Gazella dama

Gazella dama mhorr, Photo: Michael Lahanas

Cladus: Eukaryota
Supergroup: Opisthokonta
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Cladus: Deuterostomia
Phylum: Chordata
Subphylum: Vertebrata
Infraphylum: Gnathostomata
Superclassis: Tetrapoda
Classis: Mammalia
Subclassis: Theria
Infraclassis: Placentalia
Superordo: Cetartiodactyla
Ordo: Artiodactyla
Subordo: Ruminantia
Familia: Bovidae
Subfamilia: Antilopinae
Genus: Gazella
Species: Gazella dama

Name

Gazella dama (Pallas, 1766)

Synonyms

* Nanger dama

References

* IUCN link: Gazella dama (Pallas, 1766) (Critically Endangered)

Vernacular names
Internationalization
العربية: غزال المهر
Deutsch: Damagazelle
English: Dama Gazelle
Español: Gacela de Mohor
Suomi: Punakaulagaselli
Svenska: Damagasell

The Dama Gazelle (Nanger dama; formerly Gazella dama) is a species of gazelle. It lives in Africa in the Sahara desert and migrates south in search of food during the dry season. Their habitat includes open steppes, bushy, grassy steppes, semi-desert, and deserts, while their diet includes grasses, leaves, shoots, fruit, and especially Acacia leaves. After the rains return and the desert plants turn green, the gazelles move north back to the Sahara. Poaching and destruction of their habitat have greatly diminished their numbers, and they no longer live in large herds.


Natural history

These animals are white with a tannish-brown head and neck. Both sexes usually have medium length ringed horns curved like an "S." Males' horns are about 14 inches long, while females' horns are much shorter. The gazelles' heads are small with narrow muzzles, their eyes are relatively large, and they have longer necks and legs than most gazelles. These animals are between 90 to 110 cm (35 to 43 in) tall at the shoulder, weigh between 35 and 75 kg (77–167 lbs) and have a life span of up to 12 years or 18 in captivity.[2] An interesting fact is that after just a few days following birth, dama young are strong enough to follow the herd, and after a week, they are able to run as fast as the adults. They can reach running speeds of to up 100 to 110 km/h (62 to 68 mph).[citation needed]

Dama gazelles have been split into 7, 5, or 3 subspecies, with 3 the currently most cited number. These subspecies are the Addra gazelle, Dama gazelle and Mhorr gazelle. The dama gazelle is believed to be extinct in the wild, with both other forms critically threatened.

Damas are considered the largest type of gazelle, with incredibly long legs, which provide extra surface area on their body to dissipate heat, one of the many ways they stay cool in their hot desert environment. They also tend to need more water than some of their desert relatives, but they can withstand fairly long periods of drought. Unlike many other desert mammals, dama are a diurnal species, which means they are active during the day.

Always on the alert, dama use a behavior called "pronking" to warn herd members of danger. "Pronking" involves the animal hopping up and down with all four of their legs stiff, so that their limbs all leave and touch the ground at the same time. Males also establish territories, and during breeding season they actively exclude other mature males. They mark their territories with urine and dung piles and secretions from glands near their eyes.

Subspecies status and conservation

The Mhorr Gazelle subspecies, Nanger dama mhorr, is extinct in the wild but present in breeding programs in Europe and America,[3][3] and several reintroduction efforts have introduced animals into former and similar habitat areas.

The Dama subspecies, Nanger dama dama, is extinct in the wild and not represented in captivity.

The Addra subspecies, Nanger dama ruficollis, is still present in the wild but quickly declining. Its numbers have fallen by 80% over the last decade, and the Dama Gazelle is now listed as Critically Endangered, though there are still as many as 2000 left. They occur in poor countries and little action is taken to protect the species, the national parks are not well guarded and poachings still occur. Captive populations are managed in zoos in Africa and America.

