Which factors explain lepidopteran larvae variance in seasonal guilds on some oaks?

Abstract

Differences between the oak lepidopteran communities were studied in Slovakia in 1993 and 1994. Sampling was undertaken between April and October on 3 oak species. Biological traits of larvae were examined in order to explain differences in seasonal guilds among oaks. Cluster analysis shows similarities between communities in the flush feeder guild where the results were influenced mainly by temporal variability; in the late spring guild mainly by site; factors influencing summer feeder and autumn feeder similarities remain unclear. Detrended Correspondence Analysis (DCA) was used to investigate the main gradients explaining variability in communities. Results indicated that the host specificity along axis 1 (Al) and larval ballooning along axis 2 (A2) were important in the flush feeder guild; larval feeding strategy along Al and the degree of defoliation by Lymantria dispar along A2 were important in late spring feeders; the year of study along Al and host specificity along A2 were important in the summer feeder guild; and adaptation to lower quality of food along Al and host specificity along A2 for the autumn feeder guild. The results are discussed.