Bighorn Sheep

Species of sheep native to North America

This article is about the animal. For other uses, see Big Horn (disambiguation) .

Bighorn sheep

Temporal range: 0.7–0 Ma

PreꞒ

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Middle Pleistocene – recent

Male (ram), Wheeler Peak , New Mexico

Female (ewe), Greater Vancouver Zoo

Conservation status

Least Concern  (IUCN 3.1 ) [1]

CITES Appendix II [2] [note 1]

Scientific classification

Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Artiodactyla Family: Bovidae Subfamily: Caprinae Genus: Ovis Species: O. canadensis

Binomial name

Ovis canadensis Shaw , 1804

Bighorn sheep range [3] [4]

Synonyms

O. cervina Desmarest O. montana Cuvier [5]

The bighorn sheep (Ovis canadensis), or simply bighorn, is a species of mountain sheep indigenous to North America. It’s named, rather predictably, for its impressively large horns. A pair of these bony adornments can weigh up to a staggering 14 kg (30 lb), a considerable burden, especially when you consider the sheep itself typically tops out at around 143 kg (315 lb). Recent genetic analyses have illuminated a more nuanced picture of its lineage, revealing three distinct subspecies. Tragically, one of these, O. c. sierrae, is currently endangered, a grim testament to human impact.

These wild sheep are believed to have originally crossed into North America from Siberia, traversing the ancient Bering Land Bridge . At their peak, their numbers in North America were estimated to be in the millions, and they became deeply woven into the mythology and cultural fabric of Native Americans . However, by the dawn of the 20th century, their population had plummeted to mere thousands. This catastrophic decline was a brutal confluence of factors: diseases introduced by European livestock and the relentless pressure of overhunting.

Taxonomy and genetics

Ovis canadensis holds its place as one of the two species of wild mountain sheep found in North America, the other being its close relative, the Dall sheep (O. dalli). The ancestral wild sheep population is thought to have migrated across the Bering land bridge from Siberia into Alaska during the Pleistocene epoch, approximately 750,000 years ago. From this Alaskan foothold, they gradually dispersed throughout western North America, extending their range as far south as Baja California and into northwestern mainland Mexico. Genetic evidence suggests that the divergence from their closest Asian relatives, the snow sheep , occurred around 600,000 years ago. Within North America, this ancestral sheep population subsequently split into the two extant species we recognize today: the Dall sheep, which primarily inhabits Alaska and northwestern Canada, and the bighorn sheep, whose range sprawls from southwestern Canada down to Mexico. However, the distinctness of these species has been called into question by evidence of hybridization between them in their more recent evolutionary history, suggesting a more fluid genetic landscape than once assumed.

Former subspecies

The classification of bighorn sheep has been a dynamic field, with earlier attempts to delineate subspecies based primarily on morphology and geographic distribution. In 1940, Ian McTaggart-Cowan proposed a division of the species into seven subspecies. This classification distinguished between mountain bighorns and desert bighorns. The mountain bighorn subspecies he identified were:

• Rocky Mountain bighorn sheep (O. c. canadensis): Found across a broad swathe of territory, from British Columbia down to Arizona .
• †Badlands bighorn sheep (also known as Audubon’s bighorn sheep, O. c. auduboni): This subspecies was historically recorded in North Dakota, South Dakota, Montana, Wyoming, and Nebraska. Sadly, it has been recognized as extinct since 1925, a stark reminder of past conservation failures.
• California bighorn sheep (O. c. californiana): This subspecies was described as ranging from British Columbia southward into California , with its eastern extent reaching into North Dakota . It’s important to note that the definition and scope of this subspecies have been subject to revision based on later genetic studies, as discussed below.

The desert bighorn subspecies, as classified by Cowan, included:

• Desert bighorn sheep (O. c. nelsoni): This is the most commonly recognized desert bighorn subspecies, with a range encompassing much of California, Arizona, and parts of west Texas, the latter through dedicated conservation and re-introduction programs.
• Mexican bighorn sheep (O. c. mexicana): Found from Arizona and New Mexico extending south into the Mexican states of Sonora and Chihuahua .
• Peninsular bighorn sheep (O. c. cremnobates): Inhabiting the rugged Peninsular Ranges of California and Baja California , these sheep are adapted to a distinct arid environment.
• Weems’ bighorn sheep (O. c. weemsi): This subspecies is found in the southern reaches of Baja California.

