Hemitragus jayakariArabian tahr

Geographic Range

Arabian tahrs are currently found in the Hajar Mountains of the United Arab Emirates and the northern parts of Oman. The current known range is 8,863 square kilometers, and the total possible range is 15,787 square kilometers. (Insall, 2008; Robinson, 2005)

Habitat

Arabian tahrs have a limited range geographically and are possibly extinct in the United Arab Emirates. They inhabit north slopes of the Hajar Mountains and Musandan masifs, where they persist on steep ground. Tahrs occupy the relatively rainy slopes of these mountains which contain enough water and diverse vegetation for them to survive. At the bottoms of these mountains, water sources in valleys, called wadis, are important for the survival of Arabian tahrs. (Insall, 2008; Robinson, 2005; "ARKive: Images of Life on Earth", 2009a)

  • Range elevation
    1000 to 1800 m
    3280.84 to 5905.51 ft
  • Average elevation
    1200 m
    3937.01 ft

Physical Description

Hemitragus jayakari the smallest tahr species. Both sexes possess horns pointing backwards, although the horns of males are larger and more dense than those of females. The hair is long and reddish with a dark brown stripe running down the back from the head to the tail. Males grow noticeable manes every year along their backs and have impressive, long hair on their chins and chests and extending to their front legs, that can grow quite long. Their hooves are supple and provide traction in their mountainous terrain. Males weigh approximately 40 kg and females weigh 17 to 20 kg. They are 59.7 to 63.5 cm height at the shoulder, compared to Himalayan tahrs and Nilgiri tahrs (both around 101.6 cm). (Insall, 2008; Robinson, 2005; "ARKive: Images of Life on Earth", 2009a)

  • Range mass
    17 to 40 kg
    37.44 to 88.11 lb

Reproduction

Arabian tahrs seem to be monogamous, with most observations being of a single male with a single female in the male's territory. They are unusual among bovids in defending territories. Males use their urine to mark their territory and their mates. Their horns are used in male-male combat over females. (Burton and Burton, 2002; Robinson, 2005)

It is interesting that Himalayan tahr and Nilgiri tahr are polygamous and Hemitragus jayakari is only polygamous in captivity. Perhaps the decline of resources, habitat destruction, and their resultant rarity prevents Arabian tahrs from being polygamous or forming large groups in the wild. (Insall, 2008; Robinson, 2005; "ARKive: Images of Life on Earth", 2009a)

Breeding in Arabian tahrs occurs year-round and is opportunistic. They find a mate and form small exclusive groups of two to four related individuals. They do not form rutting herds. Copulation occurs year round, but optimum breeding is in the months of November and December. When resources are abundant, it is common for females to give birth to up to two offspring. Gestation is for 140 to 145 days, leading to peak birthing in March and April. Young Arabian tahrs may not breed until they are 2 to 3 years old. (Insall, 2008; Robinson, 2005; "ARKive: Images of Life on Earth", 2009a)

  • Breeding interval
    Arabian tahrs breed year-round, with breeding peaking in November and December.
  • Breeding season
    November and December
  • Range number of offspring
    1 to 2
  • Average number of offspring
    1
  • Range gestation period
    140 to 145 days
  • Average gestation period
    140 days
  • Range time to independence
    2 to 3 years
  • Average time to independence
    2 years
  • Range age at sexual or reproductive maturity (female)
    2 to 3 years
  • Range age at sexual or reproductive maturity (male)
    2 to 3 years

Arabian tahr females gestate, nurse, and protect their young until independence. Males may contribute through defending territories with good resources and helping to defend the young, although there are few observations in the wild. Arabian tahr young remain with their mother or with the male and female parents for 2 to 3 years before becoming independent. (Robinson, 2005; "ARKive: Images of Life on Earth", 2009a)

  • Parental Investment
  • precocial
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • male
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • female
  • pre-independence
    • provisioning
      • female
    • protecting
      • male
      • female
  • post-independence association with parents

