Review of Grassland Management in south-eastern ... - Parks Victoria

Parks Victoria Technical Series No. 39
Grassland Management in SE Australia
grazing as a management tool. One of the interesting outcomes of the majority of these
studies is that the maintenance of the existing, or ‘status quo’ management regime of
‘natural’ but degraded systems often leads to the continued gradual decline in habitat quality
and species diversity. It cannot be assumed that ‘status quo’ management leads to
maintaining ‘status quo’ of the system and this idea needs to be challenged given the
abundance of literature that is now emerging on the subject. Current management may be
gradually degrading the system as it has in the past, but at rates which not perceptible at
year-to-year timescales. For example, if adult plants persist under grazing regimes but do not
recruit under those same regimes, it is likely that population declines will occur in time as
adults die out. This difficult and vexing question requires some urgent research and the
quantification of seedling recruitment rates under ‘status quo’ grazing regimes should be a
priority.
For land managers whose primary concern is the conservation of native grasslands, grazing
can only be seen as a short-term tool to maintain biodiversity. It is also a tool that will likely
lead to the gradual degradation of these systems with managers continually gambling on the
level of biomass reduction needed, weather patterns and weed presence. Grazing cannot be
referred to as or used as a biodiversity enhancement tool as implied by some. In fact, most
studies tend to show that if grazing is slightly mismanaged, it can have negative and
sometimes catastrophic effects for biodiversity due to problems associated with selective
grazing, over-grazing and soil degradation.
Selective grazing, particularly of grazing-sensitive forbs, can lead to short-term reductions in
density and longer-term losses in biodiversity, and the loss of food sources and habitat for
native faunal species. Grazing is known to reduce and eliminate taller forbs and shrubs from
grassy ecosystems in south-eastern Australia. Species are often unable to fully recover from
even single grazing episodes. This leads to a reduction in the fitness of an individual and
increases the probability of local species extinction.
3.1.3 Burning
The traditional method of biomass reduction in Kangaroo grass-dominated systems is one of
burning on a regular basis. Investigations of burning of these systems have tended to focus
on intervals of burning in years, and all studies show similar trends. There are many
references in government publications to the possibility of over-burning Kangaroo grassdominated
systems, although all published studies and unpublished data that we have seen
show that the short interval between fires produces positive outcomes for biodiversity of
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