scholarly journals Change in the diet of sooty owls (Tyto tenebricosa) since European settlement: from terrestrial to arboreal prey and increased overlap with powerful owls

2006 ◽  
Vol 33 (1) ◽  
pp. 17 ◽  
Author(s):  
Rohan J. Bilney ◽  
Raylene Cooke ◽  
John White
Keyword(s):  
Monitoring System ◽  
Vulpes Vulpes ◽  
Control Strategies ◽  
Large Array ◽  
Dietary Overlap ◽  
Mammal Species ◽  
Critical Weight ◽  
Terrestrial Mammal ◽  
European Settlement ◽  
Fox Control

The current diet of the sooty owl (Tyto tenebricosa) was determined by analysing freshly regurgitated pellets collected beneath their roosting sites in East Gippsland, Victoria. Comparisons were then made with: (i) prehistoric and historic diet from bone deposits found in cave roosts, and (ii) diet of a sympatric owl species, the powerful owl (Ninox strenua). Sooty owls consumed a large array of terrestrial mammal species before European settlement, but only three terrestrial species were detected in their current diet, a reduction of at least eight species since European settlement. To compensate, sooty owls have increased their consumption of arboreal prey from 55% to 81% of their diet. Arboreal species are also a major component of the powerful owl diet and this prey shift by sooty owls has increased dietary overlap between these two species. Predation by foxes (Vulpes vulpes) and other feral species is likely to have reduced the amount of terrestrial prey available to sooty owls since European settlement. Investigation of changes in the diet of sooty owls may offer a unique monitoring system for evaluating the ability of fox-control strategies to influence increases in numbers of critical-weight-range mammals.

The status of mammals in the North Kimberley, Western Australia

2007 ◽  
Vol 29 (1) ◽  
pp. 1 ◽  
Author(s):  
A.N. Start ◽  
A.A.. Burbidge ◽  
N.L. McKenzie ◽  
C. Palmer
Keyword(s):  
Exotic Species ◽  
Fire Regimes ◽  
Mammalian Fauna ◽  
Mammal Species ◽  
Critical Weight ◽  
Terrestrial Mammal ◽  
The North ◽  
European Settlement ◽  
The Status ◽  
Rocky Habitats

The mammalian fauna of the North Kimberley bioregion has been cited as ?intact? because 1970s and 1980s surveys showed that all terrestrial mammal species known at European settlement were extant. This assumption was tested in 2003/4 by re-surveying 16 of the most diverse sites sampled in earlier surveys of three mainland areas and four islands. Most Critical Weight Range species were re-located at many sites and some were found at sites where they were previously unknown. Most differences between early surveys and this survey are probably artifacts of limited survey intensity. However, the region is not exempt from processes associated with decline elsewhere, particularly effects of changed fire regimes and invasion by exotic species, and species of non-rocky habitats may be more vulnerable. Small granivorous rodents were notably scarce.

scholarly journals Geographical Gradients in Argentinean Terrestrial Mammal Species Richness and Their Environmental Correlates

2012 ◽  
Vol 2012 ◽  
pp. 1-13
Author(s):  
Ana L. Márquez ◽  
Raimundo Real ◽  
Marta S. Kin ◽  
José Carlos Guerrero ◽  
Betina Galván ◽  
...  
Keyword(s):  
Species Richness ◽  
Variation Partitioning ◽  
Spatial Form ◽  
Spatial Filters ◽  
Mammal Species ◽  
Terrestrial Mammal ◽  
Explanatory Variables ◽  
Longitudinal Gradients ◽  
Partial Correlations ◽  
Partitioning Procedure

We analysed the main geographical trends of terrestrial mammal species richness (SR) in Argentina, assessing how broad-scale environmental variation (defined by climatic and topographic variables) and the spatial form of the country (defined by spatial filters based on spatial eigenvector mapping (SEVM)) influence the kinds and the numbers of mammal species along these geographical trends. We also evaluated if there are pure geographical trends not accounted for by the environmental or spatial factors. The environmental variables and spatial filters that simultaneously correlated with the geographical variables and SR were considered potential causes of the geographic trends. We performed partial correlations between SR and the geographical variables, maintaining the selected explanatory variables statistically constant, to determine if SR was fully explained by them or if a significant residual geographic pattern remained. All groups and subgroups presented a latitudinal gradient not attributable to the spatial form of the country. Most of these trends were not explained by climate. We used a variation partitioning procedure to quantify the pure geographic trend (PGT) that remained unaccounted for. The PGT was larger for latitudinal than for longitudinal gradients. This suggests that historical or purely geographical causes may also be relevant drivers of these geographical gradients in mammal diversity.

