Aerial shooting is unlikely to cause dispersal or consistent changes in the movements of feral pigs (Sus scrofa)

Andrew J. Bengsen; Sebastien Comte; Troy Crittle; Suzie Holbery; Darren Marshall; Lachlan Marshall; Lee Parker; David M. Forsyth

doi:10.1071/WR25024

RESEARCH ARTICLE (Open Access)

Contents Vol 52(6)

Aerial shooting is unlikely to cause dispersal or consistent changes in the movements of feral pigs (Sus scrofa)

Andrew J. Bengsen

^A ^* , Sebastien Comte

^B ^C , Troy Crittle ^D , Suzie Holbery ^E , Darren Marshall ^F , Lachlan Marshall ^F , Lee Parker ^A and David M. Forsyth

^B ^C

+ Author Affiliations

- Author Affiliations

^A NSW Department of Primary Industries and Regional Development, Vertebrate Pest Research Unit, 4 Marsden Park Road, Calala, NSW 2340, Australia.

^B NSW Department of Primary Industries and Regional Development, Vertebrate Pest Research Unit, 1447 Forest Road, Orange, NSW 2800, Australia.

^C Evolution & Ecology Research Centre, The University of New South Wales, Sydney, NSW, Australia.

^D NSW Department of Primary Industries and Regional Development, 4 Marsden Park Road, Calala, NSW 2340, Australia.

^E Riverina Local Land Services, 56 Lachlan Street, Hay, NSW 2711, Australia.

^F Centre for Invasive Species Solutions, University of Canberra, Building 22, University Drive, Bruce, ACT 2617, Australia.

^* Correspondence to: andrew.bengsen@dpi.nsw.gov.au

Handling Editor: Penny Fisher

Wildlife Research 52, WR25024 https://doi.org/10.1071/WR25024

Submitted: 21 February 2025 Accepted: 11 May 2025 Published: 29 May 2025

© 2025 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

Aerial shooting is an important tool for managing feral pig damage to agricultural and biodiversity assets because it can rapidly reduce population densities over large areas. It should also be valuable for reducing host population densities in the event of an emergency animal disease incursion. However, recent tracking studies have not alleviated concerns that the intense disturbance caused by aerial shooting might cause pigs to disperse from target areas.

Aims

We investigated the responses of feral pigs to nine aerial shooting operations conducted at five large and divergent sites in south-eastern Australia.

Methods

We fitted 71 pigs with GPS tracking collars and monitored changes in their behaviour following exposure to aerial shooting operations that lasted between 1 and 11 days. Repeated exposure of some individuals provided 105 distinct samples. We examined the following three key traits: the location and size of activity ranges, daily activity and movement rates, and daily activity cycles.

Key results

We found inconsistent results between sexes and among operations. However, only one pig left the target area after shooting began. This pig did not return.

Conclusions

The fine-scale behaviour of pigs subjected to aerial shooting is likely to vary because of a complex interplay of social, environmental, and operational factors. Behaviour changes observed in this study were unlikely to cause the dispersal of feral pigs or their impacts.

Implications

Given our results, and those of previous studies, we believe that aerial shooting should continue to be used as a key method for managing feral pig populations and should also be considered for emergency animal disease response operations.

Keywords: aerial culling, behavioural responses, depopulation, feral swine, GPS tracking, movement ecology, population control, transboundary animal disease, wild boar, wildlife management.

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