Current subspecies

The landscape of bighorn sheep taxonomy has been significantly reshaped by advancements in genetic analysis. Beginning in 1993, research by Ramey and colleagues utilized DNA testing, revealing that the earlier seven-subspecies model was largely an oversimplification. The prevailing scientific consensus today recognizes three distinct subspecies of bighorn sheep. This modern taxonomy is strongly supported by comprehensive genetic studies, including a significant 2016 analysis that employed both microsatellite and mitochondrial DNA markers. This research identified substantial genetic divergence between the Rocky Mountain and Sierra Nevada bighorn sheep. Furthermore, it indicated that both of these lineages diverged from the desert bighorn lineage either during or prior to the Illinoian glaciation, approximately 315 to 94 thousand years ago. Consequently, the three currently recognized subspecies of O. canadensis are:

• Rocky Mountain bighorn sheep (O. c. canadensis): This subspecies occupies the majestic Rocky Mountains of both the United States and Canada, as well as the broader Northwestern United States region.
• Sierra Nevada bighorn sheep (O. c. sierrae): Formerly encompassed within the California bighorn sheep designation, this is a genetically distinct subspecies now recognized as occurring exclusively in the Sierra Nevada mountain range of California . Historical records, however, suggest that bighorn sheep may have once ranged further west, into the California Coastal Ranges , which are geographically connected to the Sierra Nevada via the Transverse Ranges . Accounts from the late 18th century describe “wild sheep” in the vicinity of the Mission San Antonio near Jolon, California , and in the mountains surrounding San Francisco Bay , hinting at a more extensive historical distribution.
• Desert bighorn sheep (O. c. nelsoni): This subspecies is found throughout the arid desert regions of the Southwestern United States and extends into northwestern Mexico. The 2016 genetic study further refined our understanding of desert bighorn diversity, suggesting the existence of three distinct lineages within this subspecies. These lineages align with the earlier classifications of Nelson’s (O. c. nelsoni), Mexican (O. c. mexicana), and Peninsular (O. c. cremnobates). The habitats occupied by these three lineages present significant climatic variations, implying that they have been subjected to different environmental pressures and selection regimes.

In addition to these subspecies, two specific populations are currently designated as endangered by the United States government: the Sierra Nevada bighorn sheep (O. c. sierrae) and the Peninsular bighorn sheep, which is recognized as a distinct population segment within the desert bighorn sheep (O. c. nelsoni).

Description

A juvenile (lamb)

The defining characteristic of the bighorn sheep, and the source of its common name, are the large, spiraling horns that adorn the heads of rams (males). While ewes (females) also possess horns, they are considerably smaller, more delicate, and less dramatically curved. The sheep’s coat varies in coloration, ranging from a light brown to a grayish hue, or sometimes a deep, chocolate brown. A distinctive white patch marks their rump, and this same coloration extends down the back of all four legs.

Males typically exhibit a robust build, weighing between 58–143 kg (128–315 lb). They stand 90–105 cm (35–41 in) tall at the shoulder and measure 1.6–1.85 m (63–73 in) in length from the tip of their nose to the base of their tail. Females are generally more slender, weighing between 34–91 kg (75–201 lb), with a shoulder height of 75–90 cm (30–35 in) and a body length of 1.28–1.58 m (50–62 in). The rams’ cranial structure is particularly noteworthy, featuring large horn cores, enlarged cornual and frontal sinuses, and internal bony septa . These specialized anatomical features are crucial adaptations that protect the brain by effectively absorbing the immense impact generated during the violent clashes that characterize their sparring behavior.

Bighorn sheep also possess specialized scent glands. They have preorbital glands located at the front corner of each eye, inguinal glands situated in the groin area, and pedal glands found on each foot. The secretions from these glands are believed to play a role in communication and may support social and dominance behaviors within the herd.

There’s a noticeable size difference between subspecies. Bighorns from the Rocky Mountains tend to be larger, with males occasionally exceeding 230 kg (500 lb) and females surpassing 90 kg (200 lb). In stark contrast, males of the Sierra Nevada bighorn subspecies typically weigh no more than 90 kg (198 lb), with females reaching up to 60 kg (132 lb). The sheer weight of a ram’s horns alone can be substantial, reaching up to 14 kg (30 lb), which is comparable to the weight of all the other bones in the male’s body combined.

Natural history

Ecology

Bighorn rams

A bighorn ram near Jasper, Alberta

The ecological niches occupied by bighorn sheep differ significantly based on their subspecies. The Rocky Mountain and Sierra Nevada bighorn sheep are adapted to the cooler, mountainous environments of Canada and the United States. In contrast, the desert bighorn sheep subspecies are uniquely suited to the harsh, arid desert ecosystems found in the Southwestern United States and Mexico. Bighorn sheep, in general, prefer habitats characterized by alpine meadows, grassy mountain slopes, and foothill terrains that are in close proximity to rugged, rocky cliffs and bluffs. These steep, broken landscapes provide essential escape routes and protection from predators.

A critical environmental factor influencing their distribution is snowfall. Bighorn sheep are not well-equipped to navigate deep snow, making them susceptible to harsh winter conditions. Consequently, they tend to inhabit areas where annual snowfall is less than approximately 150 cm (60 in) per year. Their seasonal movements often involve migrating to lower elevations for winter and ascending to higher elevations for the summer months, a pattern dictated by resource availability and snowpack depth.

