Reef Report for Tuesday, August 2, 2005
Local Scientists Team up to Protect Tropical Rain Forest Wildlife
Local scientists Dr. Miriam Goosem and Mr. Nigel Weston have been honored for their work on conservation of rain forest species by their nomination for the Australian Museumís Eureka Prize. These prizes are awarded for innovative original work in science.
The two scientists research focuses on human impacts on the local tropical rainforests, and on ways these impacts can be reduced.
These local ecosystems are so unique that they have been listed as a World Heritage Site.
The work that has received all this attention has been focused on reducing the impact of roads on wildlife. The tropical rainforests at the mountains behind Cairns have been divided from one huge forest into many smaller ones by highways, farm and logging roads. What immediately comes to mind would be traffic fatalities inflicted upon local wildlife, and losses can be quite significant for some species, even threaten them with extinction. A less noticeable but equally or more important negative effect of roads through forests is habitat fragmentation, which occurs when large blocks of habitat are divided into smaller and smaller blocks by land clearing, forestry, and roads. Westonís and Goosemís work has focused on establishing safe pathways over and under these roads.
For animals that move along the ground a faunal underpass can be an effective way of protecting them from traffic as they travel from the rainforest on one side of the road to the other.
More than just a tunnel under the road, these underpasses have a natural earth floor, and contain logs, rocks and branches that provide cover and protection for smaller animals using the underpass. In this area the underpasses are large, with a passageway over a metre tall, big enough for the cassowary, a very large local flightless bird, to pass through.
A series of three faunal underpasses were established in a local hotspot for wildlife road deaths, where blocks of rain forest were bisected by a major roadway, as a part of a road upgrade project. Dr. Goosemís research both helped in the design stage of these passageways, but also followed up after their construction, to establish which species were using them, and how frequently.
Nigel Watsonís research focused on helping highly specialized tree-dwelling species move between blocks of rainforest. These species of possums, three of them with very limited population numbers and small amounts of suitable habitat, are so adapted to life in the canopy that they will not descend to the ground to cross roads or use faunal underpasses. A road through the forest, however narrow it is or little traffic it gets, becomes a barrier that these animals will not cross. By fragmenting their home range in this way, these species become limited to smaller and smaller patches of habitat, decreasing their population, and increasing the chance of their disappearing from patches of forest.
Mr. Watsonís examined and refined whatís called a canopy bridge, essentially a bridge over the road, connecting these patches of forest. Canopy bridges over roads have been used in small numbers around the world, the first known being in the United States, where the town of Longview, Washington, established a canopy bridge for squirrels across itís main road.
Mr. Weston focused his initial research on a canopy bridge set in local rainforests in 2000, and established the fact that the bridge was being used by arboreal possums to cross from one patch of forest to the other. He also took a careful look at how the animals used the canopy bridge, enabling the design of a canopy bridge that was equally effective, but both less expensive to construct and easier to set in place.
Since that time a number of canopy bridges have been erected across roads in the Cairns highlands, with Mr. Weston working to evaluate their effectiveness.
We hope that the work of these two researchers helps to create a roadway design process that includes connecting using faunal underpasses and canopy bridges, as well as a review of the habitats in the area effected by roads, with the goal of identifying locations for these structures that would have the most beneficial effect.
Our favorite one-day rain forest wildlife tour.
A more detailed profile of Nigel Watsonís research.
A more detailed Profile of Dr. Goosemís research.
More information about the Australian Museumís Eureka Awards.
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who compiles them from the many conversations he has with dive staff in the area, as well as† many other local sources in the dive
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