The turkey vulture (''Cathartes aura'') is the most widespread of the
New World vulture
The New World vulture or condor family, Cathartidae, contains seven extant species in five genera. It includes five extant vultures and two extant condors found in warm and temperate areas of the Americas. The "New World" vultures were widespread ...
s.
One of three species in the genus ''
Cathartes
The genus ''Cathartes'' includes medium-sized to large carrion-feeding birds in the New World vulture (Cathartidae) family. The three extant species currently classified in this genus occur widely in the Americas. There is one extinct species kn ...
'' of the family
Cathartidae
The New World vulture or condor family, Cathartidae, contains seven extant species in five genera. It includes five extant vultures and two extant condors found in warm and temperate areas of the Americas. The "New World" vultures were widespread ...
, the turkey vulture ranges 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.
Like all New World vultures, it is not closely related to the
Old World vulture
Old World vultures are vultures that are found in the Old World, i.e. the continents of Europe, Asia and Africa, and which belong to the family Accipitridae, which also includes eagles, buzzards, kites, and hawks.
Old World vultures are not clos ...
s of Europe, Africa, and Asia. The two groups strongly resemble each other because of
convergent evolution
Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last com ...
; natural selection often leads to similar body plans in animals that adapt independently to similar conditions.
The turkey vulture is a
scavenger
Scavengers are animals that consume dead organisms that have died from causes other than predation or have been killed by other predators. While scavenging generally refers to carnivores feeding on carrion, it is also a herbivorous feeding b ...
and feeds almost exclusively on
carrion
Carrion () is the decaying flesh of dead animals, including human flesh.
Overview
Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters (or scavengers) include crows, vultures, c ...
.
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.
In flight, it uses
thermal
A thermal column (or thermal) is a rising mass of buoyant air, a convective current in the atmosphere, that transfers heat energy vertically. Thermals are created by the uneven heating of Earth's surface from solar radiation, and are an example ...
s to move through the air, flapping its wings infrequently. It roosts in large community groups. Lacking a
syrinx
In classical Greek mythology, Syrinx (Greek Σύριγξ) was a nymph and a follower of Artemis, known for her chastity. Pursued by the amorous god Pan, she ran to a river's edge and asked for assistance from the river nymphs. In answer, sh ...
—the vocal organ of birds—its only vocalizations are grunts or low hisses.
It nests in caves, hollow trees, or thickets. Each year it generally raises two chicks, which it feeds by
regurgitation.
It has very few natural
predator
Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...
s.
In the United States, the vulture receives legal protection under the
Migratory Bird Treaty Act of 1918
The Migratory Bird Treaty Act of 1918 (MBTA), codified at (although §709 is omitted), is a United States federal law, first enacted in 1918 to implement the convention for the protection of migratory birds between the United States and Canada . ...
.
Names
''Cathartes aura'' is the scientific name of the turkey vulture. It is also known in some North American regions as buzzard or turkey buzzard and in some areas of the Caribbean as the John crow or carrion crow.
Taxonomy
![Turkey vulture (Cathartes aura) in flight](https://upload.wikimedia.org/wikipedia/commons/4/40/Turkey_vulture_%28Cathartes_aura%29_in_flight.JPG)
The turkey vulture received its
common name
In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contrast ...
from the resemblance of the adult's bald red head and its dark
plumage
Plumage ( "feather") is a layer of feathers that covers a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage differ between species and subspecies and may vary with age classes. Within species, ...
to that of the male
wild turkey
The wild turkey (''Meleagris gallopavo'') is an Upland game bird, upland ground bird native to North America, one of two extant species of Turkey (bird), turkey and the heaviest member of the order Galliformes. It is the ancestor to the domestic ...
, while the name "vulture" is derived from the
Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
word ''vulturus'', meaning "tearer", and is a reference to its feeding habits.
The word ''buzzard'' is used by North Americans to refer to this bird, yet in the Old World that term refers to members of the genus ''
Buteo
''Buteo'' is a genus of medium to fairly large, wide-ranging raptors with a robust body and broad wings. In the Old World, members of this genus are called "buzzards", but "hawk" is used in the New World (Etymology: ''Buteo'' is the Latin name o ...
''. The turkey vulture was first formally described by
Carl Linnaeus
Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the ...
as ''Vultur aura'' in his 1758
10th edition of ''Systema Naturae'', and characterised as "''V. fuscogriseus, remigibus nigris, rostro albo''" ("brown-gray vulture, with black wing flight feathers and a white beak"). 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
The greater yellow-headed vulture (''Cathartes melambrotus''), also known as the forest vulture, is a species of bird in the New World vulture family Cathartidae. It was considered to be the same species as the lesser yellow-headed vulture until ...
and the
lesser yellow-headed vulture
The lesser yellow-headed vulture (''Cathartes burrovianus'') also known as the savannah vulture, is a species of bird in the New World vulture family Cathartidae. It was considered to be the same species as the greater yellow-headed vulture unti ...