Bighorn sheep are notoriously vulnerable to certain diseases that are prevalent in domestic sheep, most notably psoroptic scabies and pneumonia . Beyond disease, mortality can also result from unfortunate accidents, such as rockfalls or accidental falls from the treacherous cliffs that define their habitat. Despite the inherent dangers of their environment, bighorns are exceptionally adept climbers, utilizing their agility to ascend steep terrain where they can seek refuge from predators. The youngest members of the population, the lambs, are the most vulnerable to predation. A wide array of predators pose a threat, including coyotes , bobcats , gray foxes , wolverines , jaguars , ocelots , lynxes , and golden eagles .

Larger predators like black bears , grizzly bears , wolves , and particularly mountain lions present a significant threat to bighorn sheep of all ages. Mountain lions, with their exceptional agility, are perhaps the most formidable predators in the rocky, uneven terrain favored by bighorns. It’s also worth noting that human-induced changes to the environment, such as wildfire suppression techniques, can inadvertently create denser shrublands. This increased cover can subsequently elevate predation rates by mountain lions, as it provides them with more advantageous hunting grounds.

Bighorn sheep are often considered valuable indicators of land health. Their sensitivity to various environmental disturbances, particularly those caused by human activities, makes their population status a barometer for the overall well-being of their ecosystems. Beyond their ecological significance, bighorn sheep are highly prized by hunters for their challenging pursuit and the trophy quality of their horns, contributing to their desirability as game animals.

Their diet primarily consists of grasses and they browse on shrubs , especially during the fall and winter months. They also exhibit a strong inclination to seek out minerals at natural salt licks , which are vital for their nutritional needs. Behavioral observations suggest a difference in foraging strategies between sexes: females tend to forage and move frequently, a behavior likely linked to predator avoidance and the protection of their lambs. Males, on the other hand, tend to graze and then rest to ruminate. This pattern in males may contribute to more efficient digestion and facilitate greater increases in body size.

Social structure and reproduction

Bighorn sheep are gregarious animals, typically living in herds. Unlike the mouflon – the ancestor of domestic sheep – which exhibits a strict dominance hierarchy with a clear single leader ram, bighorn sheep herds do not generally adhere to such rigid structures. However, prior to the onset of the mating season, or “rut ”, rams do engage in behaviors aimed at establishing a dominance hierarchy. This hierarchy primarily determines which rams gain preferential access to ewes for mating. Much of the characteristic head-butting, or horn clashing, occurs during this pre-rut period, although some level of this aggressive display can be observed throughout the year.

The agonistic behavior displayed by bighorn rams is quite distinctive: two rivals will often walk away from each other, then turn and charge, colliding head-on with immense force. The tips of rams’ horns are frequently “broomed,” meaning they are worn down or broken off. This is a natural consequence of the intense and frequent sparring that occurs between males competing for mating rights. In contrast, females exhibit a more stable, non-linear social hierarchy that is strongly correlated with age. Young females may engage in conflicts to secure a high social status when they are integrated into the herd’s hierarchy, typically between one and two years of age.

• Rams butting heads, in California

• Horns through ontogeny

Rocky Mountain bighorn rams employ a variety of courting strategies to secure mating opportunities. The most prevalent and generally successful strategy is the “tending” approach, where a ram closely follows and actively defends a receptive, estrous ewe. This strategy demands significant physical stamina and constant vigilance from the ram, and ewes appear to favor males exhibiting this behavior, likely perceiving them as the most fit. Another tactic is “coursing,” which involves rams fighting amongst themselves for possession of a ewe that is already being tended by another male. However, ewes typically avoid males engaged in coursing, rendering this strategy largely ineffective. A third strategy is “blocking,” where rams attempt to prevent a ewe from accessing tending areas even before she enters estrus.

15 year old bighorn ram, in Alberta. Nicknamed the “King of Waterton”, he died shortly after this photo was taken. [34]

Bighorn ewes have a gestation period lasting approximately six months. In temperate regions, the peak of the rut usually occurs in November, leading to the birth of one, or occasionally two, lambs in May. The majority of births tend to happen within the first two weeks of the lambing season. Pregnant ewes in the Rocky Mountains often undertake migrations to higher alpine areas in the spring. This behavior is thought to be an adaptation to find safer birthing grounds, away from the higher concentration of predators found at lower elevations. However, these alpine areas may not offer the same quality of forage as lower meadows. Lambs born earlier in the season generally have a higher probability of survival compared to those born later. This is partly because lambs born later may not receive sufficient milk, as their mothers’ lactation period coincides with a decline in food quality. Newborn lambs typically weigh between 3.6 and 4.5 kg (8 to 10 lb) and are remarkably capable of walking within a few hours of birth. Weaning usually occurs when the lambs reach four to six months of age. The average lifespan for ewes is typically 10–14 years, while rams generally live for 9–12 years.

