Temporal and spatial dynamics of small terrestrial mammals inhabiting a
degradation gradient in a lowland tropical forest in Uganda
Abstract
A study aimed at assessing the structure of rodent and shrew assemblages
inhabiting a degradation gradient while considering rainfall patterns,
was conducted in one of few remaining lowland tropical forests in
Eastern Africa. We collected a unique dataset of rodents and shrews,
representing 24 species (19 rodents, 5 shrews). The most abundant
species alternated in dominance as species abundance significantly
fluctuated across the study period following a degradation gradient
(F2,33 = 5.68, p = 0.007). While only generalist species were observed
near the degraded forest edge, habitat specialists such as Deomys
ferrugineus, Malacomys longipes and Scutisorex congicus, were observed
in the primary forest interior suggesting a significant (X2 = 1165.329,
P<0.001) association between species and their associated
habitats and habitat attributes. There was also an observed correlation
between rainfall patterns and species abundance. Capturing more species
in adjacent fallows and along the degraded forest edge suggests that
many species are able to live in degraded habitats that offer a variety
of food resources. The continued pressure on forest resources, however,
may lead to changes in habitat structure. This, coupled with the
dependence of forest ecological functions on rainfall, which is
typically not the case, may ultimately cause the local extinction of
highly specialized but less adaptable species.