Habitat loss and fragmentation threaten koala persistence in south-east Queensland, intensifying the challenges posed by climate change and disease to koala survival. Adaptation to modified landscapes may mediate species’ persistence, so we collected location and accelerometery data for 10 koalas in a changing landscape in the Moreton Bay region of Queensland, using remote global positioning system (GPS) collars and manual tracking. We investigated whether ambient temperature influenced how active koalas were and how far they moved, and compared area of use estimated by manual tracking and remote GPS uploads. Accelerometric data showed that koalas were more active at night, and GPS data showed that males moved further than females, but accelerometers measuring activity were not indicative of total distance travelled. Distance moved by koalas per day and night was greatest from May through August and least during March for both males and females. Remotely uploaded GPS locations described a not significantly larger total area of use by each koala compared to manual VHF tracking. There was no general trend in the relationship between day temperature and koala activity or distance moved.

The koala (Phascolarctos cinereus) is recognised as threatened across two thirds of its distribution and identified as particularly susceptible to climate change. The aim of this study was to assess the spatio-temporal variation in microclimate across koala home ranges and determine any tendency for koalas to exploit this variability. Temperature data loggers were set out in a grid pattern across the study site on St Bees Island, Queensland. Resident koalas were collared with GPS units recording location at night or during the day. Our results revealed that temperature variation across the landscape was greatest on the hottest days (~10 °C). During the day, koalas were found in areas of the landscape that recorded lower daytime temperatures, and during the night, they were found in areas that recorded the highest daytime temperatures. We postulate that koalas avoided the hottest areas of their range during summer days and were more likely to use cooler non-fodder trees but utilised them at night because these areas corresponded with the location of fodder trees. From our results, we suggest that the microclimate of non-fodder trees both (a) explains their selection by koalas during the day and (b) highlights their importance to koala persistence, in addition to the known fodder species.

Koalas are an iconic Australian species now classified as nationally endangered due to habitat loss, predation, disease, and vehicle collisions. Yet, because of their nocturnal and arboreal nature, koala movement on the ground between trees remains poorly described. Ground visits are fraught with danger, with two-thirds of koala deaths occurring due to vehicle strikes and dog attacks. Quantifying these behaviours can provide insights for conservation efforts targeted to their time on the ground. To quantify detailed movement patterns, we collared nine koalas in a highly fragmented agricultural landscape with tri-axial accelerometers for 8.50 ± 1.17 days. Using an annotated dataset of observed behaviours, we trained Random Forest models to classify four main behavioural states: Motionless in Tree, Feeding & Grooming in Tree, Other Movement in Tree, and Walking. Koalas spent 57.5% ± 14.2% of their time moving in trees, 26.8% ± 13.5% motionless in trees, 15.6% ± 2.7% feeding and grooming, and only 0.2% ± 0.1% walking on the ground (around 3 min daily). Koalas walked most frequently between 2 am and 5 am. Our findings highlight a major discrepancy between mortality rates on the ground and frequency of ground time, indicating that focused mitigation during these infrequent events could yield disproportionately high conservation benefits.

We evaluated long range antennae and associated solar-powered global positioning system (GPS) ear tags designed for use with domestic cattle, as a novel system for monitoring ranging behaviour of the koala (Phascolarctos cinereus). The mean location error of our GPS tags was 33.9 m (s.e. = 0.46). The tags were relatively light (30 g), reported eight locations per day when attached to koala radio-collars and had an operating life that exceeded our study period (8 months). Deployed as a stand-alone, solar powered, remote system, this technology can provide a viable option for wildlife tracking projects.

The distribution of the koala (Phascolarctos cinereus) in Queensland is predicted to contract as a result of climate change, driven by the frequency, intensity and duration of heatwaves and drought. However, little is known about the physiological responses of this species to environmental extremes under field conditions. This study aimed to establish the efficacy of surgically implanted thermal radio transmitters and data loggers to measure the body temperature of free-ranging koalas across a range of environmental conditions and ambient temperatures. Five free-ranging koalas in southeast Queensland were implanted with thermal transmitters and data loggers waxed together as a single package. Body temperatures were recorded for variable periods ranging from 3 to 12 months. Diurnal rhythms in body temperature were detected irrespective of season. The long-term diurnal body temperature peak for all koalas occurred between 16:00 and 17:00 h and body temperature was 36.7–36.9 °C, the long-term nadir occurred between 07:00 and 08:00 h and body temperature was 35.4–35.7 °C. Koala body temperatures as low as 34.2 °C and as high as 39.0 °C were recorded. Thermolability became apparent when ambient temperatures were outside the deduced thermal neutral zone for koalas (14.5–24.5 °C): heat was accumulated during the day and dissipated during the cool of the night. While this study is the first to report on body temperature of free-ranging koalas in their normal behavioural context, further investigations are necessary to determine the physiological boundaries of the thermal niche for this species, in order to better equip models that will more accurately predict the impacts of climate change on koalas.

