The study assessed major environmental determinants influencing bird community in six wetlands over a 2-year period. A combination of visual and bird sounding techniques was used to determine the seasonal variations in bird abundance, while ordination techniques were performed to determine the influence of environmental factors on bird assemblage. A total of 1,169 birds from 25 species and 885 individuals from 23 species were identified in the wet and dry season, respectively. The shallow close marshes supported the greatest number of birds () compared to the riparian wetlands. Bird diversity was significantly higher in the wet season than in the dry season (). Cattle egret (Bubulcus ibis) and marsh warbler (Acrocephalus palustris) were the most abundant. Using the IUCN “Red List” database guide, we noted that 96.2% of birds identified were least concern (LC). The yellow weaver bird (Ploceous megarhrynchus) was the only vulnerable species (VU) and represented 3.8%. From the three variables tested, bushfire and farming practices were the major threats and cumulatively explained 15.93% (wet season) and 14.06% (dry season) variations in bird diversity and abundance. These findings will help wetland managers design conservation measures to check current threats on birds from becoming vulnerable in the future. 1. Introduction Birds play a vital role in enriching the biodiversity of wetlands. This explains why wetlands are foremost recognized as a haven for waterfowl by Ramsar International in 1971 [1]. Their sensitivity to habitat perturbation makes them suitable as bioindicators to wetland health, through their population size and composition. Globally, over 150 bird species are reportedly lost since the year 1500 AD [2]. Recent reports have shown that birds have gone extinct at an exceptionally high rate, estimated to be 1,000 to 10,000 times the natural background rate [2]. Today, one in eight bird species is threatened with global extinction, with 190 species critically endangered and particularly alarming are sharp declines in a number of formerly common and widespread species, such as cranes and some waders. The International Union for the Conservation of Nature (IUCN) “Red List” have shown documented evidence that rate of extinction is getting worse among species confined to small islands to continental scale [2]. This loss is largely due to their increasingly intolerance to the slightest ecosystem disturbance [3] which is linked to pollution [4], habitat type and bird distribution [5, 6], wetland patch size [7], cutting of mangrove vegetation [8],
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