Tadeusz Strzelecki The male red-winged blackbird, with his powerful call, is one of the most reliable signs of spring. The call of the red-winged blackbird announces spring while the snow still falls. As black as pitch, with flame orange shoulders, the male perches on tall grasses and leafless branches high above New York’s bleak winter marshes. He is an unlikely herald, but he is one of the most reliable signs of spring. His call â€" a powerful “conk-a-ree-e†â€" trails off and settles over the reeds, embodying the ancient promise that spring will return.
Most years, the first males are trilling from newly established breeding territories by late February or early March, regardless of winter’s stubborn persistence.
Red-winged blackbirds (Agelaius phoeniceus) regularly overwinter in New York, which is an interesting adaptive strategy. Males establish and vigorously defend a territory. They can be observed puffing up their brilliant orange shoulder feathers and fanning their shining black tails to make the most of each loud call. Chase scenes, of one male ridding his territory of another, are not uncommon.
A bird who has managed to survive a mild winter has first pick of territories and gains the advantage of prime real estate. This advantage is measured by the females, who return north only slightly later than their male counterparts.
But not all New York winters are mild. This winter’s polar vortex was followed by numerous unnamed bouts of severe cold. Repeated snowstorms blocked access to food. The decision to stay may have been the final choice for many of these birds.
Adaptively speaking, in years like this it is advantageous not to be the “early bird.†The decision to migrate, or not, is important to the red-winged blackbird as a species; in this way there will always be reproducing adults, even if some perish in late or early severe weather.
Red-winged blackbirds are good examples of sexual dimorphism. The male is aptly named and nearly impossible to misidentify, but the brown, streaky bird next to him may not be the sparrow you suspect. Like sparrows, female red-winged blackbirds are well camouflaged, and at first glance are hard to differentiate except for their larger size and longer bill.
After selecting a protected site within the male’s territory, the female weaves a grass nest that she suspends between the reed stems. She lines its cup with mud and fine, soft grass, and lays three to four glossy eggs, which hatch in a little under two weeks. She is largely responsible for raising the nestlings, but as spring ripens and her chicks mature, she may produce several more nests in succession, with the same male or with competing males.
Red-winged blackbirds are strong fliers, and they flock together as summer cools to autumn. They are not long-distance migrants, generally overwintering in the southern United States, but some will fly as far south as Mexico and Central America.
Still others will stay home, betting on unknowable odds that the winter of 2015 will be milder than its predecessor.
