Evidence for gradual retreat of dry monsoon forests under a regime of Aboriginal burning, Karslake Peninsula, Melville Island, northern Australia

Karslake Peninsula is a flat laterite area on the north coast of Melville Island. In 1968 a small patch of monsoon forest surrounded by tall eucalypt savanna was identified in a detailed vegetation map of the Peninsula. The eucalypt savanna is burnt annually by Aborigines to facilitate marsupial hunting. Twenty-two years later this patch was revisited and was found to occupy roughly the same area. Permanent transects of its boundary revealed that grass had not invaded the patch over three dry seasons from 1988 to 1990. Only one tree was noted as having been killed by fire on the boundary during this period. It is concluded that at this site a formerly extensive dry monsoon forest is being very gradually converted into savanna through patch fragmentation.