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Fritz Geiser - One of the best experts on this subject based on the ideXlab platform.
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The Burramys Project: a conservationist's reach should exceed history's grasp, or what is the fossil record for?
Philosophical transactions of the Royal Society of London. Series B Biological sciences, 2019Co-Authors: Michael Archer, Fritz Geiser, Linda Broome, Hayley Bates, Suzanne J. Hand, Trevor Evans, Bronwyn M. Mcallan, Stephen Jackson, Troy J. Myers, Anna K. GillespieAbstract:The fossil record provides important information about changes in species diversity, distribution, habitat and abundance through time. As we understand more about these changes, it becomes possible to envisage a wider range of options for translocations in a world where sustainability of habitats is under increasing threat. The Critically Endangered alpine/subalpine mountain pygmy-possum, Burramys parvus (Marsupialia, Burramyidae), is threatened by global heating. Using conventional strategies, there would be no viable pathway for stopping this iconic marsupial from becoming extinct. The fossil record, however, has inspired an innovative strategy for saving this species. This lineage has been represented over 25 Myr by a series of species always inhabiting lowland, wet forest palaeocommunities. These fossil deposits have been found in what is now the Tirari Desert, South Australia (24 Ma), savannah woodlands of the Riversleigh World Heritage Area, Queensland (approx. 24-15 Ma) and savannah grasslands of Hamilton, Victoria (approx. 4 Ma). This palaeoecological record has led to the proposal overviewed here to construct a lowland breeding facility with the goal of monitoring the outcome of introducing this possum back into the pre-Quaternary core habitat for the lineage. If this project succeeds, similar approaches could be considered for other climate-change-threatened Australian species such as the southern corroboree frog (Pseudophryne corroboree) and the western swamp tortoise (Pseudemydura umbrina). This article is part of a discussion meeting issue 'The past is a foreign country: how much can the fossil record actually inform conservation?'
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hibernation in free living mountain pygmy possums burramys parvus marsupialia Burramyidae
Australian Journal of Zoology, 1995Co-Authors: Linda Broome, Fritz GeiserAbstract:The long-term pattern of hibernation was studied in free-living mountain pygmy-possums, Burramys parvus, using temperature-sensitive radio-collars. Most males and females began to hibernate in early June within one week of their release. Hibernation was interrupted by spontaneous arousals that were followed by short normothermic periods and re-entry into torpor. The duration of multiday torpor bouts averaged 8 . 0 days (range 3-17 days) and arousal periods averaged 19 . 1 h. Single-day torpor bouts were observed occasionally. The duration of torpor bouts lengthened with the progress of the hibernation season and normothermic periods became shorter. The pattern of hibernation in free-living B. parvus was similar to that of captive individuals maintained under temperature regimes that were similar to those in the wild.
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Hibernation and Daily Torpor in Marsupials - a Review
Australian Journal of Zoology, 1994Co-Authors: Fritz GeiserAbstract:Most heterothermic marsupials appear to display one of the two patterns of torpor that have been described in placental mammals. During shallow, daily torpor body temperature (T(b)) falls for several hours from about 35-degrees-C to values between 11 and 28-degrees-C, depending on the species, and metabolic rates fall to about 10-60% of the basal metabolic rate (BMR). In contrast during deep and prolonged torpor (hibernation), T(b) falls to about 1-5-degrees-C, metabolic rates to about 2-6% of BMR and torpor bouts last for 5-23 days. Shallow, daily torpor has been observed in the opossums (Didelphidae), the carnivorous marsupials (Dasyuridae) and the small possums (Petauridae). Daily torpor may also occur in the numbat (Myrmecobiidae) and the marsupial mole (Notoryctidae). Deep and prolonged torpor (hibernation) has been observed in the pygmy possums (Burramyidae), feathertail glider (Acrobatidae) and Dromiciops australis (Microbiotheriidae). The patterns of torpor in marsupials are paralleled by those of monotremes, placentals and even birds. These similarities in torpor patterns provide some support to the hypothesis that torpor may be plesiomorphic. However, as endothermy and torpor in birds apparently has evolved separately from that in mammals and as torpor occurrence in mammals can change within only a few generations it appears more likely that torpor in endotherms is convergent.
