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Background, caveats and Instructions for use of ACTmapi connectivity mapping Connectivity conservation seeks to enhance wildlife habitat and the ability of wildlife to move across the landscape between this habitat. It needs to consider both the habitat that an animal is able to live and breed in (habitat for settlement) and that which it can move through (habitat for dispersal).  As indicated in the following figure the spatial arrangement of habitat patches across the landscape will also influence whether a particular patch can be utilised as settlement and/or dispersal habitat.    The ability for wildlife to move across the landscape is becoming increasingly important to species and ecosystems in light of rapidly changing environmental conditions. Recent CSIRO work suggests that most animals of southern Australian woodlands and forests will not usually cross a canopy gap of more than 100m, and will not travel more than 1.1km away from at least a 10ha sized patch of suitable living habitat.  Thus consideration of wildlife connectivity needs to assess habitat condition and spatial arrangement, patch size and the canopy links between habitat patches.   Habitat value: The ACTMAPI mapping provides habitat value maps for species that typically utilise woodland or forest habitat or are able to utilise both (generalist habitat). Habitat value was derived from: the best available vegetation and land cover mapping for the ACT region;  fine scale (or paddock tree scale) canopy mapping undertaken using SPOT5 satellite imagery;  tree stand density predicted using a satellite radar-based measure of above ground biomass; and  an effective habitat area analysis that models and measures the habitat value and spatial relationship of a particular habitat patch to other patches of habitat. Large high valuehabitat patches close together scored highly, while isolated low value small patches scored lowly.  Regional Links: An analysis was then repeated 550,000 times that took random pairs of points from within any two patches of habitat in the ACT and nearby region and asked “What is the easiest route for a woodland, forest or generalist species to get from one habitat point to the other?” Paths through well connected habitat were repeatedly used to connect differing habitat patch pairs, and these well used paths are identified as regional links, which are the key pathways by which wildlife are likely to move across the ACT Region.    Use of Habitat value and regional link layers: Habitat value and the regional links layers are the most useful when assessing the potential impact of a development or conservation decision. Key considerations include whether an activity will result in;   loss of areas of high habitat value? If so will the proposal  significantly impact on a  habitat patch >100 ha; or  reduce a habitat area to less than 10ha; or  impact on a habitat patch of 5 -10 ha that could be important to establishing and maintaining a 10 ha habitat patch every 1.1km along a regional or local link.  result in gaps in key regional connectivity locations of >100m between habitat trees;  result in canopy gaps of >100m between local links connecting habitat patches identified as having high habitat value.  Ideally, any of the above type of losses should be avoided for landscape connectivity value across the ACT to be maintained. In most cases it should be possible to design development so that key thresholds are not broken or in the longer term it may be possible to match losses with restoration activities.  Local links and habitat patches: While regional links may be the least cost pathways they may not be able to be actually used by wildlife, if they contain canopy gaps of greater than 100m or if distance along a link between 10 ha habitat patches is greater than 1.1 km. The functionality of a regional link can be checked by overlaying the local links map (which shows all treed areas for which the stepping stone distance does not exceed 100m) and by also overlaying the distribution of habitat patches greater than 10ha.   Restoration guides - Canopy gap, habitat patches and priority restoration layers: The remaining layers are of particular assistance to the planning of restoration activities. Existing habitat patch sizes of 5 <10 ha are shown as potential areas to effectively create new 10ha patches. These are particularly important where the link distance exceeds 1.1km. Similarly the layer that shows areas where the current canopy gap is from 100m – 195m indicates those places where closing a current gap can be most easily achieved. The Patch Priority Restoration Area layer is derived from the effective habitat area analysis and indicates those areas where the spatial configuration of habitat across the landscape can be most improved through plantings or other regeneration/restoration activities    Caveats on data:   The ACTmapi connectivity mapping is multi-layered and there are many routes by which wildlife can move across the landscape. While allowing site specific consideration of connectivity value and restoration potential, the mapping should not be interpreted as a rigid framework of habitat and links that must all be conserved if wildlife movement is to be maintained across the ACT.  The mapping does provide a consistent and transparent means by which connectivity value can be considered within development and planning decisions and a guide to how connectivity across the ACT can be most effectively enhanced.  Habitat and linkage values rely on satellite and radar modelling of canopy. Thus, the mapping  is based on models  that are an approximate representation of the real world. There should be site-based assessment (validation) prior to making site specific development, planning or restoration decisions.  The CSIRO movement thresholds on which much of  the mapping is based are currently being tested in the field across the ACT. If this testing suggests that changes should be made to any of the parameters. the ACTmapi layers will be updated. There is the capacity within the raw data held by ESDD to produce mapping for an individual species of interest, provided that the threshold parameters for that species are known.  The focus of the modelling techniques used in this study is on connectivity in a fragmented landscape and as a result the mapping is suited for use across the ACT lowlands, but not within the continuous upland vegetation of Namadgi National Park and Tidbinbilla Nature Reserve.  The ACT connectivity mapping was undertaken by the NSW Office of Environment and Heritage. The study was funded as part of the offset package for the loss of woodland associated with the Kings Highway upgrade. A full study report has been produced, and is entitled Fine Scale Modelling of Fauna Habitat and Connectivity Values in the ACT Region. This study built upon an earlier report entitled the Ecological Connectivity for Climate Change in the ACT and surrounding region, commissioned by the ACT Government as part of Weathering the Change Action Plan 1. The report was undertaken by the Fenner School of Environment and Society, Australian National University. It is recommended that both reports be consulted when use is being made of the connectivity mapping available on ACTmapi.  Both reports can be downloaded from the EPD website at http://www.environment.act.gov.au/cpr/conservation-research/report_series.   Canopy Gap 100 – 195m: A tool which indicates where gaps in the local links canopy layer are from 100m – 195m wide. Theoretically this gap size could be closed by planting one tree in the middle of the gap, and thus this layer is a guide as to how canopy connection could be enhanced most effectively, through targeted clumped planting. Gridcode 1 = canopy gap 100m-195m Creative Common By Attribution 4.0 (Australian Capital Territory), Please read Data Terms and Conditions statement before  data use.

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