Q: Good or bad: I maintain a heated birdbath in winter, and have read that birds shouldn’t take baths in it on really cold days. My feeling is that birds have enough sense not to immerse themselves in water when they could freeze to death, but what do you think?
A: This is a somewhat controversial topic among those who maintain heated birdbaths in winter. Some would agree with you, feeling that birds will use good sense in choosing whether to bathe on really cold days. But many others, myself included, regard heated birdbaths on days when it’s below about 20 degrees as dangerous to birds. They regard liquid water as a signal that it’s warm enough to have a bath. But we deceive them when we provide open water in otherwise icy conditions, and there are reports of birds bathing in the brutal cold, then succumbing to exposure as their feathers ice up. On the coldest days, I advise placing a board, tree branch or other barrier across the birdbath basin to block much of the surface, so birds can drink but not bathe.
Owls lease, not buy
Q: What kind of nest does a great horned owl build?
A: Good question, and you may be surprised to learn that great horned owls (and most other owl species) don’t build nests at all. Instead, they adopt an old nest built by a hawk or squirrel, or use a broken area in a tree to raise their family. (This has always intrigued me, and I’ve wondered why owls aren’t nest builders, but I’ve never found an answer, even after asking the experts. It seems limiting to have to rely on other species, or windstorm damage to trees, to create nesting sites.) To locate great horned owl nests, check the tree canopy for large structures or in broken trunks, for those characteristic “ears” sticking up. And listen for owls hooting to each other at night to guide the way. Which owls do build nests? In our region, both the snowy owl and short-eared owl pull together vegetation to make a bowl for their eggs on the ground.
Hawks vs. juncos
Q: Cooper’s hawks fly into my backyard and seem to snag juncos more often than other birds, like house sparrows. Do you think our city birds are more alert to hawks than juncos?
A: Cooper’s hawks prey on smaller birds, as you’ve noticed, and several studies indicate that European starlings, a nonnative species, make up a significant portion of their diet. In my own neighborhood, I’ve observed Cooper’s hawks snatching cardinals, flickers, chickadees and blue jays, and signs (piles of feathers in the backyard) indicating that they catch juncos, woodpeckers and robins, as well. Hawks have greater success with young birds that haven’t yet fully developed their survival skills. Juncos have another handicap in that they’re migrants, visiting our area only in winter, so early in the season they may lack a sense of where to hide for safety. Sparrows seem to be more wary and often feed in large groups, so can warn each other if danger approaches.
Strange speckled bird
Q: I’m confused about a bird that’s been frequenting our backyard. It looks like a blackbird, in some ways, but I can’t find it in my bird guide. What do you think?
A: The bird in the photo you sent confuses many people because it looks so different at different times of the year. It’s a European starling in its winter coat, with pale tips on all its outer feathers. This gives starlings a speckled look and if you’re not used to seeing starlings in winter, this can be startling. By spring, those pale tips will have worn off, and starlings will again look like the iridescent black birds we’re used to seeing.
