Remote sensing of land use changes posing future threats to the avifauna in the Guinea Savanna zone, Nigeria

The Guinea Savanna ecosystem in Nigeria is facing unprecedented threats from land use changes, which can have far-reaching consequences for the distribution of birds. This study employed remote sensing techniques to analyze land use changes retrospectively and predicted their future impacts on avifauna distribution in the Guinea Savanna region of Nigeria. Landsat imagery from 1982 to 2022 was used to assess land use changes, while the percentage average rate of change equation was employed to predict future changes. Point count method was used to record bird species in four stratified habitats: forest, woodland, grassland and riverside, which were identified as sites being mostly affected by anthropogenic activities. Sampling was done on four points within the four habitats of four selected sites of the region, making a total of 64 sampling points, for a period of two years (2023 and 2024). Canonical Correspondence Analyses (CCA) was used to relate land use types with avifauna distribution. Our results indicated significant changes in land use, with a 50% increase in agricultural land and a 60% decrease in forest, among others like built-up areas and woodland deforestation. The result of the CCA showed the 20 most abundant bird species with clear-cut preference to a particular land use type, which predicted that future land use changes will lead to significant declines in the distribution of several bird species. We identified areas of high conservation value and recommended proactive measures to mitigate the impacts of future land use changes on avifauna distribution in the region.