Petaurus Norfolcensis Research Articles

Will arboreal mammals use rope-bridges across a highway in eastern Australia?

Artificial structures designed to promote road-crossing by arboreal mammals are increasingly being installed in Australia but there is a limited understanding of their usefulness. We studied five 50–70-m-long rope-bridges (encompassing three designs) erected across the Pacific Highway, a major freeway in eastern Australia. Native arboreal mammals showed a willingness to explore these structures, being detected by camera traps on four rope-bridges. The vulnerable squirrel glider (Petaurus norfolcensis) crossed on one rope-bridge at least once every 4.5 weeks over a 32-week period. The feathertail glider (Acrobates pygmaeus), common ringtail possum (Pseudocheirus peregrinus) and the common brushtail possum (Trichosurus vulpecula) were detected on one of two rope-bridges that extended under the freeway at creek crossings. The feathertail glider was detected on all three rope-bridge designs. Our results suggest that rope-bridges have the potential to restore habitat connectivity disrupted by roads for some arboreal mammals. Further research is needed to refine the design and placement of rope-bridges as well as to determine whether these structures promote gene flow.

Influence of urban edges on stress in an arboreal mammal: a case study of squirrel gliders in southeast Queensland, Australia

There is growing recognition that ecological research must expand its focus beyond inference based on pattern-process relationships to the direct measurement of ecological and physiological processes. Physiological assessment is important because vertebrates cope with unpredictable and noxious stimuli by initiating a stress response. However, an over-activation of the acute stress response by numerous novel and potentially stressful anthropogenic pressures, including those associated with urban edges, has the potential to generate chronic stress and a greater susceptibility to disease, reduce fecundity and survivorship. An individual’s physiological response to edge habitats with varying degrees of contrast to the adjacent disturbed urban matrix (e.g. major vs. minor roads), may provide insight into their survival likelihood in fragmented urban landscapes. Although demographic changes in wildlife resulting from urbanization have been documented, only recently have physiological consequences been examined. We addressed this problem using a case study of the squirrel glider (Petaurus norfolcensis) in the fragmented urban landscape of southeast Queensland, Australia. Hair samples were used to enable a comparison of hair cortisol levels in individual squirrel gliders, providing an indication of potential stress. We applied a linear mixed-effect modeling approach clustered by patch to quantify the influence of site-level habitat factors and relative abundance comparative to edge contrast on hair cortisol levels. We found that edge type had a strong positive effect on hair cortisol levels; but this depended on the availability of abundant nest hollows at a site. We conclude that individual hair cortisol concentration, providing an index of stress, was lowest in interior habitats and highest in edge habitats adjacent to major roads. Furthermore, gliders occupying low edge contrast habitats adjacent to residential areas and minor roads, and containing abundant tree nest hollows, had low-moderate hair cortisol levels. This highlights the potential importance of these habitats for the conservation of arboreal mammals such as the squirrel glider in urban landscapes.

Use and characteristics of nocturnal habitats of the squirrel glider (Petaurus norfocensis) in Australian temperate woodlands

In Australian temperate woodlands, most squirrel glider (Petaurus norfolcensis) habitats exist outside formal conservation reserves, often in highly fragmented agricultural landscapes. To conserve squirrel glider populations in such woodlands it is essential to define important habitats and understand how they are used. This study examines the nocturnal habitat use of squirrel gliders across five sites within an agricultural landscape in south-eastern Australia. Over a five-month period we radio-tracked 32 gliders to 372 nocturnal locations. We quantify characteristics of key nocturnal habitats and describe their use. Gliders were more likely to use large eucalypt trees, particularly yellow box (Eucalyptus melliodora) and mugga ironbark (E. sideroxylon). Nocturnal activity mostly took place high in the canopy of eucalypts, accounting for 74% of fixes. Multiple regression models revealed that feeding was more likely to occur in large, healthy trees close to drainage lines, with a preference for E. melliodora, when eucalypts were not flowering. Flowering trees were preferentially sought and were strongly associated with being large healthy trees that occur on ridges and upper slopes. Showing that the squirrel glider utilises key feeding structures (large healthy Eucalyptus trees) in different parts of the landscape at different times has direct management implications in the conservation and restoration of squirrel glider habitat, particularly in fragmented temperate woodland.

