THE OCCURRENCE OF CHARACTERISTIC DEFORMITIES IN THE CHIRONOMID LARVAE OF SEVERAL CANADIAN LAKES

Abstract

Severely deformed chironomid larvae have been collected in Lake Erie and two lakes in the Okanagan valley of British Columbia. Deformed larvae had very aberrant mouthparts and the head capsules were usually heavily pigmented. In most cases both the head capsule and body wall were many times thicker than in normal specimens. These deformities are apparently caused by pollutants and it is speculated that agricultural and/or industrial chemicals may be responsible.