Naomi Davis
University of Melbourne, School of BioSciences, Department Member
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Context There is concern about potential competition between non-native fallow deer (Dama dama) and livestock for food, particularly during times of low rainfall when pasture is scarce. Aims We aimed to estimate the extent to which a... more
Context There is concern about potential competition between non-native fallow deer (Dama dama) and livestock for food, particularly during times of low rainfall when pasture is scarce. Aims We aimed to estimate the extent to which a high-density fallow deer population (~37 deer per km2) competed with livestock for food during a severe drought on pastoral properties on the Liverpool Plains, New South Wales, Australia. Methods We collected rumen contents from 125 fallow deer shot from helicopters during control operations in June and August 2018, and used microhistology to quantify their diets. We then used the diet data to adjust published estimates of stock unit equivalence from farmed fallow deer. Fallow deer sex and age class abundances and stock unit equivalences were multiplied to estimate the grazing pressure of the fallow deer population pre- and post-control relative to recommended sheep and cattle stocking rates. Finally, we estimated density–impact relationships for fallow...
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Context Introduced sambar deer (Cervus unicolor) are increasing in south-eastern Australia, and both volunteer and contract ground-based shooters are being used by management agencies to control their undesirable impacts. However, little... more
Context Introduced sambar deer (Cervus unicolor) are increasing in south-eastern Australia, and both volunteer and contract ground-based shooters are being used by management agencies to control their undesirable impacts. However, little is known about the effectiveness and costs of volunteer and contract shooters for controlling deer populations in Australia. Aims We evaluated the effectiveness and costs of volunteer and contract ground-based shooters for controlling sambar deer and their impacts in a 5-year management program conducted in and around alpine peatlands in Alpine National Park, Victoria. Methods Ground-based shooting operations were organised in two blocks. Within each block, four ~4200-ha management units were delimited, of which two were randomly assigned as treatment (ground-based shooting) and two as non-treatment (no organised ground-based shooting). In the treatment units, ground-based shooting was conducted using either volunteers or contractors. Each shooting ...
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Context Of the six species of non-native deer present in Australia, the sambar deer is the largest and has been identified as a major threat to high-elevation peatlands in south-eastern Australia. However, little is known about sambar... more
Context Of the six species of non-native deer present in Australia, the sambar deer is the largest and has been identified as a major threat to high-elevation peatlands in south-eastern Australia. However, little is known about sambar deer activity in high-elevation peatlands. Aims The aims of this study were to quantify sambar deer activity (including wallowing) seasonally and daily in response to biotic and abiotic variables, and how activity was impacted by ground-based shooting. Methods To estimate sambar deer activity, camera traps were continuously deployed for 4 years in two ~4300-ha areas in Alpine National Park, Victoria, south-eastern Australia. One area was subject to management operations using ground-based shooting to target deer and the other was not. Monthly activity of sambar deer was modelled using biotic (woody vegetation cover), abiotic (snow depth, aspect, slope, distance to water, road and peatland) and management (treatment versus non-treatment) covariates. Add...
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Deer (Cervidae) are key components of many ecosystems and estimating deer abundance or density is important to understanding these roles. Many field methods have been used to estimate deer abundance and density, but the factors... more
Deer (Cervidae) are key components of many ecosystems and estimating deer abundance or density is important to understanding these roles. Many field methods have been used to estimate deer abundance and density, but the factors determining where, when, and why a method was used, and its usefulness, have not been investigated. We systematically reviewed journal articles published during 2004–2018 to evaluate spatio‐temporal trends in study objectives, methodologies, and deer abundance and density estimates, and determine how they varied with biophysical and anthropogenic attributes. We also reviewed the precision and bias of deer abundance estimation methods. We found 3,870 deer abundance and density estimates. Most estimates (58%) were for white‐tailed deer (Odocoileus virginianus), red deer (Cervus elaphus), and roe deer (Capreolus capreolus). The 6 key methods used to estimate abundance and density were pedestrian sign (track or fecal) counts, pedestrian direct counts, vehicular d...