Facilitated movement over major roads is required to minimise extinction risk in an urban metapopulation of a gliding mammal

Context Urbanisation is recognised as a primary cause of biodiversity loss. Roads are an inherent element of this, creating partial or complete barriers to animal movement. Urban landscapes of eastern Australia are typified by a dense road network interspersed with remnant patches of bushland. Inter-patch movement by tree-dependent gliding mammals may be halted and, consequently, population viability threatened, when canopy gaps over roads exceed gliding ability. Aims We test the notion that a metapopulation of the squirrel glider (Petaurus norfolcensis) in southern Brisbane can persist within a highly fragmented urban landscape with large road canopy gaps. Methods We used the population modelling software VORTEX to investigate the influence of inter-patch movement (dispersal) and wildfire on the probability of extinction. Wildfire is an inherent characteristic of this landscape. Key results Our modelling suggests that a lack of inter-patch movement as a result of road barriers, in tandem with wildfire, is associated with a high probability of local extinction. However, a small rate of inter-patch movement can substantially reduce the likelihood of extinction. Conclusions Road-crossing structures are the most plausible means available to link remnants to enable inter-patch movement for squirrel gliders in this landscape because of inadequate road-side tree height. Simulation studies such as the present study that test population viability are critical to convince land managers that action must be taken. Implications The need to conserve urban biodiversity will increase over time, so land managers must consider the likely benefits to population persistence conferred by installing wildlife crossing structures into existing roads.

Restoring Connectivity in Landscapes Fragmented by Major Roads: A Case Study Using Wooden Poles as “Stepping Stones” for Gliding Mammals

Tree‐dwelling mammals may be vulnerable to road mortality if forced to cross canopy gaps on the ground. This group of mammals has received scant attention worldwide despite major road projects potentially causing severe fragmentation to their habitat. Gliding mammals may be enabled to cross road gaps that exceed their gliding capability by the installation of tall wooden poles to act as “stepping stones.” We investigated whether such glide poles installed across two land‐bridges in eastern Australia could restore landscape connectivity for small gliding petaurid marsupials. Hair‐traps revealed repeated use of all poles at both locations over periods of 1–3 years. Camera traps at one site suggest a crossing frequency on the poles by the squirrel glider (Petaurus norfolcensis) of once every 3.8 nights. Radio‐tracked animals did not glide directly over the road but instead used the poles to cross on the bridge. Hair‐traps and camera traps installed within the middle of two reference land‐bridges that lacked glide poles failed to detect crossings by gliding mammals despite their presence in adjacent forest. These observations suggest that glide poles can facilitate road crossing and thereby restore habitat connectivity for gliding mammals. This lends support to the notion that glide poles have the potential to mitigate road‐induced habitat fragmentation for gliding mammals worldwide.

Degree of Landscape Fragmentation Influences Genetic Isolation among Populations of a Gliding Mammal

Forests and woodlands are under continuing pressure from urban and agricultural development. Tree-dependent mammals that rarely venture to the ground are likely to be highly sensitive to forest fragmentation. The Australian squirrel glider (Petaurus norfolcensis) provides an excellent case study to examine genetic (functional) connectivity among populations. It has an extensive range that occurs in a wide band along the east coast. However, its forest and woodland habitat has become greatly reduced in area and is severely fragmented within the southern inland part of the species' range, where it is recognised as threatened. Within central and northern coastal regions, habitat is much more intact and we thus hypothesise that genetic connectivity will be greater in this region than in the south. To test this we employed microsatellite analysis in a molecular population biology approach. Most sampling locations in the highly modified south showed signatures of genetic isolation. In contrast, a high level of genetic connectivity was inferred among most sampled populations in the more intact habitat of the coastal region, with samples collected 1400 km apart having similar genetic cluster membership. Nonetheless, some coastal populations associated with urbanisation and agriculture are genetically isolated, suggesting the historic pattern observed in the south is emerging on the coast. Our study demonstrates that massive landscape changes following European settlement have had substantial impacts on levels of connectivity among squirrel glider populations, as predicted on the basis of the species' ecology. This suggests that landscape planning and management in the south should be focused on restoring habitat connectivity where feasible, while along the coast, existing habitat connectivity must be maintained and recent losses restored. Molecular population biology approaches provide a ready means for identifying fragmentation effects on a species at multiple scales. Such studies are required to examine the generality of our findings for other tree-dependent species.