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Hibernation in the eastern pygmy possum, Cercartetus nanus (Marsupialia: Burramyidae)
Australian Journal of Zoology, 1993Co-Authors: Fritz GeiserAbstract:The pattern of torpor was examined in the eastern pygmy possum, Cercartetus nanus (21 g). Animals displayed torpor regularly in the laboratory, and the occurrence of torpor increased with decreasing air temperature (T(a)). At high T(a) (18-degrees-C) animals usually exhibited daily torpor, but torpor bouts of up to 2 days were observed occasionally. The duration of torpor bouts lengthened with a lowering of T(a) and the mean bout duration at T(a) = 5-degrees-C was 17.0 +/- 2.5 days. The minimum metabolic rate (measured as rate of oxygen consumption) of torpid individuals was 0.018 +/- 0.003 mL O2 g-1 h-1, which is less than 2% of the basal metabolic rate. The body temperature (T(b)) Of torpid animals fell to a minimum of 1.3 +/- 0.4-degrees-C. These results clearly demonstrate that Cercartetus nanus is a deep hibernator.
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Prolonged and daily torpor in the feathertail glider, Acrobates pygmaeus (Marsupialia: Acrobatidae)
Journal of Zoology, 1992Co-Authors: Caroline J. Jones, Fritz GeiserAbstract:Deep and prolonged torpor in marsupials is only known from the pygmy possums, family Burramyidae. We investigated the pattern of torpor in the feathertail glider Acrobates pygmaeus (Acrobatidae) to determine whether members of other marsupial families also possess the ability of remaining torpid for several days with body temperatures (Tb) approaching 0°C. At high air temperatures (Ta) of 15 and 20°C, A. pygmaeus usually exhibited daily torpor. Torpor bouts at Ta 12°C usually lasted for about 2˙5 days and at Ta 8°C up to 5˙5 days. The metabolic rate during torpor was reduced to about 1% of that in normothermic, resting individuals. The Tb during torpor was regulated at about 2°C when Ta fell below about 0˙8 °C. Arousal from torpor was rapid and the mean fastest rewarming rate was 0˙88°C/min. While A. pygmaeus exhibited deep and prolonged torpor, its pattern differed somewhat from deep hibernation. Acrobates pygmaeus did not show prehibernation fattening and a subsequent prolonged hibernation period and it appears that prolonged torpor is used only in emergency situations.
Sophie Petit - One of the best experts on this subject based on the ideXlab platform.
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Nest use by western pygmy-possums (Cercartetus concinnus) (Marsupialia : Burramyidae) at Innes National Park, South Australia
Australian Mammalogy, 2011Co-Authors: Damian S. Morrant, Sophie PetitAbstract:We examined the nest use of 15 radio-tracked western pygmy-possums (Cercartetus concinnus) throughout one year for up to nine nights each at Innes National Park, South Australia. At least one pygmy-possum was followed in each of 12 months. Nest type and nest fidelity varied greatly; shallow burrows under debris were the most frequently used. Nest preferences of females with young remain unknown. The ability of C. concinnus to use a diversity of nest types over relatively short periods is likely to be an important survival strategy.
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Diet of the western pygmy possum, Cercartetus concinnus Gould (Marsupialia: Burramyidae), at Innes National Park, South Australia, and evaluation of diet sampling methods
Australian Journal of Zoology, 2007Co-Authors: Angela J. L. Pestell, Sophie PetitAbstract:The diet of a population of western pygmy possums, Cercartetus concinnus Gould (Marsupialia: Burramyidae), at Innes National Park, South Australia, was examined using faecal and fur pollen swab samples in relation to monthly plant phenological data. Eucalyptus pollen was the most abundant in both faeces and in fur swab samples, followed by Melaleuca pollen; plant exudates could not be examined by this study. Moth scales were found in 26% of the scat samples. Faecal samples comprised most plant species identified (15 of 17), but up to 25% of plant species recorded from fur pollen swabs were not recorded from faeces. The relatively high frequencies of plant species represented in fur pollen swabs indicates that this method is valuable for supplementing faecal analysis used to determine plant visitation by nectarivorous animals.
