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Roads can have significant impacts on wildlife populations by impeding movement, restricting access to resources and causing wildlife–vehicle collisions. In particular, wildlife–vehicle collisions represent a substantial conservation and social problem, and although mitigation measures are available, an increased understanding of the temporal and spatial patterns of animal movement around roads will enhance their effectiveness. We analysed GPS telemetry data from 47 swamp wallabies Wallabia bicoloron Phillip Island, south-east Australia, within patches of native vegetation dissected by roads. Our aims were to determine if (a) road crossing frequency was influenced by time period (day, night) or sex, (b) wallabies avoided roads, and if avoidance was influenced by time period or sex and (c) road crossing locations were associated with dense vegetation, and other habitat characteristics. We found that males crossed roads more often at night than during the day while females showed the opposite pattern. Further, wallabies avoided roads, with some evidence that avoidance increased at night (p = 0.07). The chance of a wallaby crossing roads with high speed limits (80–100 km h-1) increased with vegetation density during the day but not at night. In contrast, vegetation density had no influence on crossing locations along roads with lower (50–70 km h-1) speed limits during the day or night. Both vegetation density and vehicle speed may influence wallaby–vehicle collisions and suggest management strategies targeting these factors. Partial fencing guiding wallabies towards safer crossing locations, combined with other measures such as reduced speed limits and signage, could reduce collisions between vehicles and swamp wallabies on Phillip Island.

Reference intervals (RIs) describe baseline parameters of healthy animals, providing a powerful tool for wildlife managers to monitor health, identify disease and assess animal welfare. This paper reports haematological, glucose and serum protein RIs for one of Australia's most iconic and managed mammals, the eastern grey kangaroo Macropus giganteus. Blood samples (n = 514) were collected from 11 populations of eastern grey kangaroos, across much of their geographic range. A species-level RI was initially established based on samples collected from four sites (n = 245) and was further partitioned based on significant differences associated with sexual maturity and season. Unique population means were established from a further seven sites to investigate the importance of biotic (sex and sexual maturity) and abiotic (season, site, rainfall, temperature and laboratory) factors on kangaroo health parameters. Random forest analysis of health parameters revealed that abiotic factors (site, rainfall, temperature and season) were largely responsible for differences in haematological, glucose and serum protein values. Sex was found to have no influence, while sexual maturity and laboratory of analysis had moderate effects. Based on these findings, interpretation of individual and population haematological and serum protein values requires careful consideration of the timing of sample collection, environmental conditions and sexual maturity. When assessing kangaroo health, the relevant sexual maturity RI must be considered initially. For populations with similarities to those described (for example high density or captive populations) users should also consider site specific mean haematological and serum protein values. The RIs reported are valuable when establishing the health status of kangaroo populations. Furthermore, understanding the influence of biotic and abiotic factors will improve the utility of these RIs to assess health, disease status and improve welfare in eastern grey kangaroos.

The Jarman–Bell principle seeks to explain why smaller herbivore species tend to select higher-quality forage (high protein and high fiber digestibility) than larger herbivore species. This principle may also provide insight into intraspecific differences in resource use in species with pronounced sexual size dimorphism. We examined the relationship between body mass and diet quality in a sexually dimorphic macropodid community comprising larger (17–55 kg) eastern and western gray kangaroos, Macropus giganteusand M. fuliginosus, and smaller (7–23 kg) red-necked and swamp wallabies, M. rufogriseusand Wallabia bicolor. We determined diet composition through microhistological analysis of fecal pellets, and then assessed diet quality by measuring available nitrogen and fiber (cellulose and hemicellulose) in the plants consumed. We predicted that the smaller species and smaller individuals within species would consume the highest-quality diets. The concentration of fiber consumed differed significantly among species; available nitrogen concentration did not. As predicted, the lowest-fiber diet was consumed by a wallaby (small species) and the highest-fiber diet was consumed by a kangaroo (large species). Contrary to predictions, we detected no sex-based differences in diet quality. However, large male red-necked wallabies consumed diets containing harder-to-digest fiber than small male red-necked wallabies. Body mass and diet type were related between and within species. However, body mass did not account for all differences in diet quality between species; swamp wallabies consumed less fiber than similarly sized red-necked wallabies. These differences are likely related to other adaptations that allow swamp wallabies to better tolerate tannin-rich browse-dominated diets.

