Mass mortalities of grey-headed flying-foxes (Pteropus poliocephalus) from tree collapses

Matthew Mo; Leah Colefax; Bel Manria; Gerardine Hawkins; Joanna Haddock; Racheal Walker; Denise Karkkainen; Alison J. Peel

doi:10.1071/PC24027

RESEARCH ARTICLE (Open Access)

Previous Next Contents Vol 30(6)

Mass mortalities of grey-headed flying-foxes (Pteropus poliocephalus) from tree collapses

Matthew Mo

^A ^* , Leah Colefax ^B , Bel Manria ^C , Gerardine Hawkins ^D , Joanna Haddock ^E , Racheal Walker ^B , Denise Karkkainen ^F and Alison J. Peel ^F

+ Author Affiliations

- Author Affiliations

^A NSW Department of Climate Change, Energy, the Environment and Water, Biodiversity and Conservation Division, Threatened Species and Ecosystems Branch, 4 Parramatta Square, 12 Darcy Street, Parramatta, NSW 2150, Australia.

^B Wildlife Information, Rescue and Education Service, Weddin-Lachlan Branch, PO Box 1612, Young, NSW 2594, Australia.

^C Cowra, NSW 2794, Australia.

^D Wildlife Rescue South Coast, PO Box 666, Nowra, NSW 2541, Australia.

^E NSW Department of Climate Change, Energy, the Environment and Water, Biodiversity and Conservation Division, North West Branch, PO Box 2111, Dubbo, NSW 2830, Australia.

^F Griffith University, Centre for Planetary Health and Food Security, Nathan, Qld 4111, Australia.

^* Correspondence to: matthew.mo@environment.nsw.gov.au

Handling Editor: Mike Calver

Pacific Conservation Biology 30, PC24027 https://doi.org/10.1071/PC24027

Submitted: 4 April 2024 Accepted: 25 October 2024 Published: 12 November 2024

© 2024 The Author(s) (or their employer(s)). Published by CSIRO Publishing. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND)

Abstract

Mortality factors are an important subject of research, especially when mortalities concern threatened taxa. The grey-headed flying-fox (Pteropus poliocephalus) is a vulnerable species endemic to eastern and south-eastern Australia that is known to be susceptible to a spectrum of compounding threats including factors producing simultaneous deaths. We describe two incidents of trees within a flying-fox roost collapsing and causing mass mortalities in individuals roosting in those trees. Each incident resulted in 335 and 57 deaths, as well as 74 and 45 individuals that would have died if not taken into ex-situ care. Total mortality for each incident equated to approximately 15% and 2% of the colony at the time of those incidents. Although flying-foxes are capable of flight, take-off from a roosting position requires an initial freefall, which makes escape from a collapsing tree difficult. Our accounts potentially represent the first reports of tree collapses causing mortality in Australian flying-foxes, which highlight the relevance of tree health in roosts to flying-fox welfare and conservation. This information also builds upon our growing knowledge of factors producing mass mortalities in flying-foxes.

Keywords: Australia, bats, flying-fox roost, mortality factors, New South Wales, Pteropodidae, threatened species, vulnerable species, wildlife mortality.

References

Australian Bureau of Meteorology (2018) Climate data online. Available at http://www.bom.gov.au/climate/data/?ref¼ftr [accessed 20 August 2018]

Australian Bureau of Meteorology (2022) Climate data online. Available at http://www.bom.gov.au/climate/data/?ref¼ftr [accessed 22 November 2022]

Buettner PG, Westcott DA, Maclean J, Brown L, McKeown A, Johnson A, Wilson K, Blair D, Luly J, Skerratt L, Muller R, Speare R (2013) Tick paralysis in spectacled flying-foxes (Pteropus conspicillatus) in North Queensland, Australia: impact of a ground-dwelling ectoparasite finding an arboreal host. PLoS ONE 8, e73078.
| Crossref | Google Scholar | PubMed |

Commonwealth of Australia (2015) Referral guideline for management actions in grey-headed and spectacled flying-fox camps. EPBC Act Policy Statement. Commonwealth of Australia, Canberra.

