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Knowledge of animal responses to fire is fundamental to wildlife management in fire‐prone ecosystems. Fire can influence the occurrence of large herbivores by altering the structure and composition of vegetation. However, how fire affects herbivore occurrence in many ecosystems is poorly understood. Large herbivores may be attracted to burnt areas due to higher foraging quality. Conversely, herbivores may avoid burnt areas due to heightened predation risk. We tested the influence of vegetation type and fire history variables on the occurrence of macropods at Booderee National Park in south‐eastern Australia. We documented macropod occurrence at 107 long‐term monitoring sites using spotlighting surveys conducted between 2003 and 2019. We modelled relationships between the occurrence of the eastern grey kangaroo (Macropus giganteus) and the swamp wallaby (Wallabia bicolor) with three fire history variables; time since fire, fire frequency and burn context (the proportion of the area surrounding each site that was recently burnt), as well as their interaction with vegetation type. We found both macropod species selected recently burnt sites, likely due to a higher abundance of preferred plants at these sites. Increasing fire frequency was associated with a reduced occurrence of the eastern grey kangaroo. The occurrence of both macropod species was significantly higher in forest sites, possibly reflecting higher foraging quality of grass and shrub species compared to woodland, heathland and shrubland sites. We suggest that if fire is used as a management tool, it is important to recognise potential feedbacks from increased foraging pressure from large herbivores. Future fire management will need to avoid burning areas of sensitive vegetation if local herbivores display pyric herbivory responses, and/or avoid small‐scale burns, which may concentrate foraging pressure. [ABSTRACT FROM AUTHOR]

Green leaves of six grass species in temperate Australia showed considerable circadian variation (especially in summer) in water content, which peaked late in the night and fell from sunrise to an afternoon minimum. In summer, water content of a set of ‘wetter’ species ( Axonopus affinis, Pennisetum clandestinum and Paspalum dilatatum) was consistently higher and varied less profoundly through the 24 h than that of a ‘drier’ set ( Imperata cylindrica, Poa labillardieri and Themeda triandra). Hour-to-hour and day-to-day variation in leaf water content of P. dilatatum in summer partly but imperfectly reflected ambient temperature. Recognizing the risks for herbivores of visiting water sources, we considered leaf water content as a source of free water for leaf-grazing herbivores, eastern grey kangaroos Macropus giganteus and common wombats Vombatus ursinus. Using known field metabolic rates, energy requirements and digestive efficiencies, we calculated these two species' free-water intakes when satisfying their energy needs with these grasses but distributing their grazing in different schedules. Both species would obtain more free water by their observed foraging schedules than by random or daytime-only schedules. We calculated that the measured grasses could satisfy the water requirements of wombats but not always those of kangaroos, who would need to drink when forage water content was less than about 70%. Water content of grass leaf could rise above and fall below this value within a day, creating some scope for kangaroos to manage their need to visit water by adjusting foraging schedules or choice of grass species. In future studies, circadian variation in leaf water content should be considered as a factor (together with their thermal physiology) driving herbivores' activity scheduling, and affecting their dietary selection. [ABSTRACT FROM AUTHOR]

Abstract We investigated the impact of red fox (Vulpes vulpes Linnaeus 1758) predation on juvenile eastern grey kangaroos (Macropus giganteus Shaw 1790) using a replicated predator removal experiment. In two sites in Namadgi National Park, south-eastern Australia, a persistent 1080 poisoning campaign over 18 months reduced fox density by more than 85%, and to less than 10% of the fox density in two other sites with no fox baiting. Changes in the mother: young ratios and densities of kangaroo populations were monitored twice monthly along 2-km transects in each site from July 1993 to February 1995. Compared to nonremoval sites, where foxes were controlled, 25–40% more females retained juveniles over the period when these young became emergent from the pouch. This higher survival of emergent pouch young resulted in a significantly higher proportion of juveniles in kangaroo populations at fox control sites, which resulted in a significantly higher annual growth rate. We conclude that predation upon juveniles is an important limiting factor for kangaroo populations in Namadgi NP. [ABSTRACT FROM AUTHOR]