This Turkey Tuesday is about nest predation and how it’s studied. Many things eat turkey eggs, ranging from mammals, to snakes, to birds. Studying nest predation is difficult, because monitoring lots of nests without disturbing incubating hens is impossible. So, researchers often radio-mark hens and monitor their nests – after the hen leaves the nest they locate it to determine nest fate. In this 1st picture, the eggs are scattered about the nest site and have been eaten by a mammal – but beyond that, it’s hard to know what happened. So, researchers will sometimes use artificial nests to make inferences about nest predation – these nests are placed in spots where one would think a turkey would nest and a camera takes pictures or video of what visits the nest. But are artificial nests a good proxy for understanding actual nest predation? Well consider this. First, most critters identified as nest predators in artificial nest studies, such as raccoons, foxes, feral pigs, opossums, and crows, do not see hens as prey – and hens actively defend their nest against predators if they don’t perceive them as a threat to themselves. We’ve likely all seen the videos floating around social media of incubating hens attacking raccoons, snakes, and other predators. This 2nd picture shows a Gould’s hen sitting while a gray fox sniffs the area beside the nest! Second, consider that snakes are rarely ever noted as predators of artificial nests – yet are an important nest predator of actual turkey nests. Third, the hen sitting on the nest puts scent into the environment, which serves to attract some predators – many of which are after the hen and may or may not eat the eggs. Hens that are attacked may leave the nest site and not return, and sometimes their eggs are still intact several days later – the predator didn’t consume the eggs. The take home is, nest predation is a tough topic for researchers to tackle – understanding it is more complex than seeing what eats turkey eggs, because hens are adapted to protect their nests. The presence of the hen matters.
