Re-introduction of sand gazelle into the Uruq Bani Ma’arid Protected Area, Saudi Arabia

Summary

The sand gazelle (Gazella subgutturosa marica) had been absent for more than 30 years from the Uruq Bani Ma'arid Protected Area, a 12,000 square kilometre wilderness on the western edge of Saudi Arabia's Empty Quarter, when the King Khalid Wildlife Research Centre, managed by the Zoological Society of London, began re-introducing captive-bred stock in 1995. Two hundred and ten gazelles from an intensively managed captive herd of 400 to 600 were released in social groups across three sites over two years, with pregnant and non-pregnant females compared to test whether releasing females already carrying young could boost effective founder numbers, and roughly 20 percent of adults fitted with radio collars for monitoring. In the first year, 80 percent of released animals remained in the protected area, with confirmed mortality of 12.5 percent and long-range dispersal of up to 500 kilometres accounting for most of the rest. Exceptional rains in 1995 and 1996 drove strong reproduction, with up to 80 percent conception and twinning rates and some females producing two litters within a year, though breeding slowed markedly during the 1999 to 2001 drought without further intervention. By year three the core population exceeded the 300-animal target, and by 2006, eleven years on, local concentrations of 50 to 70 animals were still observed. The project rated itself Highly Successful, citing success indicators met by year three and substantially exceeded by years five to ten, aided by a soft-release protocol and favourable initial rainfall.