
%0 Journal Article
%A M. Jackson, Stephen 
%T Preliminary predictions of the impacts of habitat area and catastrophes on the viability of Mahogany Glider Petaurus gracilis populations
%J Pacific Conservation Biology
%D 1999/03/10
%V 5
%N 1
%P 56-62
%K 
%R https://doi.org/10.1071/PC990056
%U https://www.publish.csiro.au/paper/PC990056 
%X The population viability analysis (PVA) program VORTEX was used to examine the viability of different sized populations of the Mahogany Glider Petaurus gracilis, and to examine the impact of a one in a hundred year catastrophe (each requiring a different reserve size) of different severities on different sized populations. The PVA showed that populations up to 300 individuals (1 500 ha) have a negative population growth rate, high losses of genetic diversity and a greater than 5% chance of extinction within 100 years. Populations of 400?700 individuals (2 000?3 500 ha) showed a decreasing trend in population size suggesting they are likely to become extinct after 100 years. A population of 800 individuals (4 000 ha) was needed for the population size to stabilize. Sensitivity analysis showed adult mortality of greater than 25% to be important in decreasing the viability of populations. Populations of 400 were resistant to a one in 100 year catastrophe which had a 20% mortality and 20% decrease in reproduction. When the mortality was 70%, with 70% decrease in reproduction, a population of 1 000 still had a 12% chance of extinction. As only approximately 50% of the available habitat appears to be occupied, an area up to 8 000 ha (800 individuals) is suggested to be required to maintain viable populations of Mahogany Gliders. A number of management options are recommended including the retention of habitat, establishing corridors between key populations, and using fire to minimize rainforest expansion. 
