Community structure and seasonal dynamics of helminth parasites in Lepomis cyanellus and L. macrochirus from Charlie's Pond, North Carolina: host size and species as determinants of community structure.

The community structure and seasonal dynamics of 16 helminth species infecting green (Lepomis cyanellus) and bluegill (L. macrochirus) sunfishes in Charlie's Pond, North Carolina, was examined. One hundred and fifty-four fishes including 90 green sunfish and 64 bluegill sunfish were collected between March and November 2000 and examined for the presence of helminth parasites. Five of these species underwent significant changes in abundance in green sunfish infracommunities, 3 of which also displayed seasonal changes in prevalence. Three of the 16 species fluctuated seasonally in bluegill infrapopulations; 2 also underwent changes in prevalence. Species richness and diversity varied across the 9-mo period for both host species, whereas total helminth abundance remained constant. Analysis of component communities revealed differences in community structure for the 2 host species. Bluegills were found to harbor larger and more diverse communities. Bluegills also contained larger infrapopulations of 5 species, whereas green sunfish had greater abundance of 2 species. Interpretation of these data suggests that host species and size are strongly associated with the predictability of community structure.