Infectious disease

A significant threat to many bighorn sheep populations across the United States is the recurring outbreak of infectious pneumonia . [37] [38] [39] [40] These devastating die-offs are strongly linked to the introduction of bacterial pathogens, particularly Mycoplasma ovipneumoniae [41] [42] and certain strains of Mannheimia haemolytica , [43] which are often carried asymptomatically by domestic sheep. [44] Once these pathogens enter a bighorn population, they can spread with alarming rapidity, leading to widespread mortality that can decimate up to 90% of the affected population. In the years immediately following the introduction of these pathogens, bighorn populations frequently experience persistent outbreaks of lamb pneumonia. These recurrent outbreaks severely hinder lamb survival and reproductive recruitment , playing a critical role in suppressing overall population growth.

Relationship with humans

Conservation

Bighorn ram skull

Two centuries ago, bighorn sheep were a common sight throughout the western United States, Canada, and northern Mexico. Their population was estimated to be between 150,000 and 200,000 individuals. [45] [46] A confluence of factors led to their dramatic decline, with the most severe reduction occurring between roughly 1870 and 1950. These contributing factors included unregulated hunting, extensive habitat destruction, overgrazing of vital rangelands by domestic livestock, and the transmission of diseases from these domestic animals.

In 1936, the Arizona Boy Scouts initiated a statewide campaign dedicated to the conservation of the bighorn sheep. Their involvement was sparked by the efforts of Major Frederick Russell Burnham , who had observed that fewer than 150 bighorn sheep remained in the Arizona mountains. This conservation movement gained further momentum with the support of organizations such as the National Wildlife Federation , the Izaak Walton League , and the National Audubon Society . [49] A significant conservation achievement was the establishment of over 600,000 hectares (1,500,000 acres) of protected land on January 18, 1939, through the creation of the Kofa National Wildlife Refuge and the Cabeza Prieta National Wildlife Refuge . [49]

Since the 1940s, numerous state and federal agencies have been actively involved in bighorn sheep restoration efforts. Despite these dedicated endeavors, the success has been limited, and a significant portion of the bighorn sheep’s historical range remains unoccupied. Hunting of male bighorn sheep is permitted in both Canada and the United States, but it is strictly regulated. [1]

In culture

A petroglyph of a caravan of bighorn sheep near Moab, Utah , United States, a common theme in glyphs from the desert southwest

The bighorn sheep held a place of deep admiration among the Apsaalooka (Crow) people. The mountain range now known as the Bighorn Mountains was a central part of their ancestral lands. Within the Bighorn Canyon National Recreation Area book, a traditional story told by Old Coyote recounts a legend involving the bighorn sheep. The tale describes a man possessed by malevolent spirits who attempts to kill his heir by pushing him off a cliff. The young man survives, caught in the branches of trees, and is subsequently rescued by bighorn sheep. Taking the name of their leader, Big Metal, the man is granted the sheep’s powers: wisdom, keen eyesight, sure-footedness, sharp hearing, immense strength, and a resilient heart. Big Metal returns to his people with a crucial message: the Apsaalooka nation will endure only as long as the river flowing from the mountains is known as the Bighorn River. [50]

Bighorn sheep are hunted for their meat and horns, which are utilized in various ceremonies, as a food source, and as hunting trophies. They also contribute to the local economies through ecotourism , drawing visitors who wish to observe these magnificent animals in their natural habitat. [51]

The Rocky Mountain bighorn sheep is recognized as the provincial mammal of Alberta and serves as the state animal for both Colorado and Nevada . Its image is incorporated into the symbol for the Colorado Division of Parks and Wildlife. [52] The Desert bighorn sheep holds the distinction of being the state mammal of [Nevada]. [53]

The bighorn sheep was famously featured in the 1967 children’s book Buford the Little Bighorn by Bill Peet . The protagonist, Buford, is characterized by his exceptionally large horns, a feature that mirrors the distinctive appearance of Rudolph the Red-Nosed Reindeer .

