Suchergebnisse

The ecological factors controlling the distribution and abundance of the
folivorous marsupials endemic to the rainforests of northern Australia are not
understood. In this study, we surveyed folivore abundance at 40 sites
stratified by altitude and geology in rainforests of the Atherton Tableland,
north Queensland. All five species of folivore that inhabit the study area
were more abundant in highland (800–1200 m) than in upland
(400–800 m) forests. Allowing for the effects of altitude, four species
of folivore were more abundant in forests on nutrient-rich basalts than in
forests on nutrient-poor acid igneous or metamorphic rocks. The abundance of
two folivore species also varied inversely with rainfall. Altitudinal
variation in folivore abundance in the study area has been attributed to
habitat destruction, Aboriginal hunting, the distribution of host plants and
climate; however, none of these hypotheses has been tested. Variation in
folivore abundance with geology is plausibly explained as a response to the
nutritional quality of foliage. Foliage quality may also explain the inverse
relationship between two of the folivores and rainfall. The results of this
study show that only a relatively small proportion of north Queensland
rainforests support abundant populations of the endemic folivorous marsupials.