Brush Tailed Rock Wallaby – Predator monitoring and management

This project aims to improve the trajectory of the only known extant population of southern Brush-tailed Rock-wallabies (sBTRW) in Victoria. Which live in the remote Little River Gorge in the Snowy River National Park.

There has been no targeted monitoring of predators in the sBTRW’s habitat so it is currently unknown how to implement the best predator control to increase the population.

 

This project will achieve this by:

1. Establishing a targeted predator camera-motoring program in the habitat of the sBTRW

2. Using this new knowledge to target fox-baiting and cat-trapping

3. Repeat activity one to evaluate predator abundance

4. Confirm correlative success by checking increases in the sBTRW population.

The project is being delivered by East Gippsland Conservation Management Network (EGCMN) for the Environment Restoration Fund-threatened Species Strategy Action Plan-Priority Species grant in partnership with Parks Victoria and DELWP.

Measuring Success of Project Activities
The impact of the project activities will be monitored and measured in the following ways:
1. An increase in the number of sBTRWs recruited the following year and surviving after the pilot cat control and targeted fox control. This will be evaluated from the annual autumn sBTRW targeted camera monitoring and the additional spring sBTRW camera monitoring of females and joeys. This data can be compared with 2023 and previous years assess recruitment and  mortality.


2. A difference in predator abundance and individuals from the two targeted predator monitoring cameras before and after targeted control. This is important as bait takes and trapped cats do not necessarily equate to success if they are quickly replaced by other individuals.

3. The number of cats caught in cage traps and fox takes on bait stations as a form of partial success.

 

WHY?

Predation by the red fox is believed to be the main contributing factor to the decline of the sBTRW. Fox baiting around the gorge assists control of foxes in the gorge however it is possible that differences in home range
shape may lead to foxes in the gorge that are not exposed to baits but are a higher threat to the sBTRW. Cats are seen on sBTRW monitoring cameras 7 X more than foxes. They also inhabit the same rocky dens the sBTRW
use. Offspring of the sBTRW is a little smaller than a rabbit, regular prey for cats. Living side by side it is expected cats would have many chances to predate the offspring once they start emerging from the pouch. This has
become a major concern for the East Gippsland EG Field Team who had cameras that caught 15 pouch emerging offspring in 2020 but camera monitoring and trapping in autumn 2021 could not detect any of the young.