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

Abstract

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.

Variation in Bird Eggs—Does Female Factor, Season, and Laying Order Impact the Egg Size, Pigmentation, and Eggshell Thickness of the Eggs of Capercaillie?

“…The whole clutch is numbered usually 6–8 eggs that are laid every second day. This makes the laying period 12–16 days [ 38 ]. We cannot exclude that at described shape change, environmental conditions, such as temperature, have a greater influence than laying order.…”

“…In captivity, when more than one female is kept together, egg appearance may be an indicator the nest is used by more than one female. This happens often and may lead to aggression and lowering breeding success [ 38 ]. Nests that contain eggs of different appearances should be observed more closely due to the greater probability of abandoning the nest or egg destroying.…”

Low frequencies in the display vocalization of the Western Capercaillie (Tetrao urogallus)

“…After approaching to calling males at close distance, females could make the choice decisions on the base of the ques reflecting the quality of male based on low-frequency components. It has been found that females in captivity preferred to mate with males with a longer calling activity (Rosenberger et al, 2020). The final female choice at a closer distance could reflect the tradeoff between finding a high-quality mate and predation risk including energetic costs from evaluation of several males on lek.…”