. Like other New World vultures, the turkey vulture has a
diploid
Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respectively ...
chromosome number of 80.
The
taxonomic
Taxonomy is the practice and science of categorization or classification.
A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. ...
placement of the turkey vulture and the remaining six species of
New World vulture
The New World vulture or condor family, Cathartidae, contains seven extant species in five genera. It includes five extant vultures and two extant condors found in warm and temperate areas of the Americas. The "New World" vultures were widespread ...
s has been in flux.
[
Remsen, J. V. Jr.; C. D. Cadena; A. Jaramillo; M. Nores; J. F. Pacheco; M. B. Robbins; T. S. Schulenberg; F. G. Stiles; D. F. Stotz & K. J. Zimmer. (2007)]
''A classification of the bird species of South America.''
South American Classification Committee. Retrieved 2007–10–15
Though both are similar in appearance and have similar
ecological roles, the New World and
Old World vultures
Old World vultures are vultures that are found in the Old World, i.e. the continents of Europe, Asia and Africa, and which belong to the family Accipitridae, which also includes eagles, buzzards, Kite (bird), kites, and hawks.
Old World vultures ...
evolved from different ancestors in different parts of the world. Some earlier authorities suggested that the New World vultures were more closely related to
storks
Storks are large, long-legged, long-necked wading birds with long, stout bills. They belong to the family called Ciconiidae, and make up the order Ciconiiformes . Ciconiiformes previously included a number of other families, such as herons and ...
. More recent authorities maintained their overall position in the order
Falconiformes
The order Falconiformes () is represented by the extant family Falconidae (falcons and caracaras) and a handful of enigmatic Paleogene species. Traditionally, the other bird of prey families Cathartidae (New World vultures and condors), Sagitt ...
along with the Old World vultures or place them in their own order,
Cathartiformes
The order Cathartiformes of raptors or birds of prey includes the New World vultures and the now-extinct Teratornithidae. These raptors are classified by most taxonomic authorities in the order Accipitriformes (which includes the eagles and hawk ...
.
However, recent genetic studies indicate that neither New World nor Old World vultures are close to
falcon
Falcons () are birds of prey in the genus ''Falco'', which includes about 40 species. Falcons are widely distributed on all continents of the world except Antarctica, though closely related raptors did occur there in the Eocene.
Adult falcons ...
s, nor are New World vultures close to storks.
Both are
basal members of the clade
Afroaves
Afroaves is a clade of birds, consisting of the kingfishers and kin (Coraciiformes), woodpeckers and kin (Piciformes), hornbills and kin (Bucerotiformes), trogons (Trogoniformes), cuckoo roller ( Leptosomiformes), mousebirds ( Coliiformes), owls ...
,
with Old World vultures comprising several groups within the family
Accipitridae
The Accipitridae is one of the three families within the order Accipitriformes, and is a family of small to large birds with strongly hooked bills and variable morphology based on diet. They feed on a range of prey items from insects to medium-s ...
, also containing eagles, kites, and hawks,
while New World vultures in Cathartiformes are a
sister group
In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree.
Definition
The expression is most easily illustrated by a cladogram:
Taxon A and t ...
to
Accipitriformes
The Accipitriformes (; from Latin ''accipiter''/''accipitri-'' "hawk", and New Latin ''-formes'' "having the form of") are an order of birds that includes most of the diurnal birds of prey, including hawks, eagles, vultures, and kites, but not f ...
(containing the
osprey
The osprey (''Pandion haliaetus''), , also called sea hawk, river hawk, and fish hawk, is a diurnal, fish-eating bird of prey with a cosmopolitan range. It is a large raptor reaching more than in length and across the wings. It is brown o ...
and
secretarybird
The secretarybird or secretary bird (''Sagittarius serpentarius'') is a large, mostly terrestrial bird of prey. Endemic to Africa, it is usually found in the open grasslands and savanna of the sub-Saharan region. John Frederick Miller describe ...
along with Accipitridae
).
![Eastern Turkey Vulture (Canada)](https://upload.wikimedia.org/wikipedia/commons/f/f1/Eastern_Turkey_Vulture_%28Canada%29.jpg)
There are five subspecies of turkey vulture:
* ''C. a. aura'' is the nominate subspecies. It is found from
Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
south through
South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...
and the
Greater Antilles
The Greater Antilles ( es, Grandes Antillas or Antillas Mayores; french: Grandes Antilles; ht, Gwo Zantiy; jam, Grieta hAntiliiz) is a grouping of the larger islands in the Caribbean Sea, including Cuba, Hispaniola, Puerto Rico, Jamaica, and ...
