The Biology, Husbandry and Conservation Scimitar-horned Oryx ...

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Conservation
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Part 1: Biology & Conservation
SIMON WAKEFIELD, JUERGEN ENGEL & TANIA GILBERT
Former & Current Distribution of Scimitar-horned Oryx in North Africa
Red Data Book listing: Extinct in the Wild (IUCN, 2002).
In former times scimitar-horned oryx were common in large areas of northern Africa (figure 1). The
species’ range extended from the Atlantic Ocean almost up to the Red Sea and from the
Mediterranean Sea to the 15 th degree of northern latitude (Haltenorth, 1963; Schomber, 1963;
Wilson, 1980). Only the eastern boundary of their former distribution is a subject of controversy.
Some authors (e.g. Bonnet, 1909; Brehm, 1920; Flower, 1932; Harper, 1945; Dolan, 1966; Kock,
1970; Newby, 1988) state that the river Nile represented the limit of the species range, however
others (Haltenorth, 1963; Schomber, 1963; Gillet, 1965, 1966a; Mungall & Sheffield, 1994), believe
that the oryx occupied additional areas east of the river.
Being a sub- or semi-desert species, the actual distribution would have been dictated by available
habitat, and therefore the described range was never uniformly occupied (Newby, 1978, 1988).
Typically, the perennial grassland formations, dry acacia woodlands and flushes of annual herbs
and grasses, which the oryx utilise, occur where annual precipitation is between 75 and 400mm.
During the arid conditions of the last three thousand years, this has meant that the potential
distribution has been largely the northern and southern sub-desert fringes of the Sahara, and
potentially in areas such as the fringes of central Saharan mountains where local run-off supports
these vegetation communities (Devillers & Devillers-Terschuren, 2003).
The range of the scimitar-horned oryx is thought to have declined since Roman times, due to
habitat loss and hunting (Newby, 1988; Gordon, 1991). All the populations on the northern fringe
of the Sahara had certainly disappeared by the beginning of the 20th century. The southern
Sahelian range remained almost continuous until the 1960’s, became fragmented into several
larger portions during the 1970’s, persisted as two fragments in Niger and Chad during the 1980’s,
until finally the species was only thought to occur in Chad (Newby, 1988).
In 1976, scimitar-horned oryx were classified as vulnerable by IUCN. By then resident
populations had already disappeared from Algeria, Burkino Faso, Egypt, Libya, Mauritania,
Morocco, Senegal, Tunisia, and Western Sahara, leaving only four countries (Chad, Mali, Niger
and Sudan) with extant populations. Soon afterwards the oryx in Sudan, which had already been
reduced to a few isolated herds in the Darfur region, become extinct (Newby, 1982). The formerly
widespread population of Mali is believed to have become extinct in 1981 (Lamarche – in Newby,
1988), and by this time the population of Niger was reduced to probably less than 200. The last
oryx seen in Niger was a herd of four animals located between the Aϊr mountains and Termit in
1983, and scimitar-horned oryx are believed to have become extinct in Niger that year (Newby,
1988).