Priority Bio-landscapes were identified across the region in the 2009 Biodiversity Sub-strategy. A 5 km by 5 km grid was placed across the region and those landscapes that had the highest concentrations of biodiversity value within the region were identified. Those landscapes that were identified as having a combination of high rarity for flora/fauna/communities and vegetation associations were classified as Highest Priority bio-landscapes. Those that were identified as having high rarity for flora/fauna/communities but the vegetation associations within them were not rare were classified as Second Priority Bio-landscapes. The full report can be read here: 2009 Biodiversity Sub-Strategy
The Bridgetown bio-landscape is found to the east of an area located between Manjimup and Bridgetown and is found in the Shire of Bridgetown-
Greenbushes and crosses over the boundary of the middle Blackwood and Warren catchments.
The Greater Kingston National Park and the Palgarup State Forest make up this bio-landscape and the Yerraminnup River and Dwalganup Brook flow through here with the Yerraminnup River and surrounding vegetation providing a regional ecological linkage through this landscape.
There is 1 DRF (Caladenia christineae) population identified and 32 threatened and priority fauna populations identified including species such as the numbat, woylie, quenda, western brush wallaby, wambenger or brush-tailed Phascogale, western ringtail possum and forest red-tailed black cockatoo.
Bridgetown bio-landscape and Climate Change
Projected level of risk due to:
- where Best Case = MIROC5 and Worst case = CanESM2 at 2090 and RCP8.5; read more here.
- Decreasing rainfall = annual rainfall change as % of initial
- Where Very High = greater than 25% reduction; High = 20-25% reduction; Moderate = 15-20% (Note: no where in the region is there projected to be less than 15% reduction in rainfall).
- Increasing temperature = change in maximum summer temperature
- Where Very High = greater than 4 degree increase (maximum projected being 4.7 degrees within the Region); High = 3-4 degree increase; Moderate = 2.5 – 3 degree increase; Low = 2 – 2.5 degree increase (Note: no where in the region is there projected to be less than a 2 degree increase which although lower than the very high 4 degree increase, will still have significant impacts on the environment).
This analysis is a simplistic way of looking at the potential risk of an asset to projected changes in rainfall and temperature. Assets may respond to climatic changes differently and species may be able to adapt in ways we don’t yet fully understand.
SWCC Strategic Priority
The Bridgetown bio-landscape is identified as a second order priority asset within SWCC’s NRM Strategy under the Terrestrial Biodiversity theme.
- 2009 Biodiversity Sub-Strategy for the South West Catchments Council Prepared for the South West Catchments Council by Ecosystem Solutions Pty Ltd 2009.
Header and thumbnail images supplied by Mike Christensen.