Possums are just the beginning
The natural values of the forest are constantly under threat from a wide range of pest species, from small rodents to feral goats through to invasive plant pests.
Many of our native species, which evolved over the last 60 million years in the absence of ground based mammalian predators, are poorly equipped to deal with these efficient killing machines and vigorous weeds.
Possums can, in high densities, kill large trees by heavy browsing, cause local extinction of threatened plants (such as mistletoe and Dactylanthus), and limit regrowth.
Possums also prey on bird eggs, chicks, and native insects. Possums have been controlled in the park since 1996. Numbers are currently low to moderate.
Magpies and mynahs are known to kill native birds and are aggressive and territorial.
Introduced parrots such as Eastern Rosellas, lorikeets and budgies compete with native birds for the same seed sources, as well as carrying potentially damaging diseases.
Plant Pests are found throughout the forest especially on the fringes.
Climbing vines such as Japanese honeysuckle grow quickly, smothering tall trees. Other weeds such as tradescantia form dense mats cutting out all light and stopping the growth of native seedlings.
Some introduced trees, like pines and privet, grow vigorously and can change the forest makeup. Gorse, pampas and buddleia quickly invade eroded areas and slips, preventing native species from restablishing.
Other threats to forest health include fire and livestock encroachment from surrounding land.