The Unfenced Desert Towards a strategy for eco ... - Nwrc.gov.sa

temperatures vary greatly between different areas, ranging from 18 o C in the far north-
west, to 31 o C on the south-western coasts (Fisher and Membery 1998). An absolute
maximum of 40-50 o C has been measured over much of the Peninsula, lower only at the
high western elevations (MEPA unpublished data). Rainfall is the main meteorological
event of the year, falling between May -June and October-December, but with high interannual
variation and extreme local patchiness (Mandaville 1990). Total annual rainfall
ranges between 400mm in the south-western highlands
(Fisher and Membery 1998).
The dominant feature of Arabia’s floral and faunal elements has been described as one of
alternate immigration and isolation, arising from the intermittent presence of land
bridges between Africa and Asia, and alternating periods of aridity and high rainfall
(McKinnon 1990). Wildlife has originated therefore from the Palearctic (North Africa,
northern Asia and Europe), tropical east Africa, and southern and eastern Asia
(Kürschner (1998). The fauna present in Saudi Arabia today and in the recent past is a
product of a process of influx during pluvial periods, followed by reduction in numbers
and range during arid periods, some marked by waves of extinction. Surviving forms
have become isolated by shrinking habitat, e.g. Asir juniper forest highlands, leading to
relict populations (the Mimusops tree groves of the Asir), modified subspecific forms (the
Asir magpie Pica pica asirensis), and the evolution of distinct endemic taxa (Arabian
woodpecker Dendrocopus dorae, Yemen thrush Turdus menachensis, and Philby’s rock
partridge Alectoris philbyi; and some 170 plant species in the south-western highlands)
(Child and Grianger 1990; McKinnon 1990). The Peninsula’s mammal assemblage too
reflects a mixture of Asia (grey wolf Canis lupus, red fox Vulpes vulpes, Blanford’s fox
Vulpes cana, marbled polecat Vormela peregusna), with a strong African influence
(Hamadryas baboon Papio hamadryas, sand cat Felis margarita, caracal Caracal caracal,
Rueppell’s fox Vulpes rueppelli, honey badger Mellivora capensis, genet Genetta felina), and the
presence of endemics such as the Arabian oryx Oryx leucoryx (.Child and Grainger 1990;
Harrison and Bates 1991)
Saudi Arabia is important also for species which breed outside its borders, but use the
Arabian Peninsula as a stepping stone between the western Palearctic and Africa. It’
estimated that 2,000 to 3,000 million birds migrate south across Arabia each autumn
(Rands 1989). Some of these approximately 190 migrant species are globally threatened,
and all are vulnerable to persecution, particularly during stop offs or when over-wintering
on the Peninsula (Rands 1989; NCWCD unpublished data).
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