Register      Login
Australian Mammalogy Australian Mammalogy Society
Journal of the Australian Mammal Society
Shopping Cart: ( empty )
You are here: Home > Journals > AM > AM23033
RESEARCH ARTICLE
Contents Vol 46(1)

Should the Christmas Island shrew (Crocidura trichura) be considered extinct?

John C. Z. Woinarski https://orcid.org/0000-0002-1712-9500 A * , B. Tiernan B and S. M. Legge https://orcid.org/0000-0001-6968-2781 A C
+ Author Affiliations
- Author Affiliations

A Research Institute of Environment and Livelihoods, Charles Darwin University, Casuarina, NT, 0810, Australia.

B Christmas Island National Park, Christmas Island, 6798, Australia.

C Fenner School of Society and the Environment, The Australian National University, Acton, Canberra, ACT, 0200, Australia.

* Correspondence to: John.Woinarski@cdu.edu.au

Handling Editor: Mark Eldridge

Australian Mammalogy 46, AM23033 https://doi.org/10.1071/AM23033
Submitted: 26 June 2023  Accepted: 15 August 2023  Published: 5 September 2023

© 2024 The Author(s) (or their employer(s)). Published by CSIRO Publishing on behalf of the Australian Mammal Society.

Abstract

The Christmas Island shrew (Crocidura trichura), endemic to Christmas Island in the Indian Ocean, was abundant at the time of the island’s settlement in the 1890s. However, since 1900, it has been reported only four times (twice in 1958, 1984 and 1985). It is currently considered Critically Endangered under Australian law. Using a recently developed IUCN protocol (the ‘Records and Surveys Model’), based on compilation and assessments of targeted and general sampling effort and detectability, we estimated that there is a 96.3% likelihood that the species is now extinct. However, although many general survey methods (including inspection of cat gut samples, ink cards, audio-recording, pitfall traps, spotlighting and camera traps) have been employed on Christmas Island, most recent sampling has not been targeted specifically to detect this species. Furthermore, there is considerable uncertainty about its likely detectability with different sampling techniques and hence much uncertainty about the estimate of likelihood of extinction. e-DNA sampling, use of detector dogs and refinements in audio-recording may help increase the likelihood of detection, if present. Most current conservation management actions, undertaken for other threatened species on Christmas Island, would provide benefit to the Christmas Island shrew, if it is extant.

Keywords: Christmas Island shrew, conservation status, Crocidura trichura, extinction, lost species, sampling effort, Soricidae, survey.

References

Akçakaya, H. R., Keith, D. A., Burgman, M., Butchart, S. H. M., Hoffmann, M., Regan, H. M., Harrison, I., and Boakes, E. (2017). Inferring extinctions III: A cost-benefit framework for listing extinct species. Biological Conservation 214, 336-342.
| Crossref | Google Scholar |

Algar, D., and Brazell, R. I. (2005). ‘Efficacy of a baiting technique to control feral cats on Christmas Island’. Report to Christmas Island Phosphates. (Perth.) (Department of Conservation and Land Management)

AMTC (2022). The Australasian Mammal Taxonomy Consortium Australian Mammal Species List. Version 2.0. Available at https://australianmammals.org.au/publications/amtc-species-list

Andrews, C. W. (1900a). Mammalia. In ‘A monograph of Christmas Island (Indian Ocean) – physical features and geology, with descriptions of the fauna and flora by numerous contributors’. (Ed. C. W. Andrews.) pp. 22–37. (British Museum Trustees: London)

Andrews, C. W. (1900b). ‘A monograph of Christmas Island (Indian Ocean) – physical features and geology, with descriptions of the fauna and flora by numerous contributors.’ (British Museum Trustees: London)

Andrews, C. W. (1909). On the fauna of Christmas Island. Proceedings of the Zoological Society of London 79, 101-103.
| Google Scholar |

Baker, A. M., and Gynther, I. C. (Eds) (2023). ‘Strahan’s Mammals of Australia’, 4th edn. (Reed New Holland Publishers: Wahroonga, NSW)

Butchart, S. H. M., Lowe, S., Martin, R. W., Symes, A., Westrip, J. R. S., and Wheatley, H. (2018). Which bird species have gone extinct? A novel quantitative classification approach. Biological Conservation 227, 9-18.
| Crossref | Google Scholar |

Chasen, F. N. (1933). Notes on the fauna of Christmas Island, Indian Ocean. Introduction. Bulletin of the Raffles Museum 8, 51-54.
| Google Scholar |

Collar, N. J. (1998). Extinction by assumption; or, the Romeo Error on Cebu. Oryx 32, 239-244.
| Crossref | Google Scholar |

Corbett, L., Crome, F., and Richards, G. (2003). ‘Fauna survey of mine lease applications & National Park reference areas, Christmas Island, August 2002.’ (EWL Sciences Pty Ltd for Phosphate Resources Limited: Darwin)

Eldridge, M. D. B., Meek, P. D., and Johnson, R. N. (2014). Taxonomic uncertainty and the loss of biodiversity on Christmas Island, Indian Ocean. Conservation Biology 28, 572-579.
| Crossref | Google Scholar |

