Informing Biodiversity Conservation for the Adelaide and Mount

146 Pages·2010·3.66 MB·English

Informing Biodiversity Conservation for the
Adelaide and Mount Lofty Ranges Region
South Australia
PRIORItIES, StRAtEGIES ANd tARGEtS
HERO IMAGE - ONE IMAGE ONLY NO COLLAGES
June 2010
Department
for Environment
and Heritage
www.environment.sa.gov.au
Acknowledgements
The Department for Environment and Heritage coordinated the preparation of this document.
It is the culmination of several years project work, representing contributions from numerous
individuals, agencies and other organisations.
The Department would like to acknowledge the many people and organisations who
contributed to the development of this report.
Early drafts were compiled by Monique Blason and Sandy Carruthers. The primary author of
the current version of the strategy is Lisa Farroway. Significant contributions to the finalisation
of this version were made by Andrew Willson and Beatrice Hurrell.
The preparation of this report would not have been possible without the efforts and support
of various steering committee members including Wendy Stubbs, Brenton Grear, Jody Gates,
Andrew West, Adrian Stokes, Chris Morony and Ben Moulton.
Other individuals who provide valuable expertise are Amelia Hurren, Julia Bignall, Ben Fee,
Glen Sholtz and staff of DEH’s Adelaide Region Biodiversity Conservation Unit.
All information in this report was correct at the time of printing.
Except where otherwise indicated, all figures and photographs have been provided by the
Department for Environment and Heritage.
Cover photo - silky tea tree (Leptospermum lanigerum) swamp and candle bark forest
(Eucalyptus dalrympleana ssp. dalrympleana), Sinclair’s Gully, Norton Summit. Photo by Sonia Croft.
Citation: DEH (2009) Informing Biodiversity Conservation for the Adelaide and Mount Lofty Ranges Region,
South Australia. Priorities, Strategies and Targets.
© Department for Environment and Heritage
Produced by the Corporate Communications Branch
All rights reserved
June 2010 FIS 90346
ISBN 978-1-921466-36-6
Contents
PARt 1 I ntroduction 1
1.1 Purpose and scope 1
1.2 Region description 4
PARt 2 Biodiversity State and condition 7
2.1 What the region previously looked like 8
2.2 What the region currently looks like 9
PARt 3 Approaches and framework for conservation 16
3.1 Impacts of modification and landscape change on biodiversity 16
3.2 Conservation planning principles 17
PARt 4 C onservation of biodiversity 23
4.1 Conservation of terrestrial and coastal biodiversity 23
4.1.1 Conservation of landscapes 26
Fragmented high cover landscapes 28
Disproportionately cleared fragmented landscapes 30
Recently fragmented landscapes 34
Presumed fragmented landscapes 37
Fragmented coastal landscapes 40
Relictual landscapes 44
4.1.2 Conservation of ecological communities 47
Conservation targets for ecological communities 52
Heathy forest 55
Heathy woodland 57
Shrubland 60
Grassy woodlands 62
Grassland 66
Mallee 68
Riparian 71
Wetland 75
Coastal vegetation 77
4.1.3 Conservation of species 90
Threatened species 90
Declining species 95
Endemic species 96
Abundant native species and native species in conflict 98
4.1.4 Aquatic ecosystem conservation programs 103
4.2 Mitigation of threatening processes 109
PARt 5 Stakeholders 114
PARt 6 Improving planning integration, application and knowledge 118
PARt 7 References and further reading 119
PARt 8 Appendices 131
PARt 1
Introduction
This part outlines what this report aims to achieve, and includes
a regional description.
1.1 Purpose and scope
Informing biodiversity conservation in the region
In South Australia, the Adelaide and Mount Lofty Ranges (AMLR) region is unique – relatively high
rainfall, hilly topography and surrounded west and south by coastal environments. The diversity of
landscapes within a comparatively small area supports a diverse array of ecosystems and species.
Many species are endemic to the region or geographically separated from other State or interstate
populations. The region is also home to over one million people residing in both urban and rural
areas. The environmental health of the region is therefore important for both quality of life and
economic prosperity.
