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John E Nelson - One of the best experts on this subject based on the ideXlab platform.
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birth in the northern quoll Dasyurus hallucatus marsupialia dasyuridae
Australian Journal of Zoology, 2003Co-Authors: John E Nelson, R. T. GemmellAbstract:Birth has been observed in a number of marsupial species and, in the studies to date, the newborn have crawled up to or across to the pouch. The method of birth in the quoll, a dasyurid, differs greatly from that observed in other marsupials. Births were recorded at normal speed using hand-held digital video cameras. Birth was heralded by a release of about 1 mL of watery fluid from the urogenital sinus followed by gelatinous material contained in either one or two tubes emanating from the sinus. The newborn, still encased in their placental membranes, were in the gelatinous material within a column. To exit this column, they had to grasp a hair and wriggle about 1 cm across to the pouch. In the pouch the newborn young had to compete for a teat. Although the quolls possessed 8 teats, the number of young in the pouch immediately after birth was 17, 16, 6, 16, 13 and 11 for each of the 6 quolls filmed. While birth has been described previously in another two dasyurids, the observers did not describe birth as reported here for the quoll. Nevertheless the movement of the newborn from the sinus to the pouch is so quick that this could have previously been missed. Filming birth from beneath and from the side allowed for a greater understanding of the birth process. Further studies are required to determine whether this use of a gelatinous material is part of the birth process in all dasyurids.
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Development of the Urinary System of the Marsupial Native Cat Dasyurus hallucatus
Cells Tissues Organs, 1992Co-Authors: John E Nelson, L. Yuemin, R.t. GemrnellAbstract:The development of the mesonephros and metanephros was examined in the marsupial Northern native cat, Dasyurus hallucatus, from birth through to the end of lactation. The mesonephros was present at bi
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Developmental staging in a marsupial Dasyurus hallucatus
Anatomy and Embryology, 1992Co-Authors: John E NelsonAbstract:In a marsupial, Dasyurus hallucatus , pouchyoung of various ages from newborn to 55 days were embedded in wax and serially sectioned. On the basis of the relative development of external and internal characteristics, they were placed in the Carnegie staging system developed by Streeter and elaborated by O'Rahilly and associates. Birth occurred at stage 15, and the end of embryogenesis (stage 23) was reached about day 33. Whereas stage 23 is characterised in all eutherians by the closure of the secondary palate, this occurs before stage 15 in D. hallucatus . Since most other characters of the newborn are at a stage 15 level of development, there has been a relative acceleration of development of the secondary palate (and forelimb) in D. hallucatus that allows it to suckle and breathe at the same time. Between D. hallucatus and eutherians, there is general agreement in the sequence of development and in the relative degree of most structures at each stage. Further marsupials should be examined to see if the minor differences noted are peculiar to D. hallucatus or apply to marsupials generally.
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the development of righting reflexes in the pouch young of the marsupial Dasyurus hallucatus
Developmental Psychobiology, 1992Co-Authors: Sergio M Pellis, Vivein C Pellis, John E NelsonAbstract:The development of righting was studied in the young of Dasyurus hallucatus, a small marsupial from northern Australia. Young were tested from birth to weaning. Righting began at 40 days, when tactile input on the snout triggered rotation to prone. Over the next 15–20 days, asymmetrical tactile input on the body triggered righting movements by the hindlegs (and later by the forelegs). Vestibular righting reflexes developed after these tactile righting reflexes. Furthermore, asymmetrical vestibular righting (i.e., when the young are held laterally in the air) developed before symmetrical vestibular righting (i.e., when held downward by the pelvis or placed supine in water). Vestibular righting triggered by falling supine in the air did not develop until about 80 days. This study further demonstrates that righting behavior does not consist of a single, integrated motor pattern, but a suite of motor patterns having independent control mechanisms and patterns of development. © 1992 Wiley & sons. Inc.
J. P. Darrant - One of the best experts on this subject based on the ideXlab platform.
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diet of the tiger quoll Dasyurus maculatus in south eastern australia
Australian Journal of Zoology, 2007Co-Authors: C. A. Belcher, J. L. Nelson, J. P. DarrantAbstract:Analysis of 338 tiger quoll scats from tableland moist forest in south-eastern New South Wales found that the greater glider was the major prey species occurring in 54.1% of scats and contributing an estimated 51.01% of the biomass consumed by tiger quolls. Medium-sized (0.5–5 kg) mammals were the most important prey group by occurrence (53.9%), frequency (66.0%) and estimated biomass contribution to diet (62.93%). Other medium-sized prey taken by tiger quolls included: long-nosed bandicoot, rabbit, brushtail possum and ringtail possum. Macropods and wombats were also present in the scats and had been presumably taken as carrion. There was no significant difference in the diets of male and female tiger quolls. Tiger quolls were recorded hunting greater gliders in their tree hollows during the day, hunting rabbits in their burrows both during the day and at night and were observed eating road-killed macropods and wombats around dawn and dusk.