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The file contains 8 columns and 31 rows. The first row contains the column headings and the remaining 30 rows are the data values arranged by year (i.e. one row for each of the 30 years of the study). The first column 'Year' is... more
The file contains 8 columns and 31 rows. The first row contains the column headings and the remaining 30 rows are the data values arranged by year (i.e. one row for each of the 30 years of the study). The first column 'Year' is the year the data relate to (first year is 1984, last year is 2013). The second column 'HunterCPUE' is the mean number of sambar deer shot per hunter per day in each of the 30 years. The third column 'nDingoScats' is the number of dingo scats collected in each of the 30 years. The fourth column 'nRedFoxScats' is the number of red fox scats collected in each of the 30 years. The fifth column 'nSambDingoScats' is the number of dingo scats collected in each year that contained sambar deer. The sixth column 'nSambRedFoxScats' is the number of red fox scats collected in each year that contained sambar deer. The seventh column 'SambFoxScatsPerc' is the percentage of red fox scats collected in each year that contained sambar deer. The eighth column 'SambDingoScatsPerc' is the percentage of red fox scats collected in each year that contained sambar deer
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The dingo (Canis dingo or C. familiaris, including hybrids with feral dogs) is the apex carnivore on mainland Australia. Fifteen non-native ungulate species have established wild populations in Australia. Dingoes are managed to reduce... more
The dingo (Canis dingo or C. familiaris, including hybrids with feral dogs) is the apex carnivore on mainland Australia. Fifteen non-native ungulate species have established wild populations in Australia. Dingoes are managed to reduce impacts on domestic ungulates, and introduced wild ungulates are managed to reduce impacts on natural ecosystems and to minimise competition with domestic ungulates. There is speculation about the extent to which (1) dingoes limit the abundances of introduced wild ungulates, and (2) introduced wild ungulates sustain dingo populations. We reviewed the literature to identify potential ecological interactions between dingoes and introduced wild ungulates, and to synthesise evidence for interactions between dingoes and each ungulate species (including the percentage frequency occurrence (%FO) of ungulates in dingo diets). Eleven of the 15 ungulate species were recorded in the diet of dingoes, with the highest %FO occurrences reported for feral goats (73%) ...
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Research Interests: Zoology, Biology, Ecology, Invasive Species, Canopy, and 4 morePredation, Fauna, Arthropod, and Endemic Island Species
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Invasive deer have undesirable impacts on native ecosystems. Culling is commonly used to reduce those impacts, but is expensive and sometimes controversial. It is therefore important to robustly assess how culling reduces the impacts of... more
Invasive deer have undesirable impacts on native ecosystems. Culling is commonly used to reduce those impacts, but is expensive and sometimes controversial. It is therefore important to robustly assess how culling reduces the impacts of invasive deer. We conducted a Before‐After Control‐Impact (BACI) experiment to determine how culling affects the impacts of invasive sambar deer Cervus unicolor in an endangered alpine peatland ecosystem in south‐eastern Australia. We established two blocks, each with four 4300‐ha experimental units, in which two units were randomly assigned to a treatment of deer culling and the other two were non‐treatment areas. Sambar deer relative abundance (faecal pellet count) and three impacts (ground degradation, pugging intensity and water turbidity) in three peatland features (peatlands, natural pools and sambar deer wallows) were surveyed before and after culling was implemented. We used four metrics to quantify the culling intensity in each treatment uni...
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Dataset and R code to reproduce the analyses and figures of the following publication:<br><br>Forsyth, D. M., S. Comte, N. E. Davis, A. J. Bengsen, S. D. Côté, D. G. Hewitt, N. Morellet, and A. Mysterud. 2022. Methodology... more
Dataset and R code to reproduce the analyses and figures of the following publication:<br><br>Forsyth, D. M., S. Comte, N. E. Davis, A. J. Bengsen, S. D. Côté, D. G. Hewitt, N. Morellet, and A. Mysterud. 2022. Methodology Matters When Estimating Deer Abundance: a Global Systematic Review and Recommendations for Improvements. Journal of Wildlife Management<br><br>
Biological invasions by large herbivores involve the establishment of novel interactions with the receiving mammalian carnivore community, but understanding these interactions is difficult due to the large spatiotemporal scales at which... more
