Turkey Vulture

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The Turkey Vulture (Cathartes aura) is a bird  found throughout most of the  Americas. It is also known in some North American  regions as the turkey buzzard (or just buzzard), and in some areas of the Caribbean as the John crow or carrion crow.| [2]  One of three species in the genus  Cathartes , in the family  Cathartidae, the Turkey Vulture is the most widespread of the  New World vultures ,| [3]  ranging from southern  Canada  to the southernmost tip of  South America. It inhabits a variety of open and semi-open areas, including subtropical forests, shrublands, pastures, and deserts.| [1] It, like all new world "vultures", is not a "true vulture" in the sense of being related to the  Old World vultures  of Europe, Africa, and Asia. It looks nearly identical because of convergent evolution, where natural selection similarly shapes unrelated animals adapting to the same conditions. The Turkey Vulture is a scavenger  and feeds almost exclusively on  carrion .| [4]  It finds its food using its keen eyes and sense of smell, flying low enough to detect the gasses produced by the beginnings of the process of decay in dead animals.| [4]  In flight, it uses  thermals  to move through the air, flapping its wings infrequently. It roosts in large community groups. Lacking a syrinx —the vocal organ of birds—its only vocalizations are grunts or low hisses.| [5]  It nests in caves, hollow trees, or thickets. Each year it generally raises two chicks, which it feeds by regurgitation .| [6]  It has very few natural  predators .| [7]  In the  United States of America, the vulture receives legal protection under the  Migratory Bird Treaty Act of 1918 .| [8]

TaxonomyEnlargeA turkey vultureThe Turkey Vulture received its common name  from the resemblance of the adult's bald red head and its dark  plumage  to that of the male  Wild Turkey, while the name "vulture" is derived from the  Latin  word vulturus, meaning "tearer," and is a reference to its feeding habits.| [9]  The word buzzard is used by North Americans to refer to this bird, yet in the Old World this word refers to members of the genus  Buteo .| [10]  The  generic  term Cathartes means "purifier" and is the  Latinized  form from the  Greek  kathartēs/καθαρτης.| [11]  The species name, aura, is Latinized from the Native Mexican word for the bird, auroura.| [9]  The Turkey Vulture was first formally described by  Linnaeus  as Vultur aura in his  Systema Naturae  in 1758, and characterised as V. fuscogriseus, remigibus nigris, rostro albo ("brown-gray vulture, with black wings and a white beak").| [12]  It is a member of the family Cathartidae, along with the other six species of New World vultures, and included in the genus Cathartes, along with the  Greater Yellow-headed Vulture  and the  Lesser Yellow-headed Vulture. Like other New World vultures, the Turkey Vulture has a diploid chromosome number of 80.| [13]

