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I. Introduction 4. CURRENT PROTECTION MEASURES
In this review, adequate protection is defined as; the provision
of protection measures so that no medium or long term change in
the floristic or faunal composition or structure of rainforest
is likely to result from harvesting and related activities, with
the ultimate aim of protecting the evolutionary potential of rainforest
species. The strategy to achieve these ends may involve higher
relative risks of local losses of some rainforest patches compared
to other, more important patches. Such risks may be acceptable
if they are balanced by the potential for gains in other areas,
and if rainforest values in Victoria are likely to be conserved,
despite these risks.
Tasmanian rainforests harbour 17% of that State's endemic dicotyledons
and gymnosperms (Hill and Read 1987). This contrasts with Victoria
where most of the plant species that comprise rainforests are
capable of persisting within adjacent sclerophyll forests (McMahon
1987, Chesterfield et al. 1990, Cameron 1992). The Victorian
cool temperate rainforest vascular flora is not remarkably rich
(Busby and Brown. in press) and there are few issues of endemic
vascular flora conservation in this rainforest type. Notable
exceptions are Astelia australiana from the Otways and
Central Highlands and Podocarpus lawrencei ssp. nov. (Goonmirk
Rocks) which dominates an unusual and restricted rainforest community
on the Errinundra Plateau. Other rare or vulnerable species that
occur entirely or mostly in cool temperate rainforest include
Cyathea cunninghamii, Lastreopsis hispida, Tmesipteris elongata,
T. ovata and Lycopodium varium (see Gullan et
al. 1990). Non-vascular plants account for the majority of
both a and b-diversity in Victorian rainforests and mixed forests
(Howard and Ashton 1973, Cameron and Turner 1994). However, there
is as yet no distributional database upon which their conservation
status could be evaluated.
There is no complete compilation of information available on animal
species that depend on rainforest for breeding, feeding or migration.
Two species of forest bird and one mammal are primarily dependent
on rainforest in Victoria (W. Peel, R. Loyn, personal communication).
The pink robin (Petroica rodinogaster) uses cool temperate
rainforest for breeding, feeding, roosting and nesting in the
breeding season, although smaller numbers breed in sclerophyll
forest with similar structure. The brown gerygone uses warm temperate
rainforest dominated by Acmena smithii for breeding, and
for feeding, roosting and nesting throughout the year. It also
breeds in sclerophyll forests with abundant vines. The grey-headed
flying fox (Pteropus poliocephalus) roosts and feeds in
warm temperate rainforest trees. The southern barred frog (Mixophyes
balbus) may be restricted to wet forest and warm temperate
rainforest (Hero et al. 1991, Robinson 1993) although there
are only three Victorian records of the species. One threatened
mammal species, Leadbeater's possum (Gymnobelideus leadbeateri),
is strongly associated with old-growth eucalypt forest bordering
mature, cool temperate rainforest (Lindenmayer et al. 1991).
Warm temperate rainforests have considerable value for the conservation
of vascular flora. Cameron (1984) lists 35 plant species mainly
or exclusively restricted to rainforest and rainforest margins
that he considers "at risk" in Victoria. All of these
species are from warm temperate rainforest, and 10 species are
restricted to rainforest margins rather than to the rainforest
interior. A total of 22% of the rare plant species of East Gippsland
occur in rainforest and 18% are restricted to it. CFL (1987)
lists 15 'ecologically important' plant species and 10 vertebrate
species that depend primarily on rainforest. McMahon (1987) highlights
the dangers to epiphytic ferns from repeated fires in rainforest.
The ecology of bryophytes would suggest that they may be susceptible
to repeated fires and to changes in the physical environment following
the creation of a sharp edge, but there are no data to support
this notion.
There is little published information on the ecological significance,
degree of endemism or specialisation, or conservation status of
any Victorian rainforest taxa, apart from incomplete information
on plants and vertebrates and Cameron's (1987) study in which
levels of endemism for plant communities on the Errinundra Plateau
are listed.
Three planning processes relate to the conservation of rainforest
in Victoria. Firstly, the Land Conservation Council (LCC), an
autonomous Government agency, is responsible for making recommendations
to Government on the use of all public land in Victoria. Secondly,
CNR is required to develop a forest management plan for State
Forest within each of the areas of State Forest called Forest
Management Areas (Forest Management Areas). Only the Otways Forest
Management Area plan is complete. However, a number of draft
plans are expected to be released in 1994/95. These plans are
designed to deal with particular issues relevant to an area such
as conservation planning, water production, recreation and wood
production. They include the delineation of General Management,
Special Management, and Special Protection Zones within which
activities are prescribed to manage a given forest value. Thirdly,
in areas from which timber is actually harvested, Wood Utilisation
Plans are developed to meet the requirements of the Code of Forest
Practice for timber production. There is an additional legislated
requirement under the Victorian Flora and Fauna Guarantee Act
(1988) for listed communities, requiring the preparation of anaction statement prescribing management of the community. Cool
temperate rainforest is listed on Schedule 2 of the Act.
