The role of native rodents in seed dispersal and seed predation of the Bunya Pine (Araucaria bidwillii)

The role of native rodents in seed dispersal and seed predation of the Bunya Pine (Araucaria bidwillii)

The bunya pine (A. bidwillii) has a very limited distribution within Australia. Part of the reason for this is likely to be its poor seed dispersal. Macropods, possums and rodents are known predators of both the seeds and tubers. However, there are no reported dispersal agents for A. bidwillii seeds. The aim of this research is to determine the extent to which A. bidwillii seeds are destroyed or dispersed by native rodents. Predation and dispersal of A. bidwilli seeds are being examined in southern Queensland in a small stand of A. bidwilli at Mt Mee, and in a larger stand at the Bunya Mountains and in northern New South wales in a similar habitat devoid of A. bidwilli near Queen Mary Falls. At each site, groups of 100 seeds are placed on the soil; 25 seeds are covered by wire mesh to exclude predators and 75 are left uncovered. Each seed is marked by a pink tag to assist in locating it and tracking its movement. Activity of rodents is monitored using CCD cameras connected to video-recorders. Hair tubes are also utilized for identification of rodents. Preliminary results indicate that a small but significant amount of seeds are eaten. However, enough seeds escape predation to produce seedlings. Germination is rapid under field conditions. Seeds were dispersed more than 16 m from their original locations, permitting some to germinate in
open sites away from the bunya pine canopy, where they are more likely to survive.

Abstract 77. Conference publication consists of only the abstracts of papers presented at the conference.