. 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.
* ''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.
* ''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
Frank Alexander Wetmore (June 18, 1886 – December 7, 1978) was an American ornithologist and avian paleontologist. He was the sixth Secretary of the Smithsonian Institution.
Early life and education
The son of a Country Physician, Frank Al ...
separated the western birds, which took the name ''meridionalis'', which was applied earlier to a migrant from
South America
South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...
. It breeds from southern
Manitoba
Manitoba ( ) is a Provinces and territories of Canada, province of Canada at the Centre of Canada, longitudinal centre of the country. It is Canada's Population of Canada by province and territory, fifth-most populous province, with a population o ...
, southern
British Columbia
British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...
, central
Alberta
Alberta ( ) is one of the thirteen provinces and territories of Canada. It is part of Western Canada and is one of the three prairie provinces. Alberta is bordered by British Columbia to the west, Saskatchewan to the east, the Northwest Ter ...
and
Saskatchewan
Saskatchewan ( ; ) is a Provinces and territories of Canada, province in Western Canada, western Canada, bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, to the northeast by Nunavut, and on t ...
south to Baja California, south-central Arizona, southeastern
New Mexico
)
, population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano)
, seat = Santa Fe
, LargestCity = Albuquerque
, LargestMetro = Tiguex
, OfficialLang = None
, Languages = English, Spanish ( New Mexican), Navajo, Ker ...
, and south-central Texas. 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.
* ''C. a. ruficollis'', the tropical turkey vulture, is found in
Panama
Panama ( , ; es, link=no, Panamá ), officially the Republic of Panama ( es, República de Panamá), is a transcontinental country spanning the southern part of North America and the northern part of South America. It is bordered by Cos ...
south through
Uruguay
Uruguay (; ), officially the Oriental Republic of Uruguay ( es, República Oriental del Uruguay), is a country in South America. It shares borders with Argentina to its west and southwest and Brazil to its north and northeast; while bordering ...
and
Argentina
Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...
. It is also found on the island of
Trinidad
Trinidad is the larger and more populous of the two major islands of Trinidad and Tobago. The island lies off the northeastern coast of Venezuela and sits on the continental shelf of South America. It is often referred to as the southernmos ...
.
It is darker and more black than ''C. a. aura'', with brown wing edgings which are narrower or absent altogether.
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.
* ''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
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...
south through the eastern
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...
. It is less migratory than ''C. a. meridionalis'' and rarely migrates to areas south of the United States.
Description
![Cathartes aura cranium](https://upload.wikimedia.org/wikipedia/commons/5/5c/Cathartes_aura_cranium.jpg)
A large bird, it has a wingspan of , a length of , and weight of .
Birds in the northern limit of the species' range average larger in size than the vulture from the
neotropics
The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropics, tropical Ecoregion#Terrestrial, terrestrial ecoregions of the Americas and the entire South American temperat ...
. 124 birds from
Florida
Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...
averaged while 65 and 130 birds from
Venezuela
Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, República Bolivariana de Venezuela), is a country on the northern coast of South America, consisting of a continental landmass and many islands and islets in th ...
were found to average , respectively.
[''CRC Handbook of Avian Body Masses, 2nd Edition'' (2008). John B. Dunning Jr. (Editor). CRC Press. .] It displays minimal
sexual dimorphism
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...
; sexes are identical in plumage and in coloration, and are similar in size. The body feathers are mostly brownish-black, but the
flight feather
Flight feathers (''Pennae volatus'') are the long, stiff, asymmetrically shaped, but symmetrically paired pennaceous feathers on the wings or tail of a bird; those on the wings are called remiges (), singular remex (), while those on the tail ...
s on the wings appear to be silvery-gray beneath, contrasting with the darker wing linings.
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.
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
eyelash
An eyelash (also called lash) (Latin: ''Cilia'') is one of the hairs that grows at the edge of the eyelids. It grows in one layer on the edge of the upper and lower eyelids. Eyelashes protect the eye from debris, dust, and small particles and p ...
es on the upper lid and two rows on the lower lid.
![Eastern Turkey Vulture in flight, Canada](https://upload.wikimedia.org/wikipedia/commons/6/6c/Eastern_Turkey_Vulture_in_flight%2C_Canada.jpg)
The two front toes of the foot are long and have small webs at their bases.
Tracks are large, between in length and in width, both measurements including claw marks. Toes are arranged in the classic,
anisodactyl
In biology, dactyly is the arrangement of digits (fingers and toes) on the hands, feet, or sometimes wings of a tetrapod animal. It comes from the Greek word δακτυλος (''dáktylos'') = "finger".
Sometimes the ending "-dactylia" is use ...
pattern.