Historically, bighorn sheep were sometimes known by the scientific identification “argali” or “argalia.” This nomenclature arose from an initial assumption that they were the same species as the Asiatic argali (Ovis ammon). [54] The journals of the Lewis and Clark Expedition document numerous sightings of O. canadensis, with the explorers occasionally using the name “argalia.” They also recorded the use of bighorn sheep horns by the Shoshone people in the construction of composite bows. [55] A map produced by William Clark after the expedition in 1814, titled “A Map of Lewis and Clark’s track across the western portion of North America,” indicated a tributary of the Yellowstone River named Argalia Creek and another tributary of the Missouri River named Argalia River, both located in present-day Montana . Neither of these tributaries retained these names. However, the Bighorn River , another tributary of the Yellowstone, and its own tributary, the Little Bighorn River , were also marked on Clark’s map and have retained their names. The latter is notably the namesake of the historic [Battle of the Little Bighorn]. [56]

The Bighorn Ram was also depicted in a series of prints by the renowned artist Andy Warhol . In 1983, Warhol was commissioned to create a portfolio of ten endangered species to raise environmental awareness. This portfolio, known as “Endangered Species,” was produced in support of the Endangered Species Act , legislation enacted by the U.S. Congress in 1973. Other animals featured in this collection included the Siberian Tiger , Bald Eagle , and the Giant Panda . [57]

Notes

• Only the population of Mexico.

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• This article incorporates public domain material from Singer, Francis (1995). “Bighorn Sheep in the Rocky Mountain National Parks” (PDF). In Stohlgren, T.J. (ed.). The Interior West. In: Our Living Resources: A Report to the Nation on the Distribution, Abundance, and Health of U.S. Plants, Animals, and Ecosystems. Washington, D.C.: U.S. Geological Survey. Archived from the original (PDF) on 2007-10-31.
• van Wyk, Peter (2000). Burnham: King of Scouts. Trafford Publishing. ISBN 978-1-4122-0028-8. Retrieved 2007-03-30.
• a b Edward H. Saxton (March 1978). “Saving the Desert Bighorns”. Desert Magazine. 41 (3). Retrieved 2008-04-27.
• a b Graetz, Rick; Susie Graetz. “About the Crow: Introduction”. Little Big Horn College Library. Archived from the original on 2011-06-14. Retrieved 2010-03-21.
• “Glacier National Park Vacation Planner” (PDF). nps.gov. National Park Service. Archived from the original (PDF) on 2013-03-19. Retrieved 15 October 2015.
• “Colorado State Symbols”. Archived from the original on 8 July 2007. Retrieved 2007-07-25.
• “Nevada Facts and State Emblems”. Nevada State Legislature. Retrieved 2021-09-10.
• Stewart, George R. Jr. (December 1935). “Popular Names of the Mountain Sheep”. American Speech. 10 (4). Duke University Press: 283–288. doi :10.2307/451603. JSTOR 451603.
• Tubbs, Stephenie Ambrose; Jenkinson, Clay Straus (2003). The Lewis and Clark Companion: An Encyclopedia Guide to the Voyage of Discovery. Henry Holt and Company. pp. 12–13. ISBN 978-0-8050-6726-2.
• Lewis, Samuel; William Clark (1814). “A Map of Lewis and Clark’s track across the western portion of North America, from the Mississippi to the Pacific Ocean”. Longman, Hurst, Reese, Orme and Brown. Retrieved 2007-03-11.
• “Andy Warhol Endangered Species Portfolio About”. Andipa Editions. Retrieved 2023-08-22.

External links

• Wikimedia Commons has media related to: Ovis canadensis (category)

• Photos & Information on Wild Rocky Mountain Bighorn Sheep in Nevada

• BIGHORN.org

• Rocky Mountain bighorn research

• Greater Yellowstone Resource Guide – Bighorn Sheep

• Desert Bighorn Sheep Facts Archived 2012-09-26 at the Wayback Machine California Department of Fish and Game

• Smithsonian Museum of Natural History: Ovis canadensis

• v

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Extant Artiodactyla species

• Kingdom: Animalia
• Phylum: Chordata
• Class: Mammalia
• Infraclass: Eutheria
• Superorder: Laurasiatheria

Suborder Ruminantia

• Antilocapridae
  • Antilocapra
    • Pronghorn (A. americana)
• Giraffidae
  • Okapia
    • Okapi (O. johnstoni)
  • Giraffa
    • Northern giraffe (G. camelopardalis)
    • Southern giraffe (G. giraffa)
    • Reticulated giraffe (G. reticulata)
    • Masai giraffe (G. tippelskirchi)
• Moschidae
  • Moschus
    • Anhui musk deer (M. anhuiensis)
    • Dwarf musk deer (M. berezovskii)
    • Alpine musk deer (M. chrysogaster)
    • Kashmir musk deer (M. cupreus)
    • Black musk deer (M. fuscus)
    • Himalayan musk deer (M. leucogaster)
    • Siberian musk deer (M. moschiferus)
• Tragulidae
  • Hyemoschus
    • Water chevrotain (H. aquaticus)
  • Moschiola
    • Indian spotted chevrotain (M. indica)
    • Yellow-striped chevrotain (M. kathygre)
    • Sri Lankan spotted chevrotain (M. meminna)
  • Tragulus
    • Java mouse-deer (T. javanicus)
    • Lesser mouse-deer (T. kanchil)
    • Greater mouse-deer (T. napu)
    • Philippine mouse-deer (T. nigricans)
    • Vietnam mouse-deer (T. versicolor)
    • Williamson’s mouse-deer (T. williamsoni)
• Cervidae
  • Large family listed below
• Bovidae
  • Large family listed below

