Benefits of Turbid River Plume Habitat for Lake Erie Yellow Perch (Perca flavescens) Recruitment Determined by Juvenile to Larval Genotype Assignment.

Nutrient-rich, turbid river plumes that are common to large lakes and coastal marine ecosystems have been hypothesized to benefit survival of fish during early life stages by increasing food availability and (or) reducing vulnerability to visual predators. However, evidence that river plumes truly benefit the recruitment process remains meager for both freshwater and marine fishes. Here, we use genotype assignment between juvenile and larval yellow perch (Perca flavescens) from western Lake Erie to estimate and compare recruitment to the age-0 juvenile stage for larvae residing inside the highly turbid, south-shore Maumee River plume versus those occupying the less turbid, more northerly Detroit River plume.

Novel molecular approach demonstrates that turbid river plumes reduce predation mortality on larval fish.

Turbidity associated with river plumes is known to affect the search ability of visual predators and thus can drive 'top-down' impacts on prey populations in complex ecosystems; however, traditional quantification of predator-prey relationships (i.e. stomach content analysis) often fails with larval fish due to rapid digestion rates.