The feet are flat, relatively weak, and poorly adapted to grasping; the talons are also not designed for grasping, as they are relatively blunt.
In flight, the tail is long and slim. The
black vulture
The black vulture (''Coragyps atratus''), also known as the American black vulture, Mexican vulture, zopilote, urubu, or gallinazo, is a bird in the New World vulture family whose range extends from the northeastern United States to Peru, Cen ...
is relatively shorter-tailed and shorter-winged, which makes it appear rather smaller in flight than the turkey vulture, although the body masses of the two species are roughly the same. The nostrils are not divided by a septum, but rather are perforate; from the side one can see through the beak. It undergoes a
molt
In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is the manner in which an animal routinely casts off a part of its body (often, but not always, an outer ...
in late winter to early spring. It is a gradual molt, which lasts until early autumn.
The immature bird has a gray head with a black beak tip; the colors change to those of the adult as the bird matures. Captive longevity is not well known. there are two captive birds over 45 years old: the Gabbert Raptor Center on the University of Minnesota campus is home to a turkey vulture named Nero with a confirmed hatch-year of 1974,
and another male bird, named Lord Richard, lives at the
Lindsay Wildlife Experience
Lindsay Wildlife Experience, formerly known as Lindsay Wildlife Museum, is a family museum and wildlife rehabilitation center in Walnut Creek, California. Lindsay is the first wildlife hospital established in the United States, and a popular fam ...
in Walnut Creek, CA. Lord Richard hatched in 1974 and arrived at the museum later that year. The oldest wild captured banded bird was 16 years old.
Leucistic
Leucism () is a wide variety of conditions that result in the partial loss of pigmentation in an animal—causing white, pale, or patchy coloration of the skin, hair, feathers, scales, or cuticles, but not the eyes. It is occasionally spelled ' ...
(sometimes mistakenly called "
albino
Albinism is the congenital absence of melanin in an animal or plant resulting in white hair, feathers, scales and skin and pink or blue eyes. Individuals with the condition are referred to as albino.
Varied use and interpretation of the term ...
") turkey vultures are sometimes seen.
Like most other vultures, the turkey vulture has very few vocalization capabilities. Because it lacks a
syrinx
In classical Greek mythology, Syrinx (Greek Σύριγξ) was a nymph and a follower of Artemis, known for her chastity. Pursued by the amorous god Pan, she ran to a river's edge and asked for assistance from the river nymphs. In answer, sh ...
, it can only utter hisses and grunts.
Distribution and habitat
The turkey vulture has a large range, with an estimated global occurrence of . It is the most widely distributed vulture in the Americas and rivals its cousin the black vulture as the most abundant raptorial bird worldwide.
Its global population is estimated to be 18,000,000 individuals.
It is found in open and semi-open areas throughout the
Americas
The Americas, which are sometimes collectively called America, are a landmass comprising the totality of North and South America. The Americas make up most of the land in Earth's Western Hemisphere and comprise the New World.
Along with th ...
from southern Canada to
Cape Horn
Cape Horn ( es, Cabo de Hornos, ) is the southernmost headland of the Tierra del Fuego archipelago of southern Chile, and is located on the small Hornos Island. Although not the most southerly point of South America (which are the Diego Ramírez ...
. It is a permanent resident in the southern United States, though northern birds may
migrate as far south as South America.
The turkey vulture is widespread over nearly all American habitats but they tend to show particular habitat preferences.
[ It is most commonly found in relatively open areas which ]juxtapose
Juxtaposition is an act or instance of placing two elements close together or side by side. This is often done in order to compare/contrast the two, to show similarities or differences, etc.
Speech
Juxtaposition in literary terms is the showin ...
with woodland
A woodland () is, in the broad sense, land covered with trees, or in a narrow sense, synonymous with wood (or in the U.S., the ''plurale tantum'' woods), a low-density forest forming open habitats with plenty of sunlight and limited shade (see ...
, which are important both for nesting and roosting. Furthermore, turkey vultures in North America generally avoid enclosed forested areas that may hamper their ability to take flight and tend to often favor hill or low mountainous areas that make catching flight easier with less effort. This species can be seen over open country
"Open Country" is a designation used for some UK access land.
It was first defined under the National Parks and Access to the Countryside Act 1949 (and extended by the Countryside Act 1968), and was land over which an appropriate access agreeme ...
, including grassland
A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur natur ...
s but are often absent from completely treeless areas such as some parts of the prairie
Prairies are ecosystems considered part of the temperate grasslands, savannas, and shrublands biome by ecologists, based on similar temperate climates, moderate rainfall, and a composition of grasses, herbs, and shrubs, rather than trees, as the ...
s or Great Plains
The Great Plains (french: Grandes Plaines), sometimes simply "the Plains", is a broad expanse of flatland in North America. It is located west of the Mississippi River and east of the Rocky Mountains, much of it covered in prairie, steppe, an ...
