Diet of the mulgara, Dasycercus cristicauda (Marsupialia : Dasyuridae), in the Simpson Desert, central Australia

1998 ◽  
Vol 25 (3) ◽  
pp. 233 ◽  
Author(s):  
Xiaolin Chen ◽  
Chris R. Dickman ◽  
Michael B. Thompson
Keyword(s):  
Seasonal Reproduction ◽  
Prey Selectivity ◽  
Percentage Frequency ◽  
Invertebrate Prey ◽  
European Settlement ◽  
Dietary Flexibility ◽  
Large Numbers ◽  
Central Australia ◽  
Simpson Desert ◽  
Prey Items

The diet of the mulgara, Dasycercus cristicauda, from the Simpson Desert in Queensland, was analysed using scats collected between 1990 and 1995. Insects, arachnids and rodents were the main classes of prey of D. cristicauda, but reptiles, centipedes and small marsupials were also consumed. Insects represented 92% by percentage frequency of occurrence in scats, while rodents represented 33% by percentage frequency. Invertebrate prey ≥6 mm in length and vertebrate prey occurred frequently in scats, but small prey ( 1–5 mm), when present, occurred in large numbers. D. cristicauda ate more individual prey items in spring and winter than in autumn, and more large-sized prey in spring than in autumn. In autumn, D. cristicauda consumed mostly insects (100% by frequency) and few rodents (8%), but in winter and spring, switched to rodents (38% and 47% respectively) and insects (88% and 93% respectively). Seasonal shifts in diet may reflect changes in the availability of different groups of prey, or changes in prey selectivity by D. cristicauda in response to costs imposed by seasonal reproduction. The dietary flexibility of D. cristicauda may allow individuals to occupy stable ranges, and has perhaps also promoted the persistence of the species in arid areas that have been subjected to changes in land use since European settlement.

Habitat use and behaviour of cattle in a heterogeneous desert environment in central Australia

2012 ◽  
Vol 34 (3) ◽  
pp. 319 ◽  
Author(s):  
Anke S. K. Frank ◽  
Chris R. Dickman ◽  
Glenda M. Wardle
Keyword(s):  
Habitat Use ◽  
Arid Environments ◽  
Desert Environment ◽  
Point Location ◽  
Dune System ◽  
Grazing Impacts ◽  
Water Point ◽  
Resource Poor ◽  
Central Australia ◽  
Simpson Desert

The activities of livestock in arid environments typically centre on watering points, with grazing impacts often predicted to decrease uniformly, as radial piospheres, with distance from water. In patchy desert environments, however, the spatial distribution of grazing impacts is more difficult to predict. In this study sightings and dung transects are used to identify preferred cattle habitats in the heterogeneous dune system of the Simpson Desert, central Australia. The importance of watering points as foci for cattle activity was confirmed and it was shown that patchily distributed gidgee woodland, which comprises only 16% of the desert environment, is the most heavily used habitat for cattle away from water and provides critical forage and shade resources. By contrast, dune swales and sides, which are dominated by shade- and forage-deficient spinifex grassland and comprise >70% of the available habitat, were less utilised. These results suggest that habitat use by cattle is influenced jointly by water point location and by the dispersion of woodland patches in a resource-poor matrix. The findings were used to build a modified conceptual model of cattle habitat use which was compared with an original piosphere model, and the consequences for wildlife in environments where the model applies are discussed.

Challenging the concept of Aboriginal mosaic fire practices in the Lake Eyre Basin

2015 ◽  
Vol 37 (6) ◽  
pp. 623 ◽  
Author(s):  
R. G. Kimber ◽  
M. H. Friedel
Keyword(s):  
Aboriginal People ◽  
Fire Hazard ◽  
Management Tool ◽  
Desert Region ◽  
Fuel Loads ◽  
European Settlement ◽  
Natural Landscapes ◽  
Large Fires ◽  
Feral Animals ◽  
Simpson Desert

Mosaic burning is the deliberate creation of a mosaic of patches representing different fire histories. It is often recommended for management of Australia’s natural landscapes, on the assumption that it enhances biodiversity and reduces fire hazard through increased spatial and temporal diversity of fuel loads and species composition. It is also suggested that such fire practices were used throughout Australia by traditionally living Aboriginal people. Although the creation of a patchwork of different fire histories may be an effective management tool in modern land management, the evidence for universal mosaic burning before European settlement deserves scrutiny. The records of explorers, early settlers and anthropologists relating to a large portion of the Lake Eyre Basin, particularly the Channel country and the Simpson Desert region, were examined. It is concluded that extensive gaps in the records of smokes and large fires are important and meaningful, and do not represent a failure to record fires. The case for universal mosaic burning in the region is not supported by the evidence although mosaic burning did occur in specific circumstances. Fire practices were shaped by complex and interacting factors including the vegetation and terrain type, for example the occurrence of spinifex-dominated sandhills or stony deserts; seasonal conditions and the presence or not of adequate fuel loads; how readily Aboriginal people could access country and their reasons for using or not using fire; the stocking of the pastoral country and spread of feral animals; and government policies about fire.