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Genetic structure of the western pygmy possum, Cercartetus concinnus Gould (Marsupialia: Burramyidae) based on mitochondrial DNA
Australian Mammalogy, 2007Co-Authors: Angela J. L. Pestell, Sjb Cooper, Kathleen M. Saint, Sophie PetitAbstract:Cercartetus concinnus Gould (Marsupialia: Burramyidae) has a spatially disjunct distribution, with a broad stretch of saltbush on the Nullarbor Plain forming an apparent barrier between the population: one in southern Western Australia, and another in south-eastern Australia, encompassing South Australia, Victoria, and New South Wales. This disjunct distribution and slight differences in morphology between western and eastern populations have led to conjecture about the taxonomy of this species. This study assessed the taxonomic status of C. concinnus across southern Australia. Analyses using the mitochondrial (mtDNA) ND4 gene showed little phylogeographic structure throughout the wide range of C. concinnus in southern Australia; closely related haplotypes (~0.1% sequence divergence) had a wide distribution from Western Australia to South Australia, suggesting recent genetic connectivity. These data indicate that C. concinnus populations represent a single taxonomic unit (Evolutionarily Significant Unit) throughout the geographic range. Further research is required to assess the impact of recent population fragmentation and whether an erosion of genetic variation in isolated populations has occurred.
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Methods and ethical considerations of pitfall trapping for the western pygmy possum (Cercartetus concinnus Gould) (Marsupialia : Burramyidae), with observations on capture patterns and nest sites
Wildlife Research, 2007Co-Authors: Angela J. L. Pestell, Sophie PetitAbstract:In order to enhance future trapping of the western pygmy possum (Cercartetus concinnus) and minimise the capture of non-target species in the context of animal ethics, we examined the effectiveness of several pitfall-trap capture methods and described capture patterns at Innes National Park, South Australia. For 2606 trap-nights, 78 (2.99 per 100 trap-nights) captures were pygmy possums (70 individuals). They represented 69% of the 113 vertebrates captured, followed by house mice (Mus domesticus) (22%). Nocturnal captures of pygmy possums varied with season (5.21 per 100 trap-nights in spring and summer, and 1.02 in autumn and winter). Males were more commonly captured than females. Half of the pygmy possums used the artificial shelters provided in the traps. We alternated 39-cm-deep and 31-cm-deep pitfall traps along trap lines, with and without drift netting. Pitfall depth did not significantly affect the capture rate of pygmy possums, but house mice were captured significantly more often in deep pitfalls. Use of a drift net did not affect the capture of pygmy possums, but increased mouse captures. These results have significant ethical implications because the use of ‘shallow’ traps and the elimination of the drift net minimised the capture of non-target mice. We recommend reporting trapping details precisely, because a difference of only 8 cm in trap depth can have a significant impact on species selected for capture. Our study also showed that pygmy possums are able to use a range of structures for daily shelter and are not dependent on hollows.
Jamie M Harris - One of the best experts on this subject based on the ideXlab platform.
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Cercartetus lepidus (Diprotodontia: Burramyidae)
Mammalian Species, 2009Co-Authors: Jamie M HarrisAbstract:Cercartetus lepidus (Thomas, 1888) is a burramyid commonly called the little pygmy-possum. It is 1 of 4 species in the genus Cercartetus, which together with Burramys parvus form the marsupial family Burramyidae. This Lilliputian possum has a disjunct distribution, occurring on mainland Australia, Kangaroo Island, and in Tasmania. Mallee and heath communities are occupied in Victoria and South Australia, but in Tasmania it is found mainly in dry and wet sclerophyll forests. It is known from at least 18 fossil sites and the distribution of these reveal a significant contraction in geographic range since the late Pleistocene. Currently, this species is not listed as threatened in any state jurisdictions in Australia, but monitoring is required in order to more accurately define its conservation status. DOI: 10.1644/842.1.
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Cercartetus concinnus (Diprotodontia: Burramyidae)
Mammalian Species, 2009Co-Authors: Jamie M HarrisAbstract:Abstract Cercartetus concinnus (Gould, 1845) is a burramyid commonly called the western pygmy-possum. It is 1 of 4 species in the genus Cercartetus, which together with Burramys parvus form the marsupial family Burramyidae. C. concinnus is endemic to southern mainland Australia. Its habitat is heathlands, shrublands, and dry forests in semiarid zone areas and it feeds on a range of foods, particularly nectar and pollen. This species is notable for short-term hibernation and its role as a pollinator of plants. It is considered secure throughout most of its range except for southwestern New South Wales, where it is classified as endangered.
