校园行知客Birds pay gruesome reward to alligator bodyguardsBirds pay gruesome reward to alligator bodyguards It helps to have an alligator for a neighbor—that is, if you’re a nesting bird in the Everglades. The toothy reptiles scare off potential egg thieves like raccoons and opossums, so birds such as herons and egrets—which nest in colonies of hundreds of individuals—tend to choose nesting sites in alligator territory. But new research shows that the gators get something a bit more gruesome in return: food in the form of surplus chicks that fall from the nests. The new study, published today in PLOS ONE, shows that alligators living near wading bird colonies are fatter than those with no birds nearby, even after controlling for environmental factors like water depth. Wading birds typically lay more eggs than they can raise, and they eventually get rid of extra chicks by pushing them out of the nest. This rain of protein could be a windfall for alligators. So could the birds’ droppings, which may attract alligator prey. Alligator relatives and wading birds live together in many other wetlands, so the researchers say this grisly arrangement could be important worldwide.