Emery, J.-P., Mitchell, N. J., Cogger, H., Agius, J., Andrew, P., Arnall, S., Detto, T., Driscoll, D. A., Flakus, S., Green, P., Harlow, P., McFadden, M., Pink, C., Retallick, K., Rose, K., Sleeth, M., Tiernan, B., Valentine, L. E., and Woinarski, J. Z. (2021). The lost lizards of Christmas Island: A retrospective assessment of factors driving the collapse of a native reptile community. Conservation Science and Practice 3, e358.
| Crossref | Google Scholar |

Garnett, S. T., Hayward-Brown, B. K., Kopf, R. K., Woinarski, J. C. Z., Cameron, K. A., Chapple, D. G., Copley, P., Fisher, A., Gillespie, G., Latch, P., Legge, S., Lintermans, M., Moorrees, A., Page, M., Renwick, J., Birrell, J., Kelly, D., and Geyle, H. M. (2022). Australia’s most imperilled vertebrates. Biological Conservation 270, 109561.
| Crossref | Google Scholar |

Gibson-Hill, C. A. (1947a). Contributions to the natural history of Christmas Island, in the Indian Ocean. Bulletin of the Raffles Museum 18, 6-7.
| Google Scholar |

Gibson-Hill, C. A. (1947b). A note on the mammals of Christmas Island. Bulletin of the Raffles Museum 18, 166-167.
| Google Scholar |

Green, P. (2014). Mammal extinction by introduced infectious disease on Christmas Island (Indian Ocean): the historical context. Australian Zoologist 37, 1-14.
| Crossref | Google Scholar |

Green, P. T., O’Dowd, D. J., and Lake, P. S. (1997). Control of seedling recruitment by land crabs in rain forest on a remote oceanic island. Ecology 78, 2474-2486.
| Crossref | Google Scholar |

Hill, R. (2004). ‘National Recovery Plan for the Christmas Island Goshawk Accipiter fasciatus natalis.’ (Commonwealth of Australia: Canberra)

Hill, F. A. R., and Lill, A. (1998). Diet and roost site characteristics of the Christmas Island Hawk-Owl Ninox natalis. Emu - Austral Ornithology 98, 227-233.
| Crossref | Google Scholar |

IUCN Standards and Petitions Subcommittee (2022). ‘Guidelines for Using the IUCN Red List Categories and Criteria. Version 15.’ (Gland, Switzerland.) (International Union for the Conservation of Nature)

James, D. J. (2004). ‘Christmas Island biodiversity monitoring programme: third quarterly report for the period April to June 2004.’ (Parks Australia North, Christmas Island)

James, D. (2005). ‘Christmas Island Biodiversity Monitoring Programme: quarterly report for the period October to December 2004’. Report to the Department of Finance and Administration. (Parks Australia: Christmas Island)

James, D. J. (2006). ‘Christmas Island biodiversity monitoring program: progress report for the period April to December 2005.’ (Parks Australia North: Christmas Island)

James, D. (2007). ‘Christmas Island Biodiversity Monitoring Programme: summary report, December 2003 to April 2006.’ (Department of Environment and Heritage: Canberra)

James, D. J., and Retallick, K. (2007). ‘Christmas Island biodiversity monitoring programme: research into the conservation status and threats of the Christmas Island pipistrelle (Pipistrellus murrayi), 2004-2006.’ (Department of Environment Water Heritage and the Arts: Canberra)

James, D. J., Green, P. T., Humphreys, W. F., and Woinarski, J. C. Z. (2019). Endemic species of Christmas Island, Indian Ocean. Records of the Western Australian Museum 34, 55-114.
| Crossref | Google Scholar |

Keith, D. A., Butchart, S. H. M., Regan, H. M., Harrison, I., Akçakaya, H. R., Solow, A. R., and Burgman, M. A. (2017). Inferring extinctions I: a structured method using information on threats. Biological Conservation 214, 320-327.
| Crossref | Google Scholar |

Lister, J. J. (1888). On the Natural History of Christmas Island in the Indian Ocean. Proceedings of the Zoological Society, London 56, 512-531.
| Crossref | Google Scholar |

Low, T., and Booth, C. (2023). ‘GONE: Australian animals extinct since the 1960s.’ (Invasive Species Council Inc.: Katoomba)

Lumsden, L., and Cherry, K. (1997). ‘Report on a preliminary investigation of the Christmas Island pipistrelle, Pipistrellus murrayi, in June-July 1994.’ (Arthur Rylah Institute for Environmental Research: Melbourne)

Lumsden, L., Silins, J., and Schulz, M. (1999). ‘Population dynamics and ecology of the Christmas Island Pipistrelle Pipistrellus murrayi on Christmas Island.’ (Arthur Rylah Institute for Environmental Research: Melbourne)

Lumsden, L., Schulz, M., Ashton, R., and Middleton, D. (2007). ‘Investigation of the threats to the Christmas Island Pipistrelle.’ (Arthur Rylah Institute for Environmental Research: Melbourne)

