I have tried to make my two urban lots as welcoming to wildlife, particularly birds, as possible. Seeing the wild things nearby keeps me in touch with the natural world, even though I live in town. Nature appears, at least on the surface, entirely benevolent as I sit to write early this sunny spring morning. A bluebird, wrens and robins are singing and my feeders have already been visited by a variety of birds.
There’s a definite tension out there among my wild neighbors, though. Four robin nests have been attempted on nest platforms I added high under the eaves of my house. Even though well-protected from all the nasty weather, all have failed to fledge any young due to nest predation. The nests were unreachable by mammalian predators, but the blue jays and grackles that visit my feeders are also fond of bird’s eggs and young. I enjoy watching tiny, tame chipping sparrows feed on bird seed only a few feet away as I sit on the deck with a cup of coffee. I know that their odds of successfully raising young are slim, though, due to the presence of cowbirds, which parasitize nearly every nest they attempt. My human sense of fairness is offended when I see a pair of “chippies” feeding a young cowbird nearly twice their size. I know that little cowbird pushed the chipping sparrow eggs and/or young out of the nest so that it could benefit from all of its foster parent’s feeding attention. My beautiful cardinals and rose-breasted grosbeaks are likely to be victimized by the same cowbirds, too.
Cheerful little wrens have chosen a box on my yard fence. They sing beautifully and are great bug eaters in my garden. They can also be death for other cavity nesters like the bluebirds, who are building a nest in a box just outside my kitchen window. The male house wren fills every cavity he can in his small nesting territory with twigs. The female will select one of those twig filled cavities and build a small fiber cup nest in a corner of it. She and her mate will raise at least three broods of little wrens during the summer. The male is not above piercing the eggs of other cavity nesters, like bluebirds and chickadees, only to add his twig piles on top of their nests.
My male bluebird appears pretty protective of the nest box they have chosen. And that’s a good thing with a family of wrens nearby and the neighborhood house sparrows still wanting nest sites. House sparrows are particularly persistent in trying to take over and keep a nest box. I threw house sparrow nest material out of the three bluebird boxes on my lots nearly every day for three weeks before they backed off a little. If I missed even a couple of days, I’d often find eggs in their new nests, as well. The male bluebird was observed chasing a male house sparrow the other day, but the sparrows haven’t given up. They’re back in one of the empty bluebird boxes today and could still attack my bluebird nest. They’re known to break eggs and peck incubating female bluebirds to death.
One of the neighborhood house finches seemed particularly tame as I came out to fill a sunflower seed feeder a few weeks ago. I was able to approach within a few feet and noted that he had a disease that had caused his left eye to swell shut. He survived a couple of weeks, but was obviously losing strength. I was able to physically lift him out of the way to fill the feeder before one of the recent storms, but I haven’t seen him since.
A family of Cooper’s hawks have a nest only about 100 yards west of my house. I fear for my yard birds. Some will doubtlessly become food to feed the growing baby hawks. I thought I’d already lost the male bluebird last week when I found three bluebird wing feathers and some down feathers under a perch he often sang from. Perhaps the hawk took a bluebird, but “my bluebirds” are still here … at least today.
(Steve Lekwa is retired director of Story County Conservation.)