EFFECTS OF SUBMERGENCE BY WINTER FLOODS ON DIAPAUSING CATERPILLARS OFA WETLAND BUTTERFLY, LYCAENA DISPAR BATAVUS

1. The influence of seasonal flooding on wetland insects is understudi ed, and understanding of a potentially important influence on populati on dynamics is therefore incomplete. This is of particular consequence because many wetland insect species, including the large copper butte rfly, Lycaena dispar batavus, are of conservation interest. 2. Previou s studies on the submergence tolerance of diapausing L. d. batavus lar vae have been inconclusive. This study investigated the effects of dif ferent periods of enforced submergence on overwintering survival, usin g both fresh and brackish water, and comparing effects on larvae in ea rly and late diapause.3. Larvae were submerged for up to 84 days, and survival was negatively correlated with submergence period, although p eriods of up to 28 days did not appear to reduce survival. Water type, i.e. fresh vs. brackish water, and larval stage, i.e. early vs. late diapause, had no significant influence on survival. 4. The relevance o f these findings to the population biology and conservation of L. d. b atavus is discussed. Further studies on the effects of submergence by seasonal flooding on wetland insect populations are encouraged.