ORGANIC PETROLOGY AND GEOCHEMISTRY OF SOURCE ROCKS IN THE PEDIRKA-SIMPSON BASINS CENTRAL AUSTRALIA

1981 ◽  
Vol 21 (1) ◽  
pp. 187
Author(s):  
M. Smyth ◽  
J. D. Saxby
Keyword(s):  
Petroleum Hydrocarbons ◽  
Vitrinite Reflectance ◽  
Geothermal Gradient ◽  
Source Rocks ◽  
Volatile Hydrocarbons ◽  
Organic Petrology ◽  
Reflected Light ◽  
Petrology And Geochemistry ◽  
Central Australia ◽  
Simpson Desert

Sediments from the Permian Pedirka Basin and the overlying Triassic Simpson Desert Basin have been studied to determine their potentials as source rocks for hydrocarbons. Principal techniques used are reflected light microscopy, including vitrinite reflectance, solvent extraction and kerogen isolation.Dispersed organic matter (DOM) occurs through the Permian and Triassic sequences, and is most abundant near the top of the Triassic, constituting up to 2 per cent of the sediments by volume. Of this DOM, 30 to 50 per cent is vitrinite plus exinite. The Permian and Triassic coals have vitrinite reflectivities of up to 0.9 per cent. The geothermal gradient in the vicinity of Poolowanna 1 is probably sufficient to cause the cutinite within the Triassic sediments to break down into petroleum hydrocarbons. In the case of the Poolowanna Jurassic oil show, migration up faults and accumulation in high-temperature reservoirs have been accompanied by the loss of volatile hydrocarbons.

Seasonal changes in the diet, food availability and food preference of the greater bilby (Macrotis lagotis) in south-western Queensland

2001 ◽  
Vol 28 (2) ◽  
pp. 121 ◽  
Author(s):  
Lesley A. Gibson
Keyword(s):  
Food Availability ◽  
Seasonal Changes ◽  
Arid Zone ◽  
Feeding Strategy ◽  
Frequency Of Occurrence ◽  
Plant Component ◽  
Faecal Pellets ◽  
Food Items ◽  
Invertebrate Prey ◽  
Prey Items

Diet and food availability of the greater bilby (Macrotis lagotis), was examined at two sites and over two summer and two winter seasons in Astrebla Downs National Park in south-western Queensland. The presence of both invertebrate and plant material in almost all faecal pellets (99.6% and 98.5%, respectively) indicated that bilbies in south-western Queensland are omnivorous. The plant component of the bilby diet consisted predominantly of Dactyloctenium radulans seeds (frequency of occurrence: 94.4%). The major invertebrate prey items were Isop-tera (termites, 73.1%) and Formicidae (ants, 77.6%). The frequency of occurrence of invertebrates in faecal pellets was higher during summer than winter, but the frequency of occurrence of plants was relatively constant regardless of season. Within the invertebrate categories, Isoptera and Acrididae (grasshoppers) displayed the greatest seasonal difference, with a significantly higher proportion of both categories in the diet during summer than winter at both study sites. The availability of invertebrate prey items also varied with season, and for most taxa, frequency of oc-currence was significantly higher in summer than winter. In contrast, the frequency of occurrence of seeds and bulbs (Cyperus bulbosus) varied only slightly with season. Seasonal changes in food availability were reflected by variation in dietary composition; however, relative proportions of some dietary items differed from their proportional availability. Therefore, bilbies were considered to be qualitatively opportunistic; selecting more invertebrates when their apparent availability increased, but continually exploiting the available seeds and bulbs. Additionally, although bilbies appeared to have some preferences for particular food items, several food items were selected almost randomly, and therefore bilbies were also considered to be dietary generalists. Such an opportunistic feeding strategy is advantageous to an arid-zone species as it permits the continuous exploitation of food resources that are unpredictable in their availability both spatially and temporally.

scholarly journals Gluttonous predators: how to estimate prey size when there are too many prey

2008 ◽  
Vol 68 (2) ◽  
pp. 315-320 ◽  
Author(s):  
MS. Araújo ◽  
A. Pinheiro ◽  
SF. Reis
Keyword(s):  
Prey Size ◽  
Feeding Habits ◽  
Stomach Contents ◽  
Sampling Effort ◽  
High Intake ◽  
Precision Error ◽  
Bootstrap Procedure ◽  
Future Studies ◽  
Large Numbers ◽  
Prey Items

Prey size is an important factor in food consumption. In studies of feeding ecology, prey items are usually measured individually using calipers or ocular micrometers. Among amphibians and reptiles, there are species that feed on large numbers of small prey items (e.g. ants, termites). This high intake makes it difficult to estimate prey size consumed by these animals. We addressed this problem by developing and evaluating a procedure for subsampling the stomach contents of such predators in order to estimate prey size. Specifically, we developed a protocol based on a bootstrap procedure to obtain a subsample with a precision error of at the most 5%, with a confidence level of at least 95%. This guideline should reduce the sampling effort and facilitate future studies on the feeding habits of amphibians and reptiles, and also provide a means of obtaining precise estimates of prey size.

Sign in / Sign up

Export Citation Format

Share Document