Captive breeding of odonate larvae: Effects of type of water, handling, and sex

Abstract

AbstractBasic information on life histories, ecology, and behaviour for aquatic stages in many species of insects is difficult to obtain in the field. Here, a method to breed and monitor individual Odonata larvae in captivity is proposed. In total, 3788 individuals of six Odonata species – Rhionaeschna marchali (Rambur), Erythrodiplax abjecta (Rambur), Sympetrum gilvum (Selys), Ischnura chingaza Realpe, Ischnura cruzi De Marmels, and Mesamphiagrion laterale (Selys) – were reared individually in water‐filled plastic containers, whose size was increased to fit larval growth, at ambient temperature (12–34 °C, 12 h light per day, ca. 300 lux, and ad libitum food). We tested the effects of water type (habitat water, dechlorinated tap water, and drinking water), handling method, and sex on larval developmental time and number of instars. The number of instars was calculated as the mean number of moults for the individuals that successfully emerged as adults. Life cycle length was calculated by averaging the days over individuals that completed their development until emergence. The probability of achieving the adult stage was not significantly affected by the type of water, sex, or handling method. On the other hand, the number of instars was affected by species identity, and type of water, with fewer instars in water from the natural habitat, but not affected by sex or handling method. The duration of the life cycle was bimodal in most species, and was affected by type of water, but in an idiosyncratic, species‐specific way. The methodology proposed here allows monitoring and breeding large numbers of odonate larvae.