Family Cervidae

• Cervinae
  • Muntiacus
    • Bornean yellow muntjac (M. atherodes)
    • Hairy-fronted muntjac (M. crinifrons)
    • Fea’s muntjac (M. feae)
    • Gongshan muntjac (M. gongshanensis)
    • Sumatran muntjac (M. montanus)
    • Southern red muntjac (M. muntjak)
    • Pu Hoat muntjac (M. puhoatensis)
    • Leaf muntjac (M. putaoensis)
    • Reeves’s muntjac (M. reevesi)
    • Roosevelt’s muntjac (M. rooseveltorum)
    • Truong Son muntjac (M. truongsonensis)
    • Northern red muntjac (M. vaginalis)
    • Giant muntjac (M. vuquangensis)
  • Elaphodus
    • Tufted deer (E. cephalophus)
  • Dama
    • European fallow deer (D. dama)
    • Persian fallow deer (D. mesopotamica)
  • Axis
    • Chital (A. axis)
    • Calamian deer (A. calamianensis)
    • Bawean deer (A. kuhlii)
    • Hog deer (A. porcinus)
  • Rucervus
    • Barasingha (R. duvaucelii)
    • Eld’s deer (R. eldii)
  • Elaphurus
    • Père David’s deer (E. davidianus)
  • Rusa
    • Visayan spotted deer (R. alfredi)
    • Philippine sambar (R. mariannus)
    • Rusa deer (R. timorensis)
    • Sambar (R. unicolor)
  • Cervus
    • Thorold’s deer (C. albirostris)
    • Red deer (C. elaphus)
    • Elk (C. canadensis)
    • Central Asian red deer (C. hanglu)
    • Sika deer (C. nippon)
• Capreolinae
  • Alces
    • Moose (A. alces)
  • Hydropotes
    • Water deer (H. inermis)
  • Capreolus
    • European roe deer (C. capreolus)
    • Siberian roe deer (C. pygargus)
  • Rangifer
    • Reindeer (R. tarandus)
  • Hippocamelus
    • Taruca (H. antisensis)
    • South Andean deer (H. bisulcus)
  • Mazama
    • Red brocket (M. americana)
    • Small red brocket (M. bororo)
    • Merida brocket (M. bricenii)
    • Dwarf brocket (M. chunyi)
    • Pygmy brocket (M. nana)
    • Amazonian brown brocket (M. nemorivaga)
    • Little red brocket (M. rufina)
    • Central American red brocket (M. temama)
  • Ozotoceros
    • Pampas deer (O. bezoarticus)
  • Blastocerus
    • Marsh deer (B. dichotomus)
  • Pudu
    • Northern pudu (P. mephistophiles) ?
    • Southern pudu (P. pudu)
  • Pudella
    • Peruvian Yungas pudu (P. carlae)
    • Northern pudu (P. mephistophiles)
  • Odocoileus
    • Mule deer (O. hemionus)
    • Yucatan brown brocket (O. pandora)
    • White-tailed deer (O. virginianus)
  • Subulo
    • Gray brocket (S. gouazoubira)

Family Bovidae

• Hippotraginae
  • Hippotragus
    • Roan antelope (H. equinus)
    • Sable antelope (H. niger)
  • Oryx
    • East African oryx (O. beisa)
    • Scimitar oryx (O. dammah)
    • Gemsbok (O. gazella)
    • Arabian oryx (O. leucoryx)
  • Addax
    • Addax (A. nasomaculatus)
• Reduncinae
  • Kobus
    • Waterbuck (K. ellipsiprymnus)
    • Kob (K. kob)
    • Lechwe (K. leche)
    • Nile lechwe (K. megaceros)
    • Puku (K. vardonii)
  • Redunca
    • Southern reedbuck (R. arundinum)
    • Mountain reedbuck (R. fulvorufula)
    • Bohor reedbuck (R. redunca)
• Aepycerotinae
  • Aepyceros
    • Impala (A. melampus)
• Peleinae
  • Pelea
    • Grey rhebok (P. capreolus)
• Alcelaphinae
  • Beatragus
    • Hirola (B. hunteri)
  • Damaliscus
    • Common tsessebe (D. lunatus)
    • Bontebok (D. pygargus)
  • Alcelaphus
    • Hartebeest (A. buselaphus)
  • Connochaetes
    • Black wildebeest (C. gnou)
    • Blue wildebeest (C. taurinus)
• Pantholopinae
  • Pantholops
    • Tibetan antelope (P. hodgsonii)
• Caprinae
  • Large subfamily listed below
• Bovinae
  • Large subfamily listed below
• Antilopinae
  • Large subfamily listed below

