Harman V.S. Peeke

Abstract

1) Male three-spined sticklebacks which were clearly in the sexual phase of their reproductive cycle, were presented with aggression eliciting stimuli for a period of fifteen minutes each day for ten days. One group was stimulated with a live, nuptially colored male stickleback in a clear plastic tube each day. Another group was presented with a wooden model of a male stickleback each day. The third group received no aggression eliciting stimulation. Both groups which received stimuli showed a decrement in responding to the stimuli over the ten days; the more dramatic decrement was found with the group presented with a live stimulus since this stimulus elicited the greatest aggression initially. 2) Aggressive responses did not all wane at the same rate, but rather one, charges at the stimulus, dropped out first, followed by bites. Orientations toward the stimulus decreased over the ten days but never reached a low level. 3) All three groups were presented with a gravid female stimulus for five minutes each day. The group presented with a model of a male stickleback and the group presented with no male stimulus both showed no change in the level of sexual response directed toward the female stimulus. The group presented with the live male stimulus demonstrated an increasing number of sexual responses directed at the gravid female.

Lance Morgan and Harman Peeke

Abstract

Threespine sticklebacks (Gasterosteus aculeatus) from marine, estuarine and upstream fresh water were collected from two coastal watersheds in northern California. Laboratory tests of response to behavioral stimuli associated with aggression, courtship and feeding show interpopulation variation. Behavioral responses of populations from the same habitat type were similar, and individuals from up-stream habitats were generally more responsive to stimuli than individuals from the estuarine environments, which in turn were more responsive than marine fish. Different predators and predation pressures are discussed as one possible factor in the evolution of these behavioral variations.

Harman V.S. Peeke

Abstract

Sticklebacks presented with a clear glass tube filled with live brine shrimp will initially attempt to capture them; however, the response wanes within minutes. In the case of females, the rate of initial response is enhanced and the rate of waning is influenced by the state of the female (gravid females are more responsive) and by the density of the prey (greater density results in greater responsiveness). The predatory-response habituation differs from habituation of territorial aggression and courtship in that the pre-decremental, incremental process is absent. In common with habituation of territorial aggression but not 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 modulation of stickleback behaviour.

Harman V.S. Peeke and Shirley C. Peeke

Abstract

Mature male Siamese fighting fish (Betta splendens) were presented with a conspecific male confined in a clear plastic tube for either 15 minutes per day for 20 days (group E 15) or 60 minutes per day for 5 days (group E 60). A third group was presented with this aggression eliciting conspecific male stimulus for 15 minutes on days 1 and 2 and again on days 19 and 20. This group (group C 15) was designed to control for post-stimulation waning of aggressive behaviors independent of constant stimulation and also to control for response decrement as a simple function of time. Two components of the aggressive display and frequency of biting were recorded. It was found that with groups E 15 and E 60 all aggressive behaviors habituated. In general, habituation was more rapid with the short stimulation periods than with the longer ones, although qualitative differences were also found and described. Comparisons of groups E 15 and C 15 showed that repeated daily exposures to the aggression eliciting stimulus were necessary to obtain habituation and that two days of 15 minute stimulation followed by 16 days of no stimulation did not result in response decrement on any of the measures recorded.

Michael H. Figler and Harman V.S. Peeke

Abstract

A model female stickleback presented to a territorial male with a nest usually results in the male courting the model with a series of zigzag movements followed by a leading to the nest entrance. Following such a display, a live gravid female might follow, enter the nest, spawn and leave permitting the male to fertilize the eggs. Frequently, however, the female is not ready to spawn, and the male continues to court until, at some point, he ceases courting that female at least for a short period of time and directs his attention to another female. We propose that mechanisms involved in the modulation of this behavior may include habituation and sensitization in a way that is analogous to that apparently involved in territorial aggression and predation. This study demonstrates that habituation and sensitization do influence the behavioral decrement and reinstatement respectively of male courtship of a female model, and it may be that the stickleback uses habituation as one means of curtailing courtship towards unresponsive females, thus conserving energy and permitting redeployment of attention to other, possibly more responsive, females.