Rock Doc

During the winter I like to feed the birds. I have a very simple arrangement for this: pouring a mix of seeds on a flat railing outside my dining room window. I regularly attract several species of small birds to the seed.

Buster Brown, my mutt from the pound, has a role to play in the bird feeding. It’s his job to make the squirrels wary of coming up to the railing and stealing the seed. Buster has a dog-door, so he always has access to the area in question, and although he has never in his life caught a squirrel, he is glad to give chase. (Buster agrees with my mother that squirrels are really just rats with furry tails.)

Buster and I are really a team when it comes to squirrels. When I see one out the window on the railing, I call “Buster Brown, squirrel, squirrel!” My faithful dog then charges out the dog-door, putting him about 4 feet from the rodent. The chase is on, often going across the yard to where the squirrel can climb a tree where it scolds Buster to its heart’s content.

But am I really doing a favor to the birds by feeding them each winter? That question was the subject of a recent blog post by Joe Smith published by The Nature Conservancy. It turns out there’s a bit of scientific research on the matter.

Common sense suggests feeding birds during the tough, cold months helps them survive the most challenging of seasons. Our feathered friends need food energy to keep themselves warm, and winter limits the availability of food. Some scientific studies do agree with common sense: more birds survive the winter when they are fed than otherwise.

The Nature Conservancy blog post referenced a study in the upper Midwest of black-capped chickadees. Those fed by people had a higher survival rate over the winter (69 percent) versus those that weren’t fed (only 37 percent survived).

But for some birds in given locales, feeding may be, paradoxically, detrimental. Researchers in Great Britain discovered that certain fed birds laid fewer eggs the following spring and summer than did unfed birds. And the fledglings of the fed birds were less likely to survive than the offspring of unfed birds.

It’s not abundantly clear why fed birds would have less success with their offspring than unfed ones. It may be that store-bought bird seed isn’t really a balanced diet for birds compared to what Mother Nature provides, and there may be other factors, too.

Still, many studies suggest feeding the birds helps them out in tough times. That’s why, with the help of Buster to fend off the squirrels, I’ll continue to feed birds in my backyard.

Dr. E. Kirsten Peters, a native of the rural Northwest, was trained as a geologist at Princeton and Harvard. This column is a service of the College of Agricultural, Human, and Natural Resource Sciences at Washington State University.