Phytophthora Dieback Reduces Habitat Quality for Quendas in Western Australia

A recent study conducted by Murdoch University has highlighted the detrimental effects of Phytophthora dieback on quendas, a native digging mammal, in Western Australia's jarrah forests. The research, published in Austral Ecology, indicates that the disease is indirectly affecting quendas by reducing the quality of their habitat, which in turn decreases their digging activity.

Phytophthora dieback, an introduced plant disease, has been known to impact native plant communities significantly. One of the most affected species is the Australian grasstree, which provides essential shelter and habitat for various native animals. The study found that in areas infested with dieback, there was a 46% reduction in low shrub cover, 45% fewer habitable grasstrees, and 40% more bare ground compared to healthy forests.

The research team, led by Dr. Tom Mansfield, conducted a yearlong field study in the Shire of Mundaring, east of Perth. They observed that quenda digging activity was 33% lower in dieback-infested areas. Despite this, quendas still entered these areas to dig, suggesting they might use surviving grasstrees and shrubs as habitat. The study also noted that while food resources like fungi were not conclusively reduced, the lack of dense vegetation might expose quendas to predators, reducing their foraging time.

Quendas play a crucial role as ecosystem engineers, with their digging activities aiding soil turnover, water infiltration, and seed and fungi distribution. The reduction in their activity due to habitat degradation could have cascading effects on the ecosystem. Dr. Mansfield emphasized the importance of habitat restoration, particularly through the protection of surviving grasstrees and the introduction of artificial refuges, to support quenda populations.

The findings offer practical guidance for managing dieback and restoring habitats. Local initiatives, such as revegetation and fauna-friendly gardens, could mitigate the negative impacts of dieback on quendas. Dr. Mansfield also highlighted the need to identify dieback-resistant plants and prevent further disease spread to maintain healthy ecosystems.