Are the marsupials restricted to high elevation forests because of predation?
John thought that one of the factors causing this distribution could be pressure from predation. The rufous owl, a specialist predator of arboreal vertebrates, was generally thought to be common only in lowland forests in the region, and predation by the owl could be responsible for restricting the possums to higherelevation forests. However, surveys conducted in his study found that the rufous owl was relatively common in high elevation forests of the study area. These results are sufficient to refute the notion that predation by the owl restricts possums to higher elevation forests in north-east Queensland. Above.. Lumoltz tree kangaroo (Dendrolagus lumholtzi) Photo: Frith/Cianelli Below: Green ringtail possum (Pseudocheirops archeri) What about food quality? Foliage is a poor quality food, low in protein and often rich in toxins, and folivorous mammals are very sensitive to foliage ‘quality’. John expected that leaf chemistry would explain the distribution of folivorous marsupials i
