Effects of traffic volume on wild birds and diversity indices in Awba Lake Environment, University Of Ibadan, Ibadan, Nigeria

Abstract

Daily disturbance attributed to traffic volume is believed to be an important factor determining bird population and activity in habitats with close proximity to roads. Nevertheless, not all bird species respond negatively to traffic volume. The effects of traffic volume on the distribution of birds in the Awba Lake Environment was investigated using line transects method between April and June 2014. The study area was stratified based on land use types into four sites, namely; construction site, dense, sparse habitat and road sites. A total of 10 transects measuring 300-500m were purposively laid across the four sites. All counts were made in early mornings (0700-1000 hours) and evenings (0400-0600 hours). All birds seen or heard were identified and recorded to their species. The data collected were analyzed using Analysis of Variance and Shannon-Winner diversity Index. A total of 306 individuals were recorded, divided in to 43 species belonging to 28 families. The Shannon diversity index revealed a moderate (H' 2.7806) species diversity and the mean bird species diversity did not vary with sites. The findings also revealed a higher detection of Cattle Egret and Longtailed cormorant more than any other species in the area. Time of the day significantly affected bird species diversity and richness across the sites. For further research; it might be useful to classify all the birds in Awba Lake Environment according to the frequency range of their vocalizations so that comparisons between species can be made with regard to their response to traffic volume.