- Corridors of planted rainforest trees — landscape linkages — are a straightforward, but costly, on-ground action that can repair past damage and bolster ecosystem resilience in Australia’s Wet Tropics region.
- In the Atherton Tablelands wildlife corridors, now in their third decade, the diversity of naturally regenerating plant species has increased, with trees, vines, rattans, shrubs, palms, ferns and orchids colonizing the planted sites.
- The corridors are providing connectivity and additional habitat for a range of rainforest wildlife, including some threatened by climate change.
- To thoroughly measure the biodiversity outcomes of the linkages, monitoring would need to be more regular, and target a broader range of taxa.
The tooth-billed bowerbird gave itself away with a not-quite-right call. Suspicious, I’d panned my binoculars toward the sound and there he was, the mimic, high in the canopy of a rainforest tree. It was a satisfying sight.
Like many of Australia’s wet tropics-endemic species, tooth-billed bowerbird populations have declined rapidly in recent years, their climate change-induced retreat to higher elevations acknowledged in Birdlife Australia’s new Action Plan for Australian birds.
It was not just seeing this charismatic bird that was so satisfying, however, but where it appeared. It wasn’t found in a survey in a large expanse of World Heritage-listed rainforest. Or even in remnant forest surrounding the Atherton Tablelands’ famous Crater Lakes.
It was in a 25-year-old rainforest restoration site in Donaghy’s Corridor, a 1-kilometer (0.6-mile) linkage of planted habitat.
The tooth-billed bowerbird shows that the linkage is working, at least for some species.
A tooth-billed bowerbird was seen in a 25-year-old rainforest restoration site in Donaghy’s Corridor. Image courtesy of Amanda Freeman.
Landscape linkages: ‘Acts of faith’
Stretching hundreds of kilometers along Australia’s northeast Queensland coast, the Wet Tropics includes nearly 800,000 hectares (2 million acres) of World Heritage-listed tropical rainforest and is one of the country’s most biodiverse regions.
Donaghy’s Corridor, the Peterson Creek wildlife corridor and the Lakes Corridor are a network of rebuilt forest linkages joining the otherwise isolated Lake Eacham, Lake Barrine and Curtain Fig national parks, each 300-500 hectares (700-1200 acres), to Wooroonooran National Park. At nearly 80,000 hectares (200,000 acres), Wooroonooran is one of the largest continuous forest blocks in the Wet Tropics World Heritage Area.
Located near the small town of Yungaburra, on the Atherton Tablelands, the three habitat linkages were “acts of faith” when they got underway in the 1990s. They were a response to past land clearing and forest fragmentation, but nobody had proof they would assist wildlife.
By the 1990s, metapopulation theory was beginning to influence conservation management. The theory implied that restoring habitat and reconnecting forest fragments would reestablish movement and gene flow between species’ populations and maintain biodiversity. But when Donaghy’s Corridor began in 1995, it was largely untested.
“I guess all I was really thinking about was joining up an isolated reserve with a continuous forest,” said Nigel Tucker, director of environmental consultancy Biotropica Australia.
It was Tucker, then manager of the Queensland Parks and Wildlife Service’s (QPWS) Lake Eacham Nursery, who approached the Donaghy family about planting a wildlife corridor on their land, and mobilized QPWS …….