Community structure and abundance of avian and non-avian vertebrate fauna of Dumbi Inselberg and adjacent woodland in Zaria, northern Nigeria

Abstract

The ecology of inselbergs is poorly understood, and very scanty information on Nigerian inselbergs exists. A 24-month (October, 2009 to September, 2011) synecological survey of the vertebrate fauna of the Dumbi Inselberg (007^o39.3’E; 0^o 57.7’N) in Zaria, northern Nigeria, was carried out as a case study for inselbergs in the Northern Guinea Savanna ecoloical zone. It aimed at documenting baseline information on the vertebrate fauna of the inselberg. Bird abundance and diversity were determined by the Point Count Technique. The presence of other vertebrate taxa was established through vocal calls, faecal droppings, trails, animal remains and visual observations. Estrildidae was the dominant family of the avian community. There was no significant difference in bird abundance between the two years (p>0.05). However, bird abundance between sites and between months differed significantly (p<0.05). An abundance of testudines was noted during the wet period of the study. Eight species of mammals were recorded during the survey. Other vertebrate taxa encountered included, reptiles (9 species) and amphibians (5 species). Most of the disturbances in the inselberg and its environs were mainly due to human activities. Managing the inselberg and their environs to increase the abundance of birds and other fauna may be achieved through restorative management of degraded habitats, which should include reforestation with native flora. This will facilitate increase in vertebrate diversity and abundance. As a means of preserving its unique ecology, a community-based conservation intervention programme is recommended for the Dumbi Inselberg.

Keywords: bio-diversity, ecology, inselberg, reforestation, management, vertebrate fauna.