Free Standard AU & NZ Shipping For All Book Orders Over $80!
Register      Login
Wildlife Research Wildlife Research Society
Ecology, management and conservation in natural and modified habitats
RESEARCH ARTICLE

Evidence of significantly higher island feral cat abundance compared with the adjacent mainland

Patrick L. Taggart https://orcid.org/0000-0001-9523-0463 A H , Bronwyn A. Fancourt https://orcid.org/0000-0003-2969-1530 B C , Andrew J. Bengsen D , David E. Peacock https://orcid.org/0000-0003-2891-8238 A E , Patrick Hodgens F , John L. Read G , Milton M. McAllister A * and Charles G. B. Caraguel A *
+ Author Affiliations
- Author Affiliations

A School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, SA 5371, Australia.

B Pest Animal Research Centre, Biosecurity Queensland, Department of Agriculture and Fisheries, Toowoomba, Qld 4350, Australia.

C School of Environmental and Rural Science, University of New England, Armidale, NSW 2350, Australia.

D Vertebrate Pest Research Unit, Department of Primary Industries, Orange, NSW 2800, Australia.

E Biosecurity South Australia, Adelaide, SA 5001, Australia.

F Terrain Ecology, PO Box 966, Kingscote, SA 5223, Australia.

G School of Earth and Environmental Sciences, The University of Adelaide, Adelaide, SA 5005, Australia.

H Corresponding author. Email: patrick.taggart@adelaide.edu.au

Wildlife Research 46(5) 378-385 https://doi.org/10.1071/WR18118
Submitted: 18 July 2018  Accepted: 31 March 2019   Published: 4 July 2019

Abstract

Context: Feral cats (Felis catus) impact the health and welfare of wildlife, livestock and humans worldwide. They are particularly damaging where they have been introduced into island countries such as Australia and New Zealand, where native prey species evolved without feline predators. Kangaroo Island, in South Australia, is Australia’s third largest island and supports several threatened and endemic species. Cat densities on Kangaroo Island are thought to be greater than those on the adjacent South Australian mainland, based on one cat density estimate on the island that is higher than most estimates from the mainland. The prevalence of cat-borne disease in cats and sheep is also higher on Kangaroo Island than the mainland, suggesting higher cat densities. A recent continental-scale spatial model of cat density predicted that cat density on Kangaroo Island should be about double that of the adjacent mainland. However, although cats are believed to have severe impacts on some native species on the island, other species that are generally considered vulnerable to cat predation have relatively secure populations on the island compared with the mainland.

Aims: The present study aimed to compare feral cat abundance between Kangaroo Island and the adjacent South Australian mainland using simultaneous standardised methods. Based on previous findings, we predicted that the relative abundance of feral cats on Kangaroo Island would be approximately double that on the South Australian mainland.

Methods: Standardised camera trap surveys were used to simultaneously estimate the relative abundance of feral cats on Kangaroo Island and the adjacent South Australian mainland. Survey data were analysed using the Royle–Nichols abundance-induced heterogeneity model to estimate feral cat relative abundance at each site.

Key results: Cat abundance on the island was estimated to be over 10 times greater than that on the adjacent mainland.

Conclusions: Consistent with predictions, cat abundance on the island was greater than on the adjacent mainland. However, the magnitude of this difference was much greater than expected.

Implications: The findings show that the actual densities of cats at local sites can vary substantially from predictions generated by continental-scale models. The study also demonstrates the value of estimating abundance or density simultaneously across sites using standardised methods.

Additional keywords: feline, Felis catus, insular, invasive predator, invasive species, pest management.


References

Australian Government Bureau of Meteorology (BOM) (2017). Climate data online. Available at http://www.bom.gov.au/climate/data/ [verified April 2019].

