The decline of the scimitar oryx population began as a result of climate change during the Neolithic period, and later it was hunted extensively for its horns.

Today, it is bred in captivity in special reserves in Tunisia, Morocco, and Senegal, and on private exotic animal ranches in the Texas Hill Country, United States.

The nomenclature has undergone various changes since then, with the introduction of names such as Oryx tao, O. leucoryx, O. damma, O. dammah, O. bezoarticus, and O. ensicornis.

Over 100 years later in 1951, Sir John Ellerman and Terence Morrison-Scott found that the name Oryx algazel was also ineligible for use.

[7] The first molecular study of this species (published in 2007) observed genetic diversity among European, North American, and some other captive groups.

A study in 2004 revealed that C. parvum or similar organisms infected 155 mammal species, including the scimitar oryx.

[19] Oocysts of a new parasite, Eimeria oryxae, have been discovered in the feces of a scimitar oryx from Zoo Garden in Riyadh.

[21] The scimitar oryx was a very sociable animal and traveled in herds of two to 40 individuals, generally, led by a dominant bull.

Predators, such as lions, leopards, hyenas, cheetahs, golden jackals, vultures, and Cape hunting dogs, mostly kill weak and young oryx.

[14][15] The habitat of the scimitar oryx in the wild was steppe and desert, where they ate foliage, grass, herbs, shrubs, succulent plants, legumes, juicy roots, buds, and fruit.

They can get water from water-rich plants such as the wild melon (Citrullus colocynthis) and Indigofera oblongifolia and from the leafless twigs of Capparis decidua.

In the night or early morning, they often search for plants such as Indigofera colutea, which produce a hygroscopic secretion that fulfills water requirements.

[6] The scimitar oryx once inhabited grassy steppes, semideserts[15] and deserts in a narrow strip of central north Africa (especially in Niger and Chad).

[6] It was widespread on the fringes of the Sahara, mainly in subdesert steppe, the grassy zone between the real desert and the Sahel, an area characterized by an annual rainfall of 75–150 mm (3.0–5.9 in).

[23] Following the Neolithic Subpluvial, around 7500 to 3500 BC, the "green Sahara" became dry and the scimitar oryx's population began to decline due to a loss of suitable habitat.

[24] The decline of the southern population accelerated as Europeans began to settle the area and hunt them for meat, hides, and horn trophies.

[6][25] Roadkill, nomadic settlements near watering holes (the oryx's dry-season feeding places), and introduction of cattle and firearms for easy hunting have also reduced numbers.

[24][26] The IUCN lists the scimitar oryx as extirpated in Algeria, Burkina Faso, Chad, Egypt, Libya, Mali, Mauritania, Morocco, Niger, Nigeria, Senegal, Sudan, Tunisia, and Western Sahara, and has assessed it as extinct in the wild since 2000.

[1] Chad is currently leading a project to reintroduce the species in Ouadi Rimé-Ouadi Achim Game Reserve, with the support of the Sahara Conservation Fund and the Environment Agency of Abu Dhabi.

[31] A captive bred group was released into an acclimation enclosure within the Ouadi Rimé-Ouadi Achim Faunal Reserve in 2016, then reintroduced into the wild.

In 2017, another herd of 75 scimitar-horned oryxes arrived in an operation led by Chad's Ministry of Environment and Fisheries and the Sahara Conservation Fund.

In ancient Egypt, scimitar oryxes were domesticated or tamed, possibly to be used as offerings for religious ceremonies or as food.

Its hide is considered high-quality, and the king of Rio de Oro sent 1,000 shields made of it to a contemporary in the Middle Ages.

[33] In 2015, Yellow Nose, a scimitar oryx that lives in Portland, Oregon, escaped and startled hikers in Forest Park.