Does anyone remember the days when the arrival of thousands of blackbirds announced that spring was on the way? As a child I recall the bare deciduous trees around my grandparents’ farm were peppered with redwings, cowbirds, starlings and grackles. Most farming people disliked these birds because grackles especially loved to eat grains and corn. Today, redwings still mark the change of the seasons but the clouds of mixed blackbirds are absent because humans have decimated their populations. When a shimmering blue – black Northern grackle appeared at my birdfeeder in late May I was delighted and hoped, that like the Redwing couple, this blackbird would choose to stay. In all these years I have never had a grackle nest here.
Last winter I developed a fascination and a deep respect for the grackle as a result of making regular visits to a Walmart in New Mexico that was built near a marsh. I couldn’t resist feeding the Great Tailed grackles hunks of bread as I observed these clever characters hopping about on the ground, dodging people and automobiles while searching for tidbits. These birds had surely adapted to human habitation and this fact impressed me greatly.Some of these birds always hung out on the roof with the fake owls that were put there to scare them away.
When the pair nested here down by the brook I was delighted. Although I heard the two conversing, for the longest time I never saw the female, who is not black but washed in chocolate brown. Two months later I have three young male grackles that visit my feeder along with both of their parents. Although they are omnivores – they eat insects, frogs berries etc. they love sunflower seeds too. If given a choice, grackles prefer to forage on the ground. They sometimes follow plows to catch invertebrates and mice, wade into water to catch small fish, pick leeches off the legs of turtles, steal worms from American Robins, and raid nests. Grackles have a hard keel on the inside of the upper mandible that they use for sawing open acorns. Typically they score the outside of the narrow end, then bite the acorn open. Northern populations migrate; the rest remain in areas east of the Rockies year round.
Along with some other species of grackles, the Northern grackle is known to practice “anting” – rubbing insects that contain formic acid on its feathers to deal with parasites. Though the exact mechanism is poorly understood, several studies have examined the ability of the Northern grackle to interpret the variability of the earth’s magnetic field. I have yet to learn all of the Northern grackle calls which are complicated by the birds’ uncanny ability to mimic other birds and sometimes even me! The grackles seem to enjoy my company, because whenever I am outside some members of the family join me usually perching high in a nearby pine.
They peer down at me with bright yellow-rimmed eyes often making remarks that I have yet to comprehend. Grackle intelligence was tested by posing glass cylinders full of water with bits of food floating just outside the birds reach. To grab the morsels, the birds had to drop in pebbles to raise the water levels. After a number of trials most of the grackles figured out that dropping pebbles into the water raised the water level so they could feed. They also learned that it was usually more efficient to use heavy pebbles to reach the snack, but if provided with too large stones the birds turned back to small pebbles to reach their goal.
Another test done had even more dramatic results. Silver and gold tubes of food were presented to the grackles but only the gold tubes had peanuts and bread in them. The grackles immediately chose the gold tubes, but when the food was placed in silver tubes the birds instantly chose them. These tests reveal not only problem solving ability but also the birds’ flexibility in terms of learning. It’s important to note that grackles outperformed three species in the Corvid family.
Unfortunately, the Northern grackle may be approaching extinction. Indiscriminate overuse of pesticides is probably the primary cause. What disturbs me is that most of the literature doesn’t address the issue of Northern grackle decimation, probably because it is considered a pest by humans. Many sites continue to suggest that the Northern grackle is widespread and common when just the opposite is the case.
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