However, historic native vegetation clearance has been significant and only approximately 13% of
original native vegetation remains in the region. Species have become extinct and many more are
continuing to decline.
Biodiversity conservation in the AMLR region aims to maintain, restore and halt the decline in
ecological processes, vegetation communities and species. However, there is a limited amount
of funding and resources available for biodiversity management, with an increasing level of
accountability to ensure public funds are wisely spent. There is a need, therefore, to prioritise and
ensure that works are targeted to meet specific and achievable outcomes.
This report aims to inform existing regional biodiversity programs and funding bodies about
conservation priorities, and proposes strategies and targets to achieve effective management of
these priorities. It does this by assessing the current biodiversity status of the region (mainly through
an analysis of vegetation decline) using current landscape planning principles, and by linking with
other relevant regional planning processes.
Conservation targets and actions are set at a variety of biological and spatial scales. There are
high-level targets for managing landscapes as a whole, combined with targets for managing
specific ecological communities, and targets related to conserving threatened species and other
species that require conservation efforts. While many strategies and targets developed in this
document are ambitious and require significant levels of additional resources to implement, others
can be achieved with existing resources through improved information sharing, planning and
regulatory processes.
This report also provides a framework with which to develop conservation management priorities.
However, it is acknowledged that ‘one document cannot do all’ and there are challenges ahead
to develop a fully integrated planning framework which can drive relevant regional biodiversity
management at a variety of biological and spatial scales (and which is relevant to State and
National conservation goals).
This document and the underlying analysis is intended to be dynamic, to change with new
knowledge, new data and changing conditions. As mapping data is improved and new information
becomes available from research and monitoring activities, strategies and targets should be
modified.
1 Informing Biodiversity Conservation for the Adelaide and Mount Lofty Ranges Region, South Australia
Links to planning processes
AMLR NRM Plan
Outputs during the development of this report were used in formulating key biodiversity targets
in the AMLR Natural Resource Management Board’s plan Creating a Sustainable Future – An
Integrated Natural Resources Management Plan for the Adelaide and Mount Lofty Ranges Region.
The Department for Environment and Heritage (Adelaide Region) is currently implementing several
NRM threatened species and vegetation management programs, the direction of which have been
guided by this integrated planning approach.
South Australia’s Strategic Plan and No Species Loss
South Australia’s Strategic Plan (SASP) details a series of targets that provide a path towards a
prosperous and better future for South Australia. The plan includes targets relating to increasing
economic growth, including expansion of mineral exploration and production, and increasing the
population of South Australia. There are also environmental targets, including a target to lose no
known native species as a result of human impact. This target is addressed through No Species Loss
– A Nature Conservation Strategy for South Australia 2007-2017, the implementation of which will be
assisted by this report for the AMLR region.
NatureLinks
Another SASP target involves the development of five ‘NatureLinks’ biodiversity regions across
the State. This report will help deliver the NatureLinks goal of integrated ecosystem management
across the landscape. Regionally, the Cape Borda to Barossa NatureLink Strategy will facilitate the
implementation of many priorities proposed in this report through assessing key challenges facing
landscape scale conservation initiatives and progressing solutions to these challenges.
Photo: © DEH
Informing Biodiversity Conservation for the Adelaide and Mount Lofty Ranges Region, South Australia 2
the Plan for Greater Adelaide (2009-2038)
This plan guides how the state government proposes to balance population and economic growth
with the need to preserve the environment and protect the heritage, history and character of
the greater Adelaide region. The policies in this plan will have an important influence on statutory
planning processes in relation to increasing the consideration of biodiversity in development
planning processes. The implementation of these policies will rely heavily on priority-setting
information such as that contained within this report.
Regional Recovery Pilot Project
This report and the Regional Recovery Plan for Threatened Species and Ecological Communities of
Adelaide and the Mount Lofty Ranges, South Australia were prepared concurrently and are closely
integrated. Successful implementation of both species management requirements and habitat
reconstruction targets are dependent on each other.Legislative context
Legislative context
The content in this report is guided by, and informs, legislation and policy. Appendix 1.1. lists core
or primary relevance documents which drive or provide immediate and direct obligations and
expectations on Australia and South Australia in biodiversity conservation and management.
