The quiet times for birds seem to be persisting. I’m a bit surprised that a resurgence of post-breeding activity in the trees and at the feeders hasn’t materialized, at least on my property. Maybe we’ll see this happen finally, once September begins to usher in more cool fronts.
On the open waters of our local lakes, however, we are seeing a pronounced increase in the numbers of white water birds, other than swans and pelicans. These are the gulls and terns of the family Laridae.
Most gulls and terns nest colonially on large lakes to our north and west and are now beginning to trickle down to southern U.S. wintering grounds. I want to highlight here the three species that comprise the vast majority of these white visitors in our area.
First, the ring-billed gull. This is by far the commonest of the gulls here. Not only are they showing up on large and small lakes all over the area, they frequent supermarket parking lots, where they scavenge food scraps and proclaim their territories vocally from the tops of light poles. I think most all of us are well acquainted with this species, often referred to generically as “sea gulls.”
Perhaps more interesting, because of its daintiness and relative rarity compared with ring-bills, is the Bonaparte’s gull. “Bonies,” as seasoned birders call them, are quite a bit smaller than ring-bills and tend to prefer the open waters of our larger lakes. I do see them most every year, however, on Little Sand Lake.
In the spring, they have black heads, but by this time of year most have replaced these feathers with white, except for a prominent patch behind the eye. Bonies sit on the water buoyantly with tail held high. Their flight is very acrobatic and displays the prominent white leading edge, very different from the ring-bill.
Although I said that they prefer open water, gulls go to where food is most readily available. For bonies, the best place to see them right now is the Walker sewage settling ponds on the popular cutoff (73rd Street NW) between Highways 34 and 200. On Tuesday, I counted close to 250 there bobbing on the water and snatching up various morsels. In groups like this, you will occasionally hear their thin raspy squawk, totally unlike the high piercing calls of the ring-bills. Incidentally, although most gulls nest on the ground, this species builds its nests in coniferous trees in far northern Canada and Alaska.
The third species is the spectacular Caspian tern, which can appear on any of our lakes at this time. Terns, unlike gulls, feed by plunging into the water from the air – this behavior will distinguish the Caspian tern from any gull at a distance. The Caspian is the largest tern in the world and is considerably larger than the ring-billed gull. It has a strong flight and points its large, blood-red bill downward as it searches for fish near the surface. It often reveals itself with a very loud, grating call, sometimes described as sounding like a sheet being ripped.
One last note on a different topic. This is the time to be looking for migrating common nighthawks. At Hawk Ridge in Duluth on Tuesday, nearly 28,000 nighthawks were counted!