Our Autumn-Winter surveys of the Strathbogie State Forest have begun.
What role does the Strathbogie State Forest play in conservation of native wildlife in the Ranges?
That’s the question we’re addressing with our forest surveys. The techniques we are using are: spotlighting for nocturnal, arboreal mammals; using camera traps (aka trail cameras) to monitor ground-dwelling animals; surveying the forest for hollow-bearing trees. The methods being used are described below and detailed here.
Nocturnal, arboreal animals
There are ten or so species of nocturnal, tree-dwelling mammal that have been recorded in the Strathbogie State Forest. From heaviest to lightest these are: Koala, Mountain Brushtail Possum, Common Brushtail Possum, Ringtail Possum, Greater Glider, Yellow-bellied Glider, Brush-tailed Phascogale, Sugar Glider, Eastern Pygmy-possum, Feather-tail Glider. See Mammal list of the Strathbogie Ranges.
The species we are particularly interested in are the two large gliding possums, Greater Glider, Yellow-bellied Glider and Koala. The Greater Glider has recently been listed as vulnerable to extinction by both the National and Victorian governments. It appears to occur widely in the Ranges, both in forest blocks and in linear strips (roadside and streamside vegetation), as long as there are plenty of trees with big enough hollows for them to den in. But just how secure is this species, given it has begun to disappear from so many other forests in south eastern Australia?
The Yellow-bellied Glider is also a large gliding possum that relies on forests with big, old trees. Like the Greater Glider, its populations in many parts of the state have begun to decline, though no one really understands how it’s faring across its range. This species is thought to have recently disappeared from the Strathbogie Ranges, though there’s still some hope that it survives in a wet, inaccessible gully somewhere. More information about their distribution and abundance is required.
Koalas are a high profile species throughout the Strathbogie Ranges. They are the most easily detected of all arboreal mammals and are often encountered. However, the status of Koalas in the Strathbogies is not easily determined; their numbers are easily over-estimated, where they are seen is not necessarily high quality habitat and the remnant forest in paddocks and along roadsides and streams in the agricultural zone (where the public often sees them), is a high-risk environment for them.
As well as nocturnal mammals, we are interested in the parts of the forest that are home to Powerful Owls. Powerful Owls nest in tree hollows and only the very largest trees would have suitable sized hollows for nesting. They take a variety of prey (birds and mammals), but one of their favoured prey items is the Greater Glider. Powerful Owls are threatened in Victoria.
This relatively new technology is now readily available and affordable for mass-use by citizen science surveys. We have already used camera traps to survey areas of forest in recent years. We can now extend the areas surveyed and collect significantly more information about the cryptic creatures that live on the forest floor.
Our focus will be on several species that are either shy and difficult to detect, or whose presence/distribution in the Strathbogie State Forest is poorly understood: Long-nosed Bandicoot, Deer (Sambar and Fallow), Spot-tailed Quoll (presumed extinct, but …), Brush-tailed Phascogale.
Big, old trees play a critical role in the ecology of forests, but are becoming increasingly rare in Victoria, including here in the Strathbogie Ranges. In the absence of more detailed biodiversity information, hollow-bearing trees are also an indicator of where high-conservation value forest still occurs.
These old-growth giants flower more regularly than younger trees and in-so-doing reliably produce more nectar and pollen for the myriad of animals that rely on these resources. They monopolize soil nutrients and water in times of stress and can suppress the growth of tree seedlings and shrubs, creating a more open understorey. They form hollows of various sizes needed by the dozens of species of animals for survival and breeding.
Trees with hollows big enough for Greater Gliders and Yellow-bellied Gliders may take 100+ years to grow. Old-growth trees with multiple hollows and big enough hollows for Powerful Owl nests could take 200+ years to develop. The way we manage our forests has a significant impact on the survival of hollow-bearing trees and we desperately need a better understanding of the consequences of that management.
Below is a slide-show of the sorts of trees and their hollows that our surveys are targeting.
These surveys are being part-funded by the Victorian Government through a Community Volunteer Action Grant. All funded activities involve engaging local communities and collecting biodiversity data to assist management of the Strathbogie State Forest. All project activities and all project results will be published on this website. Posts relating to this project will be identified with this message:
This is a Strathbogie Ranges CMN project and supported by the Victorian Government.