Bird Diversity in Nensebo Moist Afromontane Forest Fragment, South Eastern Ethiopia.

摘要

Background: Birds are one component of biodiversity. Ethiopia is rich in biodiversity resources. The avian diversity record is far from complete. There is no scientifically documented information on bird species composition and abundance at Nensebo forest. The objective of the study was to assess species composition, relative abundance and distribution of birds at Nensebo forest in southern Ethiopia. Methods: We employed a stratified random sampling technique with our study area stratified into two dominant habitat types: moist Afromontane forest and modified habitat. Within strata, we established 20 transect lines of 1km length and 0.25km width to sample 27.75% of the study area. We used line transect count methods aided by binoculars to estimate avian species diversity and distribution. We employed quantitative biodiversity indices, such as Shannon wiener diversity indexes to compare species diversity among habitat types and two way ANOVA to analyze the effect of season and habitat on bird species richness and abundance. Results: A total of 105 bird species consisting of 1 endemic, 8 near endemic, 1 globally threatened and 9 Palearctic migrants were recorded in Nensebo forest. Species richness and abundance varied between habitat types in Nensebo forest with mean species richness greater in modified habitat (mean= 4.70 ±1.65) as compared to moist Afromontane forest habitat (mean= 3.95 ±4.12, F=94.66 P<0.001). Additionally, modified habitat (Shannon diversity index= 4.131) harbored higher diversity of birds as opposed to Afromontane forest habitat (Shannon diversity index=3.79). Conclusion: The Nensebo forest has high avian species diversity including several endemic and endangered species revealing the importance of this site for bird conservation. Although we found that habitat heterogeneity favored bird species diversity, moist Afromontane habitat is critical for forest obligate species. Hence, sustainable bird conservation strategies including land use planning should be initiated for this area.