Cost-effective management of wild deer

Summary

Wild deer are present in all Australian states and territories and are causing increasing agricultural, environmental and social impacts. The six species of deer occupy a wide variety of habitats including rangeland (chital deer), agricultural (fallow deer), plantation forests (sambar deer and red deer), and montane forest (sambar deer).  

Land managers have started to use aerial shooting, ground shooting and exclusion fencing to manage wild deer, but the cost-effectiveness and appropriateness of these methods have not been evaluated. Best-practice guidelines for managing wild deer were identified as a priority need at the 2016 National Wild Deer Management Workshop.  

This five-year project will provide land managers with the tools and expertise required to cost-effectively manage wild deer. The project will provide national leadership through the coordination of existing and planned deer management programs in QLD, NSW, VIC and TAS.   

Status

Completed

Objectives

This project has four key objectives: 

  1. In collaboration with the associated organisations, establish demonstration sites at which on-ground management, research and training will occur in NSW, QLD, VIC and TAS. 
  2. Evaluate the costs and efficacy of the main control tools (i.e. aerial shooting and ground shooting) at demonstration sites, supported by population modelling to assess longer-term impacts of control on deer populations. 
  3. Disseminate knowledge widely through: field days at demonstration sites; presentations at workshops, symposia and conferences; media releases; articles in peer-reviewed journals; and best-practice guidelines available from the PestSmart website. 
  4. Build technical and research capacity in wild deer management by up-skilling research and technical staff involved in vertebrate pest management and by training post-graduate students. 

Project Leader



Dr Dave Forsyth
Project Team
  • Dr Dave Forsyth, NSW DPI
  • Dr Andrew Bengsen, NSW DPI 
  • Troy Crittle, NSW DPI 
  • Dr Tony Pople, QDAF 
  • Michael Brennan, QDAF 
  • Matt Amos, QDAF 
  • Dr Dave Ramsey, VIC DELWP 
  • Richard Duncan, UC 
  • Bronwyn Cameron, NSW North West LLS 
  • Mal Leeson, NSW Central Tablelands LLS 
  • Ashley Blokland, Charters Towers Regional Council 
  • Elaine Thomas, Parks Victoria 
  • Sally Bryant, Tasmanian Land Conservancy 
  • Jordan Hampton, Ecotone Wildlife Veterinary Services 
Project Partners
  • New South Wales Department of Primary Industries  (NSW DPI)
  • Queensland Department of Agriculture and Fisheries (QDAF)
  • University of Canberra 
  • Tasmanian Land Conservancy
  • Ecotone Wildlife Vet Services
  • eSYS
  • Chatered Towers Regional Council

The project receives funding from the Australian Government Department of Agriculture, Water and Environment

Outputs

February 2021 update:

The first global systematic review of deer abundance and density estimation methods was completed. Spanning 2004-2018, deer abundance and density estimates show that most estimates available were for three main species. Most abundance estimates were negatively biased, but capture–recapture methods were the least biased. Substantial effort is expended estimating deer abundance and density.

August 2020 update:

Field work for the assessment of the welfare outcomes of aerial shooting of deer has been completed. This will form the basis of a best practice feral deer management guide.

February 2020 update:

All study sites have now been identified, with an additional field research site to assess the effectiveness of aerial shooting of wild deer identified in NSW. This site was selected to conduct mark-recapture distance sampling to estimate abundance of deer, followed by aerial shooting planned for 2020. An assessment of welfare outcomes of aerial shooting of fallow deer will also be conducted.

A final field site for evaluating cost-effectiveness of ground shooting wild deer was established in Tasmania. A grid of remote cameras will be established to estimate fallow deer density, and to understand how it changes following ground shooting by recreational hunters over the next 12 months.

Data analysis from surveys and aerial culling of chital deer on Queensland properties has begun. Detailed analysis comparing species, environments and properties will be conducted.

August 2019 update:

An additional field research site to assess the effectiveness of aerial shooting of wild deer was established in the ACT. The cost effectiveness of aerial shooting for the new site can be estimated and included with other sites from NSW and QLD. Negotiations are underway to assess the effectiveness of aerial shooting at additional sites in SA and NSW.

Welfare outcome assessments of aerial shooting were conducted in the ACT site for Fallow deer and in QLD for Chital deer. Negotiations to assess welfare outcomes of aerial shooting programs in NSW are underway.

Post-control helicopter surveys of a long-term aerial shooting site (treatment and non-treatment areas) in Mudgee, NSW indicate that control has been effective at suppressing the population to a low density. Ground and aerial surveys in north QLD monitoring Chital deer population recovery from control efforts compared with areas without control activities. These surveys give insight into the population dynamics for Chital deer in the dry tropics which impacts control strategies.

Negotiations are underway with Melbourne water to collaborate on an upcoming ground shooting program in their water catchments. A meeting is also scheduled with Tasmanian Land Conservancy to discuss potential sites to evaluate ground shooting.