The exact taxonomic  placement of the Turkey Vulture and the remaining six species of  New World Vultures  remains unclear.| [14]  Though both are similar in appearance and have similar  ecological roles, the New World and  Old World Vultures  evolved from different ancestors in different parts of the world. Just how different the two are is currently under debate, with some earlier authorities suggesting that the New World vultures are more closely related to storks .<sup class="reference" id="cite_ref-14">| [15]  More recent authorities maintain their overall position in the order  Falconiformes  along with the Old World Vultures<sup class="reference" id="cite_ref-15">| [16]  or place them in their own order, Cathartiformes.<sup class="reference" id="cite_ref-16">| [17]  The  South American Classification Committee  has removed the New World Vultures from  Ciconiiformes  and instead placed them in  Incertae sedis , but notes that a move to Falconiformes or Cathartiformes is possible.<sup class="reference" id="cite_ref-SACC_13-1">| [14] |   C. a. septentrionalis,  Ottawa,  Canada There are five subspecies of Turkey Vulture:
 * C. a. aura is the nominate subspecies. It is found from Mexico  south through  South America  and the  Greater Antilles . This subspecies occasionally overlaps its range with other subspecies. It is the smallest of the subspecies but is nearly indistinguishable from C. a. meridionalis in color.<sup class="reference" id="cite_ref-Amadon_17-0">| [18]
 * C. a. jota, the Chilean Turkey Vulture, is larger, browner, and slightly paler than C. a. ruficollis. The secondary feathers and wing coverts may have gray margins.<sup class="reference" id="cite_ref-Blake_18-0">| [19]
 * C. a. meridionalis, the Western Turkey Vulture, is a synonym for C. a. teter. C. a. teter was identified as a subspecies by Friedman in 1933, but in 1964 Alexander Wetmore  separated the western birds, which took the name meridionalis, which was applied earlier to a migrant from  South America . It breeds from southern  Manitoba, southern  British Columbia , central  Alberta  and  Saskatchewan  south to Baja California, south-central Arizona, and south-central Texas.<sup class="reference" id="cite_ref-19">| [20]  It is the most migratory subspecies, migrating as far as South America, where it overlaps the range of the smaller C. a. aura. It differs from the Eastern Turkey Vulture in color, as the edges of the lesser wing coverts are darker brown and narrower.<sup class="reference" id="cite_ref-Amadon_17-1">| [18]
 * C. a. ruficollis is found in Panama  south through  Uruguay  and  Argentina . It is also found on the island of  Trinidad .<sup class="reference" id="cite_ref-Brown_20-0">| [21]  It is darker and more black than C. a. aura, with brown wing edgings which are narrower or absent altogether.<sup class="reference" id="cite_ref-Brown_20-1">| [21]  The head and neck are dull red with yellow-white or green-white markings. Adults generally have a pale yellow patch on the crown of the head.<sup class="reference" id="cite_ref-Blake_18-1">| [19]
 * C. a. septentrionalis is known as the Eastern Turkey Vulture. The Eastern and Western Turkey Vultures differ in tail and wing proportions. It ranges from southeastern Canada  south through the eastern  United States . It is less migratory than C. a. meridionalis and rarely migrates to areas south of the United States.<sup class="reference" id="cite_ref-Amadon_17-2">| [18]

edit ] Description
EnlargeTracks in mud. Animation highlights the left print, showing the presence of vestigial webbing between the front toes. Note also the increased weight toward the front of the toes as the bird dipped its head down to take a drink.EnlargeA side view, showing the perforated nostrils.EnlargeLeucistic turkey vultureA large bird, it has a wingspan of 160–183 cm (63–72 in), a length of 62–81 cm (24–32 in), and weight of 0.8 to 2.3 kg (1.8 to 5.1 lb).<sup class="reference" id="cite_ref-Hilty_21-0">| [22] <sup class="reference" id="cite_ref-animaldiversity.ummz.umich.edu_22-0">| [23]  <sup class="reference" id="cite_ref-23">| [24]  While birds in the Northern limit of the species' range average around 2 kg (4.4 lb), vulture from the neotropics are generally smaller, averaging around 1.45 kg (3.2 lb).<sup class="reference" id="cite_ref-24">| [25]  <sup class="reference" id="cite_ref-25">| [26]  It displays minimal  sexual dimorphism ; sexes are identical in plumage and in coloration, although the female is slightly larger.<sup class="reference" id="cite_ref-26">| [27]  The body feathers are mostly brownish-black, but the  flight feathers  on the wings appear to be silvery-gray beneath, contrasting with the darker wing linings.<sup class="reference" id="cite_ref-Hilty_21-1">| [22]  The adult's head is small in proportion to its body and is red in color with few to no feathers. It also has a relatively short, hooked, ivory-colored beak.<sup class="reference" id="cite_ref-Terres_27-0">| [28] The irises of the eyes are gray-brown; legs and feet are pink-skinned, although typically stained white. The eye has a single incomplete row of eyelashes  on the upper lid and two rows on the lower lid.<sup class="reference" id="cite_ref-Pterylosis_28-0">| [29]

