Improving the effectiveness of baiting strategies on foxes and feral cats at Gnaraloo Station over the past 10 years has provided complete protection of marine turtle nests.
Marine turtle nests can be severely predated by foxes and other introduced predators.
Director of Animal Pest Management Services Mike Butcher conducted control and monitoring of foxes, wild dogs and feral cats, their occupancy rates and the predation levels on marine turtle nests and hatchlings from June 2017 through to June 2018.
The adaptive management program was run in conjunction with the Gnaraloo Wilderness Foundation & Gnaraloo Turtle Conservation Program and was supported by Rangelands NRM through funding from the Australian Government’s National Landcare Program.
Adaptive management improves the program by allowing rapid changes to methods based on data and knowledge collected.
“We conducted trapping, baiting and shooting programs to reduce predation of turtle nests,” he said.
They then assessed the effectiveness of standard 1080 baiting of foxes against feral cats.
“We wanted to know whether baiting of foxes can also reduce feral cat numbers that may increase by removing the top-order predators.”
“This was to ensure that while protecting one animal, we were not having a negative effect on others.”
Mike found that bait selection and timing can also significantly reduce feral cat numbers.
He said the control programs need to be targeted to be effective both in the short and long term.
“Baiting strategies need to take into consideration that once foxes are depredating high protein foods that are readily available, such as marine turtle nests, bait quality and the location of baits is critical for success,” he said.
From this work, one hundred per cent protection from predation was achieved for seven consecutive seasons.
“Only five fox detections occurred on 70,000 hectares during the past six years and these were a result of new incursions,” he said.
When the first program started, Mike said predation of marine turtle nests was between 80% and 100% nightly.
“Previous programs in WA had only achieved protection of marine turtle nests of about 3% predation, but these assessments only measured predation in the first night the nest was laid,” he said.
“We have conducted the programs using experience and adaptive management techniques to demonstrate that 100% protection of marine turtles from predation can be achieved,” Mike said.