The mammal fauna of the Sir Edward Pellew island group, Northern Territory, Australia

refuge and death-trap

John Casimir Zichy-Woinarski, S Ward, T Mahney, J Bradley, K Brennan, A Ziembicki, A Fisher

    Research output: Contribution to journalArticleResearchpeer-review

    Abstract

    Context: Australian islands have provided a major conservation refuge for many native mammals; however, conversely, island populations may also be highly susceptible to the introduction of novel threats. Nearby islands subject to different arrays of threats or different timing of arrival of those threats may provide a natural experiment, offering particular insight into the relative impacts of different threats to Australian mammals more generally.

    Aims: The present study sought to document the native mammal fauna occurring on the main islands of the Sir Edward Pellew group, Northern Territory, and the changes in that fauna over a ?50-year period, and to seek to identify those factors that have contributed to such change.

    Methods: In different combinations, the five main islands (and three smaller islands) were subject to standard wildlife survey methods in 1966-67, 1988, 2003, 2004-05, and 2009-10. Sampling procedures were not identical in all periods; however, a measure of abundance (trap success rate) could be calculated for all sampling. This conventional survey approach was complemented by documentation of ethno-biological knowledge.

    Key results: For many species, these islands held populations of biogeographic or conservation significance. However, there has been a major loss or decline of mammal species from most islands. Extirpation is difficult to prove; however, we consider it most likely that the important regional populations of brush-tailed rabbit-rat (Conilurus penicillatus), northern quoll (Dasyurus hallucatus), northern brush-tailed phascogale (Phascogale pirata), common brushtail possum (Trichosurus vulpecula) and canefield rat (Rattus sordidus) have been lost from these islands, and that northern brown bandicoot (Isoodon macrourus), western chestnut mouse (Pseudomys nanus), pale field-rat (Rattus tunneyi) and long-haired rat (Rattus villosissimus) have been lost from most of the islands on which they formerly occurred. Some speciesisland combinations are known only from the ethno-biological record, and the loss of these populations probably mostly occurred in the period 3050 years ago. Many other declines and losses occurred in the period between the second (1988) and third (2003) survey. The loss of the northern quoll from Vanderlin Island occurred in 2008. No single factor unambiguously accounts for the declines, although the introduction of cats (Felis catus) provides the best fit to the pattern of decline. A notable exception is the extirpation of northern quoll on Vanderlin Island, which is closely linked to the colonisation of that island by cane toads (Rhinella marina).

    Conclusions: The Sir Edward Pellew group of islands have lost much of their formerly high conservation significance for native mammals over the past 50 years, mostly because of introductions of cats, and to a lesser extent, natural colonisation of the islands by cane toads.

    Implications: The present study has provided some insight into the relative impacts of a range of factors that have been considered as possibly implicated in the decline of native mammals on the northern Australian mainland, with most support being offered here for a primary role for predation by feral cats. The study has also demonstrated the need for better quarantining of islands with significant conservation values. The comprehensive natural colonisation of these islands by cane toads offers a further lesson, of most importance to managers of islands in north-western Australia currently just beyond the range of toads.
    Original languageEnglish
    Pages (from-to)307-322
    Number of pages16
    JournalWildlife Research
    Volume38
    Issue number4
    DOIs
    Publication statusPublished - 2011

    Fingerprint

    Northern Territory
    refuge
    mammal
    traps
    fauna
    mammals
    death
    Bufo marinus
    toad
    Rattus
    colonization
    rats
    cats
    Dasyurus
    Trichosurus vulpecula
    survey method
    sampling

