Female-Male and Female-Female Social Interactions of Captive Kept Capercaillie (Tetrao Urogallus) and Its Consequences in Planning Breeding Programs.

Abstract

Simple SummaryThe Capercaillie is one of the most endangered bird species in many European countries. To prevent further population decline, breeding centers where birds are bred and later released into the wild were established. However, in many Capercaillie breeding stations, reproductive success is limited due to low fertility and problems with incubation behavior by females. Reasons for these problems are usually multidimensional, including misunderstanding Capercaillie behavior in the breeding environment. Research was conducted in Capercaillie breeding centers where birds were monitored 24 h/day by cameras. We observed that females preferred to mate with males with a longer tooting activity, but when males became too insistent and started to chase the females, they avoided contact. Even when the density of females was only one bird per 132 m2, nesting site competition occurred. In 67% of the nests, female intruder’s presence could be observed. Interactions between females were mainly antagonistic, and while none of the birds were harmed, this caused egg damage and nest abandonment. Nesting site competition in captive Capercaillie is high and may lead to antagonistic interaction between females, consequently lowering breeding success. Our research showed also that mate preference of males by females could be predicted by observing the male’s tooting activity.Capercaillie behavior, both in the wild and in captivity, is poorly known due to this species’ secretive way of life. Female-male and female–female social organization and interactions are especially poorly documented. The research was conducted in Capercaillie Breeding Center in Wisła Forestry District where a breeding flock is kept throughout the year. Thanks to video monitoring, we were able to observe mate choice, and then later, female–female interactions during laying and incubation period. Male individual variation in tooting latency and duration were recorded. Females’ interest in males was related to males’ tooting activity, but when males became too insistent and started to chase the females, the females avoided contact with them. There was a significant relationship between calendar date and when tooting starts, and between the tooting duration the female spent with a male. Two incidents of female-male aggression caused by competition for food were observed. Female intruder presence and competition for nesting place was observed in 66.67% nests. Most female–female interactions were limited to threat posturing, but fights and attempts to push out the intruder from the nest occurred as well. Such interactions may lead to nest abandonment and egg destruction, lowering the breeding success.