Introduced sambar (Rusa unicolor) occur at high density within the Upper Yarra Catchment, an important watershed for the supply of water to Melbourne, Victoria, Australia. Contamination by zoonotic pathogens in sambar fecal pellets poses a serious risk to water quality. We describe spatial and temporal patterns in distribution and density of sambar in the Upper Yarra Catchment between 2003 and 2012, and assess ground‐based culling as a technique to reduce the risk of fecal contamination of the water supply. Sambar density, as indexed by fecal pellet deposition, was inversely related to distance from the reservoir, and aggregations of up to 70 sambar occurred on open flats adjacent to the reservoir, where they foraged mostly at dusk. Culling by ground‐shooting halved fecal pellet density on these flats, primarily through short‐term deterrence rather than a significant reduction of the population. As culling continued, fecal pellet deposition declined further, reducing the likely risk to water supplies. We conclude that localized deterrence through targeted culling of sambar at this site is an effective management technique for decreasing deer fecal deposition and the risk of contamination by zoonotic pathogens of Melbourne's water supply. © 2015 The Wildlife Society.

The success of species reintroduction programmes depends on many factors, including habitat quality and predator occurrence at release locations. For the critically endangered eastern barred bandicoot Perameles gunniiin Australia, successful releases have been achieved only in the absence of predation by the introduced red fox Vulpes vulpes. However, few fox-free sites exist, but those that are fox free may have low habitat suitability, potentially leading to reintroduction failure. We studied a reintroduced population of eastern barred bandicoots at Mt Rothwell, a 420-ha fox-free reserve which appeared to have a degraded foraging range and a lack of nesting material due to overgrazing by marsupial herbivores. We quantified habitat use and measured several variables representing movement distances and nest use. Bandicoots foraged in open grassy areas and nested at sites containing high values of litter, lateral cover and concealment cover. Mean (± SE) home ranges (37.2 ha ± 11.8), daily movement distances (494.6 m ± 32.5) and distances between consecutive nests (122.6 m ± 29.0) were large for males. On average, the length of stay at each nest (2.8 days ± 0.4) was longer than previously recorded values for males, and 13.2% of the nests were used by at least two individuals, suggesting that nesting opportunities were limited. Despite behaviour indicating a low resource base, bandicoots appeared to be surviving and reproducing in our study area, indicating a capacity to live in structurally simple habitat in the absence of predators. Our results are consistent with predator exclusion being a critical factor for successful bandicoot reintroduction.

Monitoring the abundances of prey is important for informing the management of threatened and endangered predators. We evaluated the usefulness of faecal counts and distance sampling for monitoring the abundances of rusa deer Rusa timorensis, feral pig Sus scrofaand water buffalo Bubalus bubalis, the three key prey of the Komodo dragon Varanus komodoensis, at 11 sites on five islands in and around Komodo National Park, eastern Indonesia. We used species-specific global detection functions and cluster sizes (i.e. multiple covariates distance sampling) to estimate densities of rusa deer and feral pig, but there were too few observations to estimate densities of water buffalo. Rusa deer densities varied from from 2.5 to 165.5 deer/km2with coefficients of variation (CVs) of 15-105%. Feral pig densities varied from 0.0 to 25.2 pigs/km2with CVs of 25-106%. There was a positive relationship between estimated faecal densities and estimated population densities for both rusa deer and feral pig: the form of the relationship was non-linear for rusa deer, but there was similar support for linear and non-linear relationships for feral pig. We found that faecal counts were more useful when ungulate densities were too low to estimate densities with distance sampling. Faecal count methods were also easier for field staff to conduct than distance sampling. Because spatial and temporal variation in ungulate density is likely to influence the population dynamics of the Komodo dragon, we recommend that annual monitoring of ungulates in and around Komodo National Park be undertaken using distance sampling and faecal counts. The relationships reported here will also be useful for managers establishing monitoring programmes for feral pig, rusa deer and water buffalo elsewhere in their native and exotic ranges.

Shiny Nematolepis Nematolepis wilsonii is a small understorey tree endemic to Victoria, south east Australia. The species is listed as threatened due to its limited distribution and low abundance. The sole known population, of approximately 400 metres individuals, is located in the Yarra Ranges National Park, Victoria. Paired exclusion plots were erected to investigate the impact of antler rubbing and thrashing activities of Sambar Cervus unicolor on Shiny Nematolepis. Sambar rubbing activities removed, on average, over half the circumference of bark down to the cambium of mature trees. Rubbing damage covered a range of tree sizes, with rubbed individuals in significantly poorer health and exhibiting 19% less relative foliage cover than non-rubbed individuals. Saplings selected by Sambar for thrashing had a significantly greater stem diameter and were most commonly situated beside the road. Other forms of damage to Shiny Nematolepis included storm events and biting by Yellow-tailed Black Cockatoo Calyptorhynchus funereus, but Sambar pose an added threat, which is likely to result in further decline of this threatened population.

