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Personality traits shape individual perceptions of risks and rewards, and so, should affect how animals value and use their environment. Evidence is emerging that personality affects foraging, space use, and exploitation of novel environments such as urban habitat. But the influence of personality is also hypothesized to be sex-dependent when primary motivation for space use differs between sexes, as often occurs in polygynous species. We tested the influence of personality traits, interacting with sex, on space use by the polygynous common brushtail possum, Trichosurus vulpecula, in an urban-woodland boundary in Sydney, Australia. We quantified personality traits, including exploration, using behavioral assays in an artificial arena. We also GPS-tracked free-ranging individuals, and measured range size, core area: home range, and proportional urban range. We found that personality traits affected space use either as a main effect or, as predicted, an interaction with sex. More exploratory animals, regardless of sex, had higher core area: home range ratios and proportionally larger ranges within urban habitat. However, less exploratory females yet more exploratory males had larger ranges. Our findings provide new insight into movement ecology by demonstrating, for the first time, the sex-dependent influence of personality. The demonstrated influence of personality on urban use by possums also suggests a personality filter for wildlife, as populations transition into urban areas. Finally, as individuals at the interface between urban and natural habitat are also a conduit between the two, a corollary of our findings is that there may be personality-mediated spread of disease across this boundary.

Locating and counting parasites on a host is a fundamental aspect of ecological research and basic veterinary and clinical practice. Variability in the biology and behavior of both hosts and parasites creates many methodological, logistical, and ethical considerations that must be made to collect this deceptively simple measurement. We identified methods that are used to count ticks (Acari: Ixodida, Leach 1815) on hosts by reviewing the methods sections of relevant published studies. Unfortunately, there is no best method agreed upon by scientists to collect ticks from hosts. In general, we suggest that studies focusing purely on counting ticks on hosts should use more sensitive methods to determine patterns of tick distribution on the surfaces of unconscious or deceased hosts in order to provide host body regions to target in future studies to maximize tick detection ability and limit the costs of research for researchers and the host animals involved. As ticks are counted on hosts for many different reasons, researchers must be goal oriented and chose methods that are appropriate for addressing their specific aims.

Males typically adjust their reproductive strategies based on the perceived density and relative abilities of nearby competitors. In high-density populations, repeated encounters facilitate reliable, learned associations between individuals and their relative competitive abilities. In contrast, opportunities to form such associations are limited when densities are low or in flux, increasing the risk that individuals will unintentionally engage in potentially costly interactions with higher-quality or aggressive opponents. To maximize their fitness, individuals in low-density and fluctuating populations therefore need a general way to assess their current social environment, and thus their relative competitive ability. Here, we investigate how olfactory social signals (scent marks) might perform this function. We manipulated the perceived social environment of isolated, male house mice ( Mus domesticus ) via their periodic contact with scent marks from 3 or 9 male conspecifics, or a control of no scents, over 15 days. We then paired them with an unknown opponent and examined how the diversity of recent scent contact mediated their behavior towards dominant or subordinate opponents. There was an overall pattern for increasing scent diversity to significantly reduce male mice’s aggression (tail rattling and lunging) towards their opponents, and also their willingness to engage in reciprocal investigation. Such cautiousness was not indicative of perceived subordinance, however; the diversity of recent scent contact did not affect mice’s investigation of their opponent’s scents, and some measures of aggression were greater when mice faced dominant opponents. These results suggest that house mice can use scent signals to assess their current social environment in the absence of physical interactions, modifying their behavior in ways that are predicted to reduce their risks of injury when the likelihood of encountering unknown opponents increases.

The persistence of wildlife in fragmented landscapes is predicted to rely on the presence of critical habitat elements. In urban landscapes, the persistence of hollow-dependent bats arguably depends upon the protection of roosting habitat, yet knowledge of bat roosting requirements within these landscapes is limited. We used radiotelemetry to locate day roosts of a species considered sensitive to urbanization, Gould's long-eared bat (Nyctophilus gouldi), in suburban bushland in Sydney, New South Wales, Australia. We compared roost selection data collected for 9 individuals during the mating season (March–April 2009) and 10 individuals during the maternity season (November–December 2009). We found 41 roosts of N. gouldi under decorticating bark and in tree hollows, which were all located in 1 suburban bushland reserve (∼40 ha), with roosts rarely located elsewhere, despite the abundance of available trees in smaller patches outside of the reserve. N. gouldi displayed a clear preference for trees w...

Habitat use of quokka (Setonix brachyurus) in the northern jarrah forest of Western Australia was determined by monitoring movements of 58 quokkas over 2 years in 5 local populations. Quokkas were largely restricted to Agonis swamps that occur patchily throughout the jarrah forest. Within swamps, they are habitat specialists, preferring early seral stages that have been burned within the previous 10 years. This preference derives from a combination of dietary requirements and refuge from predation. As swamps mature they become suboptimal, forcing quokkas to colonize new patches. Since the collapse of the metapopulation following the introduction of the European red fox (Vulpes vulpes) in the 1930s, quokkas have been forced to remain at a site because predation inhibits dispersal.

Predator-avoidance behavior of native bush rats ( Rattus fuscipes ) to an introduced predator ( Vulpes vulpes ) was investigated by measuring their responses to predator odor. Trapping success of wild bush rats was compared between clean traps and traps scented with fox odor, set along creeks in Namadgi National Park in southeastern Australia. Two experimental designs were used; the first measured trapping success of clean and scented traps alternating along a trapline through bush rat habitat in winter, spring and summer. The second design offered a choice of clean and scented traps at each trap station and was repeated in spring and summer. Relative trapping successes were analyzed to determine if rats avoided fox odor. Multiple t- tests showed no avoidance responses with similar numbers of captures in clean and fox-scented traps. Consequences of the apparent naivete of bush rats to the odor of an introduced predator are discussed.