Australia’s original earthmovers and landscape gardeners are missing in action! The decline of mammals, birds and reptiles which dig, burrow, rake through leaf litter and pollinate the bush is depriving Australia’s ecosystems of many of these important functions. Thanks to the conservation and rewilding efforts of Australian Wildlife Conservancy (AWC), not only are rare and declining species being given a chance at recovery – we’re also restoring critical ecological processes to the landscape.
This Biodiversity Month, AWC pays homage to Australia’s ‘ecosystem engineers’ – those species which have an outsized impact on the environments around them and keep our ecosystems in good health.
Many of Australia’s mammal species (including wombats, Echidnas, bettongs, and Bilbies) are serious earthmovers. The Bilby uses its strong front claws to dig beneath the surface searching for insects and their larvae which form part of its diet. The conical pits they dig (usually 10-25cm deep) while feeding have been shown to collect leaf litter, seeds and extra water as runoff, offering an ideal nutrient-rich environment for germination. Apart from tilling the soil in this way, Bilbies also construct extensive burrow systems where they shelter during daylight hours. Over the course of a year, an individual Bilby turns over around 20 tonnes of soil! These temperature-regulated burrows are prime real estate, with smaller animals like hopping mice, mulgaras, and monitor lizards often taking up residence in them too.
Bushfire hazard reduction is an important job, and research conducted on AWC sanctuaries has shown that a brigade of native animals might be our best allies in managing fuel loads. By increasing the turnover of soil and leaf litter, bettongs, Bilbies, Numbats and bandicoots essentially boost the mulching process. AWC scientists compared leaf litter mass inside and outside fenced areas at Yookamurra, Scotia and Karakamia Wildlife Sanctuaries, and found that the reintroduced digging mammals inside fenced areas led to significantly less combustible material on the ground. Separate research found that by scraping up material for their mounds, Malleefowl also reduce fire intensity and create small-scale fire refuges that benefit a range of other plants and animals.
A key part of AWC’s nationwide science program is targeted research to help further the effectiveness of our conservation work and improve our understanding of wildlife and ecosystems.
Soon to be returned to AWC’s Mt Zero-Taravale Wildlife Sanctuary in North Queensland, the Northern Bettong has a sophisticated palate: more than 50% of its diet consists of truffles (the fruiting bodies of underground fungus). It’s been revealed that this fungal network (called mycorrhiza) has a symbiotic relationship with the roots of eucalypts and casuarinas, playing a key role in making nutrients available for uptake. The Northern Bettong is integral to this relationship, dispersing fungal spores and thereby helping plants to access nutrients unlocked by the fungal network. Bringing the bettongs back to Mt Zero-Taravale Wildlife Sanctuary will help restore a healthy, functioning forest ecosystem.
Native animals play important functions above ground level too. At Sydney’s North Head Sanctuary, where AWC is contracted by the Harbour Trust to provide strategic advice on the conservation of this iconic headland, we have reintroduced populations of three small native mammals which are important pollinators of a critically endangered Banksia scrub vegetation community. The Brown Antechinus, Eastern Pygmy Possum, and Bush Rat all include nectar and pollen as part of their diets to some extent, clambering over the sturdy Banksias and inadvertently spreading pollen between flowers as they go. Restoring these mammal pollinators is also a critical part of conserving the flora of the headland.
Effectively conserving Australia’s wildlife is critical work that secures threatened species and prevents extinctions, but it’s also crucial for restoring ecologically healthy landscapes. With your help, AWC is rebuilding populations of these amazing ecosystem engineers around Australia.