Laura Erickson's For the Birds

This summer when I was teaching my Elderhostel class on Burntside Lake near Ely, I learned a valuable lesson: to attract a large crowd to a beach in a hurry, all you need is a dead duck. One little kid spotted it where it had been washed ashore and shouted, and within a minute or two, a mass of people surrounded the pitiful thing, all clamoring to know two things–what kind of duck was it, and how did it die?

It was a sodden gray mess, but duck wings are surprisingly easy to identify–this was an adult female Common Goldeneye. Goldeneyes nest in tree cavities and Wood Duck houses, and are fairly common in the Boundary Waters area much of the year. This was June, which meant she probably had had eggs or ducklings that were doomed with her death.

It’s not always easy to figure out how dead birds came to arrive at their dead condition, but this one had clearly bled to death through a gaping cone-shaped wound, over three inches deep, in her lower breast muscle. She had apparently been stabbed from beneath as she swam. Our simple autopsy turned into a case study in forensic pathology as we noted the hard evidence of that stab wound–the signature of the murderer. The wound was exactly the size and shape of the beak of an adult Common Loon. Yes, our poor little duck had been done in by a loon.

Common Loons eat some aquatic insects and other crustaceans, but mostly they eat fish. They never eat ducks or other birds. But it takes a full ton of fish to maintain a pair of loons and their two chicks over a summer–they can’t afford to share their lake with anyone who might cut into their food supply, especially, a fish-eating duck and her dozen or so babies.

Usually the mere sight of a territorial loon is enough to keep any duck at bay, and ducks are usually quick enough that if a loon does charge, they can spring out of the water and get away fast. A cursory examination of this duck showed why she didn’t escape–one of her feet was deformed, with crooked toes and incomplete webbing between them. It wasn’t a severe handicap under most situations–she had managed just fine for at least one full year–but that bad good slowed her down the one time a fast getaway was critical.

There are many records of loons attacking, and occasionally killing, ducks and other water birds, but there’s also a record of a pair of Arctic Loons adopting several eider ducklings and raising them along with their own two healthy chicks. Ducklings are perfectly capable of feeding themselves, but these babies accepted food as well as protection from their loony parents. A human judge might convict an attack loon of second-degree murder, or commend a pair of loons for compassionate caring for orphans and award them custody. But Nature has no judge or jury. Nature makes no distinction between good guys and bad guys–she acknowledges all creatures, great and small, just as long as they survive. Case Closed.