Squirrel glider home ranges near urban edges in eastern Australia

AbstractConservation biology and landscape ecology are increasingly concerned with the effects of urbanization on wildlife, including the influences of habitat edges. This is particularly important in landscapes where a restriction on species home‐range movements may reduce an animal's ability to access habitat resources, which ultimately reduces population viability. Despite this, there is limited information available on the movement behavior of wildlife at forest edges adjoining urban areas. We addressed this by radiotracking 30 squirrel gliders Petaurus norfolcensis in forest interiors and near road and residential edges in the fragmented urban landscape of south‐east Queensland, Australia. An assessment of fixed‐kernel (FK100% and FK50%) and minimum convex polygon (MCP100%) methods revealed that FK provided the most reliable home‐range estimates. We applied a general linear model to test the influence of season, age and sex relative to habitat type (forest interiors, road edge, residential edge) on squirrel glider home‐range size (FK95% & FK50%). We found that squirrel gliders living in interior habitats had significantly larger home ranges (7.07 ha±0.43) than individuals living near roads (3.79 ha±0.22) and residential areas (3.40 ha±0.26). Similarly, home‐range core areas (FK50%) were significantly larger in forest interiors (1.49±0.13 ha) than near road (0.78±0.07 ha) and residential edges (0.70±0.08 ha). We also found that squirrel gliders regularly cross narrow roads up to 20 m wide and with a tree gap up to 15 m to access adjacent vegetation, and are willing to utilize foraging resources in residential backyards. Changes in squirrel glider home ranges near edges identified in this study have implications for understanding how this species responds to urban edges, and we highlight important areas for future edge‐related studies to correctly inform conservation and management.

Den trees, hollow-bearing trees and nest boxes: management of squirrel glider (Petaurus norfolcensis) nest sites in tropical Australian woodland

The squirrel glider (Petaurus norfolcensis) is an arboreal marsupial potentially impacted throughout its geographic range by the loss of hollow-bearing trees. We investigated the use of den trees and the availability of hollow-bearing trees near Mackay in the tropical north of the squirrel glider range where information was deficient. Mean den tree size (41.1 ± 2.9 cm (s.e.), diameter at breast height (dbh)) was significantly larger than that of available trees (27.5 ± 0.9 cm). Dead trees (stags) comprised 52% of 27 dens but comprised only 12% of available trees. This likely reflects the greater frequency of hollows in dead trees compared with other trees. Surveys found that 59% of 720 available trees contained hollows. A much lower percentage of trees in the 10–30-cm dbh size class were hollow-bearing (22%) compared with trees >30 cm (77%), and we view these smaller trees as those providing future den trees. Their density varied from 17 to 95 ha–1 among sites, which suggests that most sites have an adequate supply of future hollows. We installed 56 nest boxes to determine use by squirrel gliders. Only 20% were used after 3 years, but use was not influenced by the availability of tree hollows. Tree hollow availability appears adequate for the squirrel glider in these tropical woodlands but further studies are needed to understand the dynamic processes that govern this resource.

Wooden poles can provide habitat connectivity for a gliding mammal

Gliding mammals may be susceptible to habitat fragmentation due to increased vulnerability to predators and road mortality if forced to cross roads and other canopy gaps on the ground. We document three trials where 6–12-m-high wooden poles, also known as glide poles, were installed to provide a link for gliding mammals across 50–75-m-wide canopy gaps, over open pasture or over roads. We used hair-traps over periods of 10–42 months to determine whether squirrel gliders (Petaurus norfolcensis) used the poles. Squirrel glider hair was detected on at least one pole during 69–100% of sampling sessions. At two road locations where poles were installed on wildlife land-bridges, hair was detected on poles in the middle of the bridge in 7–18 sessions, suggesting that complete crossings may have occurred. At one road location a camera-trap recorded a squirrel glider ascending a middle pole on five of 20 nights. Repeated use of the wooden poles by squirrel gliders at three locations suggests that tall wooden poles can restore habitat connectivity for a gliding mammal. We recommend further trials to extend our knowledge of the usefulness of this management tool for a range of gliding mammal species.

