This is pretty cool. Many birds are pretty obsessive about caring for offspring, to the point where it’s often easy to trick them into caring for other creatures — when they’re in brood mode, most of them will stuff food into anything that looks like an open beak. Here in Minnesota, a bald eagle couple is rearing triplets. (Twins is more common, but triplets do happen. Usually only one will survive to adulthood, though, in no small part because the chicks will fight their nestmates to eliminate the competition.) The chicks are just a few weeks old, and about a week ago, the parents brought a female mallard to the nest, killed her, and served her up to the chicks. She was egg laden, and a duck egg popped out. Usually, eggs of prey will be eaten, but these eagles just had eggs of their own hatch and they’re still very much in brood mode; they rolled that duck egg into the middle of the nest and have been sitting on it, along with their own chicks.
What will become of this duck egg? Will the eagles eventually decide it is taking too long to hatch and ditch it as a dud? Will the eaglets eat it? Will it hatch, and if so, how long will the duckling survive? Will it starve? Try to waddle off and fall out of the nest? (Eaglets stay in the nest for months; ducklings are expected to walk away the day they hatch and never return, trailing their momma around.) I’ve tuned into the live webcam a few times and have not been able to catch a glimpse of the egg — but the adult eagles are definitely still brooding. Tune in and see what happens!