Threats to survival

Three types of threats harm the Dama Gazelle. These threats are biological threats, geological threats and human threats. One biological threat that the Dama Gazelle faces is seasonal rainfall. They don’t need a lot of rainfall but they need more than other desert animals. They are not as resistant and perish from a lack of water during the drought season [4] .[4] The environment has become ill suited for them. Disease also kills off a lot of the Dama Gazelle population. There are many people and domesticated animals that come onto their land. If they pick up a disease from one of these domesticated species they may not be able to fight it off and die.[4] Also, a big reason for the decline of this gazelle is habitat destruction. Men go out and cut down the branches of the trees that these gazelles need to feed from. As a result, a lot of the trees die and the gazelle cannot eat [5] [5] . Human threats are the most dangerous of threats to the Dama Gazelle. The main reason this species of gazelle is endangered is because of mechanized hunting. The hunters use vehicles and firearms now which also increase the decline of the Dama Gazelles [5] . A lot of farmers take their livestock out in fields to forage. By doing this, they eliminate a lot of the food that the gazelles eat [5] . There is a lot of war going on in Africa. A lot of this civil unrest affects the life of the Dama Gazelle.[5] Some of the gazelles inhabit the country of Sudan. For many years there has been a lot of war going on there which would be hard on any species of mammal. Since the gazelle is already having a hard time surviving these conditions have made its habitat unsuitable for optimal survival [6] . Also, a new threat that the gazelle faces is tourism. A lot of people want to take pictures of this endangered species and in doing so they accidentally kill them, especially during the hot season.[5] Gazelles will run away from perceived danger, and in the hot season may overheat and die of stress.

Conservation efforts

As of today, there have been very few actions taken in the conservation of the Dama Gazelle.[4] The few measures that have been taken are reserves so the animal can live in peaceful environment and captive breeding to help rebuild the populations.

There was a reserve for Mhorr gazelles set up in 1971 to help avoid extinction of the Dama Gazelle. This reserve is in Spain and is called The Parque de Rescate de la Fauna Sahariana of the Estación Experimental de Zonas Áridas. This is a good way to have the animals away from the threats that are imposed on them in the wild. This reserve has been a success and is still around today.[7]

There was another reserve for the Mhorr subspecies in Chad called the Ouadi Rime-Ouadi Achime Faunal Reserve [5] . This reserve was effective from 1978–1987, but due to civil war, the reserve was abandoned.[4] Captive breeding is a very popular way to help an endangered species repopulate. This is a good way to have the species reproduce in captivity and then free them back into the wild. It can be a helpful way for the species to recover. It may be bad because small population sizes are used and there may not be enough genetic variance or there may be interbreeding between the animals. This is the most effective way to avoid the species from going extinct.[7]
Addra Gazelles, part of the breeding program at the National Zoo

Most Addra gazelles are now managed in zoos and AZA institutions in the United States according to a Species Survival Plan.[4] Small population size and inbreeding are a serious concern in this population due to the increased parasite load and reduced reproductive viability [8] [8] No reserves for this subspecies exists in the wild, and few substantial in situ conservation efforts have been mounted due to the political situation in the current fragmented addra habitat.

To guarantee the survival of this species, there needs to be more reserves created to ensure the survival of this animal. They need to be created in the Sahelian and Saharan zones because this is where the highest concentration of gazelles reside [5] . To help this species survive, humans must help them maintain a healthy captive population and help preserve their habitats in the wild.[4]

References

^ Newby et al. (2005). Gazella dama. 2006. IUCN Red List of Threatened Species. IUCN 2006. www.iucnredlist.org. Retrieved on 11 May 2006. Database entry includes justification for why this species is critically endangered
^ Gazella Dama Historical Studbook, AZA, 2008
^ a b Francois Lamarque, Amewey Ag Sid'Ahmed, Stephane Bouju,Gaoussou Coulibaly, Li, Daouda Maiga. (2007). "Confirmation of the survival of the Critically Endangered dama gazelle Gazella dama in south Tamesna, Mali". Oryx 41: 109–112. doi:10.1017/S0030605307001561.
^ a b c d e f g Antelope Taxonomic Advisory Group Addra Gazelle. 2008.
^ a b c d e f g h J.F. Grettenberger, J.E. Newby. (1986). "The Status and Ecology of the Dama Gazelle in the Air and Tenere National Nature Reserve, Niger". Biological Conservation 38: 207–216. doi:10.1016/0006-3207(86)90121-7.
^ Thompson A: Sudan’s migrating wildlife wows scientists.. MSNBC, 2007.
^ a b F. Berlinguer , R. Gonza´lez, S. Succu, A. del Olmo, J.J. Garde, G. Espeso, M. Gomendio, S. Ledda, and E.R.S. Roldan. (2008). "In vitro ooctye maturation, fertilization and culture after ovum pick-up in an endangered gazelle (Gazella dama mhorr)". Theriogenology 69 (3): 349–359. doi:10.1016/j.theriogenology.2007.10.001. PMID 18022681.
^ a b Jorge Cassinello, Montserrat Gomendio, Eduardo R.S. Roldan. (2001). "Relationship between coefficient of inbreeding and parasite burden in endangered gazelles". Conservation Biology 15: 1171–1174. doi:10.1046/j.1523-1739.2001.0150041171.x.

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