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The fascination with turkey vultures – an experience with Bill Clark

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Turkey Vultures begin their nightly kettle about 4:30 p.m. (Photo by Anita Westervelt)

Published in the McAllen Monitor February 4, 2023


Story and photos by Anita Westervelt


Turkey vultures glide into view one by one, rapidly filling the late afternoon sky over the forested acreage of Weslaco’s Frontera Audubon Society.


A similar gathering is happening just as quietly below as visitors advance to the back deck of the urban nature park’s historic Skaggs House, cameras at the ready.


The vultures are an evening spectacle during the winter; an audience in the park as the vultures kettle above is not so frequent, unless the occasion includes a special guest like expert raptor researcher, photographer, author and lecturer William (Bill) S. Clark.


Clark led us closer to the trees where the vultures would soon land. Turkey vultures are easy to identify in flight, he said. They display dihedral wings as they soar; flying with their wings in a V shape, tilted up. He pointed out two black vultures coming in, their wings almost flat. Their tail stubby compared to the long tail of the turkey vulture.


The classic Turkey Vulture dihedral wing flight display. (Photo by Anita Westervelt)

Turkey vultures are monomorphic, meaning male and female birds appear identical. Adult turkey vultures have a six-foot wingspan. They have red featherless heads, pink legs and contrary to most thinking, their plumage is not black, but shades of deep, rich browns. The tip of their red bill is white, making it appear as though they have a short bill.


Rich brown shades of a Turkey Vulture's top plumage. (Photo by Anita Westervelt)

A couple hundred turkey vultures were overhead, still pretty high in the sky, one or two dipping closer toward the viewers, sun glinting off their underwings as they changed angles to regain height and continue gathering. Clark pointed out the reflective quality of their two-toned underwings; wing tips and trailing feathers are white against the black leading-edge wings.


A Turkey Vulture's reflective, two-toned underwings. (Photo by Anita Westervelt)

Another identifying turkey vulture feature is their dramatic horaltic pose, where they sit with wings spread wide, apparently exposing their bodies to warm in the sun, especially after a chilly night.


One fact Clark imparted surprised several of us: turkey vultures take a bath every day, especially after eating and they spend three to four hours a day preening.


As daylight faded, the turkey vultures began to alight in the treetops. They prefer high-level roosts; branch selection may be influenced by age-related dominance, even unsettling a bird that’s taken another’s traditional perch. Turkey vultures are not the only species to roost communally, but the nightly show in Weslaco is unique in the Rio Grande Valley. Although turkey vultures roost en masse, they will head out the following morning to forage independently during the day.


A Turkey Vulture may insist on the same perch night after night. (Photo by Anita Westervelt)

The overarching question, of course, is how many vultures roost in the park? While no specific number was stated, a birder in the group did a math calculation using fingers and thumbs to form a circle – a valid bird counting technique – counting the birds in that tight circle and estimating the number of circles visible to us from our point on the ground. Her estimate was very nearly 1,000 turkey vultures.


A committee of Turkey Vultures bed down for the night. (Photo by Anita Westervelt)

Collective vulture nouns: Kettle when in flight; committee when on the ground or in trees; wake of vultures when feeding together.


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Weslaco’s nightly turkey vulture phenomenon


Turkey Vultures circle the skies over Weslaco's Frontera Audubon nature preserve each night. (Photo by Anita Westervelt)

Story and photo by Anita Westervelt


The sight of circling turkey vultures has been a nightly phenomenon in Weslaco’s Frontera Audubon Society grounds for around 20 years when a neighborhood resident began seeing about two hundred each night.


Large numbers of migrating turkey vultures join our resident vultures in October and November, congregating in the evenings in the safety of the center’s habitat. Turkey vultures range from southern Canada to the southern tip of South America. They migrate to southern regions as freezing temperatures make locating food difficult. They return to their home range in March.


The center’s numbers have increased through the years and recent counts tally between 800 and 1,000 turkey vultures nightly. A few black vultures are usually in the mix. Vultures are not aggressive nor are they a threat to humans. They are monogamous and can survive in the wild for more than 40 years. If one partner perishes, they will find another mate.


Frontera Audubon Director Christine Warren recalled that when she first took over, about 12 years ago, there had been some discussion about discouraging the turkey vultures from roosting in the nature center. However, there had been some loss of habitat along the Rio Grande River about that time, the number of vultures coming to the park increased and the park’s 15 acres seemed such a valuable habitat for the wintering over turkey vultures.


Because of the number of roosting vultures, areas of the park are smelly, especially in the heat, according to Warren. Good spring rains will wash away the white droppings left by the birds, and everything will be fresh again for several months. The center this year has added canopies over three of the park’s nature trail benches, keeping them clean for other birders and park visitors, she noted.


Frontera Audubon is located at 1101 S. Texas Blvd, in Weslaco. Their hours are Tuesday – Saturday 8 a.m. to 4 p.m. and Sunday, noon to 4 p.m.


After hours, visitors are welcome to watch the vultures as they come in for the night. The parking lot is closed at 4 p.m., but visitors may park in the facility’s driveway. The back lawn of Skaggs House is open after hours where visitors can watch the vultures. The turkey vultures begin coming into view about 4:30 p.m.


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