The two front toes of the foot are long and have small webs at their bases.<sup class="reference" id="cite_ref-Feduccia_29-0">| [30] Tracks are large, between 3.75 and 5.5 inches in length (9.5–14 cm) and 3.25 and 4 inches in width (8.2–10.2 cm), both measurements including claw marks. Toes are arranged in the classic, anisodactyl  pattern.<sup class="reference" id="cite_ref-Elbroch_30-0">| [31]  The feet are flat, relatively weak, and poorly adapted to grasping; the talons are also not designed for grasping, as they are relatively blunt.<sup class="reference" id="cite_ref-Concise_2-1">| [3]  In flight, the tail is long and slim, in contrast to that of the  Black Vulture. The nostrils are not divided by a septum, but rather are perforate; from the side one can see through the beak.<sup class="reference" id="cite_ref-31">| [32] It undergoes a  molt  in late winter to early spring. It is a gradual molt, which lasts until early autumn.<sup class="reference" id="cite_ref-Fergus_5-1">| [6] The immature bird has a gray head with a black beak tip; the colors change to those of the adult as the bird matures.<sup class="reference" id="cite_ref-32">| [33]  How long turkey vultures can live in captivity is not well known. While 21 years is generally given as a maximum age, the Gabbert Raptor Center on the University of Minnesota campus is home to a turkey vulture named Nero with a confirmed age of 37. The oldest wild captured banded bird was 16 years old.<sup class="reference" id="cite_ref-ADW_3-2">| [4]

Leucistic (sometimes mistakenly called " albino ") Turkey Vultures are sometimes seen.<sup class="reference" id="cite_ref-33">| [34]  The well-documented records come from the  United States of America, but this probably reflects the fact that such birds are more commonly reported by  birders  there, rather than a geographical variation. Even in the United States, white Turkey Vultures (although they presumably always turned up every now and then) were only discussed in birder and raptor  conservation circles and are not scientifically studied.<sup class="reference" id="cite_ref-34">| [35]

The Turkey Vulture, like most other vultures, has very few vocalization capabilities. Because it lacks a syrinx, it can only utter hisses and grunts.<sup class="reference" id="cite_ref-Miskimen_4-1">| [5]  It usually hisses when it feels threatened. Grunts are commonly heard from hungry young and from adults in their courtship display.

edit ] Distribution and habitat
EnlargeIn flight over Florida, USAEnlargeIn flight, from profileThe Turkey Vulture has a large range, with an estimated global occurrence of 28,000,000 km². It is the most abundant vulture in the Americas.<sup class="reference" id="cite_ref-Concise_2-2">| [3] Its global population is estimated to be 4,500,000 individuals.<sup class="reference" id="cite_ref-BirdLife_0-2">| [1]  It is found in open and semi-open areas throughout the  Americas  from southern Canada to  Cape Horn. It is a permanent resident in the southern United States, though northern birds may migrate  as far south as South America.<sup class="reference" id="cite_ref-ADW_3-3">| [4]  The Turkey Vulture is widespread over open country, subtropical forests, shrublands, deserts, and foothills.<sup class="reference" id="cite_ref-Kaufman_35-0">| [36]  It is also found in pastures, grasslands, and wetlands.<sup class="reference" id="cite_ref-BirdLife_0-3">| [1]  It is most commonly found in relatively open areas which provide nearby woods for nesting and it generally avoids heavily forested areas.<sup class="reference" id="cite_ref-Hilty_21-2">| [22] |   Turkey Vulture in Winters, CA, USA== edit ] Ecology and behavior== EnlargeSpread-winged adultEnlargeVultures on cellphone towerThe Turkey Vulture is gregarious and roosts in large community groups, breaking away to forage independently during the day. Several hundred vultures may roost communally in groups which sometimes even include Black Vultures. It roosts on dead, leafless trees, and will also roost on man-made structures such as water or microwave towers. Though it nests in caves, it does not enter them except during the breeding season.<sup class="reference" id="cite_ref-Fergus_5-2">| [6] The Turkey Vulture lowers its night-time body temperature by about 6 degrees Celsius to 34 °C (93 °F), becoming slightly  hypothermic .<sup class="reference" id="cite_ref-Feduccia_29-1">| [30]