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Diet of the tiger quoll (Dasyurus maculatus) in south-eastern Australia
Australian Journal of Zoology, 2007Co-Authors: C. A. Belcher, J. L. Nelson, J. P. DarrantAbstract:Image
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den use by the spotted tailed quoll Dasyurus maculatus in south eastern australia
Australian Mammalogy, 2006Co-Authors: C. A. Belcher, J. P. DarrantAbstract:Den use was investigated by radio-tracking 28 spotted-tailed quolls (Dasyurus maculatus) at three sites in south-eastern Australia. Dens were recorded in rock crevices, caves and boulder tumbles, hollow logs, tree hollows and windrows and in small wombat (Vombatus ursinus) and rabbit (Oryctolagus cuniculus) burrows. Two D. maculatus were recorded using more than 15 dens during this study. Rock dens appeared to be preferred over hollow log dens. D. maculatus denned alone, except when rearing young and possibly during mating. Females used a number of maternal dens while rearing young, some maternal dens were used in consecutive years.
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home range and spatial organization of the marsupial carnivore Dasyurus maculatus maculatus marsupialia dasyuridae in south eastern australia
Journal of Zoology, 2004Co-Authors: C. A. Belcher, J. P. DarrantAbstract:The tiger quoll or spotted-tailed quoll Dasyurus maculatus, a nationally threatened species, is the largest surviving carnivorous marsupial on mainland Australia and the sole surviving member of the genus in south-eastern mainland Australia. Live-trapping and radio-tracking studies at three sites in south-eastern Australia found that tiger quolls were solitary, except when mating, and that male and female tiger quolls occupied very large home ranges, both during and after the breeding season. The mean size of the home range of male tiger quolls (minimum convex polygon (MCP) 1755.4 ha, kernel 3761.7 ha) was significantly larger than the mean size of the home range of females (MCP 495.9 ha, kernel 1113.0 ha). Adult female tiger quolls displayed intrasexual territoriality throughout the year, but they seemed to tolerate the presence of female offspring. Male tiger quolls were not territorial and their home ranges overlapped both with other males and with females throughout the year. Males were recorded regularly moving back and forth between a number of female territories during the breeding season. The spatial organization of the tiger quoll recorded in this study differs markedly from that of the eastern quoll Dasyurus viverrinus and the Tasmanian devil Sarcophilus harrisii, but is similar to that of the western quoll D. geoffroii, northern quoll D. hallucatus and brush-tailed phascogale Phascogale tapoatafa. The spatial organization and home-range size of the tiger quoll dictate that conservation of the species requires management across all land tenures at the landscape level.
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Home range and spatial organization of the marsupial carnivore, Dasyurus maculatus maculatus (Marsupialia: Dasyuridae) in south‐eastern Australia
Journal of Zoology, 2004Co-Authors: C. A. Belcher, J. P. DarrantAbstract:The tiger quoll or spotted-tailed quoll Dasyurus maculatus, a nationally threatened species, is the largest surviving carnivorous marsupial on mainland Australia and the sole surviving member of the genus in south-eastern mainland Australia. Live-trapping and radio-tracking studies at three sites in south-eastern Australia found that tiger quolls were solitary, except when mating, and that male and female tiger quolls occupied very large home ranges, both during and after the breeding season. The mean size of the home range of male tiger quolls (minimum convex polygon (MCP) 1755.4 ha, kernel 3761.7 ha) was significantly larger than the mean size of the home range of females (MCP 495.9 ha, kernel 1113.0 ha). Adult female tiger quolls displayed intrasexual territoriality throughout the year, but they seemed to tolerate the presence of female offspring. Male tiger quolls were not territorial and their home ranges overlapped both with other males and with females throughout the year. Males were recorded regularly moving back and forth between a number of female territories during the breeding season. The spatial organization of the tiger quoll recorded in this study differs markedly from that of the eastern quoll Dasyurus viverrinus and the Tasmanian devil Sarcophilus harrisii, but is similar to that of the western quoll D. geoffroii, northern quoll D. hallucatus and brush-tailed phascogale Phascogale tapoatafa. The spatial organization and home-range size of the tiger quoll dictate that conservation of the species requires management across all land tenures at the landscape level.