The distribution and density of the squirrel glider (Petaurus Norfolcensis) on islands in southeast Queensland

The distribution and density of the squirrel glider (Petaurus Norfolcensis) on islands in southeast Queensland

Threatened populations of the Australian squirrel glider (Petaurus norfolcensis) show evidence of evolutionary distinctiveness on a Late Pleistocene timescale

The squirrel glider Petaurus norfolcensis occurs across a broad Australian latitudinal range that includes gaps in distribution and potential biogeographic barriers, creating the potential for evolution of distinct entities within this species. Because of the species’ threatened status in the southern part of its range, we tested for the presence of geographically based independent evolutionary units among gliders sampled from southern, and northern coastal populations, using sequences of mitochondrial cytochrome b DNA (mtDNA) and a set of five nuclear microsatellites in 258 individuals. Our analyses suggest that an initial northward colonisation in the early- to mid-Pleistocene was followed by isolation by distance and, eventually, divergence between the sampled coastal and southern populations in the mid- to late-Pleistocene. We propose that the previously large and diverse southern populations have declined coincidentally with the replacement of wet forests by open sclerophyll woodlands during the preceding few million years. By contrast coastal populations further north appear to have been expanding and at present have an effective population size several times greater than southern populations. These results suggest that the two forms are on different evolutionary trajectories and should be treated separately for conservation purposes. It is highly desirable that loss of southern populations be prevented to maintain the unique genetic diversity accumulated over a considerable evolutionary timescale.

Change in habitat resources and structure near urban edges and its influence on the squirrel glider (Petaurus norfolcensis) in southeast Queensland, Australia

AbstractUrban landscapes often expose wildlife populations to enhanced edge effects where the biotic and abiotic attributes of native ecosystems have been significantly altered. While some species may respond favourably to edges, there are likely to be varying negative consequences for many forest‐dependent species. In particular, marsupial gliders are influenced by changes in forest composition and structure near edges due to highly specific feeding and nesting requirements, and a high reliance on tree cover to traverse a landscape. We addressed this problem using the squirrel glider (Petaurus norfolcensis) in the fragmented urban landscape of southeast Queensland, Australia. Analysis of variance was applied to determine differences in habitat resources and structure in relation to glider presence and trap success rates in forest fragment interiors compared with road (minor & major) and residential edge habitats. We postulate that an increased presence of squirrel gliders in sites adjacent to minor road and residential edges may be due to the availability of additional resources and/or varying dispersal opportunities. Conversely, forest fragment interiors contain a higher abundance of nest hollows and large trees, together with a greater floristic species richness providing more reliable seasonal foraging sources, which may explain the greater trap success rates of squirrel gliders in these sites. We conclude that while forest fragment interiors provide habitat suitable for year‐round use by greater numbers of squirrel gliders, the conservation value of some edge habitats that provide additional resources and dispersal opportunities should not be underestimated for forest‐dependent mammals; however, each edge type must be assessed individually.

A Voronoi diagram based population model for social species of wildlife

A population model is presented that accounts for spatial structure within habitat patches. It is designed for social species of wildlife that form social group home ranges that are much smaller than patch size. The model represents social group home ranges by Voronoi regions that tessellate a patch to form a Voronoi diagram. Neighbouring social groups are linked with habitat-confined shortest paths and form a dispersal network. The model simulates population dynamics and makes use of Voronoi diagrams and dispersal networks as a spatial component. It then produces density maps as outputs. These are maps that show predicted animal densities across the patches of a landscape. A construction procedure for the particular Voronoi diagram type used by the model is described. As a test case, the model is run for the squirrel glider ( Petaurus norfolcensis), a small arboreal marsupial native to Australia. A time series of density maps are produced that show squirrel glider density changing across a landscape through time.

Evidence that a Highway Reduces Apparent Survival Rates of Squirrel Gliders

Roads and traffic are prominent components of most landscapes throughout the world, and their negative effects on the natural environment can extend for hundreds or thousands of meters beyond the road. These effects include mortality of wildlife due to collisions with vehicles, pollution of soil and air, modification of wildlife behavior in response to noise, creation of barriers to wildlife movement, and establishment of dispersal conduits for some plant and animal species. In southeast Australia, much of the remaining habitat for the squirrel glider, Petaurus norfolcensis, is located in narrow strips of Eucalyptus woodland that is adjacent to roads and streams, as well as in small patches of woodland vegetation that is farther from roads. We evaluated the effect of traffic volume on squirrel gliders by estimating apparent annual survival rates of adults along the Hume Freeway and nearby low-traffic-volume roads. We surveyed populations of squirrel gliders by trapping them over 2.5 years, and combined these data with prior information on apparent survival rates in populations located away from freeways to model the ratio of apparent annual survival rates in both site types. The apparent annual survival rate of adult squirrel gliders living along the Hume Freeway was estimated to be approximately 60% lower than for squirrel gliders living near local roads. The cause of the reduced apparent survival rate may be due to higher rates of mortality and/or higher emigration rates adjacent to the Hume Freeway compared with populations near smaller country roads. Management options for population persistence will be influenced by which of these factors is the primary cause of a reduced apparent survival rate. © 2010 by the author(s).