This vulture is often seen standing in a spread-winged stance. The stance is believed to serve multiple functions: drying the wings, warming the body, and baking off bacteria. It is practiced more often following damp or rainy nights. This same behavior is displayed by other New World vultures, by  Old World vultures , and by  storks .<sup class="reference" id="cite_ref-snyder_6-1">| [7]  Like  storks , the Turkey Vulture often defecates on its own legs, using the evaporation of the water in the feces and/or urine to cool itself, a process known as  urohidrosis .<sup class="reference" id="cite_ref-36">| [37]  It cools the blood vessels in the unfeathered  tarsi  and feet, and causes white  uric acid  to streak the legs.<sup class="reference" id="cite_ref-37">| [38] |   Immatures attracted to the shore of  Lake Huron, Canada by beached dead fishThe Turkey Vulture has few natural predators. Adult, immature and fledging vultures may fall prey to golden eagles,  bald eagles  and  great horned owls , while eggs and nestlings may be preyed on by  mammals  such as  raccoons ,  virginia opossum  and  foxes .<sup class="reference" id="cite_ref-animaldiversity.ummz.umich.edu_22-1">| [23]  <sup class="reference" id="cite_ref-snyder_6-2">| [7]  Its primary form of defense is regurgitating semi-digested meat, a foul-smelling substance which deters most creatures intent on raiding a vulture nest.<sup class="reference" id="cite_ref-Fergus_5-3">| [6]  It will also sting if the predator is close enough to get the vomit in its face or eyes. In some cases, the vulture must rid its crop of a heavy, undigested meal in order to take flight to flee from a potential predator.<sup class="reference" id="cite_ref-Terres_27-1">| [28] Its life expectancy in the wild ranges upward of 16 years, with a captive life span of over 30 years being possible.<sup class="reference" id="cite_ref-38">| [39]  <sup class="reference" id="cite_ref-39">| [40]

The Turkey Vulture is awkward on the ground with an ungainly, hopping walk. It requires a great deal of effort to take flight, flapping its wings while pushing off the ground and hopping with its feet.<sup class="reference" id="cite_ref-Terres_27-2">| [28] While soaring, the Turkey Vulture holds its wings in a shallow  V-shape  and often tips from side to side, frequently causing the gray flight feathers to appear silvery as they catch the light. The flight of the Turkey Vulture is an example of static soaring flight, in which it flaps its wings very infrequently, and takes advantage of rising thermals  to stay soaring.<sup class="reference" id="cite_ref-USGS_40-0">| [41]

edit ] Diet
EnlargeFeeding on dead gull at Morro Bay, California, USAThe Turkey Vulture feeds primarily on a wide variety of  carrion , from small mammals to large grazers, preferring those recently dead, and avoiding carcasses that have reached the point of  putrefaction. It may rarely feed on plant matter, shoreline vegetation, pumpkin and other crops, live insects and other invertebrates .<sup class="reference" id="cite_ref-Kaufman_35-1">| [36]  In South America, it has been seen (and photographed) feeding on the fruits of the introduced  Oil Palm .<sup class="reference" id="cite_ref-41">| [42]  <sup class="reference" id="cite_ref-42">| [43]  It rarely, if ever, kills prey itself.<sup class="reference" id="cite_ref-Kritcher_43-0">| [44]  The Turkey Vulture can often be seen along roadsides feeding on  roadkill, or near bodies of water, feeding on washed-up fish.<sup class="reference" id="cite_ref-ADW_3-4">| [4]  It also will feed on fish or insects which have become stranded in shallow water.<sup class="reference" id="cite_ref-Fergus_5-4">| [6]  Like other vultures, it plays an important role in the  ecosystem  by disposing of carrion which would otherwise be a breeding ground for disease.<sup class="reference" id="cite_ref-cotton_44-0">| [45]

The Turkey Vulture forages by smell, an ability that is uncommon in the avian world. It often will fly low to the ground to pick up the scent of ethyl mercaptan, a gas produced by the beginnings of decay in dead animals.<sup class="reference" id="cite_ref-snyder_6-3">| [7]  The  olfactory lobe  of its  brain , responsible for processing smells, is particularly large compared to that of other animals.<sup class="reference" id="cite_ref-snyder_6-4">| [7]  This heightened ability to detect odors allows it to search for carrion below the  forest  canopy. King Vultures and  Black Vultures, which lack the ability to smell carrion, follow the Turkey Vulture to carcasses. The Turkey Vulture arrives first at the carcass, or with Greater Yellow-headed Vultures  or  Lesser Yellow-headed Vultures, which also share the ability to smell carrion.<sup class="reference" id="cite_ref-snyder_6-5">| [7]  It displaces the Yellow-headed Vultures from carcasses due to its larger size,<sup class="reference" id="cite_ref-cotton_44-1">| [45]  but is displaced in turn by the King Vulture, which makes the first cut into the skin of the dead animal. This allows the smaller, weaker-billed, Turkey Vulture access to food, because it cannot tear the tough hides of larger animals on its own. This is an example of mutual dependence  between species.<sup class="reference" id="cite_ref-Dietland_45-0">| [46]

