The study of the carnivore guild is the key to understanding the quantitative relationship between members of the carnivore community and establishing the influence of inter-specific competitions on species diversity. The study aimed to investigate species composition, abundance and population structure of the family herpastidae in the Nech Sar National Park (NSNP), Ethiopia. Ecological data collection on mongoose species has been carried out from September 2022 to August 2023 in bush land, grassland and forest habitats bimonthly in the park. Based on the habitat types and topography of NSNP, 10 transects, each 4-5 km long, were sampled to traverse the major habitat types in the park. Line transect distance sampling methodology was used to determine abundance and population status. DISTANCE (Version 6.0, Release 2) Software was used to asses density and abundance of mongoose populations. Three species of mongoose, namely- Egyptian mongoose (Herpestes ichneumon) slender mongoose (Herpestes sanguineus) and white-tailed mongoose (Ichneumia albicauda), were identified in the study. The overall density of mongoose in the study area was 2.31+0.16 individuals/km2 with population estimate of 943+85.59 individuals. Density and abundance estimates showed variation based on season and habitat type (P<0.05). However, there was no significant difference in species composition between seasons and habitat types. The highest species diversity (H=1.197) was recorded in bush land habitats. The population was female biased, with a 1:1.17 and 1:1.59, male to female ratio during wet and dry seasons, respectively. Adult to young (sub-adult and juvenile) ratio was 1.05:1 and 0.94: 1 during wet and dry seasons, respectively. Further research on other ecological parameters, viz. behavior, feeding habits, activity patterns, and others, is important to acquire a complete picture of mongoose ecology in the park.

Keywords: Density, carnivore guild, species composition, ecological parameters