| Addax | |
|---|---|
| Conservation status | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Artiodactyla |
| Family: | Bovidae |
| Subfamily: | Hippotraginae |
| Genus: | Addax Rafinesque, 1815 |
| Species: | A. nasomaculatus |
| Binomial name | |
| Addax nasomaculatus (Blainville, 1816) |
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| Distribution of the Addax | |
The Addax (Addax nasomaculatus), also known as the screwhorn antelope, is a critically endangered species of antelope that lives in the Sahara desert. As suggested by its alternative name, this pale antelope has long, twisted horns. It is closely related to the oryx, but differs from other antelopes by having large square teeth like cattle and lacking the typical facial glands. Although extremely rare in its native habitat due to unregulated hunting, it is quite common in captivity.[1] They are sometimes hunted as trophies on ranches in the United States.
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It is believed the name “Addax” is obtained from an Arabic word meaning a wild animal with crooked horns; and the word “nasomaculatus” comes from the Latin words “nasus” (or the prefix “naso”) that means nose and “macula” that means a spot or spotted and the suffix –“atus” refers to the spots and facial markings of the antelope. Bedouins uses another name for the Addax, that is the Arabic term “bakr” (or “bagr”) “al wahsh”, which literally means the cow of the wild. The name can be used to refer to other ungulates as well.
The Addax stands about 1 metre (3.3 ft) at the shoulder and its weight varies from 60 to 120 kilograms (130 to 260 lb). The coloring of their coat varies with the season. In the winter it is grayish brown with white hind quarters and legs, which is weird because scientists cannot find out why, because it doesn't get cold where they are located. In the summer, the coat turns almost completely white or sandy blonde. Their head is marked with brown or black patches that form an ‘X’ over their nose. They have a scraggly beard and prominent red nostrils. Long black hairs stick out between their curved and spiraling horns ending in a short mane on the neck. Horns, found on both males and females, have two to three twists and can reach 80 centimetres (31 in) in females and 120 centimetres (47 in) in males. Their tail is short and slender, ending in a puff of hair. The hooves are broad with flat soles and strong dewclaws to help them walk on soft sand.[2]It exhibits secondary sexual dimorphism. The Addax naturally lives upto 19 years, but the life span can be extended to 25 years under captivity.
These animals are mainly nocturnal, particularly in summers. In the day they dig into the sand in shady locations and rest in these depressions, which also protect them from sandstorms. Addax herds contain both males and females and have from two to twenty animals, though they had more in previous times. They will generally stay in one place and only wander widely in search of food. Addax have a strong social structure, probably based on age, and herds are led by the oldest male or female. Herds are more likely to be found along the northern edge of the tropical rain system during the summer and move north as winter falls. Addax are able to track rainfall and will head for these areas where vegetation is more plentiful. These herds are led by a dominant male. Small nomadic herds can also be found, searching for food. These animals are territorial, and males defend their own territory.
Due to its slow movements, the Addax is an easy target for predators like lions, human, African hunting dogs, cheetahs and leopards. Caracals, hyenas and servals attack calves. Addax are do not get annoyed easily, though individuals often turn aggressive at being disturbed.
They are amply suited to live in the deep desert under extreme conditions. Addax can survive without free water almost indefinitely, because they get moisture from their food and dew that condenses on plants. Scientists believe that the Addax has a special lining in its stomach that stores water in pouches to use in times of dehydration. They also produce highly concentrated urine to conserve water.
Addax live in desert terrain where they eat grass, and leaves of what shrubs, leguminous herbs and bushes are available. Their staple diet are the Aristida and Acacia grasses; perennials which turn green and sprout at the slightest bit of humidity or rain. The Addax eat only certain parts of the plant and tend to crop the Aristida grasses neatly to the same height. By contrast, when feeding on Parnicum grass, the drier outer leaves are left alone while they eat the tender inner shoots and seeds. These seeds are important part of the Addax's diet, being their main source of protein.[2] They rarely drink water but derive moisture from whatever foliage available.
Females are sexually mature at 2 to 3 years of age and males at about 2 years. Breeding occurs throughout the year but is peak during winter and early spring. Gestation period lasts 257-270 days (about 9 months). Females may lie or stand during the delivery, after which one calf is born. A postpartum estrus occurs after 2-3 days. The calf weighs 5 kilograms at birth and is weaned at 23-29 weeks.
The Addax inhabits arid regions, semideserts and sandy and stony deserts, but today are only found in rare pairs or as individuals in the Sahara desert and a few neighboring regions. The Addax is extinct in Jordan since 1900 and in Egypt and Morocco by the mid 20th Century. It was once abundant in north Africa, native to regions like Chad, Mauritania and Niger. By 1972, the Addax was found mainly in Rio de Oro, Mauritania; north Mali and Chad; with some in Algeria, South Libya, and North Sudan. It was rare everywhere except in the uninhabited area in Mauritania and Mali in the western Sahara. It is now found in scarce populations in Mauritania, Mali, Chad, Niger and almost extinct in Sudan, Algeria, Egypt, Libyan Arab Jamahiriya and western Sahara.
In ancient times, Addax occurred from Northern Africa through Arabia and the Levant. Pictures from Egyptian tombs show them being kept as domesticated animals in around 2500 BC. More recently, Addax were found from Algeria to Sudan, but due mainly to overhunting, they have become much more restricted and rare.[1] The Dama Gazelle and Scimitar Oryx are also found in the same region. These are easy to hunt due to their slow movements, particularly using motorized vehicles and automatic weapons. Moreover their meat and leather are highly prized. Other threats include chronic droughts in the deserts, habitat destruction due to more human settlements and agriculture. It is believed that less than 500 individuals exist in the wild today, most of the animals being found between the Termit area of Niger and the Bodélé region of Western Chad.
In Israel, the Yotvata Hai-Bar Nature Reserve breeds Addax in order to restore them to the wild. Although enormous reserves, such as the Ahaggar National Park and Tasilli in Algeria, the Ténéré in Niger, the Ouadi Rimé-Ouadi Achim in Chad, and the newly established Wadi Howar National Park. in Sudan cover areas where Addax previously occurred, some do not keep Addax anymore due to less resources. Addax have been introduced in Tunisia and Morocco, firstly in Bou Hedma National Park (Tunisia).