Three weeks ago, I knew Spring was coming. My first clue came from a pair of cardinals. Although the snow in my yard was still waist high, the day was sunny, the temperature was rising, and I heard a cardinal loudly singing its courtship/territory song (described as "whoit whoit whoit wacheer wacheer wacheer").
The next clue came from the chickadees. Whenever I hear the two-tone territorial song (first note higher than the second) given by males only, I know good weather is on the way.
The corker happened last week when I caught the unmistakable "kong-ka-reeee" of returning male red-winged blackbirds establishing their territories. To me, this means the back of winter has been broken.
We will most likely get more cold weather, and probably more snow, but the tides have turned and we can rejoice in the fact that spring is just around the corner. Next I expect to see a killdeer, hear resident woodpeckers drumming (again, to establish territories and attract mates), and then thrill as more and more species come "home" to breed.
Spring migration of birds is somewhat like a tide. The first wave of warm weather carries the hardiest species. These "early birds" are species that adapt their diet when usual food sources are covered by a late snowfall. Robins, for instance, feed primarily on worms, caterpillars and beetles (up to 80 percent in summer, fall, and winter). In the spring, however, their diet changes to 20 percent animal food and 80 percent plant food. Dried wild grapes, last year's apples, berries of all sorts still on the bush, and the fruit of sumac trees are just a few of the possibilities available before the ground thaws.
Red-winged blackbird down my road. He'll be there beside the river, When winter finally breaks its bones, He'll be king among the rushes, He'll be master of his home
(The song "Red-winged Blackbird" is from David Francey's new CD Torn Screen Door available from Lake Music, Ayer's Cliff, Quebec. Francey is Beth Girdler's husband.) The red-winged blackbird's diet is mostly made up of insects, especially weevils, beetles and grubs, but in the spring and summer, they will add weed seeds and farm crops to their shopping list. You may wonder what advantage an early arrival provides the first wave of migrants, especially when they run the risk of perishing if the weather turns cold for any length of time. The answer lies in the fact that the earliest birds lay claim to territories with the greatest available food source and best nesting sites. This advantage becomes even more apparent when you realize that the male bird situated in an optimal territory is more likely to attract a healthy mate, breed, and then successfully feed and rear young. He may even have time to raise a second batch of young, known as double brooding. The survival of healthy, well-fed young means that the genetic traits of the bird that makes optimal choices during the breeding season remain in the gene pool. The birds that "blow it" arrive too early and become too weak to defend a good territory, or come too late and are left with the least desirable real estate. Obviously, such birds are less likely to succeed in passing on the family name. This gamble of getting one's ETA just right is known as breeding strategy. This is Darwinism at its finest, survival of the fittest. My first robin sighting for 2000 occurred last Thursday. I looked out the big kitchen window and there it was, feeding on last year's fruit in our flowering crab tree. After Saturday night's dump of snow, my family witnessed a breathtaking sight. I was pleased to see a male red-winged blackbird - not common at feeders - land for a bite. I called for everyone to come see, and as we watched the bird, a flock of over 40 redwings descended from the heavens to join him and take advantage of an easy food supply after the storm. I would like to close with a request. Every year I make a wish when I see my first robin, sort of like wishing on a star. This year, when you see your first robin, make a wish too. Let's wish that more people learn to value wildlife and take on the challenge of protecting their world, and ours.
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