Bates, D., Maechler, M., Bolker, B., and Walker, S. (2015). Fitting linear mixed-effects models using lme4. Journal of Statistical Software 67, 1–48.
Fitting linear mixed-effects models using lme4.Crossref | GoogleScholarGoogle Scholar |

Bengsen, A., Butler, J., and Masters, P. (2011a). Estimating and indexing feral cat population abundances using camera traps. Wildlife Research 38, 732–739.
Estimating and indexing feral cat population abundances using camera traps.Crossref | GoogleScholarGoogle Scholar |

Bengsen, A. J., Leung, L. K. P., Lapidge, S. J., and Gordon, I. J. (2011b). Using a general index approach to analyze camera‐trap abundance indices. The Journal of Wildlife Management 75, 1222–1227.
Using a general index approach to analyze camera‐trap abundance indices.Crossref | GoogleScholarGoogle Scholar |

Bengsen, A. J., Butler, J. A., and Masters, P. (2012). Applying home-range and landscape-use data to design effective feral-cat control programs. Wildlife Research 39, 258–265.
Applying home-range and landscape-use data to design effective feral-cat control programs.Crossref | GoogleScholarGoogle Scholar |

Bengsen, A., Algar, D., Ballard, G., Buckmaster, T., Comer, S., Fleming, P., Friend, J., Johnston, M., McGregor, H., and Moseby, K. (2016). Feral cat home‐range size varies predictably with landscape productivity and population density. Journal of Zoology 298, 112–120.
Feral cat home‐range size varies predictably with landscape productivity and population density.Crossref | GoogleScholarGoogle Scholar |

Berdoy, M., Webster, J. P., and Macdonald, D. (2000). Fatal attraction in rats infected with Toxoplasma gondii. Proceedings of the Royal Society of London. Series B, Biological Sciences 267, 1591–1594.
Fatal attraction in rats infected with Toxoplasma gondii.Crossref | GoogleScholarGoogle Scholar |

Bonnington, C., Gaston, K. J., and Evans, K. L. (2013). Fearing the feline: domestic cats reduce avian fecundity through trait‐mediated indirect effects that increase nest predation by other species. Journal of Applied Ecology 50, 15–24.
Fearing the feline: domestic cats reduce avian fecundity through trait‐mediated indirect effects that increase nest predation by other species.Crossref | GoogleScholarGoogle Scholar |

Burbidge, A. A., and Manly, B. F. (2002). Mammal extinctions on Australian islands: causes and conservation implications. Journal of Biogeography 29, 465–473.
Mammal extinctions on Australian islands: causes and conservation implications.Crossref | GoogleScholarGoogle Scholar |

Canfield, P., Hartley, W., and Dubey, J. (1990). Lesions of toxoplasmosis in Australian marsupials. Journal of Comparative Pathology 103, 159–167.
Lesions of toxoplasmosis in Australian marsupials.Crossref | GoogleScholarGoogle Scholar | 2246391PubMed |

Catling, P. (1988). Similarities and contrasts in the diets of foxes, Vulpes vulpes, and cats, Felis catus, relative to fluctuating prey populations and drought. Wildlife Research 15, 307–317.
Similarities and contrasts in the diets of foxes, Vulpes vulpes, and cats, Felis catus, relative to fluctuating prey populations and drought.Crossref | GoogleScholarGoogle Scholar |

Clare, J. D., Anderson, E. M., and MacFarland, D. M. (2015). Predicting bobcat abundance at a landscape scale and evaluating occupancy as a density index in central Wisconsin. The Journal of Wildlife Management 79, 469–480.
Predicting bobcat abundance at a landscape scale and evaluating occupancy as a density index in central Wisconsin.Crossref | GoogleScholarGoogle Scholar |

Courchamp, F., Chapuis, J.-L., and Pascal, M. (2003). Mammal invaders on islands: impact, control and control impact. Biological Reviews of the Cambridge Philosophical Society 78, 347–383.
Mammal invaders on islands: impact, control and control impact.Crossref | GoogleScholarGoogle Scholar | 14558589PubMed |

Dubey, J. P. (2016). ‘Toxoplasmosis of Animals and Humans.’ 2nd edn. (CRC Press: Boca Raton, FL.)

