Hand feeding: A method to increase the survival rate of Orthetrum coerulescens (Odonata: Libellulidae) in outdoor enclosures

Abstract

Food intake rate and diet composition have a high impact on all organisms and affect individual fitness, fecundity and mortality. Specimens in enclosures have to be fed in an adequate way and with minimum stress for the specimens. Adult dragonflies are flying hunters. In enclosures, they are usually fed by adding different kinds of adult dipterans. In this study, I additionally fed specimens of Orthetrum coerulescens by hand. Each specimen received one house fly or up to six fruit flies per day. This was less than an adult dragonfly would normally consume; however, this additional hand feeding was enough to significantly increase the survival rate of individuals, especially within the first 12 days of adult life. The maximum life span (subadult and adult) observed was about 60 days, for both hand-fed adults and those that were not hand fed. © 2014 © 2014 Worldwide Dragonfly Association.