edit ] Reproduction
EnlargeEgg and newly hatched chick less than one day oldThe breeding season of the Turkey Vulture varies according to latitude.<sup class="reference" id="cite_ref-46">| [47] In the southern United States, it commences in March, peaks in April to May, and continues into June.<sup class="reference" id="cite_ref-Georgia_47-0">| [48]  In more northerly latitudes, the season starts later and extends into August.<sup class="reference" id="cite_ref-48">| [49]  Courtship rituals of the Turkey Vulture involve several individuals gathering in a circle, where they perform hopping movements around the perimeter of the circle with wings partially spread. In the air, one bird closely follows another while flapping and diving.<sup class="reference" id="cite_ref-Kaufman_35-2">| [36]

Eggs are generally laid in the nesting site in a protected location such as a cliff, a cave, a rock crevice, a burrow, inside a hollow tree, or in a thicket. There is little or no construction of a nest; eggs are laid on a bare surface. Females generally lay two eggs, but sometimes one and rarely three. The eggs are cream-colored, with brown or lavender spots around their larger end.<sup class="reference" id="cite_ref-Kaufman_35-3">| [36] Both parents incubate, and the young hatch after 30 to 40 days. Chicks are altricial, or helpless at birth. Both adults feed the chicks by regurgitating  food for them, and care for them for 10 to 11 weeks. When adults are threatened while nesting, they may flee, or they may regurgitate on the intruder or feign death.<sup class="reference" id="cite_ref-Fergus_5-5">| [6] If the chicks are threatened in the nest, they defend themselves by hissing and regurgitating.<sup class="reference" id="cite_ref-Kaufman_35-4">| [36]  The young fledge at about nine to ten weeks. Family groups remain together until fall.<sup class="reference" id="cite_ref-Kaufman_35-5">| [36]

edit ] Relationship with humans
EnlargeSkullThe Turkey Vulture is sometimes accused of carrying anthrax  or hog cholera, both livestock diseases, on its feet or bill by cattle ranchers and is therefore occasionally perceived as a threat.<sup class="reference" id="cite_ref-mossman_49-0">| [50]  However, the virus that causes hog cholera is destroyed when it passes through the Turkey Vulture's digestive tract.<sup class="reference" id="cite_ref-Terres_27-3">| [28]  This species also may be perceived as a threat by farmers due to the similar Black Vulture's tendency to attack and kill newborn cattle. The Turkey Vulture does not kill live animals but will mix with flocks of Black Vultures and will scavenge what they leave behind. Nonetheless, its appearance at a location where a calf has been killed gives the incorrect impression that the Turkey Vulture represents a danger to calves.<sup class="reference" id="cite_ref-50">| [51] The droppings produced by Turkey Vultures and other vultures can harm or kill trees and other vegetation.<sup class="reference" id="cite_ref-51">| [52]  The Turkey Vulture can be held in captivity, though the  Migratory Bird Treaty Act  prevents this in the case of uninjured animals or animals capable of returning to the wild.<sup class="reference" id="cite_ref-cornell_52-0">| [53]  In captivity, it can be fed fresh meat, and younger birds will gorge themselves if given the opportunity.<sup class="reference" id="cite_ref-Terres_27-4">| [28]

The Turkey Vulture species receives special legal protections under the Migratory Bird Treaty Act of 1918  in the  United States ,<sup class="reference" id="cite_ref-FWS_7-1">| [8]  by the Convention for the Protection of Migratory Birds in  Canada ,<sup class="reference" id="cite_ref-cornell2_53-0">| [54]  and by the Convention for the Protection of Migratory Birds and Game Mammals in  Mexico .<sup class="reference" id="cite_ref-cornell2_53-1">| [54]  In the USA it is illegal to take, kill, or possess Turkey Vultures, and violation of the law is punishable by a fine of up to 15,000 US dollars and imprisonment of up to six months.<sup class="reference" id="cite_ref-cornell_52-1">| [53]  It is listed as a species of Least Concern by the  IUCN Red List. Populations appear to remain stable, and it has not reached the threshold of inclusion as a threatened species, which requires a decline of more than 30 percent in ten years or three generations.<sup class="reference" id="cite_ref-BirdLife_0-4">| [1]