Native flora and fauna are inherently diverse and exist within complex systems. Beyond the broad themes and management approaches that have been discussed in Part I, there is need for a framework which can both simplify this complexity and connect us more directly to the biodiversity assets and challenges in our own neighbourhoods and working environments. Biogeographic regions (bioregions) capture the patterns of ecological characteristics in the landscape or seascape, providing a natural framework for recognising and responding to biodiversity values. As bioregions reflect underlying environmental features, they can also be related to the patterns of use of land and sea. Thus they can be used to identify the relationships between many natural resource based activities and biodiversity assets.

Bioregions identified in Victoria form part of national frameworks for terrestrial and marine environments, the Interim Bioregionalisation for Australia (IBRA) and the Interim Marine and Coastal Regionalisation for Australia (IMCRA). These national frameworks were prepared through the cooperative efforts of Commonwealth and State/Territory agencies at the request of the Australian and New Zealand Environment Conservation Council (ANZECC). Of the 80 IBRA regions delineated across Australia, eleven occur in Victoria with eight of these shared with adjacent States. Of the 60 IMCRA regions delineated around Australia, five occur in Victorian waters with three of these shared with adjacent States. The broad scale that is appropriate for national purposes may not discriminate adequately between areas with meaningful differences at the state-wide scale.

This is particularly the case for terrestrial systems where further refinement has delineated 21 Victorian bioregions and described them in a Victorian context (see map showing location and relationships of national and Victorian bioregions). The following discussions of bioregions have been aggregated into descriptive areas, where appropriate, in order to retain the link to the national framework and to reduce repetitiveness in the text. The following table indicates the relationships between the national and Victorian frameworks and their presentation in the text.

INTERIM BIOGEORAPHIC REGIONALISATION ZONES FOR AUSTRALIA (IBRA)		VICTORIAN BIOREGIONS
MDD	Murray-Darling Depression	LM	Lowan Mallee
VVP	Victorian Volcanic Plain	MM	Murray Mallee
NCP	Naracoorte Coastal Plain	WI	Wimmera
VM	Victorian Midlands	VP	Victorian Volcanic Plain
NSS	NSW Western Slopes	GP	Glenelg Plain
RIV	Riverina	DT	Dundas Tablelands
AA	Australian Alps	GG	Greater Grampians
SB	Sydney Basin	GO	Goldfields
SEH	South Eastern Highlands	CVU	Central Vicorian Uplands
SCP	South East Coastal Plain	NIS	Northern Inland Slopes
FUR	Furneaux	VR	Victorian Riverina
SEC	South East Corner	VA	Victorian Alps
WSW	West and South West	HS	Highlands - Southern Fall
WAR	Warren	HN	Highlands - Northern Fall
WOO	Woolnorth	OR	Otway Ranges
BEN	Ben Lomond	WP	Warrnambool Plain
Note:	in some cases, particularly the Australian Alps, the delineation of Victorian bioregions differs in detail from the boundaries of the related IBRA regions. However, to maintain clarity in this schematic map, the original IBRA boundaries have been used in these cases.	OP	Otway Plain
		GP	Gippsland Plain
		WPR	Wilsons Promontory
		EGU	East Gippsland Uplands
		EGL	East Gippsland Lowlands

IBRA or IMCRA Region*	Descriptive Area	Victorian Bioregion
Murray-Darling Depression	VICTORIAN MALLEE	Lowan Mallee Murray Mallee Wimmera
Victorian Volcanic Plain	VICTORIAN VOLCANIC PLAIN	Victorian Volcanic Plain
Naracoorte Coastal Plain	GLENELG PLAIN	Glenelg Plain
Victorian Midlands	VICTORIAN MIDLANDS	Dundas Tablelands Greater Grampians Goldfields Central Victorian Uplands
NSW South Western Slopes	NORTHERN INLAND SLOPES	Northern Inland Slopes
Riverina	VICTORIAN RIVERINA	Victorian Riverina
Australian Alps	VICTORIAN ALPS	Victorian Alps
South Eastern Highlands	VICTORIAN HIGHLANDS	Highlands - Southern Fall Highlands - Northern Fall Otway Ranges
South East Coastal Plain	COASTAL PLAINS	Warrnambool Plain Otway Plain Gippsland Plain
Furneaux	WILSONS PROMONTORY	Wilsons Promontory
South East Corner	EAST GIPPSLAND	East Gippsland Uplands East Gippsland Lowlands
all terrestrial	WETLANDS	all terrestrial
all terrestrial	RIVERS AND STREAMS	all terrestrial
Victorian Embayments	BAYS, INLETS AND ESTUARIES
Otway
Central Victoria
Central Bass Strait	OPEN COASTS
Flinders
Twofold Shelf

