Biology Reference
In-Depth Information
minimise plant invasions. This might mean placing restrictions on the types of
plants that can be grown in areas adjacent to bushland, a challenge urban planners
should consider when new developments are proposed. Broad-leaved weeds
compete with native forbs for space and nutrients and have the potential to reduce
native invertebrates and foraging areas for reptiles and woodland birds. Both
ecological fire regimes and the grazing methods which we mentioned above may
be useful management tools in controlling these kinds of invasive species.
Reducing nutrient levels by restricting the use of super-phosphate also can help
reduce broad-leaved weeds.
Pest animal control
The Red Fox and the Feral Cat are significant predators of Australian wildlife. They
prey on a wide variety of native animals including native mice, small marsupials,
and reptiles. Predation of native animals inhabiting rocky outcrops can be
substantial and may eventually lead to localised extinctions. As an example, the
Inland Carpet Python is a species that breeds every three years in southern New
South Wales and occurs in low population densities. It has declined considerably in
recent years due to habitat loss as well as predation by the Red Fox.
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Fox control
programs with the most significant positive effects on wildlife populations are those
conducted regularly across several adjoining properties (see Chapter 7).
The European Rabbit can have a significant effect on the distribution and
abundance of rock-dwelling flora and fauna by reducing vegetation cover and
promoting soil erosion. This introduced species can reach high population
densities on rock outcrops where it can be extremely difficult to eradicate. One
method traditionally used to reduce rabbit populations was to block the entrances
of rock crevices and cavities with wire-mesh. But this method proved ineffective as
rabbits simply found alternative places to dig their burrows. Today, quite a few
granite outcrops still contain the remnants of wire-mesh. It should be removed to
prevent injury to native animals, particularly those species that regularly use rock
crevices like the Carpet Python. Rabbit control in areas with granite outcrops
requires strategic population control methods (see Box 5.3).
The introduced Portuguese Millipede is a common pest invertebrate found
beneath surface rocks on granite outcrops. A study in the Warby Ranges National
Park near Wangaratta found that millipedes had a significant negative effect on
rock-inhabiting mosses and lichens.
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A reduction in these plants can lead to
increased water runoff and excessive soil erosion. The Portuguese Millipede is
thought to be increasing in abundance and distribution, but the full impact of
this species is still unknown. Further research and monitoring is needed to
determine the impacts of this species on rock-dwelling fauna, and to guide
effective control methods.
