The Southern Highlands Shale Forest and Woodland of the Sydney Basin Bioregion ecological community is dominated by eucalypt trees and typically has a herbaceous understorey, but is variable in vegetation structure, ranging from a tall wet sclerophyll forest to more open, grassy woodland. It occurs in the New South Wales Southern Highlands region.
Southern Highlands Shale Forest and Woodland in the Sydney Basin Bioregion (EC62)
Status: Critically Endangered on the EPBC Act list
Government evidence of impact of climate change:
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Approved Conservation Advice (including listing advice) for Southern Highlands Shale Forest and Woodland of the Sydney Basin Bioregion (EC62)
Key threats currently affecting the ecological community are Vegetation clearing and landscape fragmentation (previously due to agriculture and forestry currently due to residential and commercial development) Inappropriate grazing; mowing and slashing regimes Removal of fallen timber and dead standing trees Invasion by weeds Invasion by introduced animals and aggressive native species Loss of fauna and associated ecological functions Inappropriate fire regimes Climate change. 2.1 Key Threatening Processes Key threatening processes listed under the NSW TSC Act and EPBC Act that are affecting the Southern Highlands Shale Forest and Woodland are Land clearance (EPBC Act) Clearing of native vegetation (TSC Act) Loss and degradation of native plant and animal habitat by invasion of escaped garden plants; including aquatic plants (TSC Act; EPBC Act) Invasion of native plant communities by exotic perennial grasses (TSC Act) Invasion of native plant communities by African olive (TSC Act) Invasion and establishment of exotic vines and scramblers (TSC Act) Invasion and establishment of Scotch broom (Cytisus scoparius) (TSC Act) High frequency fire resulting in the disruption of life cycle processes in plants and animals and a loss of vegetation structure and composition (TSC Act) Loss of hollow bearing trees (TSC Act) Removal of dead wood and dead trees (TSC Act) Competition and land degradation by rabbits (EPBC Act) Competition and grazing by the feral European Rabbit; Oryctolagus cuniculus (TSC Act) Herbivory and environmental degradation caused by feral deer (TSC Act) Competition from feral honeybees (TSC Act) Aggressive exclusion of birds from potential woodland and forest habitat by over abundant noisy miners (Manorina melanocephala) (EPBC Act) Aggressive exclusion of birds by noisy minors (Manorina melanocephala) (TSC Act)Predation by European red fox (EPBC Act) Predation by the European red fox (Vulpes vulