A comparative analysis of small mammal assemblages in and around Budongo Forest Reserve, Uganda.

Abstract

In this study of a comparative analysis of small mammal assemblages in and around Budongo Forest Reserve, there were three objectives; 1) to determine the habitat characteristics of the unlogged and logged compartments of Budongo Forest Reserve, Matrix habitat and Rwensama Forest Fragment, 2) to determine the diversity of small mammals in the unlogged and logged compartments of Budongo Forest Reserve, Matrix habitat and Rwensama Forest Fragment, and 3) to evaluate the response of small mammal species composition to habitat characteristics in the unlogged and logged compartments of Budongo Forest Reserve, Matrix habitat and Rwensama Forest Fragment. Small mammals were assessed using pitfall and snap traps in circular plots along transects. The habitat characteristics were assessed in all the plots established in all habitat types. The result showed that at least one habitat characteristic was different for at least two of the habitat types (P ≤ 0.001). Canopy openness, depth of organic matter and undergrowth density were highest in the Matrix, logged forest and Rwensama respectively. Species richness of seedlings, saplings and mature trees were highest in the Matrix, Rwensama and unlogged forest respectively. The diversity of seedlings, saplings and mature trees was highest in Rwensama forest fragment and lowest in the unlogged and logged forests and Matrix habitat respectively. Twenty one species of small mammals belonging to four families were recorded. Small mammal species richness predicted using Jaccknife 1 was; Matrix habitat (18), Rwensama (10), logged forest (7) and unlogged forest (6), implying that more species were recorded outside Budongo Forest Reserve than inside the continuous forest. Small mammal species diversity measured using Shannon Weiner diversity index was; Matrix habitat (2.02), Rwensama (1.88), logged forest (1.41) and unlogged forest (1.17), implying that the diversity of small mammals was highest outside than inside Budongo Forest Reserve. There was little separation of small mammals amongst the habitat types (R = 0.275, P ≤ 0.001) and no species was common to all habitat types. For all forest habitats Praomys jacksoni was the most abundant species while Mastomys hildebrandtii was the most abundant in the Matrix habitat. Small mammal species composition responded mainly to canopy openness and to a lesser extent to undergrowth density, diversity of saplings and mature trees, depth of organic matter and species richness of trees.