This January, Naomi
Pleizier returned to the Cape Eleuthera Institute, The Bahamas, to continue her M.Sc. research on the effects of cortisol on the personality and condition of checkered pufferfish (Sphoeroides testudineus). Checkered puffers are not only charming but also amazingly resilient, having evolved to withstand the large fluctuations of temperature and salinity that routinely occur in mangrove ecosystems. Although these fish are incredibly robust, additional stressors may nevertheless have negative effects on the puffers’ condition and behaviour.
One such effect of stress can be to alter the expression of animal personality. “Animal personality” is the structured differences in the behaviours of individual animals across time and context. Such behavioural differences can include shyness and boldness, exploration, and activity. Personalities can influence how animals interact with their environment and other organisms. Stress can amplify, attenuate, or have no influence on personality.
Naomi and her team used experimental cortisol manipulations (a stress hormone) to determine the effect of this elevated cortisol level on various predator avoidance behaviours in checkered puffers, including the well-known “puff”. They also determined whether the observed behaviours constitute personality types.
Many thanks to Ian Bouyoucos, Aaron Schultz, Jake Brownscombe, Alex Wilson, Steven Cooke, and the whole CEI team for all their help in the field and the lab!
