It’s in Your Nature: Vultures are amazing soaring machines
You’re driving south on Route 209; the Lehigh River and Bear Mountain are on your right, and a light fog is lifting out of the valley. The sun has been warming the surroundings for about an hour, and a large bird is soaring out of the haze.
In the next minute as you approach the Mansion House Hill, three more soaring birds are in view. Before reaching Jim Thorpe, you’ve now seen a half-dozen of these amazing soaring machines. Most likely the raptors you just saw were turkey vultures. Turkey vultures are our most common and widely known vultures in the Times News area, Pennsylvania and the United States.
Soaring effortlessly on rising thermals or deflection winds along the ridges, the turkey vultures (TVs) are well suited and masters of soaring. They are dark brown, almost black, and have a 6-foot wingspan but weak breast muscles. They don’t flap much so they don’t need bulky muscles to weigh them down. In fact, because of those weaker muscles, TVs actually have a slight V shape pattern when you see them soaring. The slight V pattern is called a dihedral. They also rock in the slightest breezes, attesting to the weaker muscles. It is those two traits that can help you identify them from the other two large dark birds, the bald eagle and the black vulture.
The bald eagle has massive wings, and while soaring, they are held straight out from the body. Bald eagles have a wingspan of about 7½ feet, but at a distance, size is relative. Both the vulture species almost appear headless because their heads are featherless.
Black vultures, relative newcomers to our area, are different in a number of ways.
First, a black vulture’s head is featherless but doesn’t extend quite as far on the neck as the TV, and it’s gray/black in color. An adult turkey vulture’s head is reddish. Black vultures have shorter, broader wings and an unusually short tail. Black vultures are not soaring wizards as are TVs. They soar for a bit, take a couple of quick flaps, and then soar again. If you have ideal light conditions, you’ll notice a white patch of feathers on the underside of the wings at the end of the primaries.
Both vulture species are scavengers feasting on carrion. TVs are one of the few avian species with a great sense of smell. They rely on the slightest odor of a dead animal to drift upward with the warming air. Their sense of smell is amazing. Black vultures do not have that, but they typically soar much higher than turkey vultures and use the TV’s olfactory abilities to their advantage. They will follow the TVs to a roadkill or animal carcass. On the ground, the turkey vulture will intimidate the slightly smaller black vulture, but often a number of black vultures will descend on the normally solitary TV and claim the prize.
Two other facts: Black vultures, although considered scavengers, will kill newborn lambs and deer. An injured small animal would also be part of their diet. (TVs will not) Secondly, the black vulture has expanded its range northward. They’ve only been breeding in southeastern and eastern Pennsylvania since the early 1980s.
I’ve lived in the northern Lehigh Valley the past seven years. In winter I see more black vultures here than TVs. I find this surprising due to their southern origin. But they appear to have adjusted to the cold, and don’t rely as much on thermals, which are basically absent in colder winter weather. I think that explains their choice to stay farther north, while most TVs head farther south.
I won’t be around to see it, but I would guess with our changing climate, I would suspect they’ll soon be breeding as far north as New England in the next decade or two.
Be alert for both of these important scavengers as you “get out there.”
Test Your Outdoor Knowledge: True or False: Buzzards and vultures are one in the same.
Last Week’s Trivia Answer: How important are bats? A big brown bat may eat 3,000 insects each evening; many of which are beetle species so damaging to our crops.
Email Barry Reed at breed71@gmail.com