Small mammals were trapped in four rain forest fragments (3, 8, 20 and 97 ha), in an agricultural
landscape, and in comparable continuous tropical rain forest in north Queensland, Australia over 2 y. The most
frequently captured species were four murid rodents. Melomys cervinipes were captured in similar numbers in both
continuous and fragmented forest. This species achieves greatest abundance at forest edges and this study suggests
that edges of fragments and edges of continuous forest will support similar densities. Abundance of Uromys
caudimaculatus was positively correlated with size of fragment and peaked in continuous forest. This species had a home range
larger than the smaller fragments and was thus disadvantaged but its ability to utilize the agricultural matrix between
fragments mitigated the effect. Rattus leucopus and R. fuscipes were most abundant in fragments and continuous forest
respectively but both species occurred in similar abundance in the 97-ha fragment. This suggests their population size
is related to habitat rather than competitive exclusion as previously postulated. Ordination of the populations of the
nine most commonly captured mammals, separated the fragment and continuous sites but placed the largest fragment
closest to the continuous sites. The contrasting response of the two Rattus spp. was the primary influence on the
ordination. Second in importance was Trichosurus vulpecula, a folivorous possum, which was absent from the
continuous sites. The fragments may have had more nutrient-rich, pioneer tree foliage than continuous forest. Isoodon
macrourus, Perameles nasuta, Antechinus godmani and Uromys hadrourus also showed positive or negative response to
fragmentation. Species utilizing the matrix between forest fragments and species adapted to forest edge are advantaged
by the fragmentation process whereas forest specialists tend to extinction in fragments, particularly where the home
range of the animal is not many times smaller than the fragment.
SPATIAL SCALE, SPECIES DIVERSITY, AND HABITAT STRUCTURE: SMALL MAMMALS IN AUSTRALIAN TROPICAL RAIN FOREST