Wednesday, May 2, 2012

Mimicking Blue Jays and Killer Cardinals

Protecting her nest with borrowed sounds
A number of songbirds have already begun nesting around the area. They are mostly the year-round residents like Chickadee, Bluebird and Cardinal. I’ve also seen Crows and Jays involved with their nesting activities. Yesterday in the woods, I thought for a minute that I heard the long whistled call of a Broad-winged Hawk, but it turned out to be a Blue Jay that was only mimicking the call of the hawk. This is standard behavior with Jays. In this case, the bird was giving the hawk’s call in order to suppress a potential predator’s interest in her nest. Of course, with me it had the opposite effect; when I first heard the call, I began scanning around for a Broad-winged Hawk. It was only then that I spied the Jay and her nearby nest. Of course, if I had been a Red Squirrel, the call of the "hawk" may have been enough to send me running off in the other direction.
A Broad-winged Hawk, freshly back from the south
The fact that the Jay is using that call suggests that the Broad-winged Hawk breeds nearby. And indeed, the woods where I was walking is a known breeding ground for the Broad-winged Hawk. The Jays most often mimic the hawk species that they share habitat with, and over the years, I’ve noticed a change in the repertoire of our resident Blue Jays. Decades ago, many Blue Jays employed the shrieking call of the Red-shouldered Hawk in order to protect their nest areas or to clear out the competition at the local bird feeders. However, as Red-shouldered Hawks became scarcer in our region, the number of Jays using their calls also began falling off. Now it’s the more whistled shriek of the Red-tailed Hawk that is most commonly given by our Jays. And as the population of accipiter hawks like the Cooper’s Hawk and the Sharp-shinned Hawk recover in our region, more Jays are deploying their cackle calls as well.
Blue Jay sitting on her nest in a tangle of vines
Jays aren’t alone in mimicking hawks. In downtown Utica, which is the domain of the Peregrine Falcons, there was a European Starling that did a fairly credible impression of a Peregrine’s call. The call was actually good enough to cause me look up and see if there was a falcon nearby. Why the starling was mimicking the hawk was unclear; but that species tends to mimic a wide variety of sounds that occur in its environment –sirens, vehicles, other birds and even human voices. Often they are all mixed together with clicks and sputters in an eccentric jumble of noise. And believe it or not, I mean that in a good way!
The male Cardinal looking at his still undefeated foe

Lately, at the entrance to the Nature Preserve, where I park my car, a male Cardinal has been getting extremely territorial. In fact, he has been trying to conquer every reflection of himself that he finds in my car’s windows and mirrors. He’s convinced that every time my car shows up on the scene, his evil twin also arrives to muscle in on what’s his. Obviously, a reflection is a difficult rival to defeat –no matter how hard you pound away at him, he’ll always come back to spar. This kind of behavior is relatively common with Cardinals and with several other songbird species as well.
Occasionally people will call be for advice on how to deal with birds that spar with the windows on their homes. They try hanging strips of aluminum foil or pie pans in front of their windows; they try balloons and plastic hawks. I imagine the house looks jolly well interesting with all that stuff around the windows  –and of course, with a Cardinal still battering against whatever piece of window has been left unobstructed. That behavior is difficult to dissuade. I usually tell people to just wait the bird out. After all the nesting season isn’t that long. And at least it’s a really beautiful bird that’s terrorizing your house!
We had a Baltimore Oriole once that also had a problem with his reflection showing up in any vehicle’s side view mirror. The problem was that whenever he fought his “double” he had the unfortunate habit of relieving himself on the side of the car. It became obvious which cars had spent time in our drive way, because they’d all have the characteristic splash of “whitewash” right below their side mirrors. 

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