Dubey, J., Rollor, E., Smith, K., Kwok, O., and Thulliez, P. (1997). Low seroprevalence of Toxoplasma gondii in feral pigs from a remote island lacking cats. The Journal of Parasitology 83, 839–841.
Low seroprevalence of Toxoplasma gondii in feral pigs from a remote island lacking cats.Crossref | GoogleScholarGoogle Scholar | 9379287PubMed |

Elizondo, E. C., and Loss, S. R. (2016). Using trail cameras to estimate free-ranging domestic cat abundance in urban areas. Wildlife Biology 22, 246–252.
Using trail cameras to estimate free-ranging domestic cat abundance in urban areas.Crossref | GoogleScholarGoogle Scholar |

Engeman, R. M. (2005). Indexing principles and a widely applicable paradigm for indexing animal populations. Wildlife Research 32, 203–210.
Indexing principles and a widely applicable paradigm for indexing animal populations.Crossref | GoogleScholarGoogle Scholar |

Fancourt, B. A. (2016). Avoiding the subject: the implications of avoidance behaviour for detecting predators. Behavioral Ecology and Sociobiology 70, 1535–1546.
Avoiding the subject: the implications of avoidance behaviour for detecting predators.Crossref | GoogleScholarGoogle Scholar |

Fancourt, B. A., and Jackson, R. B. (2014). Regional seroprevalence of Toxoplasma gondii antibodies in feral and stray cats (Felis catus) from Tasmania. Australian Journal of Zoology 62, 272–283.
Regional seroprevalence of Toxoplasma gondii antibodies in feral and stray cats (Felis catus) from Tasmania.Crossref | GoogleScholarGoogle Scholar |

Fancourt, B. A., Sweaney, M., and Fletcher, D. B. (2018). More haste, less speed: pilot study suggests camera trap detection zone could be more important than trigger speed to maximise species detections. Australian Mammalogy 40, 118–121.
More haste, less speed: pilot study suggests camera trap detection zone could be more important than trigger speed to maximise species detections.Crossref | GoogleScholarGoogle Scholar |

Fiske, I., and Chandler, R. (2011). unmarked: an R Package for fitting hierarchical models of wildlife occurrence and abundance. Journal of Statistical Software 43, 1–23.
unmarked: an R Package for fitting hierarchical models of wildlife occurrence and abundance.Crossref | GoogleScholarGoogle Scholar |

Fredebaugh, S. L., Mateus-Pinilla, N. E., McAllister, M., Warner, R. E., and Weng, H.-Y. (2011). Prevalence of antibody to Toxoplasma gondii in terrestrial wildlife in a natural area. Journal of Wildlife Diseases 47, 381–392.
Prevalence of antibody to Toxoplasma gondii in terrestrial wildlife in a natural area.Crossref | GoogleScholarGoogle Scholar | 21441191PubMed |

Gates, J. A., and Paton, D. C. (2005). The distribution of bush stone-curlews (Burhinus grallarius) in South Australia, with particular reference to Kangaroo Island. Emu-Austral Ornithology 105, 241–247.
The distribution of bush stone-curlews (Burhinus grallarius) in South Australia, with particular reference to Kangaroo Island.Crossref | GoogleScholarGoogle Scholar |

Glen, A., Pennay, M., Dickman, C., Wintle, B., and Firestone, K. (2011). Diets of sympatric native and introduced carnivores in the Barrington Tops, eastern Australia. Austral Ecology 36, 290–296.
Diets of sympatric native and introduced carnivores in the Barrington Tops, eastern Australia.Crossref | GoogleScholarGoogle Scholar |

Hardman, B., Moro, D., and Calver, M. (2016). Direct evidence implicates feral cat predation as the primary cause of failure of a mammal reintroduction programme. Ecological Management & Restoration 17, 152–158.
Direct evidence implicates feral cat predation as the primary cause of failure of a mammal reintroduction programme.Crossref | GoogleScholarGoogle Scholar |

Heiniger, J., and Gillespie, G. (2018). High variation in camera trap-model sensitivity for surveying mammal species in northern Australia. Wildlife Research 45, 578–585.
High variation in camera trap-model sensitivity for surveying mammal species in northern Australia.Crossref | GoogleScholarGoogle Scholar |

Hohnen, R., Tuft, K., McGregor, H. W., Legge, S., Radford, I. J., and Johnson, C. N. (2016). Occupancy of the invasive feral cat varies with habitat complexity. PLoS One 11, e0152520.
Occupancy of the invasive feral cat varies with habitat complexity.Crossref | GoogleScholarGoogle Scholar | 27655024PubMed |

Jenkins, R. B. (1985). Parks of the Fleurieu Peninsula: draft management plan. Part 2: Fleurieu Peninsula – The Region. National Parks and Wildlife Service. Department of Environment and Planning SA, Adelaide.

Kowalski, M. (2011). Exifpro image viewer. Version 2.1. Available at http://www.exifpro.com/ [verified April 2019].

Laurance, W. F. (2008). Theory meets reality: how habitat fragmentation research has transcended island biogeographic theory. Biological Conservation 141, 1731–1744.
Theory meets reality: how habitat fragmentation research has transcended island biogeographic theory.Crossref | GoogleScholarGoogle Scholar |

Leeuwenburg, P. (2004). Roadkill on Kangaroo Island: identification of patterns and predictors of roadkill. Honours thesis. University of South Australia, Adelaide.

Legge, S., Murphy, B., McGregor, H., Woinarski, J., Augusteyn, J., Ballard, G., Baseler, M., Buckmaster, T., Dickman, C., Doherty, T., Edwards, G., Eyre, T., Fancourt, B. A., Ferguson, D., Maxwell, M., McDonald, P. J., Morris, K., Moseby, K., Newsome, T., Nimmo, D., Paltridge, R., Ramsey, D., Read, J., Rendall, A., Rich, M., Ritchie, E., Rowland, J., Short, J., Stokeld, D., Sutherland, D. R., Wayne, A. F., Woodford, L., and Zewe, F. (2017). Enumerating a continental-scale threat: how many feral cats are in Australia? Biological Conservation 206, 293–303.
Enumerating a continental-scale threat: how many feral cats are in Australia?Crossref | GoogleScholarGoogle Scholar |

Linden, D. W., Fuller, A. K., Royle, J. A., and Hare, M. P. (2017). Examining the occupancy–density relationship for a low‐density carnivore. Journal of Applied Ecology 54, 2043–2052.
Examining the occupancy–density relationship for a low‐density carnivore.Crossref | GoogleScholarGoogle Scholar |

MacKenzie, D. I., Nichols, J. D., Lachman, G. B., Droege, S., Andrew Royle, J., and Langtimm, C. A. (2002). Estimating site occupancy rates when detection probabilities are less than one. Ecology 83, 2248–2255.
Estimating site occupancy rates when detection probabilities are less than one.Crossref | GoogleScholarGoogle Scholar |

Mateus-Pinilla, N. E., Dubey, J., Choromanski, L., and Weigel, R. M. (1999). A field trial of the effectiveness of a feline Toxoplasma gondii vaccine in reducing T. gondii exposure for swine. The Journal of Parasitiology , 855–860.
A field trial of the effectiveness of a feline Toxoplasma gondii vaccine in reducing T. gondii exposure for swine.Crossref | GoogleScholarGoogle Scholar |

Mateus-Pinilla, N. E., Hannon, B., and Weigel, R. M. (2002). A computer simulation of the prevention of the transmission of Toxoplasma gondii on swine farms using a feline T. gondii vaccine. Preventive Veterinary Medicine 55, 17–36.
A computer simulation of the prevention of the transmission of Toxoplasma gondii on swine farms using a feline T. gondii vaccine.Crossref | GoogleScholarGoogle Scholar | 12324204PubMed |

McGregor, H., Legge, S., Jones, M. E., and Johnson, C. N. (2015). Feral cats are better killers in open habitats, revealed by animal-borne video. PLoS One 10, e0133915.
Feral cats are better killers in open habitats, revealed by animal-borne video.Crossref | GoogleScholarGoogle Scholar | 26288224PubMed |

Medina, F. M., Bonnaud, E., Vidal, E., Tershy, B. R., Zavaleta, E. S., Josh Donlan, C., Keitt, B. S., Corre, M., Horwath, S. V., and Nogales, M. (2011). A global review of the impacts of invasive cats on island endangered vertebrates. Global Change Biology 17, 3503–3510.
A global review of the impacts of invasive cats on island endangered vertebrates.Crossref | GoogleScholarGoogle Scholar |

Medina, F. M., Bonnaud, E., Vidal, E., and Nogales, M. (2014). Underlying impacts of invasive cats on islands: not only a question of predation. Biodiversity and Conservation 23, 327–342.
Underlying impacts of invasive cats on islands: not only a question of predation.Crossref | GoogleScholarGoogle Scholar |

Meek, P. D., Ballard, G., and Fleming, P. (2012). An introduction to camera trapping for wildlife surveys in Australia. Invasive Animals CRC, Canberra.

Meek, P. D., Ballard, G.-A., and Fleming, P. J. (2015). The pitfalls of wildlife camera trapping as a survey tool in Australia. Australian Mammalogy 37, 13–22.
The pitfalls of wildlife camera trapping as a survey tool in Australia.Crossref | GoogleScholarGoogle Scholar |

Molsher, R. L. (1999). The ecology of feral cats, Felis catus, in open forest in New South Wales: interactions with food resources and foxes. Ph.D. Thesis, The University of Sydney, Sydney, NSW, Australia.

Moseby, K. E., Hill, B. M., and Read, J. L. (2009). Arid recovery – a comparison of reptile and small mammal populations inside and outside a large rabbit, cat and fox‐proof exclosure in arid South Australia. Austral Ecology 34, 156–169.
Arid recovery – a comparison of reptile and small mammal populations inside and outside a large rabbit, cat and fox‐proof exclosure in arid South Australia.Crossref | GoogleScholarGoogle Scholar |

Myers, N., Mittermeier, R. A., Mittermeier, C. G., Da Fonseca, G. A., and Kent, J. (2000). Biodiversity hotspots for conservation priorities. Nature 403, 853–858.
Biodiversity hotspots for conservation priorities.Crossref | GoogleScholarGoogle Scholar | 10706275PubMed |

Noon, B. R., Bailey, L. L., Sisk, T. D., and McKelvey, K. S. (2012). Efficient species‐level monitoring at the landscape scale. Conservation Biology 26, 432–441.
Efficient species‐level monitoring at the landscape scale.Crossref | GoogleScholarGoogle Scholar | 22594594PubMed |

O’Callaghan, M., Reddin, J., and Dehmann, D. (2005). Helminth and protozoan parasites of feral cats from Kangaroo Island. Transactions of the Royal Society of South Australia 129, 81–83.

O’Donoghue, P. J., Riley, M. J., and Clarke, J. F. (1987). Serological survey for Toxoplasma infections in sheep. Australian Veterinary Journal 64, 40–45.
Serological survey for Toxoplasma infections in sheep.Crossref | GoogleScholarGoogle Scholar | 3606503PubMed |

Paull, D. (1995). The distribution of the southern brown bandicoot (Isoodon obesulus obesulus) in South Australia. Wildlife Research 22, 585–599.
The distribution of the southern brown bandicoot (Isoodon obesulus obesulus) in South Australia.Crossref | GoogleScholarGoogle Scholar |

Polis, G. A., and Hurd, S. D. (1996). Linking marine and terrestrial food webs: allochthonous input from the ocean supports high secondary productivity on small islands and coastal land communities. American Naturalist 147, 396–423.
Linking marine and terrestrial food webs: allochthonous input from the ocean supports high secondary productivity on small islands and coastal land communities.Crossref | GoogleScholarGoogle Scholar |

R Core Team (2018). ‘R: A language and environment for statistical computing.’ (R Foundation for Statistical Computing: Vienna.) Available at https://www.R-project.org/ [verified 12 January 2018].

Read, J., and Bowen, Z. (2001). Population dynamics, diet and aspects of the biology of feral cats and foxes in arid South Australia. Wildlife Research 28, 195–203.
Population dynamics, diet and aspects of the biology of feral cats and foxes in arid South Australia.Crossref | GoogleScholarGoogle Scholar |

Read, J., Bengsen, A., Meek, P., and Moseby, K. (2015). How to snap your cat: optimum lures and their placement for attracting mammalian predators in arid Australia. Wildlife Research 42, 1–12.
How to snap your cat: optimum lures and their placement for attracting mammalian predators in arid Australia.Crossref | GoogleScholarGoogle Scholar |

Risbey, D. A., Calver, M. C., Short, J., Bradley, J. S., and Wright, I. W. (2000). The impact of cats and foxes on the small vertebrate fauna of Heirisson Prong, Western Australia. II. A field experiment. Wildlife Research 27, 223–235.
The impact of cats and foxes on the small vertebrate fauna of Heirisson Prong, Western Australia. II. A field experiment.Crossref | GoogleScholarGoogle Scholar |

Rismiller, P. (1999). ‘The Echidna: Australia’s Enigma.’ (Hugh Lauter Levin Associates: Fairfield, CT.)

Rismiller, P. D., and McKelvey, M. W. (2000). Frequency of breeding and recruitment in the short-beaked echidna, Tachyglossus aculeatus. Journal of Mammalogy 81, 1–17.
Frequency of breeding and recruitment in the short-beaked echidna, Tachyglossus aculeatus.Crossref | GoogleScholarGoogle Scholar |

Royle, J. A., and Nichols, J. D. (2003). Estimating abundance from repeated presence-absence data or point counts. Ecology 84, 777–790.
Estimating abundance from repeated presence-absence data or point counts.Crossref | GoogleScholarGoogle Scholar |

Salo, P., Korpimäki, E., Banks, P. B., Nordström, M., and Dickman, C. R. (2007). Alien predators are more dangerous than native predators to prey populations. Proceedings of the Royal Society of London. Series B, Biological Sciences 274, 1237–1243.
Alien predators are more dangerous than native predators to prey populations.Crossref | GoogleScholarGoogle Scholar |

Schwerdtfeger, P. (2002). ‘Natural History of Kangaroo Island. Chapter 5 ‘Climate’.’ (Royal Society of South Australia: Adelaide.)

Short, J., Richards, J., and Turner, B. (1998). Ecology of the western barred bandicoot (Perameles bougainville)(Marsupialia: Peramelidae) on Dorre and Bernier Islands, Western Australia. Wildlife Research 25, 567–586.
Ecology of the western barred bandicoot (Perameles bougainville)(Marsupialia: Peramelidae) on Dorre and Bernier Islands, Western Australia.Crossref | GoogleScholarGoogle Scholar |

Wallace, G. D., Marshall, L., and Marshall, M. (1972). Cats, rats, and toxoplasmosis on a small Pacific island. American Journal of Epidemiology 95, 475–482.
Cats, rats, and toxoplasmosis on a small Pacific island.Crossref | GoogleScholarGoogle Scholar | 5063197PubMed |

Woinarski, J. C., Burbidge, A. A., and Harrison, P. L. (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.
Ongoing unraveling of a continental fauna: decline and extinction of Australian mammals since European settlement.Crossref | GoogleScholarGoogle Scholar | 25675493PubMed |