Biological invasions by large herbivores involve the establishment of novel interactions with the receiving mammalian carnivore community, but understanding these interactions is difficult due to the large spatiotemporal scales at which such dynamics would occur. We quantified the functional responses of a native apex predator (the dingo (Canis familiaris), which includes wild dogs and their hybrids) and a non-native mesopredator (red fox; Vulpes vulpes) to an invading non-native ungulate (sambar deer; Cervus unicolor) in Australia. We predicted that the apex predator would exhibit a stronger functional response to increasing sambar deer abundance than the mesopredator. We used a state–space model to link two 30-year time series: (i) sambar deer abundance (hunter catch-per-unit-effort); and (ii) percentages of sambar deer in dingo (N = 4531) and fox (N = 5002) scats. Sambar deer abundance increased over fourfold during 1984–2013. The percentages of sambar deer in dingo and fox scats increased during this 30-year period, from nil in both species in 1984 to 8.2% in dingoes and 0.5% in foxes in 2013. Dingoes exhibited a much stronger functional response to increasing sambar deer abundance than foxes. The prediction that invading deer would be utilized more by the apex predator than by the mesopredator was therefore supported. The increasing abundance of sambar deer during the period 1984–2013 provided an increasingly important food source for dingoes. In contrast, the smaller red fox utilized sambar deer much less. Our study demonstrates that prey enrichment can be an important consequence of large herbivore invasions and that the effect varies predictably with the trophic position of the mammalian carnivores in the receiving community
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Context Monitoring spatial and temporal change in relative abundance using statistically powerful designs is a critical aspect of wildlife management. Many indices of relative abundance are available, but information regarding their... more
Context Monitoring spatial and temporal change in relative abundance using statistically powerful designs is a critical aspect of wildlife management. Many indices of relative abundance are available, but information regarding their influence on statistical power is limited. Aims We compared the statistical power associated with occurrence-based and frequency-based indices derived from faecal pellet counts and camera trapping to detect changes in the activity of five mammalian herbivores. Methods We deployed camera traps and counted faecal pellets in native vegetation subjected to four management treatments in south-eastern Australia. We used simulation coupled with generalised linear mixed models to investigate the statistical power associated with a range of effect sizes for each combination of species, survey method and data type. Key results The index derived from camera frequency data provided the greatest statistical power to detect species’ responses and was the only index ca...
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To understand the recent elevational range expansion of European rabbits (Oryctolagus cuniculus) with declining snow cover and earlier snow thaw we examined their diet in relation to that of long-term residents, common wombats (Vombatus... more
To understand the recent elevational range expansion of European rabbits (Oryctolagus cuniculus) with declining snow cover and earlier snow thaw we examined their diet in relation to that of long-term residents, common wombats (Vombatus ursinus). The colonisation of eastern Australia by rabbits was effectively completed by 1910 when they reached an elevation of 1500 m (the winter snowline). Rabbits began to penetrate higher elevations only from the 1970s in association with anthropogenic habitat modification. Since 2011, rabbits have occupied elevations to the alpine treeline (~1850 m) throughout the year without the ameliorating presence of infrastructure or anthropogenically modified vegetation. Rabbits and wombats are both grazers preferring grasses (largely inaccessible beneath winter snow) and are spatially restricted in their foraging by their need to return to their burrows. Wombats used a much wider foraging range, enabling them to select preferred food. Rabbits, with a much...
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Habitat use is the most common dimension along which sympatric species partition resources to reduce competition. We conducted faecal pellet counts at Wilsons Promontory National Park, Victoria, to examine habitat use by an assemblage of... more
Habitat use is the most common dimension along which sympatric species partition resources to reduce competition. We conducted faecal pellet counts at Wilsons Promontory National Park, Victoria, to examine habitat use by an assemblage of mammalian herbivores with disparate evolutionary histories and varying body size: introduced European rabbit (Oryctolagus cuniculus) and hog deer (Axis porcinus), and native eastern grey kangaroo (Macropus giganteus), swamp wallaby (Wallabia bicolor) and common wombat (Vombatus ursinus). Overlap in habitat use was low between four pairs of species, suggesting spatial partitioning of resources to reduce the potential for interspecific competition. More generally, however, overlap in habitat use was high, particularly between native and introduced grazers. These results indicate the potential for competition if resources were limiting and suggest that assemblages of species with independent evolutionary histories have inherently less resource partitio...
