PUB - Publikationen an der Universität Bielefeld

Sexual imprinting occurs in two stages, an acquisition phase when the birds learn about their social environment, and a consolidation process where the acquired information is linked to sexual behaviour and stabilized. Some of the factors that may influence acquisition and consolidation, respectively. were examined. Zebra finch, Taeniopygia guttata, males were reared by Bengalese finch, Lonchura striata, foster parents until 40 days of age, then isolated for 60 days, and exposed to a zebra finch female for 1 h at day 100. Thereafter, the birds were isolated for 3 days and then exposed to a Bengalese finch female for another 1 h. In subsequent preference tests, the preference scores of the birds were correlated with how much they were fed by their foster parents. The influence of the first exposure to a zebra finch female correlated positively with the level of arousal of the experimental males, as indicated by measurements of displacement activities and corticosterone levels. When first exposed to a female as adults, the experimental males could learn features of a potential sexual partner and, simultaneously, the acquired preference was consolidated. Consolidation, however, was independent of the appearance of the female: after having a 24-h access to a nestbox on day 99, the experimental males developed an exclusive preference for Bengalese finches. These results confirm that acquisition and consolidation are different processes which can be separated at least by the appropriate experimental design.