February 2019 update: 

Field research sites to assess the effectiveness of aerial shooting of wild deer have been established in North Queensland (chital deer), the New South Wales (fallow deer).  

The project team has used helicopter mark-recapture distance sampling to estimate the abundance of deer at the field sites, prior to aerial shooting being conducted. Non-treatment sites were also surveyed using this method in the two New South Wales sites and using a combination of aerial and ground surveys in North Queensland.  

This survey method has provided robust estimates of abundance at acceptable cost. 

The team has assessed the welfare outcomes of aerial shooting of chital deer in North Queensland and have begun to assess the welfare outcomes of ground shooting of rusa deer in New South Wales.  

During aerial shooting operations conducted for chital deer (North Queensland) and fallow deer (New South Wales), and ground shooting operations for rusa deer (New South Wales), blood samples have been collected that are being analysed by Jose Luis Alfredo Huaman Torres (PhD candidate, La Trobe University) as part of the project looking at the role of wild deer in the transmission of diseases of livestock.  

A journal article has been published in PLOSone showing how many animals need to be sampled in assessments of animal welfare outcomes to provide robust estimates of the frequency of adverse events such as wounding during shooting operations. They are using this work to inform our assessments of the welfare outcomes of aerial and ground shooting of deer.  

Reports:

Scientific publications:

  • Forsyth D, Bengsen A, Pople T, Brennan M, Amos M, Leeson M, Gray B, Orgill O and T C (2021) Effectiveness of aerial shooting for controlling wild deer in Australia Proceedings of the 18th Australasian Vertebrate Pest Conference (AWMS 2021 Abstract) https://avpc.net.au/proceedings/
  • Hampton J., Forsyth D and MacKenzie D (2021) ‘Animal welfare assessment of ground shooting for wild Australian deer’, Proceedings of the 18th Australasian Vertebrate Pest Conference https://avpc.net.au/proceedings/
  • (AWMS 2021 Abstract) https://avpc.net.au/proceedings/
  • Bengsen A, Forsyth D, Harris S, Latham A, McLeod S and Pople A (2020) A systematic review of ground-based shooting to control overabundant mammal populations Wildlife Research, 47:197–207. https://www.publish.csiro.au/wr/Fulltext/WR19129?subscribe=false
  • Bengsen AJ, Forsyth DM, Pople AR, Brennan M, Amos M, Leeson M, Cox TE, Gray B, Orgill O, Hampton JO, Crittle T and Haebich K (in press) ‘Effectiveness and costs of helicopter-based shooting of deer’, Wildlife Research. https://www.publish.csiro.au/WR/WR21156
  • Comte S, Thomas E, Bengsen AJ, Bennett A, Davis NE, Brown D and Forsyth DM ‘Cost-effectiveness of volunteer and contract ground-based shooting of sambar deer in Australia’, Wildlife Research. https://www.publish.csiro.au/wr/WR22030
  • Comte S, Thomas E, Bengsen AJ, Bennett A, Davis NE, Freney S, Jackson SM, White M, Forsyth DM and Brown D (in press) ‘Seasonal and daily activity of non-native sambar deer in and around high-elevation peatlands, south-eastern Australia’, Wildlife Research. https://www.publish.csiro.au/WR/WR21147
  • Forsyth DM, Comte S, Davis NE, Bengsen AJ, Côté SD, Hewitt DG, Morellet N and Mysterud A (2022) ‘Methodology matters when estimating deer abundance: A global systematic review and recommendations for improvements’, Journal of Wildlife Management, 86:22207, https://doi.org/10.1002/jwmg.22207.
  • Hampton J, MacKenzie D and Forsyth D (2019) ‘How many to sample? Statistical guidelines for monitoring animal welfare outcomes’, PloS ONE, 14(1):0211417, https://doi.org/10.1371/journal.pone.0211417.
  • Hampton JO, Bengsen AJ, Pople AR, Brennan M, Leeson M and Forsyth DM (2021) ‘Animal welfare outcomes of helicopter-based shooting of deer in Australia’, Wildlife Research, 49:264–273, https://doi.org/10.1071/WR21069.
  • Hampton JO, MacKenzie DI and Forsyth DM (2022) ‘Animal welfare outcomes of professional vehicle-based shooting of peri-urban rusa deer in Australia’, Wildlife Research, https://doi.org/10.1071/WR21131.
  • Wildlife Research, Special Issue: Ecology and Management of Wild Deer in Australia, Volume 50 Number 9 2023. CSIRO Publishing. CSIRO PUBLISHING | Wildlife Research

News articles:

15/05/20 – https://invasives.com.au/news-events/using-ground-based-shooting-successfully-manage-overabundant-pest-animals/

22/07/19 – https://www.abc.net.au/news/2019-07-21/deer-enemy:-frustrated-farmers-at-breaking-point/11334414

Glovebox Guide to Managing Feral Deer