The use of den trees by the squirrel glider (Petaurus norfolcensis) in temperate Australian woodlands

Effective conservation relies on understanding the biology of particular species and how they use key resources. For many arboreal mammals, tree hollows are a key den site. We examined the use of tree hollows by the squirrel glider (Petaurus norfolcensis) in south-eastern Australia. Over a five-month study, individual squirrel gliders used multiple hollow trees (average = 7) as den sites. Den sites were often adjacent to areas where nocturnal activities took place. The average distance between den sites used by individual gliders on successive days was 218 m. Dens were often shared by an adult pair and a juvenile. Den trees were disproportionably used, with gliders showing preference for 1–2 primary den trees often located on steep slopes. Our findings have implications for the number and spatial arrangement of den trees needed to promote the conservation of populations of the squirrel glider, particularly where land is used for agriculture and livestock grazing.

Variation in the home-range size of the squirrel glider (Petaurus norfolcensis)

The home-range area of animals may vary geographically and in response to habitat quality. We investigated the size of squirrel glider (Petaurus norfolcensis) home ranges near Brisbane, Queensland, and at Tea Gardens on the central coast of New South Wales. Habitat at both sites had been partially cleared and had been subjected to grazing for several decades. Twelve gliders were tracked over an average of 3.5 months in Brisbane. The fixed kernel (FK95%) home-range estimate averaged 4.6 ± 0.7 (s.e.) ha while the minimum convex polygon (MCP100%) averaged 6.7 ± 1.5 ha. Six gliders were tracked over 1 month at Tea Gardens. The FK95% home-range estimate averaged 14.8 ± 2.4 ha while the MCP100% averaged 13.3 ± 3.1 ha. The Tea Gardens values are derived from relatively short periods and are likely to underestimate the areas used. This study demonstrates that home-range size can vary substantially in the squirrel glider. This has implications for understanding how this species responds to variation in habitat quality and highlights the need for site-specific studies to inform aspects of management.

Population ecology of the nectar-feeding squirrel glider (Petaurus norfolcensis) in remnant forest in subtropical Australia

Context. Nectar is a temporally variable food resource. However, because few studies describe the population dynamics of nectar-feeding non-flying mammals, it is unclear how such populations are influenced by resource availability. Aims. We investigated the population ecology of the squirrel glider (Petaurus norfolcensis) in remnant forest in Brisbane, Australia, where nectar was a dominant food item. Methods. We used 36 tree-mounted traps to census a squirrel glider population inhabiting a 47-ha urban remnant over a 4-year period. Key results. A total of 201 gliders was captured 705 times in 3729 trap-nights (19% trap success). Population density peaked in the first year at ~1.6 individuals ha–1, and declined down to ~0.5 individuals ha–1 by the final year. This change in population density appeared to be mediated by annual variation in flowering intensity. Births occurred from March to November, peaking between April and July. All females >1 year old bred in each year of the study, with a mean litter size of 1.7 (n = 122). The overall natality rate was 1.9, indicating that females occasionally bred twice per year. The sex ratio was at parity in the pouch and in the trappable population. Gliders first entered the trappable population at 4 months of age, and persisted for a mean of 32 months. The maximum longevity was at least 6 years. Conclusions. The demographic characteristics of this squirrel glider population within remnant forest surrounded by urban development were similar to those reported elsewhere. Variation in nectar availability appears to have a substantial influence on the dynamics of squirrel glider populations. Implications. The substantial variation in population size driven by food availability raises concerns regarding the viability of small populations of nectarivorous non-flying mammals inhabiting remnant habitat.

