Biology Reference
In-Depth Information
the content of the outcrop, such as patch size and habitat complexity
●
the condition of the outcrop, such as the level of disturbance and weediness
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the context of the outcrop, including topographical position and surrounding
land use.
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Below we discuss each of these three attributes in more detail.
Outcrop content
Outcrop content includes attributes such as size and habitat complexity. More
reptile species occur as the size of an outcrop increases (Figure 5.8). A small
outcrop covering a few square metres will usually support one or two species of
reptile.
1
Outcrops of about 10 square metres in size can support approximately six
species and large outcrops over 100 square metres can support more than a dozen
species, including large pythons.
2
This relationship between outcrop size and
reptile species diversity is due to the availability of additional kinds of habitats and
extra space to accommodate more species. Large reptiles such as the Inland Carpet
Python and Lace Monitor have home ranges that exceed 10-20 hectares. Outcrops
less than 10 square metres are unlikely to support
viable populations of these predators unless they are
surrounded by large amounts of remnant vegetation.
Structural complexity can influence the number
and type of animals found on an outcrop. This
relates to the amount of different types of habitat
that are formed as boulder stacks increase in height.
Large rocky outcrops support
more species of reptiles than
small ones, but small outcrops
are nevertheless important
environmental and conservation
assets on farms
Outcrop patch size (ha)
Figure 5.8:
The relationship between reptile species richness and granite outcrop patch size in the South
West Slopes of New South Wales.
