BRAINERD — In 1822 famous ornithologist John James Audubon shot a duck he could not identify.
"In form and proportions this bird is very nearly allied to the Mallard," wrote Audubon of the odd duck. "It may possibly be an accidental variety, or a hybrid between that bird and some other species, perhaps the Gadwall, to which also it bears a great resemblance." Audubon named the bird Brewer's Duck, after his friend Thomas M. Brewer.
In just a few short weeks, waterfowl will begin to migrate in force into Minnesota. A few species, such as Canada geese, mallards, goldeneyes and mergansers, are already trickling in, taking advantage of open water in some swift-moving rivers. With luck -- and a discerning eye -- a person might, like Audubon, identify a hybrid among those birds.
Most biologists agree that hybridization is more common among waterfowl than any other bird species. The mallard, for instance, has been known to breed with about 40 other species of waterfowl worldwide. Wood ducks have crossbred with at least 20 other duck species.
I've been fortunate over the years to not only spot several waterfowl hybrids but also have captured images of some odd ducks.
One sunny spring morning I was photographing waterfowl from the tight confines of a blind I had built next to a small pond on my property near Brainerd. During a lull in the action I took a moment to stretch my stiff neck by rocking my head from side to side. When I again peered through a port in my blind I spotted what I immediately recognized as an unusual duck; a male blue-winged teal/northern shoveler hybrid.
The bird was swimming past my blind at close range and in perfect light. I shot several images before it swam from view.
It's interesting that waterfowl hybrids usually possess distinct characteristics of both progenitors. The blue-winged teal/shoveler hybrid I photographed had the spoon-shaped bill and cinnamon-colored sides of a shoveler. It also displayed the telltale white crescent near the eye and spotted breast unique to blue-winged teal drakes. In other words, hybrids do not appear as if you placed two species in a blender and flipped the switch; more like you chose distinct parts of each bird and copied and pasted those pieces to build the hybrid.
Another example of this "piece work" is the mallard/pintail hybrid. I photographed a beautiful example of a classic hybrid a few years ago while in South Dakota. The bird showed the blue bill, pointed tail and long narrow wings of a pintail, but it also sported the green head, white neck ring and brown chest of a mallard.
Hybrids of closely related duck species are often fertile, but those less closely related are not. Example: Mallard/black duck hybrids are often fertile. It's fascinating to me each time I see a mallard hybridized with another species. The bird apparently "think" they are mallards because they associate with mallards, rather than with the other species.
Over the years I have photographed various hybrid waterfowl such as mallard/black duck, mallard/pintail, mallard/shoveler and shoveler/blue-winged teal. Each image is special and resides in a prominent spot in my photo files and my memory.
When a hunter bags a rare hybrid duck, the unique fowl often occupies a prime location on a den wall, offering years of conversation fodder.
Keep your mind open to the variables in nature and you may spot a rare hybrid, too.
Bill Marchel, an outdoors columnist and photographer, lives near Brainerd.