Christine Cooper - One of the best experts on this subject based on the ideXlab platform.
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comparative physiology of australian quolls Dasyurus marsupialia
Journal of Comparative Physiology B-biochemical Systemic and Environmental Physiology, 2010Co-Authors: Christine Cooper, Philip C WithersAbstract:Quolls (Dasyurus) are medium-sized carnivorous dasyurid marsupials. Tiger (3,840 g) and eastern quolls (780 g) are mesic zone species, northern quolls (516 g) are tropical zone, and chuditch (1,385 g) were once widespread through the Australian arid zone. We found that standard physiological variables of these quolls are consistent with allometric expectations for marsupials. Nevertheless, inter-specific patterns amongst the quolls are consistent with their different environments. The lower T b of northern quolls (34°C) may provide scope for adaptive hyperthermia in the tropics, and they use torpor for energy/water conservation, whereas the larger mesic species (eastern and tiger quolls) do not appear to. Thermolability varied from little in eastern (0.035°C °C−1) and tiger quolls (0.051°C oC−1) to substantial in northern quolls (0.100°C oC−1) and chuditch (0.146°C oC−1), reflecting body mass and environment. Basal metabolic rate was higher for eastern quolls (0.662 ± 0.033 ml O2 g−1 h−1), presumably reflecting their naturally cool environment. Respiratory ventilation closely matched metabolic demand, except at high ambient temperatures where quolls hyperventilated to facilitate evaporative heat loss; tiger and eastern quolls also salivated. A higher evaporative water loss for eastern quolls (1.43 ± 0.212 mg H2O g−1 h−1) presumably reflects their more mesic distribution. The point of relative water economy was low for tiger (−1.3°C), eastern (−12.5°C) and northern (+3.3) quolls, and highest for the chuditch (+22.6°C). We suggest that these differences in water economy reflect lower expired air temperatures and hence lower respiratory evaporative water loss for the arid-zone chuditch relative to tropical and mesic quolls.
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metabolic ventilatory and hygric physiology of the chuditch Dasyurus geoffroii marsupialia dasyuridae
Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2009Co-Authors: Sylvie Schmidt, Christine Cooper, Philip C WithersAbstract:Abstract The chuditch is a large carnivorous dasyurid marsupial. Historically it had one of the widest geographical distributions of all marsupials, encompassing much of arid Australia, but it is now restricted to the mesic south-west of Western Australia. It is therefore of interest to determine if its physiology better reflects adaptation to its historically arid or present mesic habitat. The basic physiological parameters of the chuditch conform to other marsupials. Body mass of males (1385 g) was > 400% of that predicted by phylogeny and this may be related to its carnivorous diet. Body temperature was 33.9 °C at ambient temperatures ≤ thermoneutrality, with hyperthermia occurring above thermoneutrality. Basal metabolic rate was 0.361 mL O 2 g − 1 h − 1 at an ambient temperature of 31 °C. Metabolic rate increased below the thermoneutral zone by 0.038 mL O 2 g − 1 h − 1 °C − 1 , and above the thermoneutral zone to 0.444 ± 0.059 mL O 2 g − 1 h − 1 at 33.3 °C. Standard evaporative water loss was 0.498 ± 0.071 mg g − 1 h − 1 at an ambient temperature of 26.0 °C, and increased at higher ambient temperatures due to panting and licking. Changes in wet thermal conductance largely reflected changes in evaporative heat loss, and dry thermal conductance increased at high ambient temperature due in part to posture change. Ventilatory parameters were consistent with metabolic demands in and below thermoneutrality, and suggested augmented evaporative heat loss above the thermoneutral zone. Chuditch had a high point of relative water economy of 22.6 °C, indicating favourable water economy at even moderate ambient temperatures, due to its low evaporative water loss rather than high metabolic water production. Chuditch were physiologically more similar to marsupials from arid rather than mesic habitats, better reflecting their historical distribution than their current geographical range.
