Cost-effective management of wild deer

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.

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.

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.

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.

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.