.[ Additionally, they may adapt to ]tropical
The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in
the Southern Hemisphere at S. The tropics are also referred to ...
and subtropical forests, shrubland
Shrubland, scrubland, scrub, brush, or bush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity. It m ...
s, desert
A desert is a barren area of landscape where little precipitation occurs and, consequently, living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to denudation. About on ...
s and semi-desert
A semi-arid climate, semi-desert climate, or steppe climate is a dry climate sub-type. It is located on regions that receive precipitation below potential evapotranspiration, but not as low as a desert climate. There are different kinds of semi-ar ...
, wetland
A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. The ...
s and foothill
Foothills or piedmont are geographically defined as gradual increases in elevation at the base of a mountain range, higher hill range or an upland area. They are a transition zone between plains and low relief hills and the adjacent topograp ...
s. Evidence indicates agricultural land
Agricultural land is typically land ''devoted to'' agriculture, the systematic and controlled use of other organism, forms of lifeparticularly the rearing of livestock and production of cropsto produce food for humans. It is generally synonymous ...
is key habitat for turkey vultures, mainly pastureland
Pasture (from the Latin ''pastus'', past participle of ''pascere'', "to feed") is land used for grazing. Pasture lands in the narrow sense are enclosed tracts of farmland, grazed by domesticated livestock, such as horses, cattle, sheep, or swine ...
or other low-input farmland for foraging and roosting but they tend to only occur ephemerally as flyovers around row-crop type agriculture. Other manmade habitats can be used, with the species regularly seen over urban areas throughout its range, though they tend to use them more when not breeding, being unable to nest without appropriate habitats, and do not occur as an urban bird nearly as routinely as do black vultures in the tropics and subtropics.
This bird with its crow-like aspect gave foot to the naming of the Quebrada de los Cuervos
The Quebrada de los Cuervos (Spanish for ''Crows Ravine'') is an important landform in Treinta y Tres Department, Uruguay.
Crossed by the Yerbal Chico creek, it constitutes a natural protected area. This Important Bird Area (IBA) is inhabited by ...
(Crows Ravine) in Uruguay
Uruguay (; ), officially the Oriental Republic of Uruguay ( es, República Oriental del Uruguay), is a country in South America. It shares borders with Argentina to its west and southwest and Brazil to its north and northeast; while bordering ...
, where they dwell together with the lesser yellow-headed vulture and the black vulture.
Ecology and behavior
The 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 often on dead, leafless trees as well as low-density conifers, 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. The turkey vulture lowers its night-time body temperature by about 6 degrees Celsius to , becoming slightly hypothermic
Hypothermia is defined as a body core temperature below in humans. Symptoms depend on the temperature. In mild hypothermia, there is shivering and mental confusion. In moderate hypothermia, shivering stops and confusion increases. In severe h ...
.
This vulture is often seen standing in a spread-winged or horaltic 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 vulture
Old World vultures are vultures that are found in the Old World, i.e. the continents of Europe, Asia and Africa, and which belong to the family Accipitridae, which also includes eagles, buzzards, kites, and hawks.
Old World vultures are not clos ...
s, and by stork
Storks are large, long-legged, long-necked wading birds with long, stout bills. They belong to the family called Ciconiidae, and make up the order Ciconiiformes . Ciconiiformes previously included a number of other families, such as herons an ...
s. 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
Urohidrosis (sometimes misspelled "urohydrosis") is the habit in some birds of defecating onto the scaly portions of the legs as a cooling mechanism, using evaporative cooling of the fluids. Several species of storks and New World vultures exhibi ...
. It cools the blood vessels in the unfeathered tarsi and feet, and causes white uric acid
Uric acid is a heterocyclic compound of carbon, nitrogen, oxygen, and hydrogen with the formula C5H4N4O3. It forms ions and salts known as urates and acid urates, such as ammonium acid urate. Uric acid is a product of the metabolic breakdown of ...
to streak the legs.
