Maladaptive behavioural phenotypes in captive-reared darters (Etheostoma caeruleum, Storer 1845)
The foraging and anti-predator behaviour of captive-reared rainbow darters (Etheostoma caeruleum) was compared to their wild-caught counterparts. Wild-caught darters responded with appropriate anti-predator behaviour (reduced foraging activity) when exposed to alarm cues (e.g. stimuli from damaged skin) from both wild-caught and captive-reared darters, indicating that the diet in captivity did not inhibit the production of alarm cues. Captive-reared individuals did not change their level of activity when exposed to alarm cues; however, their significantly lower baseline activity (movement and prey consumption) makes it unclear as to whether they actually failed to recognize risk. Regardless, captive-reared darters showed little motivation to feed when food became available (i.e. they made few movements to obtain food) and appeared impervious to chemical cues indicating risk. Exposing captive-reared individuals to both semi-natural foraging opportunities and predator-recognition training before their release is recommended.