Lifespan/Longevity

Arabian tahrs have a lifespan in captivity of up to 22 years. With predation, hunting, and destruction of habitat, the lifespan in the wild is lower. There is insufficient research to determine lifespan in the wild. The main factor limiting lifespan is the amount of resources present, which is currently linked to competition with domestic animals. (Burton and Burton, 2002; Insall, 2008)

  • Range lifespan
    Status: captivity
    22 (high) years

Behavior

Arabian tahrs are diurnal and begin grazing in the early morning for most of the day until a few hours before dusk. They travel along steep mountain grades to reach good foraging areas and available water, sometimes descending to lowlands to reach "wadis," water sources. They can be solitary but are typically found in small groups of two or three, the combination usually being a female and her young, a female and male, or a female, male, and their young. However, when they are bred in captivity, they form larger groups with more complex social hierarchies. This suggests the possibility that social structures in the wild have changed as a result of their extreme rarity and isolation to potentially marginal habitat. (Insall, 2008; Robinson, 2005; Insall, 2008; Robinson, 2005)

  • Average territory size
    .3 km^2

Home Range

Arabian tahr males mark their territory by scratching their hooves on the ground and urinating. The average area covered by an Arabian tahr is 0.3 square kilometers, which usually contains water and vegetation. When this water supply is not enough, they temporarily travel outside of their territory. (Robinson, 2005; Insall, 2008; Robinson, 2005)

Communication and Perception

Visual, auditory, and chemical communications are used by Arabian tahrs. Males use urine to mark territory as well as their mates.

Food Habits

Arabian tahrs are strict browsers, eating mainly leaves, bark, seeds, and fruits in the diverse vegetation they prefer. Water is usually the limiting resource and droughts can seriously affect Arabian tahr populations. ("ARKive: Images of Life on Earth", 2009a)

  • Plant Foods
  • leaves
  • wood, bark, or stems
  • seeds, grains, and nuts
  • fruit

Predation

Their rubbery hooves allow quick and sure movements around cliffs and rocks. The horns are pointed backwards but are robust and could be used defensively. Long, shaggy, reddish-brown pelage helps to camouflage them in their scrubby habitat. They were once preyed on by Arabian leopards (Panthera pardus nimr) and humans (Homo sapiens). ("ARKive: Images of Life on Earth", 2009a)

  • Anti-predator Adaptations
  • cryptic

Ecosystem Roles

Arabian tahrs are an indicator of the condition of their habitat. They are currently only found in remote, mountainous areas with relatively higher precipitation. Their presence is important for Arabian leopards, which prey on them. Arabian leopards number fewer than 250 individuals in the wild. Arabian tahrs also impact vegetation communities through their browsing. (Insall, 2008; "ARKive: Images of Life on Earth", 2009b)

Economic Importance for Humans: Positive

Arabian tahrs were once hunted for sport and meat. Some poaching may continue, but is illegal, as Arabian tahrs are highly endangered and protected by law. Some Arabian tahrs are bred in captivity and much is learned about their life histories in that context, since observations in the wild are difficult to obtain. (Insall, 2008; "ARKive: Images of Life on Earth", 2009a)

  • Positive Impacts
  • food
  • research and education

Economic Importance for Humans: Negative

There are no known adverse effects of Hemitragus jayakari on humans. (Insall, 2008)

Conservation Status

The number of Arabian tahrs is currently estimated to be fewer than 2,500 individuals. Subpopulations are fragmentary and small, with none having more than 250 individuals. Populations continue to decline despite protective measures and captive breeding. The largest cause of decline in Arabian tahrs is loss of habitat. Poaching and competition with domestic goats for resources also contribute to the decline. Poaching still threatens tahrs, as does diseases spread by domestic animals. In the future, increased mining threatens habitat quality and water availability. (Insall, 2008; Insall, 2008)

