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Context: Understanding the diet of invasive species can inform the potential for their distribution into novel habitats. Fallow deer are well established in the grassy woodlands of central Tasmania, Australia, in environments generally considered to be their optimum habitat. They are also increasing their range. The potential range of fallow deer in Tasmania will depend on their ability to vary their diet to exploit new habitats. Diet flexibility will also determine the ecological impacts that fallow deer might have in novel habitats. Aims: We compared the diets of fallow deer in a lowland grassy woodland, where deer have been established for over 150 years, with diets of deer in highland woodlands and forest with less grass cover and higher rainfall, where deer have been established for a shorter time (<50 years). We expected that fallow deer in grassy woodlands would mainly eat grass and forbs, and we wanted to know to what extent the diet of deer differed between habitats. Methods: A metagenomic analysis was performed on fallow deer faecal pellets collected at one lowland and three highland study areas. The method was chosen to maximise information on taxonomic composition of diet and identify plant species that might be affected by deer herbivory to the lowest possible taxonomic level. Key results: Fallow deer ate a wide variety of plant taxa. Diets varied among study areas. In the lowland study area, deer predominantly ate forbs and grasses. In the highland study area deer were more likely to browse on eucalypts and a variety of shrubs. Conclusions: Fallow deer in Tasmania have a broad dietary niche. Availability of specific plant taxa is unlikely to limit fallow deer expansion into most new habitats. Implications: Without stronger management strategies, deer are likely to further increase their range in Tasmania, including into areas with high conservation values. The potential impacts on these areas may be high. Fallow deer in Tasmania exhibit remarkable dietary adaptability, a critical factor in their expanding range. This study compared their diets in established grassy woodlands and newer highland habitats, revealing a broad dietary niche. These findings underscore the urgency of robust management strategies to curb further range expansion and mitigate potential impacts on areas with high conservation values. Photograph by Thomas Guy. [ABSTRACT FROM AUTHOR]

Foraging by African savanna elephant (Loxodonta africana) and other herbivores tends to result in a piosphere effect around water sources, with increasing pressure on vegetation as distance to water decreases. This study aimed to investigate the impacts of pumped waterholes on woody vegetation in the southern portion of Zimbabwe’s Zambezi National Park, a Baikiaea woodland ecosystem characterised by high elephant densities. The recent rehabilitation and addition of pumped waterholes has resulted in a dense waterhole network in the park, prompting concerns around potential negative impacts on vegetation. Sampling plots were located at different distances from four pumped waterholes in Baikiaea plurijuga and Terminalia sericea woodlands. Elephant browsing levels and vegetation structure were assessed across three plant height classes (0.2 -

Abstract Palatable shrubs and trees in rangelands are vulnerable to grazing impacts, with local extinctions and declines documented. However, population trends are difficult to detect due to longevity of individuals and poor understanding of regeneration. We investigated the demography and conservation status of the Grey Range fuchsia (Eremophila stenophylla Chinnock), a geographically restricted and palatable shrub endemic to south-west Queensland. We documented 28 populations over 30,400 km2, with an estimated total population size of 17,000 individuals. Seedling recruitment is rare and seedlings were observed at six populations, all with low or intermittent grazing pressure. In contrast, vegetative recruits were recorded at 19 populations and comprised at least 28% of plants measured. Resprouting confers some resilience to individuals, although repeated browsing restricts plant growth, limiting flowering and fruiting. Consistently heavily grazed populations also contain fewer plants. Although Eremophila stenophylla is secure in numerous populations with low grazing pressure, it qualifies as Vulnerable under IUCN Red List criteria due to past and ongoing decline at more than half of its populations. Grazing relief is necessary to ensure the long-term persistence of these populations. We predict that similar trajectories apply to other semi-arid shrubs, and research is required to inform grazing management to avert local extinctions. Highlights • Eremophila stenophylla is a heavily-browsed, geographically restricted rangeland shrub. • Resprouting confers some resilience but browsing restricts plant growth, fecundity and recruitment. • Heavily grazed populations contain fewer plants. • Grazing relief is necessary to ensure long-term persistence of populations. • Palatable perennials are vulnerable to declines and research is needed to inform appropriate grazing management. [ABSTRACT FROM AUTHOR]

Abstract: Semi-arid succulent thicket in South Africa has experienced extensive livestock-induced transformation, reflected in extensive structural changes and loss of biodiversity, biomass and soil carbon. The ecological mechanisms contributing to this transformation are not fully understood but are believed to include the breakdown of ecosystem processes including litter production and decomposition, which are rate-limiting steps in nutrient cycling and incorporation of organic matter into the soil. In this study we investigated the effect of transformation on litter production and decomposition in succulent thicket. We measured litter production and decomposition of four dominant perennial woody plants (Euclea undulata, Pappea capensis, Portulacaria afra and Rhus longispina) across replicated fenceline contrasts. Litter production was measured over 14 months using mesh traps. Decomposition was measured over 15 months using a combination of litterbags and leaf packs. Litter production in succulent thicket was very high for a semi-arid system (approaching that of temperate forests), with the leaf- and stem-succulent P. afra contributing the largest component. Transformation caused a significant reduction in litter production at a landscape scale (4126 vs 2881 kg/ha/yr), primarily due to reduced cover of P. afra. Surprisingly, transformation had few significant effects on the rate of decomposition of litter, possibly due to a switch from biotic to abiotic decomposition processes. The perennial vegetation in succulent thicket, particularly P. afra, appears to play a critical role in the maintenance of the ecosystem by facilitating the incorporation of organic matter into soil. Transformation of succulent thicket leads to a disruption of the carbon cycle, ultimately resulting in degradation of the ecosystem. Successful restoration is likely to depend on increasing the rates of organic matter return to soils. P. afra is a potential carbon restoration pump as it is both drought-resistant and easily propagated from cuttings. [Copyright &y& Elsevier]