Rainforest is considered in all three planning processes. The
major goals of rainforest management are the conservation of communities,
and the maintenance of genetic diversity and the potential for
evolutionary development (CFL 1987), objectives that are consistent
with the use of resources within a context of ecological sustainability.
Guidelines for management of public land adjoining rainforest
were provided by CFL (1987). They include:
These guidelines have been adopted by CNR in the Code of Forest
Practice for timber production (1989). The Code also stipulates
that regeneration practices should attempt to approximate the
composition of the stand prior to harvesting (CFL 1989, p. 9).
The Department has implemented interim measures to defer harvesting
in proposed Sites of National Significance for rainforest and
to extend buffers to a minimum of 40m (Auditor-General 1993, D.
Holmes, pers. comm.). Government policy (CFL 1987) stipulates
that proposed Sites of Significance for rainforest be identified
and accommodated in forest management. In the context of this
report, proposed Sites of Significance for rainforest (Cameron
1982, 1990, Parkes 1990) are specific areas identified by the
Flora Section of CNR as having high conservation status. They
may be defined by other authorities on the basis of their ecological,
scenic, wilderness and recreational values (see AHC and CNR 1994).
The LCC landuse planning procedures have placed many rainforest
stands of higher significance within conservation reserves. CNR's
forest management planning process extends this strategic protection
to rainforest stands within areas designated as State Forest.
The only realistic alternative to prescriptive buffers is to
exclude harvesting from entire subcatchments, using a list of
priorities for sites to exclude the most important of the rainforest
subcatchments, and allow harvesting in the remainder. This procedure
requires two additional steps, namely the development of a priority
list, and a stopping rule. That is, how far down the list should
we harvest?
Forest Management Area plans (DCE 1992, CNR 1994) specify special
protection measures within wood production areas, including subcatchment
protection for highly significant sites, and greater protection
in corridor systems for other sites. All remaining stands are
afforded general protection under the Code of Forest Practice.
The Forest Management Area plan for East Gippsland (CNR 1994)
applies the strategy outlined above, based on three levels of
protection linked to the level of significance assigned to individual
rainforest patches. Protection is provided by conservation reserves
designated by the LCC landuse planning process, Special Protection
Zones providing 100 m or greater buffers within State Forest,
and protection of the balance by the Code of Forest Practices.
The draft Forest Management Area plan for East Gippsland
(CNR 1994) represents the current state of rainforest protection
planning in Victoria. The definition of rainforest adopted by
CNR was used to identify rainforest patches in East Gippsland.
From this, a refined working definition of rainforest was developed
that identified warm temperate and cool temperate rainforest as
vegetation in which the highest proportion of foliage cover comprises
one or more of a set of characteristic species, and which may
include a 'sparse' eucalypt overstorey. Rainforest stands must
be greater than 0.4 ha, or linear strips must be at least 20 m
wide (from edge to edge) and 100m long to be afforded protection,
although some areas with well developed rainforest that are smaller
than the minimum size are protected. In addition, CNR (1994) recommended
that the identification of rainforest in the field depended on
the presence of character species in vegetation that has less
than 50% eucalypt canopy cover. This refined working definition
is more in line with the ecological definitions outlined by Webb
(1968) and Dale et al. (1980). However, the method relies
on the structure and composition of the canopy and does not explicitly
recognise seral communities associated with rainforest or the
floristics of the understorey.
A total of 62 sites were identified in State Forest in East Gippsland
as deserving special protection because of their conservation
value, mostly because they are well developed examples of rainforest
within broader landscape areas. In the Forest Management Area
planning process for East Gippsland, priorities for different
areas were developed first on rainforest values including rarity
and representation using Australian Heritage Commission criteria
(eg., AHC and CNR, 1994), and then on the basis of their size,
the proximity of old-growth sclerophyll forest (as defined by
Woodgate et al. 1994) and the location of subcatchment
or other management boundaries. General guidelines for the development
of priorities are outlined in the draft report by CNR (1993).
In these State Forest areas, sub-catchment based core zones were
identified within Sites of Significance for rainforest and some
were placed in Special Protection Zones. Allocation was made
according to the criteria that the core zones were substantially
undisturbed, that protection helped fulfil other conservation
targets (such as provision of habitat for threatened vertebrates
or conservation of old-growth forest), and that they provided
a geographic spread of rainforest areas with sub-catchment protection
across the Forest Management Area. These processes are consistent
with Government policy for rainforest protection (see CFL, 1987,
p. 14).
In East Gippsland, core areas within proposed Sites of Significance
for rainforest were identified by Departmental Officers from the
Flora Section in close collaboration with Planners. Protection
measures were designed on a case-by-case basis. The Significance
rating of a proposed Site contributed to the planning of protection
measures, as did previous disturbance history within the Site,
the value of timber, practical harvesting constraints, and the
potential for impact of the proposed management activities. The
impact of harvesting was determined by its proximity to the core
area, the topography of the Site, the kind of disturbance anticipated,
the presence of other conservation values including Sooty Owls,
Long-footed Potoroos and Orbost Spiny Crayfish within the Site,
representation of the same values in other protected Sites, and
the silvicultural technique to be implemented.
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