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bioRxiv · 10.1101/2021.05.18.444309

Urbanization, Bird Species Richness And Abundance Within Ibadan Metropolis, Nigeria

Adegbola, F. O.·Adeyanju, T. A.·Iwajomo, S. B.·Ayodele, I. A.
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Abstract

Urbanisation is considered as one of the most profound threat to wildlife, with habitat loss and fragmentation being predominant. This study assessed the impacts of urbanisation on richness, abundance of bird species within Ibadan metropolis, Nigeria. A uniform grid of 500 square meters was installed on the map of Ibadan Metropolis using QGIS to produce 499 grid points distributed across the five urban local governments. 100 grids were selected randomly, identified with mapinR software application and surveyed with 5 point counts within each gird, established at 200m interval to avoid double counting. Each point count was observed for 5 minutes using a pair of 8x42mm binoculars within a 50m radius. Habitat variables like number of buildings, trees, paved roads, communication masts were also recorded. A total number of 56 species of birds were observed at the end of the assessment, classified into 30 families. The test of statistics showed that there was no statistically significant difference in bird species richness between the Local Governments. The test of statistics showed that there was no statistically significant difference in bird species abundance between the local governments. The test of between-subjects effects revealed that there were no statistical significant effects when all the habitat variables were computed in the model on species richness. The number of paved roads and number of vehicles showed a significant effect on bird species abundance while others variables in the model did not exact statistically significant effects on bird species abundance. The study therefore concluded that habitat actions due to urbanisation have not affected the richness and abundance of birds species found in all the local governments. The only habitat variables that have currently exacted significant effect on species abundance within the metropolis are number of vehicles and paved roads.

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Adegbola, F. O., Adeyanju, T. A., Iwajomo, S. B., Ayodele, I. A.. 2021-05-18. Urbanization, Bird Species Richness And Abundance Within Ibadan Metropolis, Nigeria. https://doi.org/10.1101/2021.05.18.444309

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