Habitat loss and fragmentation threaten the survival of koalas in Queensland. In rural landscapes, remaining koala habitat is often in the form of scattered paddock trees, patches of vegetation and roadside vegetation. The aims of this study were to (1) quantify the use of these three habitat types; (2) determine whether there is an increased use of scattered trees during the breeding season; and (3) describe the movement characteristics (daily step-length and turning angle) of koalas in different habitat types. To do this, koalas were caught and fitted with global positioning system (GPS) loggers that recorded their daily locations. We found koalas utilised all three habitat types in both breeding and non-breeding seasons, but roadside vegetation and scattered trees were utilised significantly more than expected based on their availability within the landscape. We found no significant difference in step-length or turning angles in scattered trees compared with patches of vegetation. We conclude that scattered trees are a critical element of habitat in this rural landscape. This work provides evidence that retaining or planting scattered trees within the rural landscape would likely complement or possibly enhance the conservation value of rural landscapes for koalas.

Daylight saving time (DST) could reduce collisions with wildlife by changing the timing of commuter traffic relative to the behaviour of nocturnal animals. To test this idea, we tracked wild koalas ( Phascolarctos cinereus ) in southeast Queensland, where koalas have declined by 80% in the last 20 years, and compared their movements with traffic patterns along roads where they are often killed. Using a simple model, we found that DST could decrease collisions with koalas by 8% on weekdays and 11% at weekends, simply by shifting the timing of traffic relative to darkness. Wildlife conservation and road safety should become part of the debate on DST.

The rapid expansion of urban landscapes has significant consequences for wildlife. Habitat loss and fragmentation cause significant loss of species richness. While remnant fragments of habitat are important areas for conservation, the urban matrix between fragments is also critical. Increasing the suitability of the matrix for wildlife can increase the diversity of wildlife that utilise urban landscapes and increases the potential for dispersal among fragments. We investigated the effectiveness of retaining remnant trees during for increasing the species richness and abundance of birds in new urban housing developments. We measured species richness and abundance in four habitat types: non-vegetated streets, vegetated streets, recreational parks and bush sites. We discovered that the number of bird species observed was lowest on the non-vegetated streets and highest within the bush fragments. Species richness on vegetated streets was intermediate between non-vegetated streets and parks. The abundance of birds was highest within recreational parks and we observed significantly more birds on vegetated streets than non-vegetated streets. Additionally, we found the number of species and total abundance of birds was positively associated with the total number of retained mature trees within a vegetated street. The dominant feeding guild and species composition varied between the different habitat types. Our findings suggest that increasing the number of retained mature trees in new housing developments may be an effective means of increasing the number of bird species that utilise the urban matrix. (C) 2014 Elsevier B.V. All rights reserved.

The low pH of naturally acidic aquatic environments is the result of soft-water with low buffering capacity and high concentrations of natural organic acids. Our current understanding of the influence of pH on aquatic organisms is largely limited to laboratory studies conducted under controlled conditions with little incorporation of these organic acids. Recent studies suggest natural organic acids may influence the physiology of aquatic species independent of low pH. We examined the effects of pH and varying concentrations of natural wallum water, which is high in organic acids on the hatching success, growth and locomotor performance of larval striped marsh frogs (Limnodynastes peronii). Based on previous studies, we predicted that the detrimental effects of low pH would be further exacerbated by higher concentrations of naturally occurring organic acids (high concentrations of wallum water). In artificial soft-water, embryos experienced both reduced growth and reduced survival when exposed to low pH. However, greater concentrations of natural organic acids did not exacerbate these effects of low pH on growth and development. Instead, we found some evidence that the natural organic acids within wallum water improved growth and swimming performance across all pH treatments. Using path analyses to investigate the effects of pH and natural organic acid concentration on burst swimming performance, we found performance was directly affected by both body length and organic acid concentration. Our data further highlight our limited understanding of the importance of natural organic acids for aquatic organisms and the need to incorporate greater ecological relevance into these studies.