The honey possum, Tarsipes rostratus, is a unique marsupial in several respects, from its smallest size at birth to its fully nectarivorous diet. A striking feature is the degree of reduction of its teeth, with fewer, smaller teeth in its jaws than for any other marsupial. The few peg-like teeth of honey possums cannot be clearly differentiated into premolars or molars. Here we used a developmental series of 21 honey possums, ranging in size from 2.8 to 30 mm head length, to uncover the identities of the postcanine teeth. We used histology, diceCT microCT and synchrotron microCT to find developing tooth buds and mineralising teeth. We found that there are up to two deciduous premolars in each quadrant, with between zero and two molars behind the deciduous premolars. In addition, there is no evidence of tooth replacement events at any locus. This confirms that the honey possum is one of the most extreme cases of tooth reduction in marsupials, even though it retains long lower incisors and an exceptionally long tongue to support its nectar-feeding habit.
In the past 200 years, mammal declines in Australia have far exceeded those observed anywhere else in the world. The catalysts for these declines are primarily introduced predators and land-use changes. Mammals have declined most in the arid zones of Australia and least in areas of higher rainfall. One contemporary solution for conserving Australia’s threatened species is to create predator-free islands or fenced areas which act as safe-havens for both threatened reintroduced species and existing species already present in the environment. Here, we investigated the effects that a safe-haven has on small mammals (<200 g) in tall forest at Barrington Tops at an elevation of 1300 m. We assessed small mammal assemblages and ground cover vegetation inside and outside the safe-haven in comparable habitats. The abundances of Antechinus stuartii and particularly Rattus lutreolus were greater inside the safe-haven; surprisingly, Rattus lutreolus was rarely captured outside of the safe-haven. Vegetation cover below waist-height (100–120 cm) was much denser inside the fenced area than outside. Our findings are significant because they showed that two native small mammal populations at Barrington Tops have benefited from the exclusion of introduced predators and large herbivores even though their conservation status is least concern. Our findings have implications for efforts to conserve native mammals because they provide insights into the extent to which small mammals, particularly native rodents, may have declined in the forests of south-eastern Australia and highlight that our understanding of the threats posed to their conservation status is under-appreciated.
Monitoring populations of flying-foxes is challenging considering their nomadic habits but is needed for conservation status assessments and tracking movement trends to inform management issues. National censuses involving synchronous counts at as many flying-fox roosts as possible have been undertaken, including into the present day with the National Flying-fox Monitoring Program. Established in 2012, this program involves quarterly censuses in the months of February, May, August and November. This paper focuses on how the program is operating in New South Wales, where there are currently 476 known roosts. As of March 2026, 52% of known roosts are assigned to participant/s, up from 35% in 2019, which is monumental considering the state’s number of known roosts increased by 41% over the same timeframe. Land managers contribute to the largest proportion of coverage, followed by New South Wales Department of Climate Change, Energy, the Environment and Water staff and wildlife rehabilitators. The major coverage gaps assessed at a local government area level were unassigned roosts in seven local government areas situated in the Northern Rivers, Mid North Coast and Far South Coast regions. New technological innovations using weather radar and drone-acquired thermal orthomosaics are being explored by scientists to help fill coverage gaps. In addition, the Australian Flying-fox Monitor, an online platform launched in July 2025, is helping to streamline data submission and display data in real-time, which will be necessary for handling larger datasets into the future in line with the goal of having coverage closer to 100% of roosts. To that end, we are appealing for new roost monitoring participants, especially from areas with major coverage gaps.
The establishment of the Drysdale River Mission, near Kalumburu, Western Australia, in 1908 facilitated the early collection and documentation of the local mammal fauna and the Indigenous Knowledge associated with it. This review examines evidence of chronological changes in the historic status and range of Critical Weight Range (CWR) mammals in the study area (defined by a 45 km radius around Kalumburu) in the northern limit of the Mitchell subregion of the North Kimberley Bioregion, by comparing historic data with more recent data. It concludes that at least 27 species of CWR mammals occurred there, consistent with the wider hotspot. Of these species, several have apparently suffered local extinction or declines matching trends reported elsewhere in the region and across northern Australia. Two arboreal species (Brush-tailed Rabbit-rat Conilurus penicillatus and Golden-backed Tree-rat Mesembriomys macrurus) and a medium-sized ground-dwelling species (likely Spectacled Hare-wallaby Lagorchestes conspicillatus) disappeared in the early 1900s. A further five species persisted to the 1980s but are now likely to be locally extinct including Golden Bandicoot Isoodon auratus, Brush-tailed Phascogale Phascogale tapoatafa, Brush-tailed Possum Trichosurus vulpecula, Black-footed Tree-rat Mesembriomys gouldi and Savanna Glider Petaurus ariel. Another four species have experienced local declines and have disappeared from parts of the study area (Northern Quoll Dasyurus hallucatus, Nabarlek Petrogale concinna, Grassland Melomys Melomys burtoni and Northern Brown Bandicoot Isoodon macrourus). The study shows that the Biodiversity Hotspot is not immune to factors that have caused CWR mammals to decline in northern savannas and adds new knowledge to a poorly studied region of Australia.
Behavioural strategies used by wildlife to mitigate thermal stress are at the forefront of ecological research as the frequency, severity, and geographic range of extreme heat increase. On 27 January 2026, grey-headed flying-foxes (Pteropus poliocephalus) were monitored from the banks of the Yarra River in Melbourne, Victoria, Australia, where the maximum air temperature reached 40.7°C. An adult flying-fox belly-dipped into the river, saturating its ventral fur before landing in a tree overhanging the river; here it proceeded to drink the water off its saturated fur. This adult bat was joined by a smaller conspecific which licked the wetted bats fur for over a minute. This research note describes an apparent water-sharing behaviour and considers whether this interaction may represent a previously undescribed social mechanism that facilitates access to water during extreme heat, particularly for vulnerable individuals.
