Watching birds at the feeder outside the kitchen window is still our favorite pastime and continues to yield more information as the years go by. This spring we watched a drama unfold that I would not have believed if I had only read it somewhere. Our kitchen window faces out on a patch of woodland, and we can see, especially with binoculars, a number of nesting sites in the trees beyond the bird feeder. One tree trunk cavity, about 20 feet high in an oak tree, has always been home to a pair of nuthatches. Last winter, two red squirrels took over the apartment and I was sure that would be the end of the nuthatches at that location. Even up into spring, we could watch them carrying what looked like nuts or acorns into their hole while I wrathfully muttered obscenities in their general direction.
The drama that then unfolded started in a tree close by. Red bellied woodpeckers took over a hole in that tree and ferociously guarded it when fox squirrels (of which we have a small army) approached. I always thought the squirrels won these encounters but not so. At the same time, a pair of nuthatches began to hop around the hole that the red squirrels had taken over. A week later, they were entering the hole and emerging with tufts of leaves and other debris in their beaks, which they would stick into the bark of the tree trunk above and below the hole. I have no idea what they were doing, but soon the squirrels were gone and the nuthatches back in business.
We searched the bird books and found only this passage about white-breasted nuthatches in A Field Guide to Birds’ Nests: “Nesting in large cavities in tall trees puts this species in competition with squirrels. Strange behavior called ‘bill sweeping’ …. may be a territorial defense mechanism. Both [male and female] engage in prolonged (several minutes) sweeping of bill in a wide arch inside and outside cavity, generally with insect held in bill. Unproven theory is that crushed insects may repel squirrels…”
I have a hard time believing that, but I would have thought that nuthatch mommas would not be able to chase away squirrels even if armed with pink pistols. Whatever is happening, it is more evidence that nature has ways to maintain the variety of species. Nuthatches can run off squirrels. We have also noticed that bluebirds nesting in a cavity high up in a hickory tree nearby defend it successfully from starlings and squirrels. My books don’t mention that detail either. Does anybody know what’s going on here?
At the feeder, we have observed that some birds are more polite than others. Blue jays are very rude to the other birds but when the red bellied and redheaded woodpeckers drop in for a bite or two, they send the brazen jays flying. Cardinals seem to be the only larger species to allow the small birds to alight and eat right beside them. Cardinal males are very gallant, often taking a seed in their beaks and feeding it to their mates. The smaller downy and hairy woodpeckers are almost as feisty as the red bellies. Chickadees and tufted titmice are the most timid but quicker than lightning so they get in and get out of the feeder with a seed in their beaks before the larger birds can stop them.
The way birds (and all wildlife) adapt to new situations always amazes me. The lid to our hummingbird feeder of sugar water is cuplike on top, so a bit of rainwater gathers there. The goldfinches have learned this and after eating awhile, fly up on the hummingbird feeder and get a drink of water.
Being a pessimist, I am forever fearful that the number and variety of birds at the feeder is diminishing, only to be pleasantly surprised in another year. In the past, a rose-breasted grosbeak would occasionally come to the feeder. Then none came until this year when three pairs were frequent guests. Even more dramatic, only in the last year have we ever had big pileated woodpeckers in our tree grove. They don’t come to the feeder to be sure, but drum away in the woods. I don’t think the world is about to end just yet.