstrate positive GRP values across a broader range of depths than rainbow smelt, which are less tolerant of warm, epilimnetic water temperatures and low, hypolimnetic dissolved oxygen levels. To assess whether hypoxia appears to have any population-level effects on recruitment of both species, we related annual indices of habitat quality to fisheries independent estimates of year-class strength and recruitment to the fishery.

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