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Context Restoration of disturbed vegetation communities commonly involves altering vegetation composition and structure, attributes that can influence the suitability of habitat for fauna. Feedbacks may occur whereby changes to the... more
Context Restoration of disturbed vegetation communities commonly involves altering vegetation composition and structure, attributes that can influence the suitability of habitat for fauna. Feedbacks may occur whereby changes to the vegetation affect mammalian herbivores, and unintended changes may prevent managers from achieving conservation goals. Aims To understand how vegetation management affects habitat use by five mammalian herbivores, namely eastern grey kangaroo (Macropus giganteus), swamp wallaby (Wallabia bicolor), common wombat (Vombatus ursinus), European rabbit (Oryctolagus cuniculus) and hog deer (Axis porcinus). Methods A management experiment (mechanical slashing of the encroaching shrub Leptospermum laevigatum) at Wilsons Promontory National Park, Australia, created slashed swales in addition to untreated dune and scrub woodland. In each vegetation stratum, we estimated the cover of L. laevigatum and quantified herbivore abundance by counting the standing crop of fa...
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Research Interests: Fluoride, Biology, Diet, Ecology, Medicine, and 15 moreBiological Sciences, Aluminum, Environmental Sciences, Animals, Adverse Effects of Fluoride, Herbivory, Fluorides, CHEMICAL SCIENCES, Macropodidae, Industrial Waste, Interspecific competition, Environmental Exposure, Herbivore, Herbivore Diet, and Omnivore
The accuracy of population abundance estimates of mammalian herbivores from faecal pellet counts is potentially affected by pellet decay. We collected fresh pellet groups from hog deer (Axis porcinus), European rabbit (Oryctolagus... more
The accuracy of population abundance estimates of mammalian herbivores from faecal pellet counts is potentially affected by pellet decay. We collected fresh pellet groups from hog deer (Axis porcinus), European rabbit (Oryctolagus cuniculus), eastern grey kangaroo (Macropus giganteus), swamp wallaby (Wallabia bicolor) and common wombat (Vombatus ursinus) (n = 300 per species) at Wilsons Promontory National Park, Victoria, Australia. We deposited five pellet groups per species per month within each of five vegetation types in the park, then monitored pellet group decay over 24 months. We demonstrate that age estimation of pellet groups was inaccurate and is unlikely to improve the efficiency of pellet counts. We present habitat- and species-specific estimates of pellet and pellet group decay using two measures: decay rate (the proportion of pellets surviving per unit of time); and mean time to decay. We explain how our data can be used to optimise faecal pellet count design, and to i...
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Supplementary material for the following publication in the Journal of Wildlife Management:<br>Forsyth D.M., Comte S., Davis N.E., Bengsen A.J., Cote S.D., Hewitt D.G., Morellet N. and Mysterud A. (2022) Methodology Matters When... more
Supplementary material for the following publication in the Journal of Wildlife Management:<br>Forsyth D.M., Comte S., Davis N.E., Bengsen A.J., Cote S.D., Hewitt D.G., Morellet N. and Mysterud A. (2022) Methodology Matters When Estimating Deer Abundance: a Global Systematic Review and Recommendations for Improvements. Journal of Wildlife Management
Deer are among the world’s most successful invasive mammals and can have substantial deleterious impacts on natural and agricultural ecosystems. Six species have established wild populations in Australia, and the distributions and... more
Deer are among the world’s most successful invasive mammals and can have substantial deleterious impacts on natural and agricultural ecosystems. Six species have established wild populations in Australia, and the distributions and abundances of some species are increasing. Approaches to managing wild deer in Australia are diverse and complex, with some populations managed as ‘game’ and others as ‘pests’. Implementation of cost-effective management strategies that account for this complexity is hindered by a lack of knowledge of the nature, extent and severity of deer impacts. To clarify the knowledge base and identify research needs, we conducted a systematic review of the impacts and management of wild deer in Australia. Most wild deer are in south-eastern Australia, but bioclimatic analysis suggested that four species are well suited to the tropical and subtropical climates of northern Australia. Deer could potentially occupy most of the continent, including parts of the arid inte...