C. A. Belcher - One of the best experts on this subject based on the ideXlab platform.
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diet of the tiger quoll Dasyurus maculatus in south eastern australia
Australian Journal of Zoology, 2007Co-Authors: C. A. Belcher, J. L. Nelson, J. P. DarrantAbstract:Analysis of 338 tiger quoll scats from tableland moist forest in south-eastern New South Wales found that the greater glider was the major prey species occurring in 54.1% of scats and contributing an estimated 51.01% of the biomass consumed by tiger quolls. Medium-sized (0.5–5 kg) mammals were the most important prey group by occurrence (53.9%), frequency (66.0%) and estimated biomass contribution to diet (62.93%). Other medium-sized prey taken by tiger quolls included: long-nosed bandicoot, rabbit, brushtail possum and ringtail possum. Macropods and wombats were also present in the scats and had been presumably taken as carrion. There was no significant difference in the diets of male and female tiger quolls. Tiger quolls were recorded hunting greater gliders in their tree hollows during the day, hunting rabbits in their burrows both during the day and at night and were observed eating road-killed macropods and wombats around dawn and dusk.
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Diet of the tiger quoll (Dasyurus maculatus) in south-eastern Australia
Australian Journal of Zoology, 2007Co-Authors: C. A. Belcher, J. L. Nelson, J. P. DarrantAbstract:Image
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den use by the spotted tailed quoll Dasyurus maculatus in south eastern australia
Australian Mammalogy, 2006Co-Authors: C. A. Belcher, J. P. DarrantAbstract:Den use was investigated by radio-tracking 28 spotted-tailed quolls (Dasyurus maculatus) at three sites in south-eastern Australia. Dens were recorded in rock crevices, caves and boulder tumbles, hollow logs, tree hollows and windrows and in small wombat (Vombatus ursinus) and rabbit (Oryctolagus cuniculus) burrows. Two D. maculatus were recorded using more than 15 dens during this study. Rock dens appeared to be preferred over hollow log dens. D. maculatus denned alone, except when rearing young and possibly during mating. Females used a number of maternal dens while rearing young, some maternal dens were used in consecutive years.
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home range and spatial organization of the marsupial carnivore Dasyurus maculatus maculatus marsupialia dasyuridae in south eastern australia
Journal of Zoology, 2004Co-Authors: C. A. Belcher, J. P. DarrantAbstract:The tiger quoll or spotted-tailed quoll Dasyurus maculatus, a nationally threatened species, is the largest surviving carnivorous marsupial on mainland Australia and the sole surviving member of the genus in south-eastern mainland Australia. Live-trapping and radio-tracking studies at three sites in south-eastern Australia found that tiger quolls were solitary, except when mating, and that male and female tiger quolls occupied very large home ranges, both during and after the breeding season. The mean size of the home range of male tiger quolls (minimum convex polygon (MCP) 1755.4 ha, kernel 3761.7 ha) was significantly larger than the mean size of the home range of females (MCP 495.9 ha, kernel 1113.0 ha). Adult female tiger quolls displayed intrasexual territoriality throughout the year, but they seemed to tolerate the presence of female offspring. Male tiger quolls were not territorial and their home ranges overlapped both with other males and with females throughout the year. Males were recorded regularly moving back and forth between a number of female territories during the breeding season. The spatial organization of the tiger quoll recorded in this study differs markedly from that of the eastern quoll Dasyurus viverrinus and the Tasmanian devil Sarcophilus harrisii, but is similar to that of the western quoll D. geoffroii, northern quoll D. hallucatus and brush-tailed phascogale Phascogale tapoatafa. The spatial organization and home-range size of the tiger quoll dictate that conservation of the species requires management across all land tenures at the landscape level.
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Home range and spatial organization of the marsupial carnivore, Dasyurus maculatus maculatus (Marsupialia: Dasyuridae) in south‐eastern Australia
Journal of Zoology, 2004Co-Authors: C. A. Belcher, J. P. DarrantAbstract:The tiger quoll or spotted-tailed quoll Dasyurus maculatus, a nationally threatened species, is the largest surviving carnivorous marsupial on mainland Australia and the sole surviving member of the genus in south-eastern mainland Australia. Live-trapping and radio-tracking studies at three sites in south-eastern Australia found that tiger quolls were solitary, except when mating, and that male and female tiger quolls occupied very large home ranges, both during and after the breeding season. The mean size of the home range of male tiger quolls (minimum convex polygon (MCP) 1755.4 ha, kernel 3761.7 ha) was significantly larger than the mean size of the home range of females (MCP 495.9 ha, kernel 1113.0 ha). Adult female tiger quolls displayed intrasexual territoriality throughout the year, but they seemed to tolerate the presence of female offspring. Male tiger quolls were not territorial and their home ranges overlapped both with other males and with females throughout the year. Males were recorded regularly moving back and forth between a number of female territories during the breeding season. The spatial organization of the tiger quoll recorded in this study differs markedly from that of the eastern quoll Dasyurus viverrinus and the Tasmanian devil Sarcophilus harrisii, but is similar to that of the western quoll D. geoffroii, northern quoll D. hallucatus and brush-tailed phascogale Phascogale tapoatafa. The spatial organization and home-range size of the tiger quoll dictate that conservation of the species requires management across all land tenures at the landscape level.
