Do prey resources explain differential habitat use of age-0 yellow perch and bluegill?

Spatial overlap between age-0 fishes and prey resources are beneficial for growth and subsequent recruitment.  Our objectives were to determine if age-0 bluegill and yellow perch relative abundance and mean length differed among four habitat types.  If differences were detected, we then wanted to relate these differences to prey availability.  A total of four different habitat types (Scirpus spp., Phragmites australis, Typha spp., open water) were sampled for age-0 fishes during daytime and nighttime using cloverleaf traps in August, September, and October.  Benthic invertebrate and zooplankton samples were also collected each month.  Bluegill catch per unit effort (CPUE) was lower in open water habitats compared to vegetated sites.  Conversely, yellow perch CPUE was greatest in open water sites compared to Phragmites australis and Typha spp. habitats, but not different than Scirpus spp. habitats in August.  Cladoceran and copepod densities were greatest in the open water habitats compared to most of the vegetated sites.  Habitats containing higher bluegill CPUE were not associated with the highest zooplankton densities; however, yellow perch CPUE appeared to overlap more with prey resources in August.  The lack of relationship between bluegill CPUE and prey resources may reflect a behavioral component such as predator avoidance.