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Biological invasions by large herbivores involve the establishment of novel interactions with the receiving mammalian carnivore community, but understanding these interactions is difficult due to the large spatiotemporal scales at which... more
Biological invasions by large herbivores involve the establishment of novel interactions with the receiving mammalian carnivore community, but understanding these interactions is difficult due to the large spatiotemporal scales at which such dynamics would occur. We quantified the functional responses of a native apex predator (the dingo (Canis familiaris), which includes wild dogs and their hybrids) and a non-native mesopredator (red fox; Vulpes vulpes) to an invading non-native ungulate (sambar deer; Cervus unicolor) in Australia. We predicted that the apex predator would exhibit a stronger functional response to increasing sambar deer abundance than the mesopredator. We used a state–space model to link two 30-year time series: (i) sambar deer
abundance (hunter catch-per-unit-effort); and (ii) percentages of sambar deer in dingo (N = 4531) and fox (N = 5002) scats. Sambar deer abundance increased over fourfold during 19842013. The percentages of sambar deer in dingo and fox scats increased during this 30-year period, from nil in both species in 1984 to 8.2% in dingoes and 0.5% in foxes in 2013. Dingoes exhibited a much stronger functional response to increasing sambar deer abundance than foxes. The prediction that invading deer would be utilized more by the apex predator than
by the mesopredator was therefore supported. The increasing abundance of sambar deer during the period 19842013 provided an increasingly important food source for dingoes. In contrast, the smaller red fox utilized sambar deer much less. Our study demonstrates that prey enrichment can be an important consequence of large
herbivore invasions and that the effect varies predictably with the trophic position of the mammalian carnivores in the receiving community.
abundance (hunter catch-per-unit-effort); and (ii) percentages of sambar deer in dingo (N = 4531) and fox (N = 5002) scats. Sambar deer abundance increased over fourfold during 19842013. The percentages of sambar deer in dingo and fox scats increased during this 30-year period, from nil in both species in 1984 to 8.2% in dingoes and 0.5% in foxes in 2013. Dingoes exhibited a much stronger functional response to increasing sambar deer abundance than foxes. The prediction that invading deer would be utilized more by the apex predator than
by the mesopredator was therefore supported. The increasing abundance of sambar deer during the period 19842013 provided an increasingly important food source for dingoes. In contrast, the smaller red fox utilized sambar deer much less. Our study demonstrates that prey enrichment can be an important consequence of large
herbivore invasions and that the effect varies predictably with the trophic position of the mammalian carnivores in the receiving community.
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Habitat use is the most common dimension along which sympatric species partition resources to reduce competition.Weconducted faecal pellet counts at Wilsons Promontory National Park, Victoria, to examine habitat use by an assemblage of... more
Habitat use is the most common dimension along which sympatric species partition resources to reduce
competition.Weconducted faecal pellet counts at Wilsons Promontory National Park, Victoria, to examine habitat use by an
assemblage of mammalian herbivores with disparate evolutionary histories and varying body size: introduced European
rabbit (Oryctolagus cuniculus) and hog deer (Axis porcinus), and native eastern grey kangaroo (Macropus giganteus),swamp
wallaby (Wallabia bicolor) and common wombat (Vombatus ursinus). Overlap in habitat use was low between four pairs of
species, suggesting spatial partitioning of resources to reduce the potential for interspecific competition. More generally,
however, overlap in habitat use was high, particularly between native and introduced grazers. These results indicate the
potential for competition if resources were limiting and suggest that assemblages of species with independent evolutionary
histories have inherently less resource partitioning to facilitate coexistence than assemblages of species with common
evolutionary histories. Despite evidence of high overlap in habitat use between native and introduced species at a broad scale,
and variation in the competitive ability of species, coexistence was likely facilitated by niche complementarity, including
temporal and fine-scale partitioning of spatial resources. There was no relationship between body size and the diversity of
habitats used. In contemporary assemblages of native and introduced species, evolutionary history is likely to have a strong
influence on resource partitioning.
competition.Weconducted faecal pellet counts at Wilsons Promontory National Park, Victoria, to examine habitat use by an
assemblage of mammalian herbivores with disparate evolutionary histories and varying body size: introduced European
rabbit (Oryctolagus cuniculus) and hog deer (Axis porcinus), and native eastern grey kangaroo (Macropus giganteus),swamp
wallaby (Wallabia bicolor) and common wombat (Vombatus ursinus). Overlap in habitat use was low between four pairs of
species, suggesting spatial partitioning of resources to reduce the potential for interspecific competition. More generally,
however, overlap in habitat use was high, particularly between native and introduced grazers. These results indicate the
potential for competition if resources were limiting and suggest that assemblages of species with independent evolutionary
histories have inherently less resource partitioning to facilitate coexistence than assemblages of species with common
evolutionary histories. Despite evidence of high overlap in habitat use between native and introduced species at a broad scale,
and variation in the competitive ability of species, coexistence was likely facilitated by niche complementarity, including
temporal and fine-scale partitioning of spatial resources. There was no relationship between body size and the diversity of
habitats used. In contemporary assemblages of native and introduced species, evolutionary history is likely to have a strong
influence on resource partitioning.