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Cercartetus nanus (Diprotodontia: Burramyidae)
Mammalian Species, 2008Co-Authors: Jamie M HarrisAbstract:Abstract Cercartetus nanus (Desmarest, 1817) is a burramyid commonly called the eastern pygmy-possum. It is 1 of 4 species in the genus Cercartetus, which together with Burramys parvus form the marsupial family Burramyidae. This species is endemic to southeastern Australia and occupies a range of vegetation types, but Banksia woodland is probably preferred habitat. This species is notable for its longevity, ability to hibernate, and its likely role as an important pollinator of a range of large-flowered plants. This species is of conservation concern in several Australian states, where it is threatened by habitat loss, inappropriate fire regimes, and introduced predators.
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Fossil Occurrences of Cercartetus Nanus (Marsupialia: Burramyidae) in South Australia
Transactions of the Royal Society of South Australia, 2006Co-Authors: Jamie M HarrisAbstract:This study documents the known prehistoric distribution of the eastern pygmy-possum Cercartetus nanus in South Australia. This is based on 10 caves (Bat Cave, Cathedral Cave, Comaum Forest Cave, Ha...
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Palaeodistribution of pygmy-possums in Tasmania.
Papers and Proceedings of the Royal Society of Tasmania, 2006Co-Authors: Jamie M Harris, Jillian GarveyAbstract:This work is a contribution towards documenting the fossil distribution of the pygmy possums Cercartetus lepidus and C. nanus (Marsupialia: Burramyidae) in Tasmania. We provide locality data and bibliographic sources for 15 Quaternary fossil sites important for these species (i.e., Beeton Rockshelter on Badger Island, Cave Bay Cave on Hunter Island, Bone Cave, Derwent River Shelter 7, Kutikina Cave, Mackintosh Cave, Main Drain, March Fly Pot, Newdegate Cave, Nunamira, Ouse River Shelter 7, Peramerpar Meethaner, Pseudocheirus Cave, Warhol, and Warreen Caves on mainland Tasmania). Dates available for these sites span the period 3960 ± 60 to 34,790 ± 510 years ago. We also draw attention to a Late Oligocene fossil locality at Geilston Bay which produced an undescribed Cercartetus-like species. The recorded palaeodistribution of pygmy-possums in Tasmania is widespread, with sites on two offshore islands, and also in the southern, south western, and western areas of mainland Tasmania.
Angela J. L. Pestell - One of the best experts on this subject based on the ideXlab platform.
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Diet of the western pygmy possum, Cercartetus concinnus Gould (Marsupialia: Burramyidae), at Innes National Park, South Australia, and evaluation of diet sampling methods
Australian Journal of Zoology, 2007Co-Authors: Angela J. L. Pestell, Sophie PetitAbstract:The diet of a population of western pygmy possums, Cercartetus concinnus Gould (Marsupialia: Burramyidae), at Innes National Park, South Australia, was examined using faecal and fur pollen swab samples in relation to monthly plant phenological data. Eucalyptus pollen was the most abundant in both faeces and in fur swab samples, followed by Melaleuca pollen; plant exudates could not be examined by this study. Moth scales were found in 26% of the scat samples. Faecal samples comprised most plant species identified (15 of 17), but up to 25% of plant species recorded from fur pollen swabs were not recorded from faeces. The relatively high frequencies of plant species represented in fur pollen swabs indicates that this method is valuable for supplementing faecal analysis used to determine plant visitation by nectarivorous animals.
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Genetic structure of the western pygmy possum, Cercartetus concinnus Gould (Marsupialia: Burramyidae) based on mitochondrial DNA
Australian Mammalogy, 2007Co-Authors: Angela J. L. Pestell, Sjb Cooper, Kathleen M. Saint, Sophie PetitAbstract:Cercartetus concinnus Gould (Marsupialia: Burramyidae) has a spatially disjunct distribution, with a broad stretch of saltbush on the Nullarbor Plain forming an apparent barrier between the population: one in southern Western Australia, and another in south-eastern Australia, encompassing South Australia, Victoria, and New South Wales. This disjunct distribution and slight differences in morphology between western and eastern populations have led to conjecture about the taxonomy of this species. This study assessed the taxonomic status of C. concinnus across southern Australia. Analyses using the mitochondrial (mtDNA) ND4 gene showed little phylogeographic structure throughout the wide range of C. concinnus in southern Australia; closely related haplotypes (~0.1% sequence divergence) had a wide distribution from Western Australia to South Australia, suggesting recent genetic connectivity. These data indicate that C. concinnus populations represent a single taxonomic unit (Evolutionarily Significant Unit) throughout the geographic range. Further research is required to assess the impact of recent population fragmentation and whether an erosion of genetic variation in isolated populations has occurred.
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Methods and ethical considerations of pitfall trapping for the western pygmy possum (Cercartetus concinnus Gould) (Marsupialia : Burramyidae), with observations on capture patterns and nest sites
Wildlife Research, 2007Co-Authors: Angela J. L. Pestell, Sophie PetitAbstract:In order to enhance future trapping of the western pygmy possum (Cercartetus concinnus) and minimise the capture of non-target species in the context of animal ethics, we examined the effectiveness of several pitfall-trap capture methods and described capture patterns at Innes National Park, South Australia. For 2606 trap-nights, 78 (2.99 per 100 trap-nights) captures were pygmy possums (70 individuals). They represented 69% of the 113 vertebrates captured, followed by house mice (Mus domesticus) (22%). Nocturnal captures of pygmy possums varied with season (5.21 per 100 trap-nights in spring and summer, and 1.02 in autumn and winter). Males were more commonly captured than females. Half of the pygmy possums used the artificial shelters provided in the traps. We alternated 39-cm-deep and 31-cm-deep pitfall traps along trap lines, with and without drift netting. Pitfall depth did not significantly affect the capture rate of pygmy possums, but house mice were captured significantly more often in deep pitfalls. Use of a drift net did not affect the capture of pygmy possums, but increased mouse captures. These results have significant ethical implications because the use of ‘shallow’ traps and the elimination of the drift net minimised the capture of non-target mice. We recommend reporting trapping details precisely, because a difference of only 8 cm in trap depth can have a significant impact on species selected for capture. Our study also showed that pygmy possums are able to use a range of structures for daily shelter and are not dependent on hollows.
Linda Broome - One of the best experts on this subject based on the ideXlab platform.
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The Burramys Project: a conservationist's reach should exceed history's grasp, or what is the fossil record for?
Philosophical transactions of the Royal Society of London. Series B Biological sciences, 2019Co-Authors: Michael Archer, Fritz Geiser, Linda Broome, Hayley Bates, Suzanne J. Hand, Trevor Evans, Bronwyn M. Mcallan, Stephen Jackson, Troy J. Myers, Anna K. GillespieAbstract:The fossil record provides important information about changes in species diversity, distribution, habitat and abundance through time. As we understand more about these changes, it becomes possible to envisage a wider range of options for translocations in a world where sustainability of habitats is under increasing threat. The Critically Endangered alpine/subalpine mountain pygmy-possum, Burramys parvus (Marsupialia, Burramyidae), is threatened by global heating. Using conventional strategies, there would be no viable pathway for stopping this iconic marsupial from becoming extinct. The fossil record, however, has inspired an innovative strategy for saving this species. This lineage has been represented over 25 Myr by a series of species always inhabiting lowland, wet forest palaeocommunities. These fossil deposits have been found in what is now the Tirari Desert, South Australia (24 Ma), savannah woodlands of the Riversleigh World Heritage Area, Queensland (approx. 24-15 Ma) and savannah grasslands of Hamilton, Victoria (approx. 4 Ma). This palaeoecological record has led to the proposal overviewed here to construct a lowland breeding facility with the goal of monitoring the outcome of introducing this possum back into the pre-Quaternary core habitat for the lineage. If this project succeeds, similar approaches could be considered for other climate-change-threatened Australian species such as the southern corroboree frog (Pseudophryne corroboree) and the western swamp tortoise (Pseudemydura umbrina). This article is part of a discussion meeting issue 'The past is a foreign country: how much can the fossil record actually inform conservation?'
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hibernation in free living mountain pygmy possums burramys parvus marsupialia Burramyidae
Australian Journal of Zoology, 1995Co-Authors: Linda Broome, Fritz GeiserAbstract:The long-term pattern of hibernation was studied in free-living mountain pygmy-possums, Burramys parvus, using temperature-sensitive radio-collars. Most males and females began to hibernate in early June within one week of their release. Hibernation was interrupted by spontaneous arousals that were followed by short normothermic periods and re-entry into torpor. The duration of multiday torpor bouts averaged 8 . 0 days (range 3-17 days) and arousal periods averaged 19 . 1 h. Single-day torpor bouts were observed occasionally. The duration of torpor bouts lengthened with the progress of the hibernation season and normothermic periods became shorter. The pattern of hibernation in free-living B. parvus was similar to that of captive individuals maintained under temperature regimes that were similar to those in the wild.
