ORGANIZATION OF CRUSTACEAN EPIZOAN COMMUNITIES IN A CHAIN OF SUB-ALPINE PONDS

Crustacean zooplankton in high altitude ponds in Colorado support two suites of epizoans. Epizoans on Daphnia consisted of Colacium calvum, Characium gracilipes, and peritrich ciliates. Epizoans on Ceriodaphnia, Scapholeberis, and Eucyclops involved Colacium vesiculosum and the peritrich ciliates. Frequent, regular molting of most of the substrate organisms keeps attachment surfaces unoccupied. Epizoan attachment is site-specific rather than a function of epizoan-epizoan interaction. The presence of phototrophic epizoans may contribute to increased susceptibility of their substrate organisms to fish predation.