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As early morning bird vocalisation is a major feature of many bird communities, longitudinal profiles of vocal activity data, collected using sound recorders, were compared for a range of habitat types in the Tumut area of south-eastern Australia. There was a significant, and roughly linear, decline in vocal activity across the morning after an initial early peak of activity. Vocal activity persisted longer at sites located within large areas of continuous eucalypt forest than in the strip- and patch-shaped eucalypt remnants surrounded by extensive stands of radiata pine or at sites dominated by stands of radiata pine. There was evidence that the pattern of persistence of vocal activity differed among the different bird groups.

This paper presents the results of a study of the use of den trees by the greater glider (Petauroides volans) in five patches of remnant eucalypt forest embedded within an extensive radiata pine (Pinus radiata) plantation near Tumut in south-eastern Australia. Radio-tracking was used to identify 171 den trees occupied by 40 animals over 948 animal-tracking days between September 1997 and September 1998. All radio-tracked P. volans used multiple den trees. Males used significantly more den trees than females and a greater proportion of these were used for single visits. Males also used fewer new den trees over the study period in the smaller patches, although they still used more than females. In the larger patches, males and females used similar numbers of den trees.
Commonly used den trees tended to be situated in (or close to) core areas of an individual's home range. Den tree sharing, either concurrently or independently, was predominantly between adult males and females, or between adults and their young. Trees most likely to be used by more than one individual had the same characteristics as trees that had the highest probability of use per se – that is, they were of large 'average size'.

Morning vocal activity data for birds were collected using automatic sound recorders at 165 sites in fragmented forests at Tumut in south-eastern Australia. A model was developed to describe the statistical properties of the vocal activity data and study the relationship between the number of 'elements' (or notes) broadcast by birds and the number of birds recorded by human observers. We discuss the practical issues of finding a model where variance heterogeneity and skewness is a feature of the data, while the context of the problem required that multiplicative relationships be preserved. A satisfactory fit to our vocal activity data was obtained by using a Gamma distribution.For most groups of birds, the observed relationships between vocal activity and the number of birds recorded by human point counts were weak but statistically significant.Our analysis suggests that these data provide limited useful information about vocal activity per bird. Automatic sound-recording data may be informative for drawing inferences about temporal patterns in vocal activity but do not seem useful as a method for estimating the abundance of birds. A significant relationship was identified between the number of species vocalising, as measured by sound recorders, and the number of species observed by point count method. However, the relationship was far from isometric and there were many more species detected by the sound recorders than by human observers.Results from analyses of vocal activity data gathered at Tumut were confirmed by additional data obtained in a subsequent, small calibration study in the Namadgi National Park in the Australian Capital Territory.

Night-time use of feed trees by 40 radio-collared individuals of the greater glider (Petauroides volans) was recorded within five remnant patches of eucalypt forest near Tumut in south-eastern Australia. Radio-collared animals were observed making 663 night-time visits to 433 trees. For these observations, we recorded the number of visits by an animal to each tree, the number of different animals using each tree, the characteristics of trees that animals used, and the category of activity or behaviour displayed by animals (classified as feeding, perching, and moving).
We found no evidence of a significant difference in patterns of behaviour between male and female P. volans in their night-time use of trees within remnant patches, regardless of patch size or population density. There were few records of animals (4%) from the radiata pine (Pinus radiata) plantation that surrounded the eucalypt remnants, although 20 observations were made of P. volans feeding on the young male cones and buds of this introduced tree species. There was evidence of preference for feeding in ribbon gum (Eucalyptus viminalis), mountain gum (E. dalrympleana) and narrow-leaved peppermint (E. radiata), with 72% of feeding observations of P. volans coming from these three tree species. Animals were generally solitary and spent most of the night feeding and perching in the upper canopy. Most trees were used by a single individual, with 96% of observations being of a single animal in a tree. The limited number of cases of sharing and co-use of trees were generally between an adult male and adult female (assumed mates), and females and their young. The probability that a tree was used increased with the average size of a tree (a composite measure of diameter, height and crown features) until approaching an asymptote of 1.0, i.e. all large trees were used. The number of visits a tree received from P. volans also was positively related to the measure of its size.

This paper examines home-range attributes of 40 greater gliders (Petauroides volans) in five patches of remnant eucalypt forest surrounded by stands of radiata pine (Pinus radiata) near Tumut in south-eastern Australia. Fixed-kernel smoothing methods were used to estimate home-range size for P. volans. For males, home-range size varied from 1.38–4.10 ha (mean = 2.6 ± 0.8 ha, n = 12) and was significantly larger (P < 0.05) than for females (1.26–2.97 ha, mean = 2.0 ± 0.6 ha, n = 11). Home-range size increased significantly with increasing patch size and reduced patch population density. Thus, small patches had more animals per unit area with smaller home ranges and greater home-range overlap.
Our findings illustrate flexibility in the use of space by P. volans. Such results have not previously been reported for P. volans or any other species of arboreal marsupial. Considerable home-range overlap (at 95th percentile isopleth level) was observed between male and female P. volans. Pairs of females also exhibited home-range overlap. Males tended to maintain home ranges exclusive of other males, although some shared common areas. Contrary to the large variations observed in home-range area, core areas (50th isopleth) remained relatively constant, regardless of patch size, population density or sex. This may indicate that core areas are an essential requirement for individuals and resources they contain cannot be shared with congeners.

