Conservation status of re-introduced red-necked ostrich in Mahazat as-Sayd, Saudi Arabia

Summary

The Arabian ostrich subspecies went extinct in the wild by the late 1930s through firearm-enabled hunting, and Saudi Arabia's National Wildlife Research Center chose the closely related red-necked ostrich (Struthio camelus camelus) from Sudan as its ecological substitute for re-introduction into the 2,200 square kilometre, fully fenced Mahazat as-Sayd Protected Area, one of the world's largest enclosed reserves. Founding stock arrived in 1988 to 1989, with the first seven birds released from a pre-release enclosure into the reserve in 1994; from 1994 to 2001, 96 red-necked ostriches were released in total, though over half (58.8 percent) of captive-bred adults died after release regardless of pre-release conditioning time, largely from summer heat and water scarcity within the fenced reserve, which prevents natural migration to better conditions. Wild breeding began promptly, however: the first clutch hatched in 1997 with only two of twelve chicks dying, and by 2005 to 2006 seven monitored nests produced 197 eggs and 93 hatched chicks with over 60 percent survival, suggesting wild-hatched chicks adapt better than captive-bred adults. Severe mortality events recurred, including over 50 deaths during a 2005 drought and 53 carcasses in a later year, 96 percent of them chicks. The population is estimated at 90 to 100 birds, but individuals remain unmarked, limiting precise monitoring. The project rated itself Partially Successful, noting that where no wild ostriches existed before, a significant population now exists in Saudi Arabia, despite the unresolved adult mortality problem.