Camera trap evidence of red fox (Vulpes vulpes) predation attempts on adult macropods

2017 ◽  
Vol 23 (3) ◽  
pp. 302 ◽  
Author(s):  
Paul D. Meek ◽  
Jason Wishart
Keyword(s):  
Pest Management ◽  
Vulpes Vulpes ◽  
Red Fox ◽  
New South ◽  
Camera Trap ◽  
Camera Traps ◽  
Critical Weight ◽  
South Wales ◽  
Photographic Evidence ◽  
Management Project

Camera traps provide a novel and quasicovert method of gathering information on animal behaviour that may otherwise remain undetected without sophisticated and expensive filming equipment. In a rangelands pest management project at Mt Hope in the central west of New South Wales, Australia, we recorded foxes seemingly hunting kangaroos on three occasions. While we did not record direct instances of predation, our observations provide camera trap photographic evidence suggesting that foxes will attempt to tackle mammals above the critical weight range, including large macropod species such as western grey kangaroos.

Conservation status of mammals and birds in southwestern Australian forests. I. Is there evidence of direct links between forestry practices and species decline and extinction?

1998 ◽  
Vol 4 (4) ◽  
pp. 296 ◽  
Author(s):  
M. C. Calver ◽  
J. Dell
Keyword(s):  
Negative Impact ◽  
Conservation Status ◽  
Bird Species ◽  
Fire Regimes ◽  
Personal Identification ◽  
Base Line ◽  
Mammal Species ◽  
Current Conservation ◽  
Forestry Practices ◽  
European Settlement

Sixteen mammal species and 22 bird species whose distributions extended into southwestern Australian forests before European settlement have been listed as threatened at some time in Commonwealth legislation, State legislation, or action plans of Environment Australia or its predecessors. Confident assessment of the causes of conservation status is hampered by poor base-line data, few studies of putative impacts and a preponderance of circumstantial or anecdotal rather than experimental evidence. However, introduced foxes were Implicated In the current conservation status of 62% of the mammal species recognized, while 44% of them were negatively impacted by feral cats, 44% by agricultural clearing and 44% by changed fire regimes. Forestry practices were impllcated in the conservation status of only one mammal species. For the bird species recognized, changed fire regimes had the greatest negative impact (45% affected), agricultural clearing affected 41%, draining of wetlands affected 32% and grazing by livestock affected 22%. Forestry practices were not directly implicated in the conservation status of any bird species. While these results suggest that forestry has had minimal direct impact on the mammals and birds of the forests, the conclusion should be treated cautiously because of the poor data. While awaiting a rigorous evaluation, we argue for a strong precautionary approach to forestry in the region. With proper forest management and sound sylvicultural [sic] treatment there is no reason why there should not be built up on the wreckage of the once splendid forests of Western Australia tended forests which will yield for all time 100 cubic feet of timber per acre per year. Lane-Poole (1920). There are many reasons why Australian environmentalists would like to end logging in native forests. The preservation of wilderness, aesthetics, an almost religious identification with old growth forests and the conservation of forest wildlife figure importantly in environmental efforts to restrict logging. Wilderness and a personal identification with trees and undisturbed forests are fundamentally incompatible with logging. Recher (1996).

scholarly journals Aboriginal knowledge of the mammals of the central deserts of Australia

1988 ◽  
Vol 15 (1) ◽  
pp. 9 ◽  
Author(s):  
A. A. Burbidge ◽  
K. A. Johnson ◽  
P. J. Fuller ◽  
R. I. Southgate
Keyword(s):  
Aboriginal People ◽  
Geographic Range ◽  
Mammal Species ◽  
Terrestrial Mammal ◽  
Sudden Loss ◽  
The Past ◽  
Mammal Fauna ◽  
Profound Knowledge ◽  
Preferred Habitat ◽  
The Subject