In Oman, it is illegal to hunt Arabian tahrs. Measures taken to enforce this include appointing tribesmen to be tahr guards, thus protecting their habitat. Also, local farming families have been notified to keep their livestock away from contact with the tahrs. Currently, tahrs living in captivity are not considered ready for release and reintroductions have not been attempted. Future measures to save wild Arabian tahrs include better systems for raising them in captivity as well as establishing official reserves. Stronger enforcement of current rules is necessary as well. (Insall, 2008)

Other Comments

Debate is currently being held over whether or not the three existing species of tahrs deserve a monospecific genera. Hemitragus is currently used for all three, but it is suggested that this name should only apply to Himalayan tahrs (Hemitragus jemlahicus). The suggested generic name for Arabian tahr would be Arabitragus, and Nilgiritragus would be used for Nilgiri tahr (Hemitragus hylocrius). The alternative name for Hemitragus jakari would then be Arabitragus jakari. (Ropiquet and Hassanin, 2005)

Contributors

Alexander Emmitt (author), University of Michigan-Ann Arbor, Phil Myers (editor, instructor), Museum of Zoology, University of Michigan-Ann Arbor, Tanya Dewey (editor), Animal Diversity Web.

Glossary

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

World Map

acoustic

uses sound to communicate

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

cryptic

having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.

diurnal
  1. active during the day, 2. lasting for one day.
endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

folivore

an animal that mainly eats leaves.

food

A substance that provides both nutrients and energy to a living thing.

herbivore

An animal that eats mainly plants or parts of plants.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

monogamous

Having one mate at a time.

motile

having the capacity to move from one place to another.

mountains

This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.

native range

the area in which the animal is naturally found, the region in which it is endemic.

pheromones

chemicals released into air or water that are detected by and responded to by other animals of the same species

scent marks

communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them

scrub forest

scrub forests develop in areas that experience dry seasons.

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

sexual ornamentation

one of the sexes (usually males) has special physical structures used in courting the other sex or fighting the same sex. For example: antlers, elongated tails, special spurs.

social

associates with others of its species; forms social groups.

solitary

lives alone

tactile

uses touch to communicate

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

visual

uses sight to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

year-round breeding

breeding takes place throughout the year

young precocial

young are relatively well-developed when born

References

Wildscreen. 2009. "ARKive: Images of Life on Earth" (On-line). Arabian Leopard. Accessed May 08, 2009 at http://www.arkive.org/arabian-leopard/panthera-pardus-nimr/biology.html.

Wildscreen. 2009. "ARKive: Images of Life on Earth" (On-line). Arabian Tahr. Accessed May 08, 2009 at http://www.arkive.org/arabian-tahr/hemitragus-jayakari/info.html.

Burton, M., R. Burton. 2002. International Wildlife Encyclopedia. New York City: Marshall Cavendish.

Burton, M., R. Burton. 2002. Tahr. Pp. 2612-2613 in International Wildlife Encyclopedia, Vol. 17, 3 Edition. New York, NY: Marshall Cavendish.

Insall, D. 2008. "IUCN 2008 Red List" (On-line). Arabitragus jayakari. Accessed May 08, 2009 at http://www.iucnredlist.org/details/9918.

Robinson, M. 2005. The Arabian Tahr: A Review of its Biology and Conservation. Newsletter of the IUCN/SSC Caprinae Specialist Group, October: 2-8. Accessed May 08, 2009 at http://pages.usherbrooke.ca/mfesta/pdffiles/Oct%2005.pdf.

Ropiquet, A., A. Hassanin. 2005. Molecular evidence for the polyphyly of the genus Hemitragus (Mammalia, Bovidae). Molecular Phylogenetics and Evolution, Vol. 36, Iss. 1: 154-168. Accessed May 08, 2009 at http://www.sciencedirect.com.proxy.lib.umich.edu/science?_ob=ArticleURL&_udi=B6WNH-4FG2X4F-1&_user=99318&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000007678&_version=1&_urlVersion=0&_userid=99318&md5=a59aaed2f851711a2043f5518da8f80d.