May 02, 2022
Return of the Native Animals
In operation since 1992, the fauna monitoring program at our Huntly and Willowdale mines in Western Australia is helping our experts and the industry better understand the return of forest fauna throughout the different stages of mine rehabilitation.
We are currently monitoring sites within unmined forest, unmined stream zones and rehabilitation sites that are five, 10 and 15 years old. This allows us to confirm that suitable habitat develops over time in rehabilitation areas to achieve animal species diversity and numbers that are similar to the surrounding jarrah forest.
Our experts conduct the surveys each year, alternating between the two mines. Since different species are more active at varying times of the year, we conduct the survey for six to eight weeks in both winter and summer.
The survey involves trapping, identifying, recording and quickly releasing the animals. Humane cage traps are used for larger mammals, cameras capture shy species, and a drift fence guides small mammals, frogs and invertebrates like spiders into a trap. A dot of paint or a small patch of trimmed fur helps ensure captured animals are counted only once.
The 2021 winter survey at the Willowdale mine recorded nearly 180 animals representing more than 30 species. These included two listed threatened species (chuditch and quokka) and two priority conservation species (southern brown bandicoot and western brush wallaby). A special find was trapdoor spiders, which have a lifespan of more than 40 years. These protected spiders live within a very localized area and are susceptible to disturbance, so their presence is a good indicator of rehabilitation success.
We use the survey results to make improvements to our rehabilitation program, such as returning hollowed-out logs to provide habitat for various animals like the chuditch. The results also have demonstrated that mining is a temporary disturbance, with several faunal groups returning to the rehabilitated areas within a relatively short timeframe.