Laura Erickson's For the Birds

Leucistic Barred Owl

Sunday afternoon, while I was eagerly awaiting the Oscars, I got an email that completely diverted my attention from movies back to birds. Mike Furtman, the wonderful outdoor writer and photographer, was writing to tell me about a fascinating bird he’d had the day before in his Duluth backyard—a virtually all-white Barred Owl. His owl was so white that it was initially identified as a Snowy Owl, but was too small and had dark brown, rather than yellow, eyes. Mike’s immediate impulse, naturally, was to take photographs, and to alert the Hawk Ridge naturalist, Debbie Waters, who was there in a flash, with bander Dave Grossheusch not far behind. Mike already has photos of this bird on his website, along with an amazing collection of other owl photos he’s taken this year. It’s a great website to browse—he’s a talented photographer.

In Mike’s photos of the owl being held by Dave Grossheusch, you can see extremely faded, pale markings on the outstretched wings. Although the bird appears almost pure white from a distance, the eye color and the washed-out plumage make it not an albino, but what ornithologists call a leucistic bird. Leucism can be caused by genetics, when a bird is programmed to produce less melanin and other pigments, or can be caused by poor nutrition, when a bird’s diet doesn’t include necessary components for pigment production when it molts into new feathers. Just looking at a bird, it’s impossible to know why it’s leucisitic, but interesting, quite a few Great Gray Owls this year are showing abnormal plumage, too, some with large areas of pale feathers.

Birds that are albinos, partial albinos, or leucistic are fascinating to see. They’re often tricky to identify, though sometimes, particularly with sparrows and juncos, you can identify the bird by the company it keeps or, with robins and Red-winged Blackbirds, but the shape, size, and behavior. I’ve seen all-white robins, and robins that looked like a patchwork of normal colors and pure white. I’ve seen red-wings with white epaulets, or white-and-yellow epaulets, with otherwise perfect black plumage, and red-wings that had normally-colored red-and-yellow epaulets with the rest of their body pure white. I haven’t personally seen an albino hummingbird, but I’ve seen many photos of them. A true albino has both pure white feathers and a pink or red eye. Many birds identified as albinos are actually partial albinos, with pure white feathers but normal pigments in the eyes.

Feather pigments not only give feathers a particular appearance—they also add structural strength. Few birds are pure white—most very white species, including Whooping Cranes, Snow Geese, white pelicans, and most gulls, have black wingtips, the black pigment strengthening the part of the wing that gets the heaviest wear. White ducks and chickens were intentionally bred—the feathers not only make domesticated birds look nice for farmers, but the lack of pigment in feathers and skin also make the birds easier to pluck. True albinos don’t survive long in the wild—lacking all protective pigments, including those of the eyes, they’re likely to become blind rather quickly. Some species are pretty fussy about their mates looking precisely like their parents, but a great many birds accept a partial albino or a leucistic bird as a mate, as long as its behavior indicates it’s healthy and strong. Mike Furtman’s white Barred Owl has clearly made it through at least 9 months of life, and may be much older—age is hard to ascertain on a bird with abnormal plumage than one colored normally. With luck, even with its strangely lovely plumage, it will live to a ripe old age and give many other birders the joy and fun of seeing it. Meanwhile, you can get a link to Mike’s great photos by going to my webpage at www.lauraerickson.com and clicking on the transcript for today’s program.