Large Gaps in Canopy Reduce Road Crossing by a Gliding Mammal

Roads and traffic reduce landscape connectivity and increase rates of mortality for many species of wildlife. Species that glide from tree to tree may be strongly affected by roads and traffic if the size of the gap between trees exceeds their gliding capability. Not only are wide roads likely to reduce crossing rates, but mortality may also be increased if gliders that do cross have poor landing opportunities. The road-crossing behavior of 47 squirrel gliders (Petaurus norfolcensis) was investigated in southeast Australia using radio-tracking. The proportion of gliders crossing one or both roadways of a freeway where trees were present or absent from the center median was compared to that at single-lane country roads (control). The proportion of gliders crossing the road at control sites (77%) was similar to the proportion that crossed one or both roadways at the freeway with trees in the median (67%), whereas only a single male (6%) crossed the freeway where trees were absent from the median. The frequency of crossing for each individual was also similar at control sites and freeway sites with trees in the median. The almost complete lack of crossing at sites where trees were absent from the median was attributed to the wider gap in canopy (50 – 64 m vs. 5 – 13 m at sites with trees in the median). This suggests that traffic volume, up to 5,000 vehicles per day on each roadway, and the other characteristics of the freeway that the authors studied are not in themselves complete deterrents to road crossing by squirrel gliders. This study demonstrates that retaining and facilitating the growth of tall trees in the center median of two-way roads may mitigate the barrier effect of roads on gliders, thus contributing positively to mobility and potentially to connectivity. This information will be essential for the assessment of road impacts on gliding species using population viability models.

Influence of contrasting urban edges on the abundance of arboreal mammals: A study of squirrel gliders ( Petaurus norfolcensis) in southeast Queensland, Australia

The primary impacts of urban development on biodiversity are loss and fragmentation of habitat, and changes in the structure, composition and function of remnant native ecosystems. Forest dependent species, including arboreal mammals, are particularly sensitive to these changes due to their highly specific habitat requirements and inability or reluctance to cross the urban matrix. We addressed this problem using a case study of the squirrel glider ( Petaurus norfolcensis) in fragmented urban landscapes of southeast Queensland, Australia. We applied a mixed effect modeling approach clustered by patch to quantify the importance of site-level habitat factors relative to edge contrast and habitat patch size on squirrel glider abundance. Analysis of variance was used to test for differences in glider age and sex in interior habitats compared to road and residential edges. We found that edge contrast had a strong negative effect on the abundance of squirrel gliders but is conditional on the presence of a low numbers of unreliable flowering overstorey trees and the availability of critical resources such as nest hollows at a site. We also found that older male gliders prefer forest fragment interiors over road and residential edge habitats. We conclude that although interior habitats are ideal to maintain large stable populations, the conservation value of low contrast edges containing key site-level resources should not be underestimated for arboreal mammals such as the squirrel glider.

Nest-box use by arboreal mammals in a peri-urban landscape

Context. Nest boxes provide important nesting, denning and shelter sites for many fauna species worldwide, but we know little about the factors that influence the suitability of nest boxes for particular species. Such information is crucial in urban landscapes where natural hollows are scarce. Aims. The aim of this study was to record the use of nest boxes by sugar gliders (Petaurus breviceps), squirrel gliders (P. norfolcensis) and other fauna in a peri-urban landscape in northern Victoria and examine factors at multiple spatial scales that may influence nest-box use. Methods. We monitored the use of 102 nest boxes over three seasons in 2006. Attributes that may influence nest-box occupancy were measured at five different spatial scales: (i) landscape; (ii) the habitat beyond 20 m of the nest box; (iii) the habitat within 20 m of the nest box; (iv) the tree that the nest box was located in; and (v) the nest box. Key results. At the landscape scale, topography influenced nest-box occupancy with squirrel gliders using boxes in flat or gully areas, and sugar gliders using boxes in gully, mid-slope or ridge areas. For habitat beyond 20 m of the nest box, sugar gliders were more likely to occupy boxes with a higher density of surrounding nest boxes and a higher density of residential dwellings. Within 20 m of the nest box, boxes occupied by sugar gliders were more likely to occur in areas with a higher density of acacia shrubs and lower density of hollow-bearing trees, whereas the presence of acacia did not influence nest-box use by squirrel gliders. At the scale of the nest-box tree, boxes occupied by sugar gliders were more likely to be on smaller trees (based on height and diameter) and on box (e.g. red box Eucalyptus polyanthemos) species. The only nest-box characteristic to have a strong relationship with occupancy was date of establishment, with longer established boxes more likely to be occupied. Conclusions. Our study demonstrates that various factors influence nest-box use at different scales and nest boxes remain an important conservation and management tool in heavily modified landscapes. Implications. Land managers and groups should be aware that nest boxes may help to alleviate some of the negative impacts of the loss of hollow-bearing trees in low density urban areas, but nest-box use will vary depending on landscape context, habitat factors, box design, and the ecological traits of the target species. Each of these factors must be considered to maximise the conservation benefits of nest-box programs.