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Deer are among the world's most successful invasive mammals and can have substantial deleterious impacts on natural and agricultural ecosystems. Six species have established wild populations in Australia, and the distributions and... more
Deer are among the world's most successful invasive mammals and can have substantial deleterious impacts on natural and agricultural ecosystems. Six species have established wild populations in Australia, and the distributions and abundances of some species are increasing. Approaches to managing wild deer in Australia are diverse and complex, with some populations managed as 'game' and others as 'pests'. Implementation of cost-effective management strategies that account for this complexity is hindered by a lack of knowledge of the nature, extent and severity of deer impacts. To clarify the knowledge base and identify research needs, we conducted a systematic review of the impacts and management of wild deer in Australia. Most wild deer are in southeastern Australia, but bioclimatic analysis suggested that four species are well suited to the tropical and subtropical climates of northern Australia. Deer could potentially occupy most of the continent, including parts of the arid interior. The most significant impacts are likely to occur through direct effects of herbivory, with potentially cascading indirect effects on fauna and ecosystem processes. However, evidence of impacts in Australia is largely observational, and few studies have experimentally partitioned the impacts of deer from those of sympatric native and other introduced herbivores. Furthermore, there has been little rigorous testing of the efficacy of deer management in Australia, and our understanding of the deer ecology required to guide deer management is limited. We identified the following six priority research areas: (i) identifying long-term changes in plant communities caused by deer; (ii) understanding interactions with other fauna; (iii) measuring impacts on water quality; (iv) assessing economic impacts on agriculture (including as disease vectors); (v) evaluating efficacy of management for mitigating deer impacts; and (vi) quantifying changes in distribution and abundance. Addressing these knowledge gaps will assist the development and prioritisation of cost-effective management strategies and help increase stakeholder support for managing the impacts of deer on Australian ecosystems.
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To understand the recent elevational range expansion of European rabbits (Oryctolagus cuniculus) with declining snow cover and earlier snow thaw we examined their diet in relation to that of long-term residents, common wombats (Vombatus... more
To understand the recent elevational range expansion of European rabbits (Oryctolagus cuniculus) with declining snow cover and earlier snow thaw we examined their diet in relation to that of long-term residents, common wombats (Vombatus ursinus). The colonisation of eastern Australia by rabbits was effectively completed by 1910 when
they reached an elevation of 1500m(the winter snowline). Rabbits began to penetrate higher elevations only from the 1970s in association with anthropogenic habitat modification. Since 2011, rabbits have occupied elevations to the alpine treeline (~1850 m) throughout the year without the ameliorating presence of infrastructure or anthropogenically modified vegetation. Rabbits and wombats are both grazers preferring grasses (largely inaccessible beneath winter snow) and are spatially restricted in their foraging by their need to return to their burrows. Wombats used a much wider foraging range, enabling them to select preferred food. Rabbits, with a much smaller range, were constrained in their choice of forage mainly to plants that projected above the snow. Unexpectedly, rabbits fed intensively on leaves of eucalypts, food not typically consumed in substantial quantities by this species. These leaves, on stems regenerating after fire, will diminish
in availability as stems mature, possibly halting the range expansion of rabbits.
they reached an elevation of 1500m(the winter snowline). Rabbits began to penetrate higher elevations only from the 1970s in association with anthropogenic habitat modification. Since 2011, rabbits have occupied elevations to the alpine treeline (~1850 m) throughout the year without the ameliorating presence of infrastructure or anthropogenically modified vegetation. Rabbits and wombats are both grazers preferring grasses (largely inaccessible beneath winter snow) and are spatially restricted in their foraging by their need to return to their burrows. Wombats used a much wider foraging range, enabling them to select preferred food. Rabbits, with a much smaller range, were constrained in their choice of forage mainly to plants that projected above the snow. Unexpectedly, rabbits fed intensively on leaves of eucalypts, food not typically consumed in substantial quantities by this species. These leaves, on stems regenerating after fire, will diminish
in availability as stems mature, possibly halting the range expansion of rabbits.
