The advantage of being a birder is that spring comes so much earlier. January wasn’t even over yet when chickadees began their territorial songs of “Hey, Sweetie.” Cardinals began crooning their mate-wooing song: “Chew, Chew, Chew.” And, right on cue, cardinals began disliking each other.

Every year, around the beginning of February, I begin to receive emails asking, “Why is a cardinal pecking at my window?” About half of the messages surmise that it is because the bird sees its reflection, and that is correct. Both male and female cardinals get territorially aggressive in spring, and the birds will treat their own mirror images as intruders.

During the early part of winter, cardinals get along just fine. It’s not unusual to see multiple cardinals hanging around a bird feeder. But as the days lengthen, the birds get testy with each other. Mating season is now underway as the cardinals pair up and establish territories.

Other birds attack their reflections, too. Tiny chickadees attack windows. Gargantuan turkeys attack shiny hubcaps. It has begun.

Ducks are pairing up. Over the last week, I watched male common goldeneyes cozying up to hens. Theirs is a unique mating dance. Males stretch their necks forward, bill low over the water, then snap their heads upward, with bills pointed skyward as they whistle a couple of call notes. Chicks dig it.

For the early part of winter, the two goldeneye genders don’t even associate much. It’s common to find males wintering farther north than females. But they are beginning to mingle now. It’s worth noting that much of this mating behavior is taking place in saltwater and tidal rivers. Pair bonds are formed far from their actual nesting grounds, up on the freshwater lakes and wetlands of the north woods.

Harlequin ducks nest even farther north, along the whitewater rivers of Canada. Compared to the romantic goldeneyes, these brightly colored waterfowl are downright belligerent. A few weeks ago, I watched two male harlequins relentlessly wooing a female, chasing her repeatedly. They dove and fed as a group, and then one of the males would begin a courtship display by paddling in her direction swiftly, nodding his head backward and forward.

Two years ago in early March, I was walking the path along Marginal Way in Ogunquit when I was astonished to watch a pair of harlequins actually copulating — something they can do on water. I assume this was more for practice than actual breeding, because they were still two months and a thousand miles away from any possible nesting site. Unlike the goldeneyes, harlequins start to form pair bonds very early, sometimes as early as October.

Harlequin ducks are declining in the east, and they are considered threatened. Maine has a small wintering population, and they are relatively easy to find along the rocky shoreline of York County. Larger groups flock around Isle au Haut, and you can join me for a chance to see them on March 31, when Island Heritage Trust takes over the Isle au Haut Ferry for a winter adventure. See:

Offering more proof that spring has begun, barred owls are hooting over my garage. This caterwauling usually starts around the beginning of February, and my resident pair was right on time. If you’re wondering what that sounds like, remember that barred owls have a very distinctive call that sounds like: “Who cooks for you? Who cooks for you’all?” Once you hear it, you can’t forget it.

Snowy owls are still around. Maine was overrun by snowy owls a few years ago, and this year’s invasion is modest by comparison, but it’s still better than historic averages. Not many seem to be hanging around Bangor, although one was spotted in Orono last week. At least six have taken up winter residence on the mountaintops of Acadia. Meanwhile, across Frenchman’s Bay at Schoodic Point, three snowy owls have been spotted cavorting on Schoodic Island, the large seabird nesting island across the channel from the Blueberry Hill parking lot.

Most of this year’s sightings have occurred in southern Maine, ranging from Kennebunk to Scarborough. I’ve seen one at Biddeford Pool. At least three snowy owls at Portland Jetport have been causing delight for birders, and headaches for airport security. Overexcited visitors have occasionally parked in bad places and encroached on secure areas. Worse, if visitors cause owls to fly toward the runways, security may have to use lethal means to remove the potential threat to aircraft. When birders misbehave, nobody wins.

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