Alistair S Glen - One of the best experts on this subject based on the ideXlab platform.
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why are there so many spotted tailed quolls Dasyurus maculatus in parts of north eastern new south wales
The Australian zoologist, 2011Co-Authors: Alistair S Glen, Chris R DickmanAbstract:This paper explores the question of why the endangered Spotted-tailed Quoll Dasyurus maculatus remains abundant in parts of north-eastern New South Wales, while populations in many other areas have...
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forensic dna confirms intraguild killing of a chuditch Dasyurus geoffroii by a feral cat felis catus
Conservation Genetics, 2010Co-Authors: Alistair S Glen, Oliver Berry, Duncan R Sutherland, S Garretson, T Robinson, P J De ToresAbstract:Because animals killed by predators are often found partially consumed or decomposed, identification of the predator is often unachievable by post mortem examination. Forensic DNA offers an alternative in such situations. Using a novel method to analyse DNA from bite wounds on a freshly-killed chuditch Dasyurus geoffroii, we describe the first confirmed instance in this species of intraguild killing by a feral cat. Unlike post mortem examination, our method of DNA melt curve analysis is highly accurate and requires less time and expense than DNA sequencing.
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interactions between chuditch Dasyurus geoffroii and introduced predators a review
Australian Journal of Zoology, 2009Co-Authors: Alistair S Glen, Duncan R Sutherland, P J De Tores, Keith MorrisAbstract:The chuditch is a carnivorous marsupial that has suffered catastrophic decline since European settlement in Australia. The impacts of introduced foxes and feral cats are thought to have contributed to this decline. Although chuditch populations appear to respond favourably to fox control, ecological theory predicts that other predators, including feral cats, are also likely to increase in abundance when foxes are removed. The flow-on effects of these predicted increases are not known, but are potentially significant for chuditch and for other native fauna. Here, we review the evidence for limiting effects of foxes and feral cats on chuditch populations. We also discuss the likely effects on chuditch populations (direct and indirect) of current fox control practices. Using recent advances in carnivore community ecology, we make testable predictions regarding likely interactions within the predator guild. Experiments should adopt a whole-of-community approach, seeking to clarify the effects of fox control on the entire suite of native and introduced predators, as well as on the abundance and diversity of prey.
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population attributes of the spotted tailed quoll Dasyurus maculatus in north eastern new south wales
Australian Journal of Zoology, 2008Co-Authors: Alistair S GlenAbstract:The spotted-tailed quoll (Dasyurus maculatus) is an endangered marsupial carnivore endemic to eastern Australia. A paucity of information on the dynamics of wild populations has hindered conservation of the species. The population dynamics of spotted-tailed quolls were investigated in an area of unusually high abundance in north-eastern New South Wales, where density is conservatively estimated at 0.3 km-2. Sixty individual quolls were captured on 331 occasions over 22 months. Apparent survival, timing and rate of reproduction, and morphometric data were compared with those of quolls from other areas. Population models were employed to investigate patterns in the behaviour and apparent survival of quolls in the study area. The high abundance of D. maculatus identifies the study area as vital to the conservation of quolls on mainland Australia, and to the future study of the species.
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home range denning behaviour and microhabitat use of the carnivorous marsupial Dasyurus maculatus in eastern australia
Journal of Zoology, 2006Co-Authors: Alistair S Glen, Chris R DickmanAbstract:Radio-tracking of spotted-tailed quolls Dasyurus maculatus (Marsupialia: Dasyuridae) in the forested ranges of north-eastern New South Wales revealed that home ranges were extensive, with males occupying large, overlapping ranges [minimum convex polygon (MCP) up to 757 ha] and females occupying smaller, non-overlapping territories (MCP up to 175 ha). Quolls were partly arboreal, although most activity occurred on the ground or on fallen logs. Hollow logs were most frequently used as dens, but rock crevices, burrows, tree hollows and artificial structures were also used. Individual quolls were located in up to nine different dens and, with the exception of maternal dens, rarely sheltered in the same location on successive days. The large home ranges of the spotted-tailed quoll and the non-overlapping nature of female ranges necessitate very large areas of habitat to support viable populations. Fallen timber, used extensively for shelter and in travelling, may serve to enhance the quality of habitat for the species, and should be retained by forest and wildlife managers.
