Sex Structure and Group Size of Oribi (Ourebia ourebi) in Maze National Park, Ethiopia

Abstract

Studies on sex structure and group size of oribi (Ourebia ourebi) were carried out in the newly established Maze National Park, Southern Nations Nationalities and People’s Regional State, Ethiopia, during the wet and dry seasons from October 2009 to February 2012. A total count method was employed to determine the sex and age structure based on silent detection in an area of 220 km². The area was divided into eight counting blocks based on natural and artificial boundaries. The ratio of adult males to adult females ranged from 1:1.30 to 1:1.48 and 1:1.25 to 1:1.33 during wet and dry seasons of the study years, respectively. There were more adult females than adult males and young. Group size varied from lone individual to the upper limit of 13 and 19 during the wet and dry seasons, respectively. The largest group was found in the short grasslands and the smallest within woodland and long grasses. Many of the individuals were observed in pairs with a large number of adult male and female couples. Proper and urgent measures should be taken to limit illegal activities to conserve the wildlife of the area.

Keywords: Group size, Maze National Park, Oribi, Sex structure