In Kenya, death usually comes to large herbivores in the night hours. That's not so great for gazelles, but the evening expirations offer scavengers a ready-made morning feast. Given that the greatest pickings are available in the morning, biologist Corinne Kendall wondered, if, when it comes to vultures, the early bird gets the carcass.
In Kenya's Masai Mara National Reserve, three vulture species compete for recently deceased beasts: the white-backed vulture, the lappet-faced vulture, and Rüppell's vulture. Kendall, a biologist at the North Carolina Zoo, laid out small goat carcasses at various locations to observe which vulture came to a carcass, when they came, and how long they stayed.
White-backed vulture descended on a carcass like a pack of wolves, leisurely dining until they'd eaten their fill. Rüppell's vultures also proved to be morning birds, but travel in smaller groups. Without numbers on their side, they couldn't compete with white-backed vultures that had already claimed the carcass, Kendall found. Lappet-faced vultures, meanwhile, approached one at a time in the afternoon, as the white-backed vultures began to disperse. So why didn't Rüppell's vultures opt for a late brunch, too? Kendall thinks it's because they nest on cliffs, and can't leave their young unattended in the glaring midday sun. White-backed and lappet-faced vultures, on the other hand, likely can leave their offspring alone for longer periods because they nest in trees.
For vultures, it seems, the early bird does get the worm, er carcass—so long as he brings his buddies.
This story has been edited to clarify that Rüppell's vultures scavenge in smaller groups and to indicate Corinne Kendall's current affiliation with the North Carolina Zoo.