Family Bovidae (subfamily Caprinae )

• Ammotragus
  • Barbary sheep (A. lervia)
• Arabitragus
  • Arabian tahr (A. jayakari)
• Budorcas
  • Takin (B. taxicolor)
• Capra
  • Wild goat (C. aegagrus)
  • West Caucasian tur (C. caucasia)
  • East Caucasian tur (C. cylindricornis)
  • Markhor (C. falconeri)
  • Domestic goat (C. hircus)
  • Alpine ibex (C. ibex)
  • Nubian ibex (C. nubiana)
  • Iberian ibex (C. pyrenaica)
  • Siberian ibex (C. sibirica)
  • Walia ibex (C. walie)
• Capricornis
  • Japanese serow (C. crispus)
  • Red serow (C. rubidus)
  • Mainland serow (C. sumatraensis)
  • Taiwan serow (C. swinhoei)
• Hemitragus
  • Himalayan tahr (H. jemlahicus)
• Naemorhedus
  • Red goral (N. baileyi)
  • Long-tailed goral (N. caudatus)
  • Himalayan goral (N. goral)
  • Chinese goral (N. griseus)
• Oreamnos
  • Mountain goat (O. americanus)
• Ovibos
  • Muskox (O. moschatus)
• Nilgiritragus
  • Nilgiri tahr (N. hylocrius)
• Ovis
  • Argali (O. ammon)
  • Domestic sheep (O. aries)
  • Bighorn sheep (O. canadensis)
  • Dall sheep (O. dalli)
  • Mouflon (O. gmelini)
  • Snow sheep (O. nivicola)
  • Urial (O. vignei)
• Pseudois
  • Bharal (P. nayaur)
• Rupicapra
  • Pyrenean chamois (R. pyrenaica)
  • Chamois (R. rupicapra)

Family Bovidae (subfamily Bovinae )

• Boselaphini
  • Tetracerus
    • Four-horned antelope (T. quadricornis)
  • Boselaphus
    • Nilgai (B. tragocamelus)
• Bovini
  • Bubalus
    • Wild water buffalo (B. arnee)
    • Domestic water buffalo (B. bubalis)
    • Lowland anoa (B. depressicornis)
    • Tamaraw (B. mindorensis)
    • Mountain anoa (B. quarlesi)
  • Bos
    • American bison (B. bison)
    • European bison (B. bonasus)
    • Bali cattle (B. domesticus)
    • Gayal (B. frontalis)
    • Gaur (B. gaurus)
    • Domestic yak (B. grunniens)
    • Zebu (B. indicus)
    • Banteng (B. javanicus)
    • Wild yak (B. mutus)
    • Cattle (B. taurus)
  • Pseudoryx
    • Saola (P. nghetinhensis)
  • Syncerus
    • African buffalo (S. caffer)
• Tragelaphini
  • Tragelaphus (including kudus )
    • Nyala (T. angasii)
    • Mountain nyala (T. buxtoni)
    • Bongo (T. eurycerus)
    • Lesser kudu (T. imberbis)
    • Harnessed bushbuck (T. scriptus)
    • Sitatunga (T. spekeii)
    • Greater kudu (T. strepsiceros)
    • Cape bushbuck (T. sylvaticus)
  • Taurotragus
    • Giant eland (T. derbianus)
    • Common eland (T. oryx)

Family Bovidae (subfamily Antilopinae )

