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Pacific Conservation Biology Pacific Conservation Biology Society
A journal dedicated to conservation and wildlife management in the Pacific region.
RESEARCH ARTICLE (Open Access)

Islands in the sky – could complex topography help us rewild beyond the fence?

Rob Brewster https://orcid.org/0000-0001-5068-8614 A * , Tom Jameson https://orcid.org/0009-0006-4041-6037 A B , Francesca Roncolato https://orcid.org/0009-0009-9663-2638 A , Mathew S. Crowther https://orcid.org/0000-0001-8968-1161 C , Patrick B. Finnerty https://orcid.org/0000-0001-5762-6272 C * and Thomas M. Newsome https://orcid.org/0000-0003-3457-3256 C
+ Author Affiliations
- Author Affiliations

A WWF Australia, PO Box 528, Sydney, NSW 2001, Australia.

B Department of Zoology and University Museum of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.

C School of Life and Environmental Sciences, Faculty of Science, University of Sydney, Sydney, NSW, Australia.


Handling Editor: Mike Calver

Pacific Conservation Biology 30, PC24022 https://doi.org/10.1071/PC24022
Submitted: 25 March 2024  Accepted: 2 August 2024  Published: 15 August 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

Context

The protection of threatened species in fenced safe havens has become a vital component of conservation management in Australia. However, despite their success, fenced safe havens face several ecological and economic constraints. There is a need to explore additional approaches to restore species beyond the fence.

Aims

To explore naturally occurring mesas as potential ‘sky-island safe havens’, created by natural barriers in elevation and relief, which may restrict the movement of introduced predators and other mammals.

Methods

We examined species occurrences at a mesa site (Mt. Talaterang in south-east NSW, Australia) as well as a nearby lower-lying site (Little Forest Plateau). We then provide a geospatial analysis of other mesas in NSW to investigate the number of potential sky-island safe havens in the state.

Key results

Species assemblages differed between the two sites, with red foxes (Vulpes vulpes), dingoes/domestic dogs (Canis dingo/familiaris), and European rabbits (Oryctolagus cuniculus) absent from the mesa site, while Antechinus spp. were not detected from the lower-lying site. Feral cats (Felis catus) occurred at significantly lower densities on the mesa site compared to the lower-lying site. In NSW, we identified 91 other mesas of ≥10 ha with similar topology as Mt. Talaterang.

Conclusions

Although differences in species assemblages are expected between different habitats, the absence of red foxes and lower number of feral cat detections at the mesa site suggest the need to further explore the potential for mesas in conservation initiatives.

Implications

Our findings introduce a supplementary conservation strategy that could augment existing fenced safe haven approaches.

Keywords: conservation management, conservation translocation, invasive species, mesa, rewilding, reintroduction, safe haven, threatened species.

References

Agarwal K, Bode M (2019) Modelling the effects of leaky predator-exclusion fences and their surrounding halo [Preprint]. bioRxiv
| Crossref | Google Scholar |

Anderson MJ, Gorley RN, Clarke KR (2008) ‘PERMANOVA + for PRIMER: guide to software and statistical methods.’ (PRIMER-E: Plymouth)

Cairns KM, Crowther MS, Nesbitt B, Letnic M (2021) The myth of wild dogs in Australia: are there any out there? Australian Mammalogy 44, 67-75.
| Crossref | Google Scholar |

Clarke KR, Gorley RN (2015) ‘PRIMER v7: user manual/tutorial.’ (PRIMER-E: Plymouth)

Dickman CR (2012) Fences or ferals? Benefits and costs of conservation fencing in Australia. In ‘Fencing for conservation: restriction of evolutionary potential or a riposte to threatening processes?’. (Eds M Somers, M Hayward) pp. 43–63. (Springer: New York) doi:10.1007/978-1-4614-0902-1

Doherty TS, Dickman CR, Johnson CN, Legge SM, Ritchie EG, Woinarski JCZ (2017) Impacts and management of feral cats Felis catus in Australia. Mammal Review 47, 83-97.
| Crossref | Google Scholar |

Evans MJ, Batson WG, Gordon IJ, Belton E, Chaseling T, Fletcher D, Harrison M, McElroy T, Mungoven A, Newport J, Pierson J, Portas T, Swain S, Wimpenny C, Manning AD (2021) The ‘Goldilocks Zone’ of predation: the level of fox control needed to select predator resistance in a reintroduced mammal in Australia. Biodiversity and Conservation 30, 1731-1752.
| Crossref | Google Scholar |