    Cite this

    Zichy-Woinarski, John Casimir ; Ward, S ; Mahney, T ; Bradley, J ; Brennan, K ; Ziembicki, A ; Fisher, A. / The mammal fauna of the Sir Edward Pellew island group, Northern Territory, Australia : refuge and death-trap. In: Wildlife Research. 2011 ; Vol. 38, No. 4. pp. 307-322.
    @article{51fc2140eea24edcb215ae97f6251032,
    title = "The mammal fauna of the Sir Edward Pellew island group, Northern Territory, Australia: refuge and death-trap",
    abstract = "Context: Australian islands have provided a major conservation refuge for many native mammals; however, conversely, island populations may also be highly susceptible to the introduction of novel threats. Nearby islands subject to different arrays of threats or different timing of arrival of those threats may provide a natural experiment, offering particular insight into the relative impacts of different threats to Australian mammals more generally. Aims: The present study sought to document the native mammal fauna occurring on the main islands of the Sir Edward Pellew group, Northern Territory, and the changes in that fauna over a ?50-year period, and to seek to identify those factors that have contributed to such change. Methods: In different combinations, the five main islands (and three smaller islands) were subject to standard wildlife survey methods in 1966-67, 1988, 2003, 2004-05, and 2009-10. Sampling procedures were not identical in all periods; however, a measure of abundance (trap success rate) could be calculated for all sampling. This conventional survey approach was complemented by documentation of ethno-biological knowledge. Key results: For many species, these islands held populations of biogeographic or conservation significance. However, there has been a major loss or decline of mammal species from most islands. Extirpation is difficult to prove; however, we consider it most likely that the important regional populations of brush-tailed rabbit-rat (Conilurus penicillatus), northern quoll (Dasyurus hallucatus), northern brush-tailed phascogale (Phascogale pirata), common brushtail possum (Trichosurus vulpecula) and canefield rat (Rattus sordidus) have been lost from these islands, and that northern brown bandicoot (Isoodon macrourus), western chestnut mouse (Pseudomys nanus), pale field-rat (Rattus tunneyi) and long-haired rat (Rattus villosissimus) have been lost from most of the islands on which they formerly occurred. Some speciesisland combinations are known only from the ethno-biological record, and the loss of these populations probably mostly occurred in the period 3050 years ago. Many other declines and losses occurred in the period between the second (1988) and third (2003) survey. The loss of the northern quoll from Vanderlin Island occurred in 2008. No single factor unambiguously accounts for the declines, although the introduction of cats (Felis catus) provides the best fit to the pattern of decline. A notable exception is the extirpation of northern quoll on Vanderlin Island, which is closely linked to the colonisation of that island by cane toads (Rhinella marina). Conclusions: The Sir Edward Pellew group of islands have lost much of their formerly high conservation significance for native mammals over the past 50 years, mostly because of introductions of cats, and to a lesser extent, natural colonisation of the islands by cane toads. Implications: The present study has provided some insight into the relative impacts of a range of factors that have been considered as possibly implicated in the decline of native mammals on the northern Australian mainland, with most support being offered here for a primary role for predation by feral cats. The study has also demonstrated the need for better quarantining of islands with significant conservation values. The comprehensive natural colonisation of these islands by cane toads offers a further lesson, of most importance to managers of islands in north-western Australia currently just beyond the range of toads.",
    keywords = "colonization, ethnobotany, felid, habitat conservation, habitat loss, island biogeography, mammal, native species, population decline, refuge, toad, Australia, Northern Territory, Sir Edward Pellew Group, Anura, Bufo marinus, Conilurus penicillatus, Dasyurus hallucatus, Felis catus, Isoodon macrourus, Mammalia, Mycteroperca fusca, Oryctolagus cuniculus, Phalangeridae, Phascogale, Phascogale tapoatafa, Pirata, Pseudomys nanus, Rattus, Rattus sordidus, Rattus tunneyi, Rattus villosissimus, Trichosurus, Trichosurus vulpecula",
    author = "Zichy-Woinarski, {John Casimir} and S Ward and T Mahney and J Bradley and K Brennan and A Ziembicki and A Fisher",
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    language = "English",
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    pages = "307--322",
    journal = "Wildlife Research",
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    publisher = "CSIRO Publishing",
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    }

    The mammal fauna of the Sir Edward Pellew island group, Northern Territory, Australia : refuge and death-trap. / Zichy-Woinarski, John Casimir; Ward, S; Mahney, T; Bradley, J; Brennan, K; Ziembicki, A; Fisher, A.

    In: Wildlife Research, Vol. 38, No. 4, 2011, p. 307-322.

    Research output: Contribution to journalArticleResearchpeer-review

    TY - JOUR

    T1 - The mammal fauna of the Sir Edward Pellew island group, Northern Territory, Australia

    T2 - refuge and death-trap

    AU - Zichy-Woinarski, John Casimir

    AU - Ward, S

    AU - Mahney, T

    AU - Bradley, J

    AU - Brennan, K

    AU - Ziembicki, A

    AU - Fisher, A

    PY - 2011

    Y1 - 2011

    N2 - Context: Australian islands have provided a major conservation refuge for many native mammals; however, conversely, island populations may also be highly susceptible to the introduction of novel threats. Nearby islands subject to different arrays of threats or different timing of arrival of those threats may provide a natural experiment, offering particular insight into the relative impacts of different threats to Australian mammals more generally. Aims: The present study sought to document the native mammal fauna occurring on the main islands of the Sir Edward Pellew group, Northern Territory, and the changes in that fauna over a ?50-year period, and to seek to identify those factors that have contributed to such change. Methods: In different combinations, the five main islands (and three smaller islands) were subject to standard wildlife survey methods in 1966-67, 1988, 2003, 2004-05, and 2009-10. Sampling procedures were not identical in all periods; however, a measure of abundance (trap success rate) could be calculated for all sampling. This conventional survey approach was complemented by documentation of ethno-biological knowledge. Key results: For many species, these islands held populations of biogeographic or conservation significance. However, there has been a major loss or decline of mammal species from most islands. Extirpation is difficult to prove; however, we consider it most likely that the important regional populations of brush-tailed rabbit-rat (Conilurus penicillatus), northern quoll (Dasyurus hallucatus), northern brush-tailed phascogale (Phascogale pirata), common brushtail possum (Trichosurus vulpecula) and canefield rat (Rattus sordidus) have been lost from these islands, and that northern brown bandicoot (Isoodon macrourus), western chestnut mouse (Pseudomys nanus), pale field-rat (Rattus tunneyi) and long-haired rat (Rattus villosissimus) have been lost from most of the islands on which they formerly occurred. Some speciesisland combinations are known only from the ethno-biological record, and the loss of these populations probably mostly occurred in the period 3050 years ago. Many other declines and losses occurred in the period between the second (1988) and third (2003) survey. The loss of the northern quoll from Vanderlin Island occurred in 2008. No single factor unambiguously accounts for the declines, although the introduction of cats (Felis catus) provides the best fit to the pattern of decline. A notable exception is the extirpation of northern quoll on Vanderlin Island, which is closely linked to the colonisation of that island by cane toads (Rhinella marina). Conclusions: The Sir Edward Pellew group of islands have lost much of their formerly high conservation significance for native mammals over the past 50 years, mostly because of introductions of cats, and to a lesser extent, natural colonisation of the islands by cane toads. Implications: The present study has provided some insight into the relative impacts of a range of factors that have been considered as possibly implicated in the decline of native mammals on the northern Australian mainland, with most support being offered here for a primary role for predation by feral cats. The study has also demonstrated the need for better quarantining of islands with significant conservation values. The comprehensive natural colonisation of these islands by cane toads offers a further lesson, of most importance to managers of islands in north-western Australia currently just beyond the range of toads.

