(This 890th Buffalo Sunday News column was first published on April 13, 2008.)
Cornell artist Louis Agassiz Frertes painting of three species in various plumages.
Top three, rusty blackbird; middle three, red-winged blackbird; bottom two, bobolink
Three blackbirds are common to the Niagara Frontier during our summers. They are the brown-headed cowbird, the red-winged blackbird and the common grackle. A fourth species, the rusty blackbird, passes through the region as a spring and fall migrant on its way between states south of New York and the boreal forests of Canada.
The rusty blackbird has shown what the Migratory Bird Center of the Smithsonian National Zoological Park identifies as "chronic long-term and acute short-term population declines, based both on breeding season and wintering ground surveys." Moreover, the Center indicates: "The decline, although one of the most profound for any North American species, is poorly understood." For that reason in February Center members formed the International Rusty Blackbird Technical Working Group to study this species and seek understanding of its decline. They feel that the information they gather may have implications for many other species as well.
As one part of the Group's study, it is asking birders across North America to report observations of this species. They may do so on the Cornell Ornithology Lab's E-Bird website or directly to Sam Droege, USGS Patuxent Wildlife Research Center, BARC EAST, Building 308, Room 124, 10300 Baltimore Ave, Beltsville, MD 20705.
There is a problem associated with this reporting. It is easy to confuse rusty blackbirds with other blackbirds. For that reason I offer some identification suggestions.
European starling. I include this less closely related species quite simply because it too is black. In all seasons it is easily separated from true blackbirds by its short tail. In breeding plumage males also have a long yellow bill. Females and juveniles are grayer. Introduced to this country in 1890, it is now by far our most common bird.
Red-winged blackbird. Adult males are black except for their red over yellow shoulders which they spread when they sing that standard of our marshes: kong-ka-reee. Females are brown striped birds. Be careful, however. Some males show much less shoulder color and are often confused with rusty blackbirds.
Brown-headed cowbird. Males are small blackbirds with, as the name suggests, brown heads. Females are plain brown.
Common grackle. Our largest black bird with a long wedge-like tail. In bright light the black is iridescent with purple highlights. Males and females are similar.
Bobolink. Like the starling, this is not a true blackbird, but most of its body is black. Breeding males are easily distinguished by the white of their backs and the pale yellow of the backs of their heads. Females look like large sparrows.
Rusty blackbird. With that background I turn to the species of interest here. Breeding males are very similar to red-winged blackbirds but they are all black. Remember, however, that some red-wings do not show those shoulder epaulettes either. Females are plain brown with a narrow black eye-line. There are two ways to distinguish this species: by its pale eyes and by its call from which its name is derived. Grackles are the only other species of this group that have this pale eye, but they differ in size and tail length. The rusty blackbirds song sounds like a rusty gate opening, a gurgling start followed by a high pitched squeek.
Rusty blackbirds are most common here in April and October. They often accompany the large flocks of migrating red-winged blackbirds that occur at this time as well. Both species are most often associated with wetlands. Although they can appear anywhere during migration, including occasionally at bird feeders, I have found them most often along Sour Springs Road in the Iroquois National Wildlife Refuge and in the marshes along River Road in North Tonawanda.
Here is what Arthur Cleveland Bent said about rusty blackbirds in 1958: "The spring migration of the rusty blackbirds is spectacular, noisy, and ubiquitous; the birds may be seen in enormous numbers almost anywhere, following the plowman as he cultivates his land, blackening the stubble or grain fields, filling the air in passing clouds, or gathering to sing in the leafless treetops along the roadsides or in the swampy woods and roosting at night in the swamps and sloughs."
Those numbers are long gone. In many areas the thousands of fifty years ago are down to dozens today.