Feral pigs & deer in the Otways

Feral pigs in the Otways

Feral pigs have been sighted in the Otways for decades; however, since 2017, a marked increase in feral pig activity had been observed, including both sightings and damage to farms and public land. The presence of feral pigs in the Otways poses a real threat to these ecosystems and the threatened species that called the Otways home. However, as they were an emerging threat, we didn’t have a good understanding of how widespread they were, and how they were using the ecosystems in the Otways.

In 2018, the Conservation Ecology Centre began working with Parks Victoria on a monitoring and control program  as reported here, and with funding secured through the Wild Otway Initiative in 2020, we were able to expand this work.

Gaining a better understanding of how feral pigs use the Otways

We used GPS collars to better understand feral pig movements and how they used the landscape. In 2021, we began collecting data from GPS collars fitted to feral pigs. Detailed movement data was collected over a series of months, yielding fascinating results that informed our ecological understanding and land management strategies. We have collared a total of eleven pigs across the Otways. 

Through the use of these GPS collars, we confirmed very different behaviour between the boars and sows, observing that mobs of sows tended to remain in one location, while boars travelled much further across the landscape, in some instances up to 25 km per day. The results from this project have been presented at multiple conferences, including the Otways Ecological Research Forum. You can view recordings of these presentations on the CEC YouTube channel. The program has also been featured on ABC’s Landline which you can view here.

In addition to the collars, we deployed replicated grids of monitoring cameras at multiple different locations across the Otways. The data from these camera grids provided us with information about how pigs are spread across the landscape, to study population dynamics and determine the effectiveness of our management. From these grids we were also able to identify individual pigs, allowing us to determine how many were in the landscape. We also collected additional data on the locations where feral pigs occurred via environmental DNA sampling in selected waterways.

Finally, we encouraged the community to report pig sightings and damage via the FeralScan app, which provided us with important information about the types of habitat pigs were using, as well as where pigs were located.

Feral deer in the Otways

Unlike feral pigs, which are an emerging pest, feral deer populations are quite well established in the Otways and deer cause significant destruction to native vegetation, waterways and the habitat of many threatened species. Red Deer are common in the central wet forests, and Fallow Deer tended to occur in the east and west, which are predominantly drier landscapes. During the monitoring undertaken as part of the Wild Otways Initiative, the Conservation Ecology Centre received reports of both Hog and Sambar Deer in the Otways – a first in the region.

Our main focus in this project was developing ongoing and sustainable ways of managing the number of deer in the Otways to minimise the impact on native ecosystems.

Controlling feral pigs in the Otways

Pigs are fast breeders and a sow can have 20 piglets in a year, so if there were 10 sows in a group that means 200 additional pigs being added to a population per year. Therefore making management at a landscape scale essential, whilst highlighting the importance of getting on top of the issue quickly and being consistent.

Rather than elimination across the entirety of the region, we focused on asset protection around our main priority in this work—whether that was of pasture and productive farmland, or our natural assets like water courses, cultural heritage and threatened species or ecosystems.

As part of the Wild Otways Initiative, the Conservation Ecology Centre worked with Parks Victoria, DELWP, Landcare, and private landholders to control feral pigs across the Otways – a patchwork of different land uses. The project involved the use of the HogEye Remote Camera Trap system, sodium nitrite HogGone feral pig baits in remote bait stations and ground shooting.

Parks Victoria staff maintained a number of feral pig monitoring sites within the National Park, and we worked closely with them providing further training and support as we progressed towards control. Several new control sites had also been identified in the Eastern Otways after reports from FFM Vic staff, and we held briefing sessions for those further afield (e.g., East Gippsland) to share learnings.

This multi-faceted approach, which included community education and close working relationships between multiple stakeholders, is a great model that could be applied elsewhere across the state and country.

Engaging the community in feral pest control

Community engagement had been identified early on as crucial to the success of feral pig and deer control in the Otways. We were interested in ensuring the community was informed about the threats these feral animals posed to our unique ecosystems, but also empowered to identify and report sightings. This had been facilitated by the active promotion of the FeralScan app and by us encouraging the community to use it to report pig and deer sightings, damage and sign.

Additionally, due to the high proportion of private land in the Otways, there were also many landowners in the community whom we wanted to engage with directly, to provide them with the knowledge, skills, and contacts they needed to effectively control these pest animals on their land.

We noticed feral pigs preferred areas with open paddocks next to forested areas, which they used for cover. They loved to dig up pasture and in the Otways, we found them coming onto farmers’ pastures over the winter months when the ground was soft and the pigs could dig up invertebrates and other resources available in these paddocks. In summer, they tended to stick more to the forests. Therefore, we really noticed the reports of pig damage from landholders increasing over winter.

Receiving notifications about pig activity from the community and other stakeholders via FeralScan, paired with the detailed insights we were collecting from the cameras and collars, put us in a much better position to successfully manage these pests. FeralScan reports continued to be entered by landholders and community members, and community engagement sessions were being facilitated through the local Landcare networks—the Southern Otway Landcare Network, Central Otway Landcare Network, and Upper Barwon Landcare Network.

This information was already improving management techniques and taking effect on the ground.

Collaborations with field game harvesters

The control of deer in the Otways was likely to be an ongoing activity and as such needed to be sustainable from practical and economic standpoint, as well as an environmental perspective. As part of the Wild Otways Initiative, the Conservation Ecology Centre facilitated engagement between Wild Game Field Harvesters (WGFH) and landholders in the Southern Otways to increase deer control on private land. The hope was that we could turn local venison into a commercially viable product as a way of facilitating the ongoing control of deer in the Otways.

A WGFH had begun harvesting deer across private properties in the Southern Otways after engagement took place between the Conservation Ecology Centre, landholders and the WGFH. We continued to engage with local hunters and WGFH to encourage uptake of WGFH qualifications and improve deer control on private properties. One local hunter, whom we engaged with in July, had gone on to trap 20 feral pigs, enrol in his WGFH course, and since completed it, carrying out further work across the landscape.

Another two WGFHs were now set up to start harvesting deer in the new year. We passed their details onto Landcare Networks, to pass onto their members. We also planned on linking them in with multiple landholders in the same area to help improve the effectiveness of their control across the landscape.