Department of Agriculture, Water and the Environment (2021) National recovery plan for the grey-headed flying-fox Pteropus poliocephalus. Department of Agriculture, Water and the Environment, Canberra.

Eby P (1995) The biology and management of flying-foxes in NSW. Species Management Report Number 18. NSW National Parks and Wildlife Service, Sydney.

Eby P, Richards G, Collins L, Parry-Jones K (1999) The distribution, abundance and vulnerability to population reduction of a nomadic nectarivore, the grey-headed flying-fox Pteropus poliocephalus in New South Wales, during a period of resource concentration. Australian Zoologist 31, 240-253.
| Crossref | Google Scholar |

Eby P, Roberts B, Pennay M, Welbergen JA (2021) Pteropus poliocephalus. The IUCN Red List of Threatened Species. Available at https://www.iucnredlist.org/species/18751/22085511

Eby P, Peel AJ, Hoegh A, Madden W, Giles JR, Hudson PJ, Plowright RK (2023) Pathogen spillover driven by rapid changes in bat ecology. Nature 613, 340-344.
| Crossref | Google Scholar | PubMed |

Flying-fox Paralysis Syndrome Working Group (2022) Flying-fox paralysis syndrome (FFPS): interim case definition, sample collection and treatment advice. Available at https://wildlifehealthaustralia.com.au/Portals/0/Incidents/FF_Paralysis_Syndrome-case_definition_sampling_treatment.pdf?ver=_fZPMDV2lUuoc96HIYbwzA%3d%3d

Hall L, Richards G (2000) ‘Flying-foxes: fruit and blossom bats of Australia.’ (University of New South Wales Press: Sydney)

Hall LS (2002) Management of flying-fox camps: what have we learnt in the last twenty-five years? In ‘Managing the grey-headed flying-fox as a threatened species in NSW’. (Eds P Eby, D Lunney) pp. 215–224. (Royal Zoological Society of New South Wales: Mosman, NSW) 10.7882/FS.2002.054

IUCN (2024) The IUCN Red List of Threatened Species. Version 2023-1. Available at https://www.iucnredlist.org [accessed 1 February 2024]

Lindhe Norberg UM, Brooke AP, Trewhella WJ (2000) Soaring and non-soaring bats of the family Pteropodidae (flying-foxes, Pteropus spp.): wing morphology and flight performance. Journal of Experimental Biology 203, 651-664.
| Crossref | Google Scholar | PubMed |

Lunn TJ, Eby P, Brooks R, McCallum H, Plowright RK, Kessler MK, Peel AJ (2021) Conventional wisdom on roosting behavior of Australian flying-foxes – a critical review, and evaluation using new data. Ecology and Evolution 11, 13532-13558.
| Crossref | Google Scholar | PubMed |

Mo M, Roache M, Lenson D, Thomson H, Jarvis M, Foster N, Radford A, Oliver L, Oliver DL, Bentley J (2020) Congregations of a threatened species: mitigating impacts from grey-headed flying-fox Pteropus poliocephalus camps on the Batemans Bay community. Australian Zoologist 41, 124-138.
| Crossref | Google Scholar |

Mo M, Roache M, Davies J, Hopper J, Pitty H, Foster N, Guy S, Parry-Jones K, Francis G, Koosmen A, Colefax L, Costello C, Stokes J, Curran S, Smith M, Daly G, Simmons C-M, Hansen R, Prophet D, Judge S, Major F, Hogarth T, McGarry C-A, Pope L, Brend S, Coxon D, Baker K, Kaye K, Collins L, Wallis M, Brown R, Roberts L, Taylor S, Pearson T, Bishop T, Dunne P, Coutts-McClelland K, Oliver L, Dawe C, Welbergen JA (2022a) Estimating flying-fox mortality associated with abandonments of pups and extreme heat events during the austral summer of 2019-20. Pacific Conservation Biology 28, 124-139.
| Crossref | Google Scholar |

