Volume 50

The diet of the Vulnerable Yellow-bellied Glider (Petaurus australis unnamed subspecies) in north Queensland includes sap obtained from Eucalyptus resinifera (Small-fruited Red Mahogany), this being a critical resource obtained from a small percentage of trees. Past logging might have depleted resources for the gliders. In the Sawmill Gully area of Tumoulin Forest Reserve, an area temporarily reserved for the gliders, we show that most E. resinifera are less than 70 cm in diameter. Smaller size classes are all well-represented including saplings, but very few trees are greater than 1 m in diameter, suggesting that the forest is recovering from logging. Thirty-two glider sap-trees in the area had a mean diameter of 60.4 cm with a strong preference by gliders, relative to availability, for trees more than 60 cm in diameter. Recruitment of more E. resinifera to larger size classes may increase options for gliders, but more logging may deplete them.

Bowerbirds (Ptilonorhynchidae) are specialist frugivores, but consume invertebrates when breeding and occasionally feed on other plant material. Here I report observations of Tooth-billed Bowerbird (Scenopoeetes dentirostris) and Spotted Catbird (Ailuroedus maculosus) consuming flowers of Calliandra sp. (C. haematocephala), an ornamental introduced garden plant.

Jim Bravery (1896–1975) moved to the Atherton Tablelands in Queensland as a soldier-settler farmer in 1920. Already a birdwatcher, for the next 55 years he keenly observed and noted bird species, numbers and behaviour. In 1967 he recorded the first Sarus Cranes (Antigone a. gillae) on the Tablelands and in 1970 included Sarus Cranes and Brolgas (A. rubicunda) in his signature paper ‘Birds of the Atherton Shire, Queensland’ for the journal Emu. His unpublished writings, with other documents and historical observations, establish that Brolgas had colonised the recently-cleared farmlands of the Atherton Tablelands by at least 1920; that Brolga numbers were in the hundreds in the 1940s; and 1000 or more in the mid-1960s. They also suggest that in the early 1970s some 1500 cranes wintered on the central Atherton Tablelands at that time, mostly Brolgas, whereas today Sarus Cranes dominate the same area. Bravery’s observations underline the historical importance to Brolgas of woodland swamps south of Atherton, now largely drained and cleared, which may in part explain this major change in species distribution. In 1960 Bravery noted poisoning of Brolgas – the first historical evidence of persecution on the Tablelands – due to crop damage, which as a farmer he considered negligible. He maintained a keen interest in both crane species and believed that Sarus Cranes had been present but unnoticed on the Tablelands before 1967. In his last diary entry in June 1975, only weeks before his death aged 79, Bravery was deeply interested in reports of Brolga-Sarus hybrids and looked forward to news of further research.

Rainforests are one of the most diverse ecosystems in the world. In Australia, the Wet Tropics Rainforests of North Queensland are especially speciose, containing a wide range of flora and fauna, including a high number of endemic species. Unfortunately, the region has also been threatened by human impact such as land clearing. Relatively few studies have conducted full plot-level floristics in this region. In our study in the Gadgarra region of the Atherton Tablelands, Queensland, we looked at full floristics in 500m2 plots that we established in four vegetation types: a relatively undisturbed Old growth rainforest, an Old secondary rainforest (recovering from clearance since 1947); a Young secondary rainforest (recovering from clearance since 1972), and an Abandoned Orchard area. Across all plots, we found a total of 214 species belonging to 162 genera and 74 families. We found that the Old growth forest had the highest number of species, genera and families. The diversity present in the Older secondary plot was comparable to that displayed by the Old growth forest plot. In general, our results indicate that previously cleared forests have a lower species richness, a decrease in endemism, and altered species composition due to the effects of clearing. However, over time secondary succession results in some recovery of both forest structural and species composition similar to that of an undisturbed forest. Our study is descriptive in nature due to the lack of replication in sampling plots within vegetation types. However, we present a plant biodiversity list for each plot that can serve as baseline data for further studies in the region.

Fire management is a significant factor in the management of the endangered Black-throated Finch (Poephila cincta cincta). Patchy burning soon after wet season rain in Townsville woodlands was found to promote the diversity of grasses and herbs and their seeding, which is thought to provide significant habitat benefits for Black-throated Finches.