The turkey vulture has few natural predators and the few recorded predators appear to take them quite infrequently. Fledging, immature and adult vultures, in descending likelihood of predation, may fall prey to great horned owl
The great horned owl (''Bubo virginianus''), also known as the tiger owl (originally derived from early naturalists' description as the "winged tiger" or "tiger of the air"), or the hoot owl, is a large owl native to the Americas. It is an extrem ...
s, golden eagle
The golden eagle (''Aquila chrysaetos'') is a bird of prey living in the Northern Hemisphere. It is the most widely distributed species of eagle. Like all eagles, it belongs to the family Accipitridae. They are one of the best-known bird of p ...
s, bald eagle
The bald eagle (''Haliaeetus leucocephalus'') is a bird of prey found in North America. A sea eagle, it has two known subspecies and forms a species pair with the white-tailed eagle (''Haliaeetus albicilla''), which occupies the same niche as ...
s and potentially red-tailed hawk
The red-tailed hawk (''Buteo jamaicensis'') is a bird of prey that breeds throughout most of North America, from the interior of Alaska and northern Canada to as far south as Panama and the West Indies. It is one of the most common members with ...
s, while eggs and nestlings may be preyed on by mammal
Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...
s such as raccoon
The raccoon ( or , ''Procyon lotor''), sometimes called the common raccoon to distinguish it from other species, is a mammal native to North America. It is the largest of the procyonid family, having a body length of , and a body weight of ...
s and opossum
Opossums () are members of the marsupial order Didelphimorphia () endemic to the Americas. The largest order of marsupials in the Western Hemisphere, it comprises 93 species in 18 genera. Opossums originated in South America and entered North ...
s. Fox
Foxes are small to medium-sized, omnivorous mammals belonging to several genera of the family Canidae. They have a flattened skull, upright, triangular ears, a pointed, slightly upturned snout, and a long bushy tail (or ''brush'').
Twelve sp ...
es can occasionally ambush an adult but species that can climb are more likely to breach and predate nests than adults, while dog
The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the wolf. Also called the domestic dog, it is derived from the extinct Pleistocene wolf, and the modern wolf is the dog's nearest living relative. Do ...
s may sometimes rarely kill a turkey vulture as well.[Jackson, J. A. (1983). Nesting phenology, nest site selection, and reproductive success of the Black and Turkey vulture. ''Vulture biology and management.'' (Wilbur, S. R. and J. A. Jackson, Eds.) Univ. of California Press, Berkeley, CA. pp.245-270.] Its primary form of defense is regurgitating semi-digested meat, a foul-smelling substance, which deters most creatures intent on raiding a vulture nest. 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
A crop is a plant that can be grown and harvested extensively for profit or subsistence. When the plants of the same kind are cultivated at one place on a large scale, it is called a crop. Most crops are cultivated in agriculture or hydroponic ...
of a heavy, undigested meal to take flight to flee from a potential predator. Its life expectancy in the wild ranges upward of 16 years, with a captive life span of over 45 years being possible.
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. While soaring, the turkey vulture holds its wings in a shallow V-shape
Many shapes have metaphorical names, i.e., their names are metaphors: these shapes are named after a most common object that has it. For example, "U-shape" is a shape that resembles the letter U, a bell-shaped curve has the shape of the vertical ...
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 thermal
A thermal column (or thermal) is a rising mass of buoyant air, a convective current in the atmosphere, that transfers heat energy vertically. Thermals are created by the uneven heating of Earth's surface from solar radiation, and are an example ...
s to stay soaring.[
]
Breeding
The breeding season of the turkey vulture varies according to latitude. In the southern United States, it commences in March, peaks in April to May, and continues into June. In more northerly latitudes, the season starts later and extends into August. 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.
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. Both parents incubate, and the young hatch after 30 to 40 days. Chicks are altricial
In biology, altricial species are those in which the young are underdeveloped at the time of birth, but with the aid of their parents mature after birth. Precocial species are those in which the young are relatively mature and mobile from the mome ...
, 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. If the chicks are threatened in the nest, they defend themselves by hissing and regurgitating. The young fledge at about nine to ten weeks. Family groups remain together until fall.
Feeding
The turkey vulture feeds primarily on a wide variety of carrion
Carrion () is the decaying flesh of dead animals, including human flesh.
Overview
Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters (or scavengers) include crows, vultures, c ...
, from small mammals to large grazers, preferring those recently dead, and avoiding carcasses that have reached the point of putrefaction
Putrefaction is the fifth stage of death, following pallor mortis, algor mortis, rigor mortis, and livor mortis. This process references the breaking down of a body of an animal, such as a human, post-mortem. In broad terms, it can be viewed ...
. They may rarely feed on plant matter, shoreline vegetation, pumpkin, coconut and other crops, live insects and other invertebrates
Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...
. In South America, turkey vultures have been photographed feeding on the fruits of the introduced oil palm
''Elaeis'' () is a genus of palms containing two species, called oil palms. They are used in commercial agriculture in the production of palm oil. The African oil palm ''Elaeis guineensis'' (the species name ''guineensis'' referring to its co ...
. They rarely, if ever, kill prey themselves; when they do it tends to comprise small weak offspring or very sick individuals of various animals, such as bird nestlings, as well as reptiles. Turkey vultures have also been observed eating coyote and domestic animal dung. The turkey vulture can often be seen along roadsides feeding on roadkill
Roadkill is an animal or animals that have been struck and killed by drivers of motor vehicles on highways. Wildlife-vehicle collisions (WVC) have increasingly been the topic of academic research to understand the causes, and how it can be mi ...