Mo M, Minehan M, Hack E, Place V, Welbergen JA (2022b) A report of direct mortality in grey-headed flying-foxes (Pteropus poliocephalus) from the 2019–2020 Australian megafires. Australian Mammalogy 44, 419-422.
| Crossref | Google Scholar |

Mo M, Coutts-McClelland K, Wilson V, Haering R, Oliver L, Bell L, Lunney D (2023a) Managing the grey-headed flying-fox as a threatened species in New South Wales two decades on: threats and conservation issues. Australian Zoologist 42, 897-918.
| Crossref | Google Scholar |

Mo M, Coutts-McClelland K, Wilson V, Haering R, Oliver L, Bell L, Lunney D (2023b) Managing the grey-headed flying-fox as a threatened species in New South Wales two decades on: contentious issues for horticulturalists and communities. Australian Zoologist 42, 871-896.
| Crossref | Google Scholar |

Mo M, Meade J, Roff A, Timmiss LA, Gibson R, Welbergen JA (2024) Impact assessment of the Australian 2019-20 megafires on roost sites of the vulnerable grey-headed flying-fox (Pteropus poliocephalus). Global Ecology and Conservation 50, e02822.
| Crossref | Google Scholar |

NSW Scientific Committee (2001) Grey-headed flying-fox (Pteropus poliocephalus) – vulnerable species listing. NSW Scientific Committee, Sydney.

Office of Environment and Heritage (2018) Flying-fox camp management policy 2015. Office of Environment and Heritage, Sydney.

Ogilvie PW, Ogilvie MB (1964) Observations of a roost of yellow or giant fruit-eating bats, Eidolon helvum. Journal of Mammalogy 45, 309-311.
| Crossref | Google Scholar |

O’Shea TJ, Cryan PM, Hayman DTS, Plowright RK, Streicker DG (2016) Multiple mortality events in bats: a global review. Mammal Review 46, 175-190.
| Crossref | Google Scholar | PubMed |

Parry-Jones KA (2000) Historical declines since the early 1900’s, and current mortality factors and abundance of the grey-headed flying-fox in NSW. In ‘Proceedings of a workshop to assess the status of the grey-headed flying-fox in New South Wales’. (Ed. G Richards) pp. 57–66. (Australasian Bat Society: Canberra)

Ratcliffe FN (1931) The flying-fox (Pteropus) in Australia. Bulletin of the Council for Scientific and Industrial Research 53, 1-80.
| Google Scholar |

Ratnayake HU, Kearney MR, Govekar P, Karoly D, Welbergen JA (2019) Forecasting wildlife die-offs from extreme heat events. Animal Conservation 22, 386-395.
| Crossref | Google Scholar |

Tidemann CR, Nelson JE (2011) Life expectancy, causes of death and movements of the grey-headed flying-fox (Pteropus poliocephalus) inferred from banding. Acta Chiropterologica 13, 419-429.
| Crossref | Google Scholar |

Vincenot CE, Koyama L, Russo D (2015) Near threatened? First report of unsuspected human-driven decline factors in the Ryukyu flying fox (Pteropus dasymallus) in Japan. Mammalian Biology 80, 273-277.
| Crossref | Google Scholar |

Welbergen JA, Klose SM, Markus N, Eby P (2008) Climate change and the effects of temperature extremes on Australian flying-foxes. Proceedings of the Royal Society B: Biological Sciences 275, 419-425.
| Crossref | Google Scholar |

Welbergen JA (2012) The impacts of extreme events on biodiversity – lessons from die-offs in flying-foxes. In ‘Proceedings of the International symposium on the importance of bats as bioindicators’. (Eds C Flaquer, X Puig-Montserrat) pp. 70–75. (Museum of Natural Sciences Edicions: Granollers, Barcelona, Spain)

Welbergen JA, Booth C, Martin J (2014) Killer climate: tens of thousands of flying-foxes dead in a day. Available at https://theconversation.com/killer-climate-tens-of-thousands-of-flying-foxes-dead-in-aday-23227 [accessed 1 February 2024]