Aerial and ground survey of sap trees of the yellow-bellied glider (Petaurus australis reginae) near Atherton, North Queensland

Sap-feed trees of the yellow-bellied glider (Petaurus australis reginae) we re located in a 1600-ha site in north Queensland by aerial survey and groun d survey. The ground survey located 77 active sap-feed trees, of which only seven were seen from the air. Thus we conclude that aerial survey is not a reliable means of censusing yellow-bellied glider populations. Sap-feeding scars made by gliders were found only on Eucalyptus resinifera even though four other species of Eucalyptus, which are used for sap-feeding in New So uth Wales, were also present in the area. In addition to the active feed tr ees, we found 156 trees with old sap-feeding scars, giving a total of 233 s carred trees in all. All but two of these were located within 500 m of matu re E. grandis trees, which are believed to be the prime source of glider de ns. Of the E. resinifera trees with diameter at breast height greater than 40 cm in the study area 1.06% were scarred and 0.35% were in active use by the gliders. The sap-feed trees had significantly fewer other trees in thei r immediate vicinity than the mean for all E. resinifera trees in the study area. The early stages of rainforest invasion investigated here did not in dicate a reduction in use for sap-feeding by gliders. However, in the long- term E. resinifera is unable to thrive or reproduce within a rainforest, su ggesting that the gliders' habitat will be reduced as the E. resinifera tre es die out.