, or near bodies of water, feeding on washed-up fish. They also will feed on fish or insects that have become stranded in shallow water. Like other vultures, it plays an important role in the ecosystem
An ecosystem (or ecological system) consists of all the organisms and the physical environment with which they interact. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Energy enters the syste ...
by disposing of carrion, which would otherwise be a breeding ground for disease.
The turkey vulture forages by smell, an ability that is uncommon in the avian world, often flying low to the ground to pick up the scent of ethyl mercaptan
Ethanethiol, commonly known as ethyl mercaptan, is an organosulfur compound with the formula CH3CH2SH. is a colorless liquid with a distinct odor. Abbreviated EtSH, it consists of an ethyl group (Et), CH3CH2, attached to a thiol group, SH. Its st ...
, a gas produced by the beginnings of decay in dead animals. The olfactory lobe of its brain
A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a v ...
, responsible for processing smells, is particularly large compared to that of other animals. This heightened ability to detect odors allows it to search for carrion below the forest
A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...
canopy. King vulture
The king vulture (''Sarcoramphus papa'') is a large bird found in Central and South America. It is a member of the New World vulture family Cathartidae. This vulture lives predominantly in tropical lowland forests stretching from southern Mexic ...
s, black vultures, and condor
Condor is the common name for two species of New World vultures, each in a monotypic genus. The name derives from the Quechua ''kuntur''. They are the largest flying land birds in the Western Hemisphere.
They are:
* The Andean condor (''Vult ...
s, 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. It displaces the yellow-headed vultures from carcasses due to its larger size, but is displaced in turn by the king vulture and both types of condor, which make 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
Symbiosis (from Greek , , "living together", from , , "together", and , bíōsis, "living") is any type of a close and long-term biological interaction between two different biological organisms, be it mutualistic, commensalistic, or parasit ...
between species. Black vultures tend to be more aggressive and often displace turkey vultures which appear to be intimidated especially by the feeding frenzy
In ecology, a feeding frenzy occurs when predators are overwhelmed by the amount of prey available. The term is also used as an idiom in the English language.
Examples in nature
For example, a large school of fish can cause nearby sharks, such a ...
engaged in by the black vultures when they come in numbers (a behavior turkey vultures are apparently incapable of even when at a carcass in numbers), however pairs or individuals often seem to be able to peaceably share carrion with turkey vultures. However, in the tropics such as Peru, turkey vultures appeared to prevail regularly over black vultures, in 56% of cases, perhaps due to the smaller size of the region's black vultures.[Wallace, M. P., and S. A. Temple (1987). ''Competitive interactions within and between species in a guild of avian scavengers''. Auk 104:290–295.] It is further subservient to large hawks such as red-tailed hawk
The red-tailed hawk (''Buteo jamaicensis'') is a bird of prey that breeds throughout most of North America, from the interior of Alaska and northern Canada to as far south as Panama and the West Indies. It is one of the most common members with ...
s, Harris's hawk
The Harris's hawk (''Parabuteo unicinctus''), formerly known as the bay-winged hawk, dusky hawk, and sometimes a wolf hawk, and known in Latin America as peuco, is a medium-large bird of prey that breeds from the southwestern United States south ...
s and ''Buteogallus
''Buteogallus'' is a genus of birds of prey in the family Accipitridae. All members of this genus are essentially neotropical, but the distribution of a single species extends slightly into the extreme southwestern United States. Many of the sp ...
'' black hawks, as well as to large falcons like peregrine falcon
The peregrine falcon (''Falco peregrinus''), also known as the peregrine, and historically as the duck hawk in North America, is a Cosmopolitan distribution, cosmopolitan bird of prey (Bird of prey, raptor) in the family (biology), family Falco ...
s and crested caracara
The crested caracara (''Caracara plancus'') is a bird of prey in the family Falconidae. It is found from the southern United States through Central and South America to Tierra del Fuego. It was formerly placed in the genus ''Polyborus''.
