The struggle to raise young is difficult for wild animals, especially for birds of prey. For raptors, it is not uncommon for the youngest chick in a brood to die. In fact, a study of American Kestrels in Saskatchewan showed that the youngest bird survives to fledge in only roughly 68% of broods. Many have noticed that the youngest member of the brood in the KestrelCam box died last evening and was then eaten by its siblings. Although we hate to lose a chick, we realize that this is natural for wild animals and that raptors in particular have evolved this behavior to survive in a rough world. Last year, the youngest of five chicks also died in this nest box.
We’ve gotten several questions regarding how the chick died. Some have suggested that perhaps it was siblicide – the killing of one chick by another. Although siblicide is common for many raptor species, it is less common in falcons. Further, a review of the footage of the feeding event didn’t reveal a struggle before the death of the chick. Others suggested that perhaps the chick was a victim of brood reduction due to a lack of food. Brood reduction is when a parent selectively feeds the largest members of a brood when food is in short supply. It is certainly possible that the youngest chick starved, although we’ll probably never know for sure how the chick died.
Many questions also regarded the chicks feeding on their dead sibling. Although it can be hard for humans to imagine, cannibalism occurs among wild animals, including raptors. The study of American Kestrels in Saskatchewan suggested that dead chicks were eaten by their parents and siblings more often when food was in short supply. One of the things we all love about the KestrelCam is that it shows us aspects of nature that we rarely get to see. It shows us the great amount of work that the parents put into raising their offspring. Last night we saw just how hard the struggle to survive is for wild kestrels.