We report on the effects of broad-scale restoration treatments on the ground layer of eucalypt grassy woodland in south-eastern Australia. The experiment was conducted in two conservation reserves from which livestock grazing had previously been removed. Changes in biomass, species diversity, ground-cover attributes and life-form were analysed over a 4-year period in relation to the following experimental interventions: (1) reduced kangaroo density, (2) addition of coarse woody debris and (3) fire (a single burn). Reducing kangaroo density doubled total biomass in one reserve, but no effects on exotic biomass, species counts or ground cover attributes were observed. Coarse woody debris also promoted biomass, particularly exotic annual forbs, as well as plant diversity in one of the reserves. The single burn reduced biomass, but changed little else. Overall, we found the main driver of change to be the favourable growth seasons that had followed a period of drought. This resulted in biomass increasing by 67%, (mostly owing to the growth of perennial native grasses), whereas overall native species counts increased by 18%, and exotic species declined by 20% over the 4-year observation period. Strategic management of grazing pressure, use of fire where biomass has accumulated and placement of coarse woody debris in areas of persistent erosion will contribute to improvements in soil and vegetation condition, and gains in biodiversity, in the future. ; Funding and in-kind logistic support for this project was provided by the ACT Government as part of an Australian Research Council Linkage Grant (LP0561817; LP110100126). Drafts of the manuscript were read by Saul Cunningham and Ben Macdonald.

We report on the effects of broad-scale restoration treatments on the ground layer of eucalypt grassy woodland in south-eastern Australia. The experiment was conducted in two conservation reserves from which livestock grazing had previously been removed. Changes in biomass, species diversity, ground-cover attributes and life-form were analysed over a 4-year period in relation to the following experimental interventions: (1) reduced kangaroo density, (2) addition of coarse woody debris and (3) fire (a single burn). Reducing kangaroo density doubled total biomass in one reserve, but no effects on exotic biomass, species counts or ground cover attributes were observed. Coarse woody debris also promoted biomass, particularly exotic annual forbs, as well as plant diversity in one of the reserves. The single burn reduced biomass, but changed little else. Overall, we found the main driver of change to be the favourable growth seasons that had followed a period of drought. This resulted in biomass increasing by 67%, (mostly owing to the growth of perennial native grasses), whereas overall native species counts increased by 18%, and exotic species declined by 20% over the 4-year observation period. Strategic management of grazing pressure, use of fire where biomass has accumulated and placement of coarse woody debris in areas of persistent erosion will contribute to improvements in soil and vegetation condition, and gains in biodiversity, in the future. ; Funding and in-kind logistic support for this project was provided by the ACT Government as part of an Australian Research Council Linkage Grant (LP0561817; LP110100126). Drafts of the manuscript were read by Saul Cunningham and Ben Macdonald.

In this study, we use data drawn from a series of trapping events on four 0.5-ha trapping grids surveyed in the wet eucalypt forests of central Victoria, south-eastern Australia, to identify relationships between capture probabilities and several factors of interest for three species of small mammals that are common throughout the forests of this region: the agile antechinus (Antechinus agilis), the dusky antechinus (Antechinus swainsonii) and the bush rat (Rattus fuscipes). The design of our study – four regular trapping grids – generated spatio-temporal data with binary responses and many covariates. We used powerful and relatively new statistical methodology to deal with the spatio-temporal dependence patterns in the data – analytical problems that are common in trapping data such as these modelled here. Although A. agilis, A. swainsonii and R. fuscipes are among the best studied mammals in Australia, our data analysis produced new perspectives on their probability of being captured. In particular, we quantified how capture probability is affected by trap position within a trapping grid, day of capture in a sequence of trapping days, history of trap occupancy over time by different species and sexes of those species, time of the year or season, and microhabitat attributes. Our insights are discussed in terms of their consequences for trapping protocols that might be applied in the field.

Two methods of assessing body condition were examined for the mountain
brushtail possum, Trichosurus caninus (Ogilby) at a
single study site in central Victoria, south-eastern Australia. Condition
indices were derived from measures of skeletal size and body mass, and body
water composition was determined using isotopic dilution of tritiated water to
give an estimate of total body water space. There were significant negative
relationships between body water composition and the condition indices for
body length, total length and pes length. Body water composition of
T. caninus was significantly higher in spring than in
winter, and those animals with higher body water composition had lower
absolute neutrophil counts and higher urea values. The relative usefulness of
the two methods used for estimating body condition in
T. caninus is discussed.