Gallant J, Wilson N, Tickle PK, Dowling T, Read A (2009) 3 second SRTM derived Digital Elevation Model (DEM). Available at https://dev.ecat.ga.gov.au/geonetwork/srv/api/records/a05f7892-ef04-7506-e044-00144fdd4fa6 [Accessed 1 September 2023]

Hardman B, Moro D (2006) Optimising reintroduction success by delayed dispersal: Is the release protocol important for hare-wallabies? Biological Conservation 128, 403-411.
| Crossref | Google Scholar |

Hill JE, DeVault TL, Belant JL (2021) A review of ecological factors promoting road use by mammals. Mammal Review 51(2), 214-227.
| Crossref | Google Scholar |

Hradsky BA, Mildwaters C, Ritchie EG, Christie F, Di Stefano J (2017) Responses of invasive predators and native prey to a prescribed forest fire. Journal of Mammalogy 98, 835-847.
| Crossref | Google Scholar |

Jenness J (2008) Topographic Position Index (TPI) an ArcView 3.X tool for analyzing the shape of the landscape. Available at https://www.jennessent.com/arcview/tpi.htm [Accessed 1 September 2023]

Johnson CN, Isaac JL (2009) Body mass and extinction risk in Australian marsupials: the ‘Critical Weight Range’ revisited. Austral Ecology 34, 35-40.
| Crossref | Google Scholar |

Legge S, Woinarski JCZ, Burbidge AA, Palmer R, Ringma J, Radford JQ, Mitchell N, Bode M, Wintle B, Baseler M, Bentley J, Copley P, Dexter N, Dickman CR, Gillespie GR, Hill B, Johnson CN, Latch P, Letnic M, Manning A, McCreless EE, Menkhorst P, Morris K, Moseby K, Page M, Pannell D, Tuft K (2018) Havens for threatened Australian mammals: The contributions of fenced areas and offshore islands to the protection of mammal species susceptible to introduced predators. Wildlife Research 45, 627-644.
| Crossref | Google Scholar |

Lehmberg ES, Elbassiouny AA, Bloom DD, López-Fernández H, Crampton WGR, Lovejoy NR (2018) Fish biogeography in the “Lost World” of the Guiana Shield: phylogeography of the weakly electric knifefish Gymnotus carapo (Teleostei: Gymnotidae). Journal of Biogeography 45, 815-825.
| Crossref | Google Scholar |

McDonald PJ, Pavey CR, Knights K, Grantham D, Ward SJ, Nano CEM (2013) Extant population of the critically endangered central rock-rat Zyzomys pedunculatus located in the Northern Territory, Australia. Oryx 47, 303-306.
| Crossref | Google Scholar |

McDonald PJ, Brittingham R, Nano C, Paltridge R (2014) A new population of the critically endangered central rock-rat (Zyzomys pedunculatus) discovered in the Northern Territory. Australian Mammalogy 37, 97-100.
| Crossref | Google Scholar |

McDonald PJ, Griffiths AD, Nano CEM, Dickman CR, Ward SJ, Luck GW (2015) Landscape-scale factors determine occupancy of the critically endangered central rock-rat in arid Australia: the utility of camera trapping. Biological Conservation 191, 93-100.
| Crossref | Google Scholar |

McDonald PJ, Stewart A, Jensen MA, McGregor HW (2020) Topographic complexity potentially mediates cat predation risk for a critically endangered rodent. Wildlife Research 47(8), 643-648.
| Crossref | Google Scholar |

Miranda CV, Schwartsburd PB, Labiak PH, Prado J (2021) Three new species of Oleandra (Oleandraceae, Polypodiopsida) from the Neotropics, and notes on the morphological groups among the Neotropical species. Brittonia 73, 143-151.
| Crossref | Google Scholar |

Moseby KE, Peacock DE, Read JL (2015) Catastrophic cat predation: A call for predator profiling in wildlife protection programs. Biological Conservation 191, 331-340.
| Crossref | Google Scholar |

