Bird species composition and diversity in habitats with different disturbance histories at Kilombero Wetland, Tanzania

Abstract

Wetland natural grasslands are important habi- tats for avian populations throughout the world. Unfortunately the increase of human population and rise in demand for settlements and agricul- tural land have degraded these habitats in many tropical wetlands. To effectively restore these natural grasslands and conserve avifaunal bio- diversity, understanding of the relationships be- tween habitat conditions and bird community structure are central. We used a combination of information from nearby villagers and field sur- veys to establish two important grassland habi- tats with low and high disturbance histories, and related the habitats to bird community structure. We surveyed a total of 119 sites in the two habi- tats to examine variation in the abundance, rich- ness, diversity and composition of birds at Kilo- mbero Wetland Tanzania. In total, 3049 indivi- duals, 126 species, 88 genera and 45 families were recorded from Kilombero grasslands. Our results show that grasslands with low human disturbance had more number of bird species, genera, families and diversity (both Shannon- Wiener and Simpson) than the most disturbed grasslands at p < 0.05. However, the abundance and Shannon evenness of birds were not dif- ferent (p > 0.05) between low and highly dis- turbed grassland habitats suggesting that other factors including variety of foraging sites are important. This study confirms that the wetland grasslands of Kilombero are important for con- servation of birds including rare and endemic species. It is recommended that anthropogenic disturbances should be minimized including control of fire, regulation of agricultural activities and population of cattle within the wetland sys- tem to restore and conserve biodiversity.