More than one-third of the terrestrial mammal species of the central deserts of Australia have vanished in the past 50 years. Few of these have been the subject of even preliminary scientific study, and data as basic as geographic range and preferred habitat are lacking for many species. Aborigines, many of whom lived traditionally in the central deserts until recently, still retain a profound knowledge of the mammals, but this knowledge, too, is fast disappearing. Aboriginal people living in communities scattered through and around the edges of the 1645 000 km2 of the study area, comprising the Great Sandy, Little Sandy, Tanami, Gibson and Great Victoria Deserts and the Central Ranges district, were shown museum skins and asked to provide information about local names, current and past status, and aspects of biology and ecology. Most species, including some thought to have become extinct early this century, persisted in the deserts until 30–50 years ago. New data are presented on former distribution and on the biology and ecology of many species. The mammal fauna of the central deserts was richer and more widespread than generally believed, but the area has suffered a massive and sudden loss of species, probably unparalleled in extent elsewhere in Australia.

Diet analysis of mammals, raptors and reptiles in a complex predator assemblage in the Blue Mountains, eastern Australia

2011 ◽  
Vol 59 (5) ◽  
pp. 295 ◽  
Author(s):  
Jack H. Pascoe ◽  
Robert C. Mulley ◽  
Ricky Spencer ◽  
Rosalie Chapple
Keyword(s):  
Field Study ◽  
Canis Lupus ◽  
Vulpes Vulpes ◽  
Diet Overlap ◽  
Diet Analysis ◽  
Critical Weight ◽  
Blue Mountains ◽  
Eastern Australia ◽  
High Level ◽  
Wild Dogs

South-east Australia has a complex predator assemblage which has historically been vulnerable to introduced species. This is the first Australian field study to analyse samples from members of the families Canidae, Dasyuridae, Strigidae, and Varanidae to describe the diet and diet overlap between these predators. Samples were collected opportunistically and hair and bone analysis was used to identify the content of samples. Wild dogs (Canis lupus) and lace monitors (Varanus varius) predominantly consumed large mammalian prey, which contributed to the high level of diet overlap (Ojk = 0.79) between these two species. Foxes (Vulpes vulpes) and spotted-tailed quolls (Dasyurus maculatus) also had a high level of diet overlap (Ojk = 0.76), a result of their diets containing a high proportion of medium-sized mammals. The diet of wild dogs and foxes showed moderate overlap (Ojk = 0.59), and foxes were more likely to prey on species within the critical weight range than on macropods, which made up a high proportion of the diet of wild dogs. These data confirm that significant diet overlap can occur between predators from different taxonomic classes and further investigation of potential competition will be important to ongoing management.

The good, the bad, and the ugly: which Australian terrestrial mammal species attract most research?

Mammal Review ◽  
2016 ◽  
Vol 46 (4) ◽  
pp. 241-254 ◽  
Author(s):  
Patricia A. Fleming ◽  
Philip W. Bateman
Keyword(s):  
Mammal Species ◽  
Terrestrial Mammal

The fate of dried meat baits laid for fox control: the effects of bait presentation on take by foxes and non-target species, and on caching by foxes

2002 ◽  
Vol 29 (4) ◽  
pp. 371 ◽  
Author(s):  
P. C. Thomson ◽  
N. E. Kok
Keyword(s):  
Western Australia ◽  
Vulpes Vulpes ◽  
Lower Proportion ◽  
Potential Hazard ◽  
Target Species ◽  
Red Foxes ◽  
Mixed Farming ◽  
Radio Transmitters ◽  
Fox Control

Non-toxic, dried meat baits (45 g) containing small radio-transmitters were laid on cleared sandplots in mixed farming and grain-growing areas in Western Australia. Baits were either buried, tethered by wire trace to a hidden peg, or simply laid untethered on the surface. Baits were exposed for 1 night only and new transects were established each day. Data were available on 1521 baits. Red foxes (Vulpes vulpes) visited 23% of plots and took baits from 64% of those visited. Unburied baits (both tethered and untethered) were taken significantly more frequently than the buried baits. Of all baits taken by foxes, 25% were cached. Foxes were more likely to cache buried baits than either tethered or untethered baits. Excluding baits taken to cubs, foxes cached baits 3–380 m (mean 87�m) from their original locations. Some baits were carried to cub dens up to 1.25�km away. The fate of 27�cached baits was monitored for varying periods. Of these baits, 59% were later eaten by foxes, most within 3�days. Non-target species took 3% of the baits on offer. Birds were the most common non-target animals to take baits, and in some cases dropped baits up to 400 m away. In terms of takes relative to visits, most takes by birds were of the untethered baits (88%, cf. 33% for tethered, 17% for buried baits). Compared with other baits, a significantly lower proportion of the untethered baits that were taken by birds was actually eaten. Baits cached by foxes and baits moved by birds represent a potential hazard to farm dogs and vulnerable fauna. Recommendations on bait presentation, distance restrictions, and likely risk to farm dogs and non-target species are discussed.