Partial or secondary relevance documents influence or provide more indirect obligations, mainly
by promoting principles of ecologically sustainable development. In particular, it is hoped that this
report may assist in the strategic operation of some elements of the Native Vegetation Act, such as
the Significant Environmental Benefits scheme.
Conserving biodiversity will require partnerships and co-ordinated efforts
Conserving the native plants, animals and ecosystems of the AMLR will be a challenging task.
Multiple and diverse conservation efforts will be required, across large spatial and temporal scales.
Meeting this challenging task, and minimising the loss of native species from the region, will require
partnerships between Government, non-government organisations, industry, scientists, indigenous
peoples and community groups.
What does this report NOt do?
Marine biodiversity has not been covered by this report, to avoid duplication with separate marine
specific planning processes. Marine Plans are being developed on a bioregional basis for all State
waters, guided by the Marine Planning Framework for South Australia, with links to regional NRM
Planning. Note that planning processes that are addressing biodiversity requirements for marine
environments are included in Appendix 1.1.
This report does not propose species-specific management, or use concepts of species-based
surrogacy for management (such as umbrella, flagship, indicator or keystone concepts).
It is not intended that this report acts as a ‘resource-inventory’ document. While a variety of
summary statistics and lists are presented for biodiversity, other documents and planning tools exist
in the region which can present more detailed information.
The emphasis of this report is the provision of ecological targets based on a regional landscape
analysis. The report does not attempt to propose detailed strategies for management processes
which mainly act at the broader State or National level (such as climate change policy).
3 Informing Biodiversity Conservation for the Adelaide and Mount Lofty Ranges Region, South Australia
1.2 Region description
The Adelaide and Mount Lofty Ranges region, as defined for this report, covers a total area of
780,000 ha, or 780 km2. The region includes metropolitan Adelaide, Willunga Basin, the Mount Lofty
Ranges (including the foothills, hills-face and eastern flanks), the Fleurieu Peninsula, the northern
Adelaide plains to the Light River, and the Barossa Valley. The region includes approximately 263
km of coastline, being bounded on the west by Gulf St Vincent, and on the south by the Southern
Ocean. The planning region does not include marine waters generally below the high tide mark.
Most of the planning region defined for this report falls within the Adelaide and Mount Lofty Ranges
Natural Resources Management (NRM) region. The eastern flanks of the region fall within the South
Australian Murray Darling Basin (MDB) region (Figure 1.1)
Figure 1.1: The planning region used in this report
Informing Biodiversity Conservation for the Adelaide and Mount Lofty Ranges Region, South Australia 4
the Adelaide and Mount Lofty Ranges region is a biogeographically
unique part of South Australia
The combination of relatively high rainfall and hilly topography in the AMLR is not found elsewhere
in the state. The biodiversity of the region – the variety of plants and animals, communities and
ecosystems, and the ecological processes that sustain them – is similarly distinctive.
A broad range of vegetation types are represented in the region, including wet heathy (sclerophyll)
forests, drier heathy woodlands, grassy woodlands, grasslands, mallee, swamps, wetlands and
various coastal and estuarine ecosystems.
This diversity of vegetation types supports a wide range of flora and fauna. Over 450 native fauna
species have been recorded from the region, including over 75% of the bird species recorded within
South Australia (including a number of oceanic bird species that may only be occasional visitors to
the AMLR). The region also supports approximately 1,500 native vascular plant species.
the Mount Lofty Ranges is a terrestrial ‘island’ of habitat
The eucalypt forests and woodlands of the region represent an outlier of their distribution. These
forests form an ‘island’ separated from the cores of their distribution in eastern Australia by an
expanse of semi-arid mallee and dry woodland environments.
Reflecting this, many of the plants and animals that are found in the region represent populations
that are isolated from the cores of their distribution, or are present at the very edges of their
distribution.