Maple, D. J., Barr, R., and Smith, M. J. (2012). A new record of the Christmas Island Blind Snake, Ramphotyphlops exocoeti (Reptilia: Squamata: Typhlopidae). Records of the Western Australian Museum 27, 156-160.
| Crossref | Google Scholar |

Meek, P. D. (2000). The decline and current status of the Christmas Island Shrew Crocidura attentuata trichura on Christmas Island, Indian Ocean. Australian Mammalogy 22, 43-49.
| Crossref | Google Scholar |

Rhinehart, T. A., Chronister, L. M., Devlin, T., and Kitzes, J. (2020). Acoustic localization of terrestrial wildlife: Current practices and future opportunities. Ecology and Evolution 10, 6794-6818.
| Crossref | Google Scholar |

Rumpff, H. (1992). ‘Distribution, population structure and ecological behaviour of the introduced South-East Asian Wolf Snake Lycodon aulicus capucinus on Christmas Island, Indian Ocean.’ (Australian National Parks and Wildlife Service: Christmas Island.)

Schulz, M. (2004). ‘National Recovery Plan for the Christmas Island Shrew Crocidura attenuata trichura.’ (Department of the Environment and Heritage: Canberra)

Selwood, K. E., Wintle, B. A., and Kujala, H. (2019). Collaborative conservation planning: Quantifying the contribution of expert engagement to identify spatial conservation priorities. Conservation Letters 12, e12673.
| Crossref | Google Scholar |

Shonfield, J., and Bayne, E. M. (2017). Autonomous recording units in avian ecological research: current use and future applications. Avian Conservation & Ecology 12, 14.
| Crossref | Google Scholar |

Tennant, E. N., Cypher, B. L., Saslaw, L. R., Westall, T. L., Mohay, J. L., Kelly, E. C., and Van Horn Job, C. L. (2020). Evaluation of noninvasive survey methods for detecting endangered shrews. Wildlife Society Bulletin 44, 610-616.
| Crossref | Google Scholar |

Thomas, O. (1887). Report on a zoological collection made by the officers of H.M.S. “Flying Fish” at Christmas Island, Indian Ocean. I. Mammalia. Proceedings of the Zoological Society London 1887, 511-514.
| Google Scholar |

Thomas, O. (1888). On the mammals of Christmas Island. Proceedings of the Zoological Society London 56, 532-534.
| Crossref | Google Scholar |

Thompson, C. J., Koshkina, V., Burgman, M. A., Butchart, S. H. M., and Stone, L. (2017). Inferring extinctions II: a practical, iterative model based on records and surveys. Biological Conservation 214, 328-335.
| Crossref | Google Scholar |

Threatened Species Scientific Committee (2018). Conservation Advice - Crocidura trichura Christmas Island Shrew, Canberra. Available at http://www.environment.gov.au/biodiversity/threatened/species/pubs/87888-conservation-advice-05052016.pdf

Tidemann, C. R. (1985). ‘A study of the status, habitat requirements and management of the two species of bats on Christmas Island (Indian Ocean).’ (Canberra.) (Australian National University)

Tidemann, C. R. (1989). ‘Survey of the terrestrial mammals on Christmas Island (Indian Ocean)’. Report to Australian National Parks and Wildlife Service. (Canberra.) (Australian National University.)

Wharton, W. J. L. (1887). Christmas Island. Nature 37, 203-204.
| Crossref | Google Scholar |

Woinarski, J. (2018). ‘A bat’s end: the Christmas Island pipistrelle and extinction in Australia.’ (CSIRO Publishing: Melbourne.)

Woinarski, J. C. Z., Burbidge, A. A., and Harrison, P. L. (2014). ‘The Action Plan for Australian Mammals 2012.’ (CSIRO Publishing: Melbourne)

Woinarski, J., Burbidge, A. A., and Lumsden, L. (2016). Crocidura trichura. Available at https://www.iucnredlist.org/species/136379/22304640

Woinarski, J. C. Z., Braby, M. F., Burbidge, A. A., Coates, D., Garnett, S. T., Fensham, R. J., Legge, S. M., McKenzie, N. L., Silcock, J. L., and Murphy, B. P. (2019). Reading the black book: the number, timing, distribution and causes of listed extinctions in Australia. Biological Conservation 239, 108261.
| Crossref | Google Scholar |

Wyatt, K. B., Campos, P. F., Gilbert, M. T. P., Kolokotronis, S.-O., Hynes, W. H., DeSalle, R., Daszak, P., MacPhee, R. D. E., and Greenwood, A. D. (2008). Historical mammal extinction on Christmas Island (Indian Ocean) correlates with introduced infectious disease. PLoS One 3, e3602.
| Crossref | Google Scholar |

Yonezawa, S., Ushio, M., Yamanaka, H., Miya, M., Takayanagi, A., and Isagi, Y. (2020). Environmental DNA metabarcoding reveals the presence of a small, quick-moving, nocturnal water shrew in a forest stream. Conservation Genetics 21, 1079-1084.
| Crossref | Google Scholar |

Zsebők, S., Czabán, D., Farkas, J., Siemers, B. M., and von Merten, S. (2015). Acoustic species identification of shrews: twittering calls for monitoring. Ecological Informatics 27, 1-10.
| Crossref | Google Scholar |