Patterns of human–crocodile conflict in Queensland: a review of historical estuarine crocodile (Crocodylus porosus) management
M. L. Brien A D , C. M. Gienger B , C. A. Browne A , M. A. Read C , M. J. Joyce A and S. Sullivan AA Department of Environment and Heritage Protection, PO Box 375, Garbutt East LPO, Qld 4870, Australia.
B Department of Biology and Center of Excellence for Field Biology, Austin Peay State University, Clarksville, Tennessee 37044, USA.
C Great Barrier Reef Marine Park Authority, PO Box 1379, Townsville, Qld 4810, Australia.
D Corresponding author. Email: matt.brien@ehp.qld.gov.au
Wildlife Research 44(4) 281-290 https://doi.org/10.1071/WR17011
Submitted: 9 February 2017 Accepted: 24 June 2017 Published: 29 August 2017
Abstract
Context: In Queensland, the management of estuarine crocodiles (Crocodylus porosus) by the government is important for ensuring public safety, especially along the populated east coast, where there is a large human population.
Aims: The present study aimed to determine historical, temporal and spatial patterns of human–crocodile conflict in Queensland.
Methods: The study used Queensland Government records of estuarine crocodile attacks (1971–2015), sightings by the general public (2003–2015), and removals and relocations for management purposes (1985–2015) to develop General Linear Models describing historical, temporal and spatial patterns.
Key results: The highest number of attacks, sightings, removals and relocations occurred along the populated east coast between Townsville and the Daintree during wet season months (November–February). There have been 35 crocodile attacks in Queensland since 1971 (total 0.8 per year; fatal 0.3 per year), mostly involving local people or regular visitors (77.1%), specifically adult males (71.4%; mean age 44). There has been an increase in the rate of crocodile attacks over time, with an average of 1.3 per year since 1996, most of which were non-fatal (84%). The number of crocodile sightings has been increasing annually (with a mean of 348 per year since 2011), while the number of crocodiles removed or relocated for management purposes (n = 608) has fluctuating widely each year (range 1–57).
Conclusions: The level of human–crocodile conflict in Queensland is increasing, and this is likely to be a consequence of increasing human and crocodile populations. While conflict is highest during the wet season, estuarine crocodiles pose a threat to public safety year round.
Implications: With the increase in conflict, the ongoing management of estuarine crocodiles, through targeted removals in and around areas of higher human habitation and through education, is essential for ensuring public safety into the future.
Additional keywords: attacks, removals, sightings.
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