Grackles in large flocks with blackbirds
Each year at about the middle of October, we experience the leaf-drop. The foliage that has been on the tree branches since mid-May finally responds to the weakening abscission layers on their petioles (leaf stalks). After a glorious color show that keeps us all looking, they fall to the ground. This leaf-dropping phenomenon was anticipated. We knew that it was about to happen, but it usually takes a weather event to bring down the bulk of the leaves that started to fall weeks ago. This year, it happened with quite a bang.
Sunday, Oct. 16, was a pleasant day with clear skies and temperatures in the 60s until mid-afternoon. While biking on that day I noted a couple of sunflowers and asters still in bloom. A monarch butterfly fluttered by. But I also noted dark clouds in the west that told of a weather change. Light rain moved in later, but it was a thunder shower, something not very common at this date, accompanied with fairly hard rain and strong winds that did the job of sending the foliage from the forest trees and leading us to the next phase of the autumn scene.
Once the leaves fall by mid-month, we experience two amazing happenings during these waning days of October. We are now in the time that I call AutWin, the period of time after the leaves fall and before the lasting snow cover. These weeks, maybe a month, are outstanding in the Northland woods. Also amazing is the golden glow the tamaracks now show in the surrounding swamps. Both of these fall phenomena cause us to take a closer look.
The forests at AutWin time reveal sights that get overlooked during the greens of summer and the shroud of snow in winter. Now we see just how numerous are the mosses, clubmosses, lichens and green ferns that are growing here. But it is not just the plants that give us views in this open woods. While walking here on sunlit days, I note the abundant threads between the branches. These thin silks show the spider movements at this time. In the penetrating rays, I see the fall flight of crane flies, moving about to get dominance for mating. In the cool dusk, late-season moths are flying. These critters mature in the chill of late October, taking advantage of a time of few predators to mate. And birds are here, too.
The movement of sparrows continues all this month. I have noted about 10 kinds. Juncos, white-throated, white-crowned, song and fox sparrows may be easy to see. Others, like swamp and Harris sparrows, are a bit harder to find. Though many nest here, all are heading south. Recently I saw a flock of tree sparrows, birds that nest in the far north, passing through the region as well. I'm also still seeing migrant robins, bluebirds, blue jays and lingering warblers. Among the raptors, red-tailed hawks, sharp-shinned hawks and bald eagles are flying by in the daytime, with saw-whet owls at night. Geese, swans, ducks and grebe keep us looking in the waterways. But it was a large flock of another group of songbirds that kept my interest this week, grackles and blackbirds.
With so many trees now having bare branches, I was able to see these birds as I came by. They were in a huge flock, most likely hundreds, which was quite noisy. And all were dark in color. This flock of black birds was indeed partially composed of a couple of species of blackbirds, but most were their larger cousins, the grackles. Grackles are dark birds, classified in the same family with the blackbirds, but they stand out from the others. Appearing almost black, they have an iridescence in the feathers that will frequently give a purple or green color to their plumage. Gregarious flocks were seen here earlier in spring and are now present again in fall. Unlike the rest of the black birds, these foot-long grackles were also very loud. They regularly gave calls of a "chuck" sound as well as creaky "koguba-leek" songs. Though seen mostly in trees, these birds were feeding on seeds, mostly corn, from nearby fields.
Scattered among the vocal grackles, I was able to discern three kinds of blackbirds: red-wing, Brewer's and rusty blackbirds. All three of these species are about 9 inches long. The red-wings that nest in the regional swamps where they fill the wetlands with their "konk-la-reee" songs are well known. Both the Brewer's and rusty blackbirds breed further to the north or west of here, but pass through during their migration. Despite plenty of songs earlier in the season, the blackbirds species were largely silent in this autumn scene. All four of these related migrants were on their way to their wintering sites, but pausing here to feed.
Though these birds are not always appreciated, I was glad to see and hear this flock as a part of the fall migration and AutWin.