Moseby KE, McGregor H, Hill BM, Read JL (2020a) Exploring the internal and external wildlife gradients created by conservation fences. Conservation Biology 34, 220-231.
| Crossref | Google Scholar | PubMed |

Moseby KE, McGregor H, Read JL (2020b) Effectiveness of the Felixer grooming trap for the control of feral cats: a field trial in arid South Australia. Wildlife Research 47, 599-609.
| Crossref | Google Scholar |

Moseby KE, McGregor H, Read JL (2021) The lethal 23%: predator demography influences predation risk for threatened prey. Animal Conservation 24, 217-229.
| Crossref | Google Scholar |

Nano CEM, Randall DJ, Stewart AJ, Pavey CR, McDonald PJ (2019) Spatio-temporal gradients in food supply help explain the short-term colonisation dynamics of the critically endangered central rock-rat (Zyzomys pedunculatus). Austral Ecology 44(5), 838-849.
| Crossref | Google Scholar |

Pavey CR, Addison J, Brandle R, Dickman CR, McDonald PJ, Moseby KE, Young LI (2017) The role of refuges in the persistence of Australian dryland mammals. Biological Reviews 92, 647-664.
| Crossref | Google Scholar |

Posit Team (2023) RStudio: integrated development environment for R. Available at http://www.posit.co/ [Accessed 1 March 2023]

QGIS.org (2023) QGIS geographic information system. Available at QGIS.org [Accessed 1 June 2023]

Radford JQ, Woinarski JCZ, Legge S, Baseler M, Bentley J, Burbidge AA, Bode M, Copley P, Dexter N, Dickman CR, Gillespie G, Hill B, Johnson CN, Kanowski J, Latch P, Letnic M, Manning A, Menkhorst P, Mitchell N, Morris K, Moseby K, Page M, Ringma J (2018) Degrees of population-level susceptibility of Australian terrestrial non-volant mammal species to predation by the introduced red fox (Vulpes vulpes) and feral cat (Felis catus). Wildlife Research 45, 645-657.
| Crossref | Google Scholar |

Raiter KG, Hobbs RJ, Possingham HP, Valentine LE, Prober SM (2018) Vehicle tracks are predator highways in intact landscapes. Biological Conservation 228, 281-290.
| Crossref | Google Scholar |

Ramírez-Prieto J, Koch-Olt S, de Jesús Balleza-Cadengo J, Adame-González M, Romero-Nápoles J (2016) Flora on summit of the Mesa Alta, Jerez, Zacatecas, México. Botanical Sciences 94, 357-375.
| Crossref | Google Scholar |

Ringma J, Legge S, Woinarski J, Radford J, Wintle B, Bode M (2018) Australia’s mammal fauna requires a strategic and enhanced network of predator-free havens. Nature Ecology and Evolution 2, 410-411.
| Crossref | Google Scholar | PubMed |

Ward M, Tulloch AIT, Radford JQ, Williams BA, Reside AE, Macdonald SL, Mayfield HJ, Maron M, Possingham HP, Vine SJ, O’Connor JL, Massingham EJ, Greenville AC, Woinarski JCZ, Garnett ST, Lintermans M, Scheele BC, Carwardine J, Nimmo DG, Lindenmayer DB, Kooyman RM, Simmonds JS, Sonter LJ, Watson JEM (2020) Impact of 2019–2020 mega-fires on Australian fauna habitat. Nature Ecology & Evolution 4, 1321-1326.
| Crossref | Google Scholar | PubMed |

Weiss AD (2001) Topographic position and landforms analysis. Available at https://www.jennessent.com/arcview/tpi.htm [Accessed 1 September 2023]

Wildlife Insights (2022) WildlifeInsights.org. Available at https://www.wildlifeinsights.org/ [Accessed 1 April 2022]

Wilson BA, Evans MJ, Gordon IJ, Banks SC, Batson WG, Wimpenny C, Newport J, Manning AD (2022) Personality and plasticity predict postrelease performance in a reintroduced mesopredator. Animal Behaviour 187, 177-189.
| Crossref | Google Scholar |

Woinarski JCZ, Burbidge AA, Harrison PL (2015) Ongoing unraveling of a continental fauna: Decline and extinction of Australian mammals since European settlement. Proceedings of the National Academy of Sciences of the United States of America 112, 4531-4540.
| Crossref | Google Scholar |