Invasive grass (<i>Typha domingensis</i>): A potential menace on the assemblage and abundance of migratory/water related birds in Hadejia-Nguru wetlands, Yobe State, Nigeria

Abstract

The effect of invasive grass (<i>Typha domingensis</i>) on the migratory/water related birds in Hadejia-Nguru Wetlands was studied for a period of five days. Four well marked out sites were selected for the study. Identification of birds’ species was done visually and aurally using a binocular and recognition of unique songs and calls. A total of fifty (50) species of migratory/water related birds was recorded during the study. Ox bow Lake housed more of the birds species counted. Out of the 50 birds species recorded, 27 were residents, 16 migratory and 7 Afro-migrants. Garganey (<i>Anas querquedulla</i>) a migrant bird were the most abundant bird species. Canonical Correspondence Analysis showed that a weak relationship existed between the birds’ species assemblage/abundance and some environmental variables. The two most preponderant species of birds recorded were restricted to Ox bow Lake (a non-invasive grass infested area). Similarity test performed showed that the two areas not infested with invasive grass were similar in bird species abundance unlike the invasive grass infested areas. Principal Component Analysis showed variation in assemblage of bird species in the study area. The study revealed that invasive grass (<i>Typha domingensis</i>) had a debilitating effect on the migratory/water related birds in the sites investigated.

Key words: Migratory Birds, Invasive Grass, Typha domingensis, Hadejia-Nguru Wetlands, Nigeria.