The AMLR has high levels of endemism – species that are only found in the region. Many of these
endemic species are nationally threatened.
the Mount Lofty Ranges is part of a biodiversity hotspot
In recognition of the wide diversity of native species and the high levels of endemism – and the
fact that the remaining biodiversity is under a high level of threat – the Mount Lofty Ranges and
Kangaroo Island region was identified as one of 15 National Biodiversity Hotspots in Australia by the
Commonwealth Government in 2003.
The AMLR contains a number of significant and threatened ecological communities including
nationally significant wetlands, such as the critically endangered Swamps of the Fleurieu Peninsula
that provide habitat for significant fauna species, and Barker Inlet which provides habitat for
a number of migratory bird species of international significance. In addition, several AMLR
watercourses (the Currency, Tookayerta and Finnis Creeks) feed into the internationally significant
Coorong and Lower Lakes Ramsar wetlands.
The region also contains the nationally threatened ecological communities Peppermint Box Grassy
Woodland and Iron Grass Natural Temperate Grasslands.
5 Informing Biodiversity Conservation for the Adelaide and Mount Lofty Ranges Region, South Australia
the biodiversity of the AMLR is in a state of decline
Like all agricultural regions of Australia, the AMLR has changed dramatically since European
settlement. Vegetation clearance in the region has been extensive and only approximately 13%
of the original native vegetation of the region remains, based on current mapping. The AMLR
represents a highly fragmented landscape, with isolated remnants of native vegetation embedded
in a matrix of urban and agricultural land uses.
There are few intact areas remaining in the region. Most native vegetation has been modified
to some degree by human impact, and many areas are highly degraded. Many remnants are
managed for production outcomes such as grazing and agriculture on private land.
The widespread vegetation clearance in the AMLR has led to extensive declines in most native
species of the region. Many species have become extinct since European settlement, including nine
mammal species, three reptile species and 17 bird species. Almost 400 species are formally listed as
threatened under National or State legislation.
Many other species are considered to be declining or at risk of decline, most notably a large
number of bird species, with over 60 species listed on an initial list of declining birds.
The threats to the biodiversity of the AMLR are varied and widespread. They include the ongoing
impacts of historic clearance and fragmentation, combined with weed invasion, inappropriate
grazing regimes, introduced fauna species, altered hydrological cycles and fire regimes, urban
encroachment and recreational pressures. In the future, increasing populations and demands on
natural resources, along with the forecast predictions of climate change, have the potential to
further impact on and threaten biodiversity.
Conservation protection
Approximately 22% of the remnant vegetation is managed for conservation in dedicated reserves,
both publicly managed reserves and on private land. However, not all vegetation communities
are well represented in protected reserves. Analyses assessing the degree of protection for native
vegetation are presented in the following sections of this report.
Informing Biodiversity Conservation for the Adelaide and Mount Lofty Ranges Region, South Australia 6
PARt 2
Biodiversity State
and condition
This part contains information on the state and condition
of the biodiversity of Adelaide and the Mount Lofty Ranges.
Further information on the detailed condition and trend
of specific biodiversity assets can be found within Part 4.
The terrestrial and aquatic environments of Adelaide and the
Mount Lofty Ranges have been highly fragmented and modified.
The Mount Lofty Ranges are a well-defined stretch of ancient uplands and hills, extending from the
Barossa Valley in the north to Cape Jervis on the Fleurieu Peninsula. These higher areas are flanked
on their west and east by escarpments, undulating foothills, and then low-lying areas including
outwash plains and flats. Together these areas form the planning region defined as the AMLR for this
report (Figure 1.1 above). The topography varies across the region with the highest points exceeding
700 metres above sea level (MASL), steep fault-controlled escarpments ranging between 300-450
MASL, foothills between 150-300 MASL, and plains less than 150 MASL. This fine-scale topographic
and climatic heterogeneity is unique in South Australia, and important in explaining the biodiversity
value of the region.
The climate of the AMLR is Mediterranean-like, characterised by hot, dry summers and cool, wet
winters. However, there are significant climatic variations due to the topographic variability within
relatively small geographic areas.
Figure 2.1: Diversity of terrestrial land uses of the AMLR region
7 Informing Biodiversity Conservation for the Adelaide and Mount Lofty Ranges Region, South Australia