Substrate preference in immature Anisoptera of Lake Douglas

Abstract

Animals that are subject to predation must evolve strategies to avoid predators or go extinct. Those that lack the physiology to flee at high speed or employ physical defenses usually rely on methods such as burrowing or using camouflage. Dragonfly naiads, unlike their brightly-colored adult counterparts, are dully-colored and usually blend with the sandy lake bottom on which they live. Because they have a cryptic coloration, they show certain preferences and aversions to different substrate types which benefit or inhibit their crypsis. In this experiment, it was found that a group of naiads in the family Libellulidae showed preference for certain substrates over others during different times of day. Overall, Dragonfly naiads preferred cryptic substrate over the non-cryptic substrate, regardless of day or night conditions. Further studies are necessary to determine the cause of crypsis in dragonfly naiads.