HABITUATION OF A PREDATORY RESPONSE IN THE STICKLEBACK (GASTEROSTEUS-ACULEATUS)

Sticklebacks presented with a clear glass tube filled with live brine shrimp will initially attempt to capture them; however, the response w anes within minutes. In the case of females, the rate of initial respo nse is enhanced and the rate of waning is influenced by the state of t he female (gravid females are more responsive) and by the density of t he prey (greater density results in greater responsiveness). The preda tory-response habituation differs from habituation of territorial aggr ession and courtship in that the pre-decremental, incremental process is absent. In common with habituation of territorial aggression but no t with courtship, there is little short-term recovery of the response. The differences are consistent with different functional requirements for an experience-based inhibitory mechanism involved in the modulati on of stickleback behaviour.