• Antilopini
  • Ammodorcas
    • Dibatag (A. clarkei)
  • Antidorcas
    • Springbok (A. marsupialis)
  • Antilope
    • Blackbuck (A. cervicapra)
  • Eudorcas
    • Mongalla gazelle (E. albonotata)
    • Red-fronted gazelle (E. rufifrons)
    • Thomson’s gazelle (E. thomsonii)
    • Heuglin’s gazelle (E. tilonura)
  • Gazella
    • Arabian gazelle (G. arabica)
    • Chinkara (G. bennettii)
    • Cuvier’s gazelle (G. cuvieri)
    • Dorcas gazelle (G. dorcas)
    • Mountain gazelle (G. gazella)
    • Rhim gazelle (G. leptoceros)
    • Speke’s gazelle (G. spekei)
    • Goitered gazelle (G. subgutturosa)
  • Litocranius
    • Gerenuk (L. walleri)
  • Nanger
    • Dama gazelle (N. dama)
    • Grant’s gazelle (N. granti)
    • Bright’s gazelle (N. notatus)
    • Peter’s gazelle (N. petersii)
    • Soemmerring’s gazelle (N. soemmerringii)
  • Procapra
    • Mongolian gazelle (P. gutturosa)
    • Goa (P. picticaudata)
    • Przewalski’s gazelle (P. przewalskii)
• Saigini
  • Saiga
    • Saiga antelope (S. tatarica)
• Neotragini
  • Dorcatragus
    • Beira (D. megalotis)
  • Madoqua
    • Günther’s dik-dik (M. guentheri)
    • Kirk’s dik-dik (M. kirkii)
    • Silver dik-dik (M. piacentinii)
    • Salt’s dik-dik (M. saltiana)
  • Neotragus
    • Royal antelope (N. pygmaeus)
  • Nesotragus
    • Bates’ pygmy antelope (N. batesi)
    • Suni (N. moschatus)
  • Oreotragus
    • Klipspringer (O. oreotragus)
  • Ourebia
    • Oribi (O. ourebi)
  • Raphicerus
    • Steenbok (R. campestris)
    • Cape grysbok (R. melanotis)
    • Sharpe’s grysbok (R. sharpei)
• Cephalophini
  • Cephalophus
    • Aders’s duiker (C. adersi)
    • Brooke’s duiker (C. brookei)
    • Peters’ duiker (C. callipygus)
    • White-legged duiker (C. crusalbum)
    • Bay duiker (C. dorsalis)
    • Harvey’s duiker (C. harveyi)
    • Jentink’s duiker (C. jentinki)
    • White-bellied duiker (C. leucogaster)
    • Red forest duiker (C. natalensis)
    • Black duiker (C. niger)
    • Black-fronted duiker (C. nigrifrons)
    • Ogilby’s duiker (C. ogilbyi)
    • Ruwenzori duiker (C. rubidis)
    • Red-flanked duiker (C. rufilatus)
    • Yellow-backed duiker (C. silvicultor)
    • Abbott’s duiker (C. spadix)
    • Weyns’s duiker (C. weynsi)
    • Zebra duiker (C. zebra)
  • Philantomba
    • Blue duiker (P. monticola)
    • Maxwell’s duiker (P. maxwellii)
    • Walter’s duiker (P. walteri)
  • Sylvicapra
    • Common duiker (S. grimmia)

Suborder Suina

• Suidae
  • Babyrousa
    • Buru babirusa (B. babyrussa)
    • North Sulawesi babirusa (B. celebensis)
    • Togian babirusa (B. togeanensis)
  • Hylochoerus
    • Giant forest hog (H. meinertzhageni)
  • Phacochoerus
    • Desert warthog (P. aethiopicus)
    • Common warthog (P. africanus)
  • Porcula
    • Pygmy hog (P. salvania)
  • Potamochoerus
    • Bushpig (P. larvatus)
    • Red river hog (P. porcus)
  • Sus
    • Palawan bearded pig (S. ahoenobarbus)
    • Bornean bearded pig (S. barbatus)
    • Visayan warty pig (S. cebifrons)
    • Celebes warty pig (S. celebensis)
    • Domestic pig (S. domesticus)
    • Flores warty pig (S. heureni)
    • Oliver’s warty pig (S. oliveri)
    • Philippine warty pig (S. philippensis)
    • Wild boar (S. scrofa)
    • Timor warty pig (S. timoriensis)
    • Javan warty pig (S. verrucosus)
• Tayassuidae
  • Tayassu
    • White-lipped peccary (T. pecari)
  • Catagonus
    • Chacoan peccary (C. wagneri)
  • Dicotyles
    • Collared peccary (D. tajacu)

Suborder Tylopoda

• Camelidae
  • Lama
    • Llama (L. glama)
    • Guanaco (L. guanicoe)
    • Alpaca (L. pacos)
    • Vicuña (L. vicugna)
  • Camelus
    • Domestic Bactrian camel (C. bactrianus)
    • Dromedary/Arabian camel (C. dromedarius)
    • Wild Bactrian camel (C. ferus)

Suborder Whippomorpha

• Hippopotamidae

  • Hippopotamus
    • Hippopotamus (H. amphibius)
  • Choeropsis
    • Pygmy hippopotamus (C. liberiensis)

• Cetacea

  • see Cetacea

• Authority control databases

  • National
    • Japan
    • Israel
  • Other
    • NARA
    • Yale LUX

• Taxon identifiers

  • Ovis canadensis
    • Wikidata : Q189466
    • Wikispecies : Ovis canadensis
    • ADW : Ovis_canadensis
    • BioLib: 33770
    • BOLD : 12419
    • CoL : 4B9VG
    • EoL : 328658
    • EPPO : OVISCA
    • FEIS: ovca
    • GBIF : 2441119
    • iNaturalist : 42391
    • IRMNG : 10197226
    • ITIS : 180711
    • IUCN : 15735
    • MDD : 1006205
    • MSW : 14200835
    • NatureServe : 2.102557
    • NCBI : 37174
    • Observation.org : 79946
    • Open Tree of Life : 123206
    • Paleobiology Database : 49517
    • Species+ : 3036
    • Xeno-canto : Ovis-canadensis