The Emergence and Sex Ratio of Anax junius Drury (Odonata: Aeshnidae) in Canada

Abstract

The temporal pattern of emergence of Anax junius Drury was studied by making standardized exuvial collections in a farm pond near Montreal. Supports available to emerging larvae were restricted artificially in order to standardize the collecting area. Emergence lasted for 30 days (29 July to 27 August 1965), the peak lying between days 10 and 15; A. junius thus behaved as a “summer species” (sensu Corbet 1954). The emerging population comprised about 48% males. No adults were seen flying over the pond except during the maiden flight.