Pellets from Tuas: 8. Black-shouldered Kite feeding chicks

The ground below the nest of the Black-shouldered Kites (Elanus caeruleus) is often littered with carcases of mice and numerous pellets. The image above shows a headless mice found below the nest. An intact mouse was also found below the nest (below)

We believe they fell from the nest when brought in by an adult. We had observed that within minutes on the ground the dead mice would be covered with ants. Thus returning it to the nest would introduce ants and pathogens. Another reason these fallen mice were not retrieved can be that there were no shortage of mice in the area.

Young chicks were fed pieces of meat torn off from the prey by the adult. Older chicks were fed entrails (above), skin, bony body parts.

The above image shows an adult offering a mouse head to a chick. It proved too big for the chick to manipulate and fell into the nest. It is most probable that any head would first be broken up and the pieces fed to the chicks. This has been confirmed by pellet examination. Only jaw bones, loose molars, incisors and miscellaneous pieces of bones were found in all the pellets examined, never whole skulls.

The chicks regularly regurgitated pellets into the nest and the adults routinely picked them up for disposal away from the nest (above).

With four chicks in the nest there was no space for the adults. But there was always one adult perching nearby, keeping a watch on the chicks. Sometimes both adults went foraging nearby in case of attacks by crows or raptors. We estimate that at least half a dozen mice a day were needed to feed the hungry chicks. And whenever a mouse was brought to the nest all four would tear it apart to feed – always orderly and seldom, if at all, fighting for the parts.

Chan Yoke Meng & Melinda Chan
Singapore
April 2015