Sustainable Grazing in the Channel Country Floodplains (phase 2) : A technical report on findings between March 2003 and June 2006

‘Sustainable Grazing in the Channel Country Floodplains’ was initiated by industry to redress the lack of objective information for sustainable management in the floodplains of Cooper Creek and the Diamantina and Georgina Rivers. The project has maintained links with the grazing community and has extensively drawn upon expert local experience and knowledge. The project has provided tools for managers to better anticipate the size of beneficial flooding arising from rains in the upper catchment and to more objectively assess the value of the pasture resulting from flooding. The latest information from the project has enabled customisation of the EDGENetwork™ Grazing Land Management training package for the Channel Country. In combination, these tools will assist in making earlier cattle stocking decisions, including when cattle may need to be mustered out of floodplain paddocks, how many additional cattle will be required to take advantage of the flood–grown pasture, and the timing of cattle turnoff. These will reduce costs by providing a greater lead time to plan cattle movements and purchases, and may enhance the sustainability of the resource base by better matching cattle numbers with the feed on offer.

Satellite Telemetry and Long-Range Bat Movements.

Background: Understanding the long-distance movement of bats has direct relevance to studies of population dynamics, ecology, disease emergence, and conservation. Methodology/Principal Findings: We developed and trialed several collar and platform terminal transmitter (PTT) combinations on both free-living and captive fruit bats (Family Pteropodidae: Genus Pteropus). We examined transmitter weight, size, profile and comfort as key determinants of maximized transmitter activity. We then tested the importance of bat-related variables (species size/weight, roosting habitat and behavior) and environmental variables (day-length, rainfall pattern) in determining optimal collar/PTT configuration. We compared battery- and solar-powered PTT performance in various field situations, and found the latter more successful in maintaining voltage on species that roosted higher in the tree canopy, and at lower density, than those that roost more densely and lower in trees. Finally, we trialed transmitter accuracy, and found that actual distance errors and Argos location class error estimates were in broad agreement. Conclusions/Significance: We conclude that no single collar or transmitter design is optimal for all bat species, and that species size/weight, species ecology and study objectives are key design considerations. Our study provides a strategy for collar and platform choice that will be applicable to a larger number of bat species as transmitter size and weight continue to decrease in the future.

The short-term effects of a routine poisoning campaign on the movements and detectability of a social top-predator

Top-predators can be important components of resilient ecosystems, but they are still controlled in many places to mitigate a variety of economic, environmental and/or social impacts. Lethal control is often achieved through the broad-scale application of poisoned baits. Understanding the direct and indirect effects of such lethal control on subsequent movements and behaviour of survivors is an important pre-requisite for interpreting the efficacy and ecological outcomes of top-predator control. In this study, we use GPS tracking collars to investigate the fine-scale and short-term movements of dingoes (Canis lupus dingo and other wild dogs) in response to a routine poison-baiting program as an example of how a common, social top-predator can respond (behaviourally) to moderate levels of population reduction. We found no consistent control-induced differences in home range size or location, daily distance travelled, speed of travel, temporal activity patterns or road/trail usage for the seven surviving dingoes we monitored immediately before and after a typical lethal control event. These data suggest that the spatial behaviour of surviving dingoes was not altered in ways likely to affect their detectability, and if control-induced changes in dingoes' ecological function did occur, these may not be related to altered spatial behaviour or movement patterns.