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Dingoes/wild dogs (Canis dingo/familiaris) and red foxes (Vulpes vulpes) are widespread carnivores in southern Australia and are controlled to reduce predation on domestic livestock and native fauna. We used the occurrence of food items... more
Dingoes/wild dogs (Canis dingo/familiaris) and red foxes (Vulpes vulpes) are widespread carnivores in southern Australia and are controlled to reduce predation on domestic livestock and native fauna. We used the occurrence of food items in 5875 dingo/wild dog scats and 11,569 fox scats to evaluate interspecific and geographic differences in the diets of these species within nine regions of Victoria, southeastern Australia. The nine regions encompass a wide variety of ecosystems. Diet overlap between dingoes/wild dogs and foxes varied among regions, from low to near complete overlap. The diet of foxes was broader than dingoes/wild dogs in all but three regions, with the former usually containing more insects , reptiles and plant material. By contrast, dingoes/wild dogs more regularly consumed larger mammals, supporting the hypothesis that niche partitioning occurs on the basis of mammalian prey size. The key mammalian food items for dingoes/wild dogs across all regions were black wal...
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The use of high elevations with deep snow cover presents a challenge to mammalian herbivores, which is exacerbated by subalpine vegetation dynamics such as slow regrowth following disturbance. We postulated that post-fire responses of... more
The use of high elevations with deep snow cover presents a challenge to mammalian herbivores, which is exacerbated by subalpine vegetation dynamics such as slow regrowth following disturbance. We postulated that post-fire responses of common wombats (Vombatus ursinus) at high elevations would differ from those at low elevations. We examined the winter diet of common wombats in the Snowy Mountains in the decade after fire in burnt and unburnt areas and compared our results to published diet studies from low elevations. Optimal foraging theory predicts that as food resources become scarce herbivores respond by widening their choice of foods, yet we found that wombats have only marginally wider dietary breadth at higher than at lower elevations in terms of plant forms and diet breadth in terms of species was not greater. The use of shrubs and the tall herb Dianella tasmanica enables wombats to reduce the energetic costs of digging for food in snow. Able to survive fire in a burrow, the...
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... Page 3. proportion of plant epidermal fragments identified within each category of Levels 1-5 for each of the five herbivore species. We calculated bootstrapped 95% confidence intervals for these means with Microsoft ExcelÔ using the... more
... Page 3. proportion of plant epidermal fragments identified within each category of Levels 1-5 for each of the five herbivore species. We calculated bootstrapped 95% confidence intervals for these means with Microsoft ExcelÔ using the Poptools add-in (Hood 2005). ...
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... Anthony and Smith (1974) examined diets of mule deer (Odocoileus hemionus) and white-tailed deer (O. virginianus) and concluded that composition estimates were similar, but grasses were overestimated by the microscopic technique, and... more
... Anthony and Smith (1974) examined diets of mule deer (Odocoileus hemionus) and white-tailed deer (O. virginianus) and concluded that composition estimates were similar, but grasses were overestimated by the microscopic technique, and herbs, flowers, and fruit were ...
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ABSTRACT European hares (Lepus europaeus) are grazers and open grassland specialists that are replaced in mountain areas of their natural range in the northern hemisphere by browsing/intermediate feeding mountain hares (Lepus timidus),... more
ABSTRACT European hares (Lepus europaeus) are grazers and open grassland specialists that are replaced in mountain areas of their natural range in the northern hemisphere by browsing/intermediate feeding mountain hares (Lepus timidus), but in their introduced range in the southern hemisphere, occupy the alpine zone. We used micro-histological identification of plant fragments and germination of seeds in faecal pellets of L. europaeus from the Snowy Mountains, Australia, to determine diet. We asked whether diet shifted and/or diet breadth expanded in response to seasonally reduced food availability, particularly during winter. If so, did the constraints of food availability in the alpine zone lead to the diet mirroring that of L. timidus in its native alpine habitat. The diet of L. europaeus was dominated by grasses, herbs and shrubs. The main diet items in summer were grasses (70 %) and herbs (28 %). Grasses declined in the diet between summer and autumn when herbs increased to co-dominance, with a further change after establishment of the winter snowpack to a greater preponderance of shrubs (43 % compared with a maximum of 3 % in snow-free months). L. europaeus selected a wider range of plants in winter (59 species compared with 39 in summer) and diet was significantly more variable in winter than in autumn or summer (and in autumn than summer). We concluded that the persistence of L. europaeus in alpine areas of the southern hemisphere is testament to their ability to expand their dietary breadth to occupy mountain climatic zones normally occupied by L. timidus.