Over 20 years of re-introducing the Arabian oryx in fenced and free-range protected areas of Saudi Arabia

Summary

The Arabian oryx, declared extinct in the wild in Oman by 1972, has been reintroduced in Saudi Arabia since 1989 by the Saudi Wildlife Commission, combining captive breeding at the National Wildlife Research Center with two very different release strategies: the fully fenced 2,244 km2 Mahazat as-Sayd Protected Area, and the unfenced, free-ranging 12,600 km2 Uruq Bani Ma'arid on the Empty Quarter's edge. Between 1990 and 2009, 82 oryx were released into Mahazat and 174 (79 males, 95 females) into UBM, sourced from both NWRC captive breeding and each other. Mahazat's fenced population grew steadily from 9 in 1988 to a peak of 613 by 2006, but then crashed to 324 by 2008 amid severe drought years with rainfall as low as 0.01mm, since the boundary fence prevents oryx from migrating to find food during shortages and animal deaths cluster along the fence line; annual mortality reached as high as 159 animals in 2008, prompting a 2008 management plan recommending removal of surplus oryx and supplemental feeding to prevent further mass die-offs. UBM's free-ranging population, surveyed at roughly 200 animals by December 2008, has not experienced comparable crashes. Population modeling found that active management, particularly capping numbers below 70% of carrying capacity, sharply reduced extinction risk compared to no intervention. Major difficulties included the absence of protected habitat during the program's earliest years and no recent genetic diversity assessment. The project rates Mahazat Partially Successful given its recurring drought-driven mass mortality, and Uruq Bani Ma'arid Successful as a stable free-ranging population.