Once widespread throughout Victoria, the Eastern Barred Bandicoot Perameles gunnii has declined to near extinction on the Australian mainland due to habitat loss and predation by exotic predators. The last remaining wild population occurs in Hamilton, western Victoria. Founders for a captive breeding program were taken from this population in 1988, which has persisted without predator control or supplementation from captive-bred animals. The species was reintroduced to eight sites from 1989: Woodlands Historic Park, Hamilton Community Parklands, Mooramong, Floating Islands Nature Reserve, Lake Goldsmith, Lanark, Cobra Killuc, and Mount Rothwell. Although all reintroduced populations initially increased, declines were observed during the mid- to late 1990s, from which they have never recovered. A combination of drought and predation by Red Foxes Vulpes vulpes and Cats Felis catus is thought to be responsible. Currently, management techniques focus on intensive control of Red Foxes by poison baiting and shooting, and by construction and maintenance of predator barrier-fences at some sites. Understanding which characteristics lead to the success or failure of a reintroduction site is paramount to the success of the recovery programme for this species. This paper reviews the status of all reintroduction sites, and examines characteristics that could account for the performance of their populations.

Models of kangaroo populations have primarily focused on the prediction of population growth and distribution in relation to environmental variation at broad geographic scales. Current understanding of small-scale patterns in distribution, habitat breadth, and niche occupation is less complete. A powerful model of dispersion is ideal free distribution (IFD) theory. In plant-herbivore grazing systems, the most appropriate IFD models are those that allow for the incorporation of a standing crop of resources. Using eastern grey kangaroos (Macropus giganteus), we test the predictions of a previously described standing-crop IFD model where the number of consumers on a patch is proportional to the resource input rate, the standing crop of resources on all patches at equilibrium are equal (in the absence of interference), and the resource mortality rate is directly equivalent to the resource input rate, and is independent of the resource density (in the absence of interference). We make these comparisons at both the habitat and patch scale. At the habitat scale, we observed significant departures from these predictions that are consistent with the commonly reported occurrence of undermatching, whereas at the patch scale, little concordance with the predictions was observed. These results suggest that eastern grey kangaroos select for resources at the habitat scale but not at the level of the patch.

Benefits of grouping by conspecifics as an anti-predator strategy also should apply in heterospecific associations if species are similar in their vulnerability to predation. I investigated monospecific and heterospecific grouping by sibling species, eastern (Macropus giganteus) and western grey kangaroos (M. fuliginosus), together with smaller and less social red-necked wallabies (M. rufogriseus). I observed groups feeding in mornings and evenings on a grassy airfield in the Grampians National Park, western Victoria, Australia. Wallabies formed smaller monospecific groups than the kangaroos, maintained a greater nearest-neighbor distance, and moved more while feeding. Monospecific groups of the two kangaroo species were indistinguishable in size, composition, spacing, and feeding rates. The percentage of individual grey kangaroos feeding increased with group size in monospecific groups of up to six. Heterospecific groups of kangaroos formed frequently, and the percentage of individual eastern and western greys feeding was not affected by species composition of groups, suggesting that conspecifics and heterospecifics were equally valuable as feeding partners. By contrast, there were few associations between kangaroos and wallabies.

The kelp gull, Larus dominicanus, which is widely distributed around the southern hemisphere, has become established in Australia only in the past half-century. The greatest numbers of kelp gulls in Australia are now found in south-eastern Tasmania in sympatry with the two endemic species, the morphologically similar Pacific gull, L. pacificus, and the smaller silver gull, L. novaehollandiae. We examined populations of the three species in this area. We surveyed large refuse tips and specific shoreline sites in the Hobart area regularly during the winter months in 1981 and again in 1992, recording numbers of each species, and age classes of kelp and Pacific gulls. Between the two survey periods, the number of Pacific gulls and the total number of all gulls present at refuse tips remained unchanged. There was, however, a marked increase in the number of kelp gulls at tips, equivalent to an annual rate of increase of 22.8%, and a corresponding decrease in the number of silver gulls. Kelp gulls of all ages were over-represented at refuse tips, while adult Pacific gulls fed preferentially at more natural shoreline sites. At shoreline sites, adult Pacific gulls appeared to exclude kelp gulls from small bays in 1981, but kelp gulls were present in most of these bays eleven years later. Reducing access to food at refuse tips may be an effective means of controlling the kelp gull population in this area.