Habitat fragmentation and the population status of rodents in Abayum forest, Ikom, Cross River State, Nigeria

Augustine Ugar Ogogo, Francis Ebuta Bisong, Abang Neji Tawo

Department of Forestry and Wildlife Resources Management, University of Calabar, Calabar, Nigeria.
Department of Geography and Regional Planning, University of Calabar, Calabar, Nigeria.

DOI: 10.4236/ns.2013.58110                

Abstract

The threat to wildlife population is attributed to various anthropogenic activities. The main objective of this study was to identify the influence of fragment size on the population density of rodents in the study area. Fourteen (14) out of forty (40) fragments existing in the area were randomly sampled. The parameters used for the study were number, size of fragments and the corresponding population distribution of rodents in the study area. Fifty hunters in the area were also interviewed. The fragments were stratified into first, second and third order fragments on the basis of their sizes and randomly selected for the study. Indirect method of wildlife census was carried out through the observation of droppings, trail or tract, burrows, eating habits and noise. Fragment growth rate was 18 to 40 (87.5%) in 7 years. Anthropogenic perturbations in the form of cultivation of permanent cropland, settlement expansion, bush burning, timber exploitation and new settlements in areas previously thinly settled or not accessible to outsiders have resulted in disjointed ecosystems. The population density of rodents correlated with fragment size was highly significant ((P < 0.05) r = 0.9). It was then concluded that fragment size greatly influenced the population and diversity of rodent species. It was recommended that the remaining large fragments in the study area should be protected by law from further fragmentation.

Keywords

Forest Fragmentation; Rodent Population; Abayum Forest; Cross River State; Nigeria

Conflicts of Interest

The authors declare no conflicts of interest.

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