I report data on clutch size, nest size, the times taken to complete nesting stages and a description of nesting behaviours of 17 wild Johnstone River Snapping Turtles Elseya sp. based on observations spanning ten years. Clutch size ranged from 3 to 15 eggs, the nest opening was essentially circular (60 mm diameter), vertical nest depths ranged from 100 to 210 mm, egg laying times from 3 to 17 minutes, and nest filling-in times from 13 to 48 minutes. Excavation times were always the longest stage of the nesting process (> 1 hr), although few complete times were obtained. There was no relationship between clutch size and either egg-laying times nor nest filling-in times. A few nesting females used their knees (as well as the feet) to compact soil (n = 4) and also the plastron to flatten the soil surface during the filling in of nests (n = 3). Eggs with impact fractures were uncommon (6% of clutches) and in nearly all instances fractures were due to embedded stones in the wall of the egg chamber. I observed two instances where the entire nesting process was completed, including back-filling the nest, yet no eggs were laid.

Rose Gum (Eucalyptus grandis) is a tall, fast-growing eucalypt which, in north Queensland, occurs in upland wet sclerophyll forest. The tree provides important habitat for wildlife; in particular, large specimens provide hollows which are used as dens by the vulnerable Wet Tropics Yellow-bellied Glider (Petaurus australis unnamed subspecies). The Tumoulin Forest Reserve near Ravenshoe is home for both Rose Gum and the glider but has a history of logging such that large hollow trees are now scarce. Triggered by concern that den trees are vulnerable to fire and storm damage and might not be readily replaced, we investigated the diameter of Rose Gums in and around the Reserve along seventeen transects each with 20 trees. Rose Gum diameter varied strongly between transects but not with geology (basalt, rhyolite) nor position (edge, roadside, forest interior). Eight known den trees in the Reserve had a mean diameter of 151 cm and a minimum of 95 cm. Very few trees along transects matched these diameters but trees in the 50 to 100 cm diameter class – potential replacements den trees in the foreseeable future ­– were patchily dispersed and occasionally abundant. An assessment of Rose Gums at the scale of glider territories may be needed to ascertain prospects for the future development of den trees.

Emergence of nocturnal animals at dusk from daytime shelters may be influenced by caution with regard to predators as well as by foraging opportunity and weather. Yellow-bellied Gliders (Petaurus australis) are a nocturnal, arboreal marsupial that, in north Queensland, den in hollows predominantly in large Rose Gums (Eucalyptus grandis). We document emergence on 83 evenings in the Tumoulin and Gilbey Forests between Ravenshoe and Herberton. Dens were high in Rose Gums, twelve from a lateral spout and, unusually, one from a hole in the trunk. The first glider to emerge from a den did so from 22 minutes before to 31 minutes after End of Civil Twilight (the latter being 21–24 minutes after Sunset in the study area and approximating dusk), though most first emergences were from nine minutes before to eight minutes after. First emergence was not influenced by moonlight, season or den tree, but varied a little between glider groups. Groups of gliders sharing a den variously emerged in quick succession or up to eleven minutes later. We describe other behaviours associated with emergence. This tight pattern of emergence at dusk is in line with reports for the species in southern Australia, but we document for the first time a number of associated behaviours including infrequent calling from within the den.

Understanding patterns of habitat use by newborn-sized animals is critical to conserving threatened species and their potential nursery grounds. Giant Shovelnose Rays (Glaucostegus typus) are Critically Endangered but at least locally abundant in the Australian portion of their range, providing an opportunity in Australia to understand what types of habitat features are associated with newborn and young-of-the-year individuals in the absence of intense fishing pressure. To investigate this, we used replicated belt transects to study Giant Shovelnose habitat use and abundance in shallow (< 0.5 m), shoreline waters. 28 whole-island surveys were conducted at low tide over 2 years on Heron Island, Australia. In total, we counted 552 Giant Shovelnose Rays, 79% of which were newborn class (< 40 cm in length), in both sand flats and shallow areas with rock rubble. These habitat characteristics are consistent with other studies of Giant Shovelnose Rays in Australia, adding to the existing knowledge that these juvenile animals commonly use shallow waters. Studying newborn Giant Shovelnose habitat characteristics in a portion of their range where they are still locally abundant can offer a roadmap for managers to locate key regions to protect within imperiled portions of their range.