Similar parental care in a generalist raptor: the case of Chimango caracara (Milvago chimango) in a suburban environment

GALLEGO, DIEGO; LARREA, MIKEL; AZPILLAGA, MAIALEN; ACELAY, IBAI; ARZAK, MAGGI; SOLARO, CLAUDINA; SARASOLA, JOSÉ HERNÁN

Congreso; 2018 Annual Meeting of the Raptor Research Foundation; 2018

The study of parental care in raptors is particularly important, since it can have strong implications for their ecology and reproductive success. Chimango caracara (Milvago chimango) is the most abundant and common raptor in Argentina, nesting in a wide variety of environments, including urbanized areas. However, there are no studies describing parental care behavior of this raptor. We performed focal observations (315 hr) in a colony of 74 nests of Chimango in a suburban habitat located in the center of Argentina, examining the division of labor between both sexes and the effects of these behaviors on their reproductive parameters (nest success and productivity). We measured incubation time during egg stage, and feeding rate (number of prey contributions per hour) and cover time (?incubation? after hatching) during chick stage. Incubation time was not significantly affected by the sex of the parent or by the number of eggs in the nest. Besides, there was no significant difference in cover time or feeding rate between males and females; yet, cover time decreased with the age of chicks, possibly suggesting that parents adjust their covering behavior to the ability of chicks to thermoregulate. Variation in the reproductive parameters of Chimangos was not explained by any of these variables. On the one hand, our findings suggest a similar (and symmetrical) parental investment of both sexes in the reproductive stage, being it independent of the number of eggs/chicks in the nest. On the other hand, results evoke the importance of other external factors (not covered by this research) for the success and productivity of nests, such as physical condition or anthropic disturbance, to name a few. Incorporating such sources of variation into models will help at understanding parental care in this generalist raptor.