Seasonal dynamics and spatial distribution of Urocleidus ferox Mueller 1934, a gill parasite of Lepomis gibbosus (L.)

Abstract

Seasonal dynamics and spatial distribution were determined for Urocleidus ferox Mueller 1934, a gill parasite of Lepomis gibbosus (L.). Twenty-five specimens of L. gibbosus from eutrophic (West Lake) and 25 specimens from oligotrophic (Glenora) habitats were examined monthly between November 1971 and October 1972.The data were analysed using a two-factor ANOVA and Duncan's multiple range test.High abundance levels of U. ferox were recorded in both localities throughout the sampling period. The peak was reached in July 1972 and the lowest levels recorded in November 1971 in both localities. The eutrophic habitat, West Lake, was significantly (P < 0.001) more favourable for U. ferox than the oligotrophic one, viz. Glenora.The anterior side of hemibranchs and their medial sections were preferred sites of infection (P < 0.001); gill arches two and three were found to be preferred sites of infection (P < 0.001) for U. ferox.