Swimming behavior of newly hatched larvae of six decapod species (Crustacea: Decapoda)

Abstract

Crustacean decapod larvae have developed several adaptations to maximize their survival, including swimming behavior. Swimming improves larvae dispersal and contributes to their response to environmental stresses, including variations in abiotic factors, presence of predators, and search for food. Data on larval behavior can also assist in studies on conservation and in species management in aquaculture. Unfortunately, swimming behavior remains unstudied in many species. The present work aims to analyze the swimming behavior in newly hatched larvae of six common decapod crustaceans in coastal Southeast Brazil (Macrobrachium acanthurus, Macrobrachium olfersii, Emerita brasiliensis, Ucides cordatus, Minuca rapax, and Callinectes danae). The analysis included tests with larval responses to four isolated stimuli: gravity (geotaxis), vertical salinity gradients, low-pressure zones, and presence of the planktivorous fish, Atherinella brasiliensis (only for C. danae and M. rapax). The first two and the last two stimuli were used as indicators of dispersal and defensive behaviors, respectively. All larvae