Descri ...
s, despite most of these birds being rather smaller in body size than a turkey vulture. Often these raptors tend to engage in dive-bombing or other intimidation displays towards the vulture(s) to displace them from carrion or from perch sites. Presumably all sympatric eagle
Eagle is the common name for many large birds of prey of the family Accipitridae. Eagles belong to several groups of genera, some of which are closely related. Most of the 68 species of eagle are from Eurasia and Africa. Outside this area, just ...
s are also dominant, with bald eagle
The bald eagle (''Haliaeetus leucocephalus'') is a bird of prey found in North America. A sea eagle, it has two known subspecies and forms a species pair with the white-tailed eagle (''Haliaeetus albicilla''), which occupies the same niche as ...
s confirmed to easily dominate turkey vultures in Florida.[ However, in the tropics ]Swainson's hawk
Swainson's hawk (''Buteo swainsoni'') is a large bird species in the Accipitriformes order. This species was named after William Swainson, a British naturalist. It is colloquially known as the grasshopper hawk or locust hawk, as it is very fond ...
s and yellow-headed caracara
The yellow-headed caracara (''Daptrius chimachima'') is a bird of prey in the family Falconidae. It is found in tropical and subtropical South America and the southern portion of Central America. Unlike the falcons in the same family, the caraca ...
(as well as lesser yellow-headed vultures) appear to be subservient to turkey vultures.[ Furthermore, turkey vultures are dominant over ]crow
A crow is a bird of the genus ''Corvus'', or more broadly a synonym for all of ''Corvus''. Crows are generally black in colour. The word "crow" is used as part of the common name of many species. The related term "raven" is not pinned scientifical ...
s at carrion, but not over common raven
The common raven (''Corvus corax'') is a large all-black passerine bird. It is the most widely distributed of all corvids, found across the Northern Hemisphere. It is a raven known by many names at the subspecies level; there are at least e ...
s.
Relationship with humans
The turkey vulture is sometimes accused of carrying anthrax
Anthrax is an infection caused by the bacterium ''Bacillus anthracis''. It can occur in four forms: skin, lungs, intestinal, and injection. Symptom onset occurs between one day and more than two months after the infection is contracted. The sk ...
or hog cholera
Classical swine fever (CSF) or hog cholera (also sometimes called pig plague based on the German word ) is a highly contagious disease of swine (Old World and New World pigs). It has been mentioned as a potential bioweapon.
Clinical signs
Sw ...
, both livestock diseases, on its feet or bill by cattle ranchers and is therefore occasionally perceived as a threat.[ However, the virus that causes hog cholera is destroyed when it passes through the turkey vulture's digestive tract.] 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. The droppings produced by turkey vultures and other vultures can harm or kill trees and other vegetation. The turkey vulture can be held in captivity, though the Migratory Bird Treaty Act
The Migratory Bird Treaty Act of 1918 (MBTA), codified at (although §709 is omitted), is a United States federal law, first enacted in 1918 to implement the convention for the protection of migratory birds between the United States and Canada . ...
prevents this in the case of uninjured animals or animals capable of returning to the wild. In captivity, it can be fed fresh meat, and younger birds will gorge themselves if given the opportunity.
The turkey vulture species receives special legal protections under the Migratory Bird Treaty Act of 1918 in the United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...
, by the Convention for the Protection of Migratory Birds in Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...
, and by the Convention for the Protection of Migratory Birds and Game Mammals in Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
. In the US it is illegal to take, kill, or possess turkey vultures, their eggs, and any body parts including but not limited to their feathers; violation of the law is punishable by a fine of up to $100,000 for individuals or $200,000 for organizations, and/or a prison term of 1 year. It is listed as a species of least concern
A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. T ...
by the IUCN Red List
The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...
. 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 10 years or three generations.
References
Notes
Bibliography
* Ffrench, R. ''Birds of Trinidad and Tobago
Trinidad and Tobago (, ), officially the Republic of Trinidad and Tobago, is the southernmost island country in the Caribbean. Consisting of the main islands Trinidad and Tobago, and numerous much smaller islands, it is situated south of ...
''.
* Stiles and Skutch. ''A guide to the birds of Costa Rica''.
* Kirk, D. A. and M. J. Mossman. 1998. "Turkey Vulture (''Cathartes aura'')". In ''The Birds of North America'', No. 339 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia
Philadelphia, often called Philly, is the largest city in the Commonwealth of Pennsylvania, the sixth-largest city in the U.S., the second-largest city in both the Northeast megalopolis and Mid-Atlantic regions after New York City. Sinc ...
, PA.
External links
Turkey vultures
on eNature.com
*
Uncommon light morph turkey vulture photo
*
Live Streaming of a Vulture Feeding Station
at Selu Conservancy, Radford, Virginia.
{{Featured article
turkey vulture
The turkey vulture (''Cathartes aura'') is the most widespread of the New World vultures. One of three species in the genus ''Cathartes'' of the family Cathartidae, the turkey vulture ranges from southern Canada to the southernmost tip of South ...
Birds of prey of the Americas
turkey vulture
The turkey vulture (''Cathartes aura'') is the most widespread of the New World vultures. One of three species in the genus ''Cathartes'' of the family Cathartidae, the turkey vulture ranges from southern Canada to the southernmost tip of South ...
Taxa named by Carl Linnaeus
Extant Pleistocene first appearances