Being able to recognise critical habitat features such as nesting and denning sites is essential for wildlife conservation. It is particularly true for the den trees of species threatened by habitat loss, such as the squirrel glider (Petaurus norfolcensis). Measurements of 146 den trees of the squirrel glider were made in fragmented woodlands of the South-west Slopes of New South Wales and data compared with random trees to quantify the key characteristics of den sites. The likelihood of use as a den tree increased with increasing numbers of visible tree hollows and tree size. Dieback was also a positive indicator of den use. However, when visible hollows within a tree are abundant, dieback-free trees were preferred. Measures of den tree context such as basal area, the number of neighbouring large trees and distance to the next nearest tree, were also found to be important determinants of the likelihood of usage. The above variables were combined into a multiple regression model. The squirrel glider favoured particular Eucalyptus species and some broader eucalypt groups. We believe such variations were most likely due to interspecific differences in hollow development and dieback among the various groups, rather than bark type, a factor previously cited as an important determinant of den tree usage. The 'best' model had high negative predictive power, suggesting it would be useful for identifying (1) trees that could be felled without a loss of this critical habitat resource (e.g. at development sites) and (2) areas unsuitable for potential squirrel glider relocation or habitat enhancement. Squirrel gliders show preference for a combination of tree and tree context features in selecting den trees. Understanding these features will help managers enhance and protect denning resources for this species.

The results are reported of a nest-box study conducted in two locations in the mountain ash (Eucalyptus regnans) forests of the Central Highlands of Victoria (south-eastern Australia) to compare usage of different nest-box designs located at different heights in trees. A total of 96 nest boxes was established using a rigorous experimental design – two regions (Powelltown and Toolangi State Forests), two forest age classes (20-year post-logging regrowth and 60-year fire- and salvage-logging regrowth), two nest-box designs (large boxes with large entrance holes and small boxes with small entrance holes), and two heights at which nest boxes were attached to trees (3 m and 8 m above the ground). The study entailed setting out four nest boxes at each of 24 sites to meet the design criteria. Evidence of occupancy by vertebrates was recorded in a total of 19 of 96 boxes on 11 of 24 sites site during regular inspections over more than three years. Thirteen boxes were used by Leadbeater's possum (Gymnobelideus leadbeateri), six by the mountain brushtail possum (Trichosurus cunninghami) and seven by the common ringtail possum (Pseudocheirus peregrinus). The common ringtail possum and mountain brushtail possum were seen only in high–large boxes but Leadbeater's possum used all but the low–large boxes. There was evidence of spatial dependence in usage patterns, with all four boxes at a given site showing signs of eventually being occupied. Only two nest boxes located in mountain ash forest regenerating after the 1939 wildfires were occupied. Relatively limited use of nest boxes supports concerns about the use of a nest box over large scales and long timeframes as an effective recovery tool for species threatened by the loss and subsequent shortage in the numbers of naturally occurring hollows.

The efficacy of spotlighting as a field survey technique for detecting the
greater glider (Petauroides volans) was assessed by
comparing the precise location of radio-tracked animals with locations
determined simultaneously from spotlighting searches. Radio-collars were
fitted to 20 greater gliders in three eucalypt patches embedded within an
extensive radiata pine (Pinus radiata) plantation near
Tumut in south-eastern New South Wales. Our success rate for detecting
collared animals was low, even when survey effort was increased. These
findings suggest that spotlighting underestimates actual population size. A
further, properly designed study, in different forest types is needed to
provide precise estimates of the magnitude of the bias in counts of
P. volans obtained by spotlighting.

We compare detection rates of different species of mammals by three types of
hairtubes in both the mountain ash forests of the central highlands of
Victoria and a range of wet forest types at Tumut in southern New South Wales.
The types of hairtubes were a small-diameter PVC pipe, a large-diameter PVC
pipe and a newly constructed tapered hair funnel. Data were analysed for brown
antechinus (Antechinus stuartii), bush rat
(Rattus fuscipes), common wombat
(Vombatus ursinus), swamp wallaby
(Wallabia bicolor) and common and mountain brushtail
possums (Trichosurus vulpecula and
T. caninus). The most effective hairtube type (i.e. the
one yielding the highest number of detections) varied between species: small
hairtubes forR. fuscipes, hair funnels for
Trichosurus spp., and large hairtubes for
V. ursinus and W. bicolor. For
A. stuartii, the most effective hairtube type differed
between the two study regions (hair funnels in Victoria and small hairtubes at
Tumut). Detection by more than one hairtube type at a given plot was uncommon.
Our findings have important implications for field surveys and how data
gathered from such studies are interpreted. For example, if the aim of field
survey is to detect a wide range of species then several types of hairtubes
may need to be deployed.