Potential competition between two top-order predators following a dramatic contraction in the diversity of their prey base

2011 ◽  
Vol 61 (1) ◽  
pp. 29-47 ◽  
Author(s):  
Raylene Cooke ◽  
Rohan Bilney ◽  
John White
Keyword(s):  
Habitat Management ◽  
Mammalian Species ◽  
Dietary Overlap ◽  
Study Region ◽  
Terrestrial Mammals ◽  
Potential Competition ◽  
European Settlement ◽  
Eastern Australia ◽  
Significant Divergence ◽  
Potential Resource

AbstractTwo sympatric native top-order predators, the sooty owl (Tyto tenebricosa tenebricosa) and powerful owl (Ninox strenua) coexist throughout much of their range in south-eastern Australia. Following European settlement, however, major changes in resource availability for these predators potentially resulted in increased competition, especially for food. This study examined ecological attributes of both species, including intersexual differences in the sooty owl, potential resource partitioning and whether competition may be occurring. Dietary overlap was high between female sooty owls and powerful owls (0.90), compared to overlap between male sooty owls and powerful owls (0.67), with three mammalian species contributing over 74% of their diets. Sooty and powerful owls coexisted throughout the study region, regularly roosting within the same vegetation types, and in similar locations, although microhabitat differences were apparent. Sooty owls displayed aseasonal breeding, although a peak in fledging in spring coincided with powerful owl breeding. Both species exclusively nested in similar size mountain grey gums (Eucalyptus cypellocarpa), however, hollow characteristics differed slightly. Significant divergence along a single niche dimension was not detected between powerful and sooty owls, as they had similar diets, habitat usage and activity times, potentially resulting in competition. Reproductive output was low for both species, however, the degree to which competitive interactions influenced this remains unknown. To minimise potential competition, longterm feral predator control and improved habitat management is recommended to increase the density and diversity of small terrestrial mammals, as this should result in diversification of the sooty owl diet, reducing dietary overlap with powerful owls.

The effectiveness and cost of camera traps for surveying small reptiles and critical weight range mammals: a comparison with labour-intensive complementary methods

2015 ◽  
Vol 42 (5) ◽  
pp. 414 ◽  
Author(s):  
Dustin J. Welbourne ◽  
Christopher MacGregor ◽  
David Paull ◽  
David B. Lindenmayer
Keyword(s):  
Monitoring Program ◽  
Camera Traps ◽  
Camera Trapping ◽  
Mammal Species ◽  
Critical Weight ◽  
Complementary Methods ◽  
Incidence Data ◽  
Trapping Method ◽  
The Difference

Context Biodiversity studies often require wildlife researchers to survey multiple species across taxonomic classes. To detect terrestrial squamate and mammal species, often multiple labour-intensive survey techniques are required. Camera traps appear to be more effective and cost-efficient than labour-intensive methods for detecting some mammal species. Recent developments have seen camera traps used for detecting terrestrial squamates. However, the performance of camera traps to survey terrestrial squamate and mammal species simultaneously has not been evaluated. Aim We compared the effectiveness and financial cost of a camera trapping method capable of detecting small squamates and mammals with a set of labour-intensive complementary methods, which have been used in a long-term monitoring program. Methods We compared two survey protocols: one employed labour-intensive complementary methods consisting of cage traps, Elliott traps and artificial refuges; the second utilised camera traps. Comparisons were made of the total number of species detected, species detectability, and cost of executing each type of survey. Key results Camera traps detected significantly more target species per transect than the complementary methods used. Although camera traps detected more species of reptile per transect, the difference was not significant. For the initial survey, camera traps were more expensive than the complementary methods employed, but for realistic cost scenarios camera traps were less expensive in the long term. Conclusions Camera traps are more effective and less expensive than the complementary methods used for acquiring incidence data on terrestrial squamate and mammal species. Implications The camera trapping method presented does not require customised equipment; thus, wildlife managers can use existing camera trapping equipment to detect cryptic mammal and squamate species simultaneously.

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