Sex ratios of Arabian Sand Gazelle Gazella Marica Thomas, 1897 in the Mahazat as-Sayd Protected Area, Saudi Arabia

摘要

The sex ratio of a population of Arabian Sand Gazelle in Mahazat as-Sayd Protected Area in central western Saudi Arabia was compared to that determined from 296 skulls collected from the same area. Skulls were collected between March 2008 and March 2009 during a period of mass die-off caused by a severe drought. Most abundant were male skulls ageing between 18 and 24 months. The skulls of natural mortalities indicated an imbalanced sex ratio skewed towards males (1.39:1), compared to a sex ratio slightly skewed towards adult females (1:1.07) in the living population. Horn lengths of males and females were significantly shorter in the wild population of Mahazat as-Sayd than compared to an analogous population in captivity (King Khalid Wildlife Research Centre, KKWRC, Saudi Arabia). Possible causes for diverging sex ratio were linked to increased male mortality during the drought. Male mortalities and female biased sex ratio are discussed in the light of territoriality, predation, poor environmental conditions and limited opportunities to migrate.