EFFECT OF INVASIVE PLANT SPECIES ON AVIAN SPECIES DIVERSITY AND ABUNDANCE IN SOME URBAN INSTITUTIONAL GREEN SPACES

Abstract

Invasive plant species are often considered important threats to biodiversity and ecosystems. Birds are bio-indicators of environmental health and perform other ecosystem services such as pollination, seed dispersal among  others. This study aimed to investigate the effects of invasive plant species on avian abundance and species diversity. Two sites were selected for the study: University of Jos Bauchi Road campus and Federal College of Forestry, Jos, Plateau State. We established thirteen (13) random plots of 20m x 20m each at each of the sites. Vegetation study was carried out and percentage invasive plants per plot were estimated. Each plot was visited twice and twice a day; morning and evening for bird census. A general linear model with quadratic function was used to test the relationship between the percentage of invasive plant species per plot and bird species diversity and abundance. The relationship between bird species diversity and percentage invasive plants per plot was not statistically significant. Plots with higher percentage of invasive plants recorded lower avian species diversity. There was a positive relationship between percentage of invasive plants and bird abundance, this relationship was statistically significant. T-test was used to analyze for differences in bird species diversity with time of the day. 
A Mann-Whitney U test (Wilcoxon rank sum test) was used to compare the difference in bird abundance with time of day. There was significant effect of time of day on both bird species diversity and abundance. Higher 
avian abundance and species diversity were recorded in the morning hours than evenings. Managing invasive plants will benefit conservation of ecosystems and proper and wide education is needed for tree planting schemes to always consider indigenous species.