In the aquatic environments within the landscape, ecological processes are largely dominated by the dynamic flows and fluctuations of water, with the adjacent terrestrial environment playing an important but secondary role. Accordingly, the terrestrial bioregions are less relevant for aquatic environments and the discussion of biodiversity in these environments is presented from a state-wide perspective for Wetlands and Rivers and Streams. In the marine environment, information is most readily available at a coarser scale than on the land and therefore the discussion of biodiversity is presented by aggregating IMCRA regions into Bays, Inlets and Estuaries and Open Coasts. All freshwater and marine environments can be profoundly influenced by activities in the surrounding or adjacent terrestrial environments, and the importance of managing vegetation, particularly in riparian corridors, for the appropriate quality and quantity of water is reflected in the discussion of the terrestrial bioregions. Knowledge of biodiversity assets across Victoria is variable but dynamic and continually improving. Our awareness of what and where species exist, of the habitats and communities they exist in, and of the related ecological processes, depends on the type of organism and the research effort in a particular area.

To enable comparison between bioregions, the following discussions use datasets that may not be the most sophisticated possible, but are available at a relatively consistent level across Victoria. For example, the general assessments of habitat/vegetation retention use Broad Vegetation Types (BVTs) rather than Ecological Vegetation Classes (EVCs). Current and pre-European coverage of BVTs are modeled from 1:250 000 scale land system, climate and other information and are thus limited in use to strategic overviews. EVCs are mapped at 1:100 000 and 1:25 000 scales based on substantial on-ground survey and are the vegetation mapping dataset of choice for detailed conservation planning and management; however there is not yet a complete state-wide coverage. Estimates of BVT retention are based on the Department of Natural Resources and Environment dataset for tree cover as at 1987, since a reassessment of tree cover as at 1995 is not yet completed.

Figures on the tenure status of BVTs are based on a broad division into conservation reserves, other public land and private land. More accurate information, particularly on conservation status, is available elsewhere for some parts of Victoria (e.g. East Gippsland Forest Management Plan, Central Highlands Regional Forest Agreement documents), where EVCs are the basis for determining representativeness of ecosystems in the reserve system and where the contribution of management zones in State forest is appropriately included.

Some biodiversity conservation and management issues are widespread in the environment (e.g. environmental weeds, introduced predators, population control of native grazers, fire regimes) or have particular challenges relating to extreme depletion (e.g. grasslands) or ecological sensitivities (e.g. old growth forest, dependent owls, rainforests). Although these issues are discussed in each bioregion according to their relevance, it is also effective to implement specific policy and planning approaches through Codes of Practice, targeted conservation programs and action plans.

This variety of management issues is reflected in the extent to which Victoria’s flora and fauna have become extinct or depleted. Around 600 of the 4000 native species of vascular plants and vertebrate animals have been identified as being threatened with extinction in Victoria.

Our knowledge of the conservation status of most invertebrates and non-vascular plants is much poorer. Clarification of the status of biodiversity in Victoria is provided by the Flora and Fauna Guarantee Act 1988, and so far:

• 22 potentially threatening processes have been listed, of which three have Action Statements;
• 23 ecological communities have been listed and three of these have Action Statements;
• 245 vertebrate animals and vascular plants and 25 invertebrates have been listed;
• 85 of these listed species are covered by Action Statements.

The challenge of securing these species and ecological communities and preventing further threats is clearly a complex one, and relies on a combination of state-wide and bioregional responses.

The discussion of each descriptive area is structured in the following way:

• A schematic map showing the location of the descriptive area within Victoria (with the bioregions shaded differently where there is more than one) against a background of Catchment Management Areas labeled as follows:

  MA - Mallee	WI - Wimmera
  GL - Glenelg	NC - North Central
  CO - Corangamite	PP - Port Phillip
  GB - Goulburn-Broken	NE - North East
  EG - East Gippsland	WG - West Gippsland;

• The Bioregional Landscape – placing the reader in their bioregional landscape through links to major features and administrative frameworks;
• The Natural Capital of the Landscape – summarising the natural history inheritance within the bioregion or area;
• Land Management Themes – how the landscape has been used in the past and how we are using it now;
• Biodiversity Condition – summarising the overall consequences for biodiversity of the variety of land uses;
• Management Responses – focusing on the most important challenges for biodiversity conservation and management.

Tables and charts for each terrestrial bioregion illustrating comparative data for the following:

• Pre-European area and percentage remaining of Broad Vegetation Types;
• Number of native terrestrial vertebrate and vascular plant species in each common life form;
• Land tenure of Broad Vegetation Types;
• Number of vascular flora and vertebrate fauna species in each rare or threatened category for each common life form;
• Proportion of vertebrate fauna and vascular flora that are threatened, not threatened or introduced.
• Similar information is provided for each aquatic descriptive area.