Biology & ecology

Arabian oryx

The Arabian oryx is one of the rare ruminants permanently living in deserts. Surviving without drinking water in the Arabian desert, and particularly in the Rub' al-Khali or 'Empty Quarter', one of the driest regions in the world, requires performant eco-physiological adaptations. Thus its pure white coat is thought to reflect direct solar radiations. Oryx have evolved a number of adaptations concerning the range use, the plasticity of their diet, their reproduction, physiology and behaviour.

This part aims to present the most conspicuous adaptive traits of the Arabian oryx to desert environments; Range use, diet, behaviour, reproductive biology and physiology.

Range use

The range use of the Arabian oryx has been studied in reintroduction sites. It is a nomadic species that can cover long distances in the desert to reach areas with good forage and increases its range throughout life span [Tear et al., 1997]. Ranges in excess of 2,000 km² have been recorded in Oman [Stanley Price, 1989].

In 'Uruq Bani Ma'arid protected area in Saudi Arabia, mean diurnal range size exceeded 1,700 km² in spring two years after the first release [Strauss, 2002]. This range size decreased to less than 300 km² in summer, while oryx were most of the day inactive under shade [Seddon & Ismail, 2002]. In 'Uruq Bani Ma'arid, oryx gather during summer in a small part of the protected area where shade is available. Outside the hot season, Arabian oryx make less use of shade and become more opportunistic [Seddon and Ismail, 2002]; they may cover large distances to reach areas of good forage [Corp et al., 1998].