Thursday, February 27, 2014

A Sure Sign of Spring

-->
Red Winged Blackbird (male).
 Which bird do you associate with the arrival of spring? The robin, right? It turns out that the appearance of a robin here on the South Shore is not an indication that spring is on its way. However spying a red-winged blackbird at your feeder: now that’s a different story.

Usually in early March, male red-winged blackbirds return to their breeding grounds, to prepare for the arrival of the females. Their aim is stake out, and guard, the best territory, so as to attract the most appealing mate.

My father likes to tell a story about a city-dwelling friend, who after hearing my dad’s excitement about the arrival of red-winged blackbirds on our deck, inquired “What do they look like?”

“Well,” said my dad, stating the obvious, “They are black birds, and they have a patch red on their wings.”

So yes, the name of the red-winged blackbird is indeed an apt descriptor. It is a medium-sized bird, just under two ounces in weight, and about 8.75 inches in length, with a 13-inch wingspan. Males are glossy black in color, with red and yellow badges, or “epaulettes,” on their shoulders, which they can display or conceal as needed. Females are less bold in color, usually a streaked dark brown, often with white above the eyes.

In spring, they are hard to miss – especially the males, who create quite a racket in their quest to be noticed by potential mates. Males will perch in high places and sing “Oak-a-ree!” or “Conk-la-ree!” all day long. Females are more apt to gather food and tend to the nest.

I live a stone’s throw from the Green Harbor River. In my back yard, a freshwater marsh divides the upland from a wide, pond-like section of the watercourse. This is prime habitat for red-winged blackbirds, who during the breeding season, favor marshes (both salt and fresh), rivers and streams, damp scrubby roadsides, and even the manmade ponds on golf courses. In winter, they might choose a drier habitat, such as an agricultural field, a wild meadow, or a grassy pasture.

So when they arrive here in spring, after wintering in warmer climes, they set about breeding and nesting. First the males each establish a territory. Next, when the females arrive, the males perch in prominent places, show off their colorful wing patches, and sing. Mate selection is undertaken by the females, but it’s not exclusive. A male may have up to fifteen different female mates at one time, and in a given season, most male red-winged blackbirds have at least two females nesting in their territory. Males actively defend their dominion. They will chase other birds away, fend off nest predators, and if they feel threatened, even harass large mammals including humans.

The females each select a site on which to build a nest. They use mud, grass and decayed vegetation to create a small cup which is seated low among densely-vegetated marsh grass, shrubs or trees. Females typically lay 3-6 eggs, which are pale blue-green or gray in color. After about 12 days of incubation, the fledglings hatch and the mother stays close-by for five weeks to feed them.

The diet of the red-winged blackbird varies. During the breeding season it is rich in protein, and includes insects like beetles, moths, grasshoppers, caterpillars and grubs. At other times of year, seeds and grains are staples.

The range of the red-winged blackbird spans the entire continental United States, most of Canada, and as far south as El Salvador, but the more highly populated areas are the Northeast, Midwest and the western US. Outside of nesting season, they congregate in extremely large flocks (think: millions), often with other types of blackbirds or starlings. They migrate with the seasons, concentrating where food and water are abundant.

As March approaches, the return of the red-winged blackbirds is nigh. Keep an eye out for brightly-colored males, who will bring some light and warmth to these dark, cold, dreary days, not only in a visual sense, but in a spiritual one as well. These shiny black birds with their patches of red and/or yellow on the shoulder are a sure sign of spring!

Sources:
http://www.allaboutbirds.org/guide/red-winged_blackbird/lifehistory

by Kezia Bacon, February 2014

Kezia Bacon's articles appear courtesy of the North and South Rivers Watershed Association, a local non-profit organization devoted to the preservation, restoration, maintenance and conservation of the North and South Rivers and their watershed. For membership information and a copy of their latest newsletter, contact NSRWA at (781) 659-8168 or visit www.nsrwa.org. To browse 15 years of Nature (Human and Otherwise) columns, visit http://keziabaconbernstein.blogspot.com

No comments: