Nature's Notebook

The four black vultures found on the recent Salisbury-Sharon Christmas Bird Count (CBC) are evidence of this species’ rapid and continuing incursion into New England. Just a decade ago this bird, which is most abundant in the tropics, was unheard of in our region, and only in the past two winters has it been seen on the CBC.

My first encounter with it in this area occurred about six years ago, when I saw two individuals scavenging on the side of West Cornwall Road. Like the red-bellied woodpecker , whose range expanded northward from the 1970s onward, the black vulture is well on its way to becoming a common bird here.

You can witness — and help to document — the black vulture’s expansion. With practice, it is not difficult to distinguish this species from the more common turkey vulture , even without using binoculars. Both are very large, dark birds with small, unfeathered heads and impressive wingspans. In flight, the turkey vulture appears lanky, with long, fairly straight wings projecting out at a right angle from its body, and a noticeable tail. It holds its wings in a pronounced "V," and habitually rocks from side to side as it soars, as if trying to find its balance. This rocking behavior always clinches the identification of a turkey vulture.

In contrast, the black vulture appears stockier in flight than the turkey vulture. Its wings have a distinctly bow-shaped look, and, combined with its very short tail, make it seem nearly tailless. Its wings are held in a shallow "V," and it almost never rocks.

I’ve often watched black vultures soaring amid larger flocks of turkey vultures. They usually keep to themselves and soar in tighter circles than do turkey vultures.

Additionally, black vultures’ otherwise black wings have a conspicuous whitish triangle at the outer "hand," which is usually easy to spot. Turkey vultures’ wings are two-toned, with a darker leading edge (the front half) and lighter, but not white, trailing edge.

Seen on the ground or in trees, head color — red on the turkey vulture, grayish black on the black vulture — is usually a reliable field mark; however, young turkey vultures have black heads, so caution must be used.

It seems unavoidable to conclude that the increase of the black vulture in our region is another byproduct of our increasingly mild winters.

Upcoming at the Sharon Audubon Center: "Turtles!" on Saturday, Jan. 6, at 10 a.m.; and an "Owl Prowl" on Thursday, Jan. 11, at 7:30 p.m. Call 860-364-7467 for more information.

Fred Baumgarten is a naturalist and writer. He can be reached at fredb58@sbcglobal.net. His blog is at thatbirdblog.blogspot.com.