    AB - Context: Australian islands have provided a major conservation refuge for many native mammals; however, conversely, island populations may also be highly susceptible to the introduction of novel threats. Nearby islands subject to different arrays of threats or different timing of arrival of those threats may provide a natural experiment, offering particular insight into the relative impacts of different threats to Australian mammals more generally. Aims: The present study sought to document the native mammal fauna occurring on the main islands of the Sir Edward Pellew group, Northern Territory, and the changes in that fauna over a ?50-year period, and to seek to identify those factors that have contributed to such change. Methods: In different combinations, the five main islands (and three smaller islands) were subject to standard wildlife survey methods in 1966-67, 1988, 2003, 2004-05, and 2009-10. Sampling procedures were not identical in all periods; however, a measure of abundance (trap success rate) could be calculated for all sampling. This conventional survey approach was complemented by documentation of ethno-biological knowledge. Key results: For many species, these islands held populations of biogeographic or conservation significance. However, there has been a major loss or decline of mammal species from most islands. Extirpation is difficult to prove; however, we consider it most likely that the important regional populations of brush-tailed rabbit-rat (Conilurus penicillatus), northern quoll (Dasyurus hallucatus), northern brush-tailed phascogale (Phascogale pirata), common brushtail possum (Trichosurus vulpecula) and canefield rat (Rattus sordidus) have been lost from these islands, and that northern brown bandicoot (Isoodon macrourus), western chestnut mouse (Pseudomys nanus), pale field-rat (Rattus tunneyi) and long-haired rat (Rattus villosissimus) have been lost from most of the islands on which they formerly occurred. Some speciesisland combinations are known only from the ethno-biological record, and the loss of these populations probably mostly occurred in the period 3050 years ago. Many other declines and losses occurred in the period between the second (1988) and third (2003) survey. The loss of the northern quoll from Vanderlin Island occurred in 2008. No single factor unambiguously accounts for the declines, although the introduction of cats (Felis catus) provides the best fit to the pattern of decline. A notable exception is the extirpation of northern quoll on Vanderlin Island, which is closely linked to the colonisation of that island by cane toads (Rhinella marina). Conclusions: The Sir Edward Pellew group of islands have lost much of their formerly high conservation significance for native mammals over the past 50 years, mostly because of introductions of cats, and to a lesser extent, natural colonisation of the islands by cane toads. Implications: The present study has provided some insight into the relative impacts of a range of factors that have been considered as possibly implicated in the decline of native mammals on the northern Australian mainland, with most support being offered here for a primary role for predation by feral cats. The study has also demonstrated the need for better quarantining of islands with significant conservation values. The comprehensive natural colonisation of these islands by cane toads offers a further lesson, of most importance to managers of islands in north-western Australia currently just beyond the range of toads.

    KW - colonization

    KW - ethnobotany

    KW - felid

    KW - habitat conservation

    KW - habitat loss

    KW - island biogeography

    KW - mammal

    KW - native species

    KW - population decline

    KW - refuge

    KW - toad

    KW - Australia

    KW - Northern Territory

    KW - Sir Edward Pellew Group

    KW - Anura

    KW - Bufo marinus

    KW - Conilurus penicillatus

    KW - Dasyurus hallucatus

    KW - Felis catus

    KW - Isoodon macrourus

    KW - Mammalia

    KW - Mycteroperca fusca

    KW - Oryctolagus cuniculus

    KW - Phalangeridae

    KW - Phascogale

    KW - Phascogale tapoatafa

    KW - Pirata

    KW - Pseudomys nanus

    KW - Rattus

    KW - Rattus sordidus

    KW - Rattus tunneyi

    KW - Rattus villosissimus

    KW - Trichosurus

    KW - Trichosurus vulpecula

    U2 - 10.1071/WR10184

    DO - 10.1071/WR10184

    M3 - Article

    VL - 38

    SP - 307

    EP - 322

    JO - Wildlife Research

    JF - Wildlife Research

    SN - 1035-3712

    IS - 4

    ER -