The Nubian ibex (Capra nubiana) is a desert-dwelling goat species (Genus Capra) found in mountainous areas of northern and northeast Africa, and the Middle East. It was historically considered to be a subspecies of the Alpine ibex (C. ibex), but is now considered a distinct species. The wild population is estimated at 4,500 mature individuals, and it is classified as vulnerable.
Description
Nubian ibex are the smallest ibex species on Earth, following Bergmann's rule. They stand around tall at the shoulder. They are sexually dimorphic: males are significantly larger than females, with males averaging and females .
They are a light tan color, with a white underbelly; males also have a dark brown mane down their backs. Their legs have a black and white pattern. They have a lighter rump with a dark brown tail. Males begin growing a beard at age 2 or 3, which continues to grow longer and darker as they age. During the autumn breeding season, mature males grow a "rutting fur" on their breast and sides which is very dark brown. It appears in October in 3–4-year-old males, but it may appear as early as July or August in older males age 6 and up. However, not all males develop rutting fur, even at a mature age.
Nubian ibexes have long, thin horns that extend up and then backwards and down. In males, these reach around in length, while in females they are much smaller, reaching around . Male horns are thicker than female horns, and grow large bulges which prevent the horns from sliding while the males are locked in combat. Male horn growth plateaus around age 7–8, where as female horn growth plateaus around age 4–6. There is a significant relationship between the individual's age and the number of horn ridges.
Distribution
Historically, Nubian ibex were distributed across the Middle East and Northeastern Africa.
Its range today is within Egypt, Jordan, Oman, Israel, Palestine, Saudi Arabia, and Sudan. It was extirpated in Lebanon, though a captive breeding and reintroduction process is underway. It has also been extirpated in Syria. Its presence and population is uncertain in Ethiopia, Eritrea, and Yemen.
Ecology and behavior
Feeding and ecological relationships
Nubian ibex live in rough, dry, mountainous terrain, where they eat mainly grasses and leaves, especially from Acacia trees (Genus Vachellia). They forage for food on the ground and may also rear up on their hind legs to reach leaves in trees. They can climb into trees while feeding. They reduce feeding on plants with strong defenses, such as tannins and thorns. Preferred plants vary depending on the amount of rain; rainy winters result in higher feeding preference for annual plants over perennials. Ibex preferentially feed in spaces that are close to cliffs where they can easily escape predators, demonstrating a Landscape of Fear: the farther from cliffs, the more vigilant ibex become. Ibex will also spend more time feeding in green patches with high nutritional quality and that are closer to water sources.
They are preyed upon by Arabian leopards (Panthera pardus nimr), Arabian wolves (Canis lupus arabs), golden jackals (Canis aureus), red foxes (Vulpes vulpes), golden eagles (Aquila chrysaetos), and bearded vultures (Gypaetus barbatus). When alarmed, they emit a shrill call to alert other ibex of danger. They share their habitat with numerous other herbivores, including rock hyrax (Procavia capensis), Arabian oryx (Oryx leucoryx), gazelles (Genus gazella), and Asiatic wild ass (Equus hemionus). Nubian ibex have a mutualistic relationship with Tristram's starling (Onycognathus tristrumil), a small bird that eats the parasites on the ibex's skin.
They may host parasites including: the ibex fly (Lipoptena chalcomelanea), blood sucking lice (Linognathus africanus and Damalinia sp.), ticks (Hyalomma rhipicephaloides, Boophilus annulatus, and others), mites (Psoroptes cuniculi and Sarcoptes scabiei), biting flies (Oestrus sp.) and fleas. They have also been found with brain cysts caused by the parasite Taenia multiceps.
Nubian ibex have been detected with a strain of the malignant catarrhal fever (MCF) virus group of ruminant rhadinoviruses, closely related to caprine herpesvirus 2 (CpHV-2) found in domestic goats.