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Ecology, management and conservation in natural and modified habitats
RESEARCH ARTICLE

The canid pest ejector challenge: controlling urban foxes while keeping domestic dogs safe

Margarita Gil-Fernández https://orcid.org/0000-0002-2918-1701 A E , Robert Harcourt A , Alison Towerton B , Thomas Newsome C , Hayley A. Milner A , Sanjana Sriram A , Natalie Gray A , Sergio Escobar-Lasso D , Victor Hugo González-Cardoso A and Alexandra Carthey A
+ Author Affiliations
- Author Affiliations

A Department of Biological Sciences, Macquarie University, Balaclava Road, North Ryde, Sydney, NSW 2109, Australia.

B Greater Sydney Local Land Services, Level 4, 2–6 Station Street, PO Box 4515, Penrith (Westfield), NSW 2750, Australia.

C School of Life and Environmental Sciences, The University of Sydney, Room 312, Heydon-Laurence Building A08, Sydney, NSW 2006, Australia.

D Proyecto de Conservación de Aguas y Tierras, ProCAT Colombia/International, Carrera 11 #96-43, Office 303, Bogotá, Colombia.

E Corresponding author. Email: mgilfedz@gmail.com

Wildlife Research 48(4) 314-322 https://doi.org/10.1071/WR20078
Submitted: 7 May 2020  Accepted: 4 October 2020   Published: 24 March 2021

Abstract

Context: It is widely recognised that red foxes (Vulpes vulpes) are abundant within urban areas; however, it is difficult to apply lethal control measures using poison baits in cities because of concerns about the safety of domestic pets, particularly dogs (Canis familiaris).

Aims: We tested canid pest ejectors (CPEs) as a potential method of fox control by measuring visitation and activation behaviour of foxes and other wildlife while assessing non-target risk to domestic dogs.

Methods: We compared eight urban and eight peri-urban sites in Sydney, with half of the sites having restricted access for domestic dogs. We allocated five camera traps and ejectors per site. Through generalised linear mixed models, we compared the probability of ejector activation between foxes and dogs. We also assessed the relationship between dog visitation and distance to habitation and dog restrictions as measures of dog safety.

Key results: Both species of canids were equally likely to pull the ejector (P = 0.26). As expected, dog visitation was significantly lower in sites with dog restrictions (P < 0.001). However, it was not related to distance from habitation. Only two non-canid species were recorded pulling the ejector, suggesting high target-specificity for canids.

Conclusions: In sites with dog restrictions, the risk of dog casualties from CPEs is minimal. However, distance from habitation does not increase dog safety, at least within 250 m. The ejector is highly specific for canids.

Implications: We provide specific recommendations for the design of a potential fox control program using CPEs in urban and peri-urban areas. The ejector may be a safe method for fox control in cities when deployed at places without domestic dogs.

Keywords: invasive predator, lethal control, M-44 ejector, pest control, urban carnivore, urban ecology.


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