The northern cardinal needs no introduction, because the species routinely introduces itself to everyone around it.
Nothing says “look at me” like the namesake bright red plumage and bold crest atop the head.
The loud and clear whistles of the cardinal’s songs grab attention no matter how many other birds are singing. And the female cardinal is one of the few North American songbirds to sing out, too, often while sitting on its nest.
This time of year, mere introductions aren’t enough for cardinals. They’re ready to force themselves upon other birds, particularly other cardinals, in asserting their claim to choice territory to raise a family.
Often people become the targets of cardinal aggression — their windows, anyway.
Depending on how a window is facing and light conditions, the glass makes a pretty good mirror – good enough to fool a cardinal into thinking its reflection is another cardinal.
Naturally, the cardinal won’t stand for a competing cardinal brazenly trying to grab its territory, so it flies at the bird in the window reflection repeatedly, trying to bully it and make it go away.
Cardinals seldom back down, and the reflection isn’t going to back down, so this kind of crashing against the window can keep up for weeks during spring breeding season. The Cornell Laboratory of Ornithology has a report of the jousting continuing for six months in one case.
This bothers people quite a bit, in small part for the noise and chance of damage to the window, and in large part because the idea of a favorite bird possibly self-destructing against their house is tough to bear.
John Oesterling, of Upper Deerfield Township, asked for advice on dealing with such a female cardinal. The bird crashed the front window for days, regardless of the position of the blinds and a stepladder with a scarecrow attached outside.
After telling John the only sure thing was covering the window enough to stop the reflected image, he and his son covered the windows on the outside with cardboard and black plastic.
“Eureka! The female cardinal is not crashing into my windows anymore,” he said. “I will leave it on the windows through nesting season. One more question. How long does the nesting season last?”
Nesting season can be long, with the cardinals raising two or even three broods, but luckily you shouldn’t have to wait until that’s over.
Once we’re into mid-June to early July, your cardinal’s raging spring hormones should have settled down and let her focus on the more important task of caring for kids than facing down a faux competitor.
And on the bright side, you’ll have even more of America’s most sought after backyard bird, the one that motivates many to first pick up a pair of binoculars, or even upgrade their feeder seed to lure them from a neighbor’s yard.