A study on abundance, group size and composition of Soemmering's Gazelle (Gazella soemmerringii) in Awash National Park and Alledeghi Wildlife Reserve, Ethiopia

Abstract

Population status, group composition and social organization of the Soemmerring's gazelle (Gazella soemmeringii) were studied at Awash National Park (ANP) and Alledeghi Wildlife Reserve (AWR) in 2000. Total count method was used to assess the population size of the gazelle. Thirteen routes, each route being two kilometres away from the other, were designated at AWR for the vehicle survey. Similarly, 10 routes, each being one kilometre away from the other, were designated at ANP. The results revealed a mean population of 457.8 individuals in the selected study site in Alledeghi Wildlife Reserve, and 41.45 in Ilala Sala. Grouping pattern showed that cohesion was stronger. The large females group containing juveniles and of adult males were the two main social units. Mean group size in ANP was 4.4 whereas that of AWR was 16.8 individuals (p>0.001). A paired-sample t-test comparison of the total frequency of categories of the group sizes for the two areas showed a significant difference (p=0.026). Local variation in group size did exist in AWR (p=0.021). But this variable showed no significant difference (p= 0.414) in ANP. Herds of 6–10 were most common at Ilala Sala and 20–50 at AWR. However, herd size ranges from 3–250 individuals at AWR. Comparing seasonal variations in group sizes showed no significant difference. It is presumed that alteration of the original habitats might have an effect on the group pattern and social organization of study population as observed from one of the study site.

Keywords: abundance, Alledeghi Wildlife Reserve, Awash National Park, group size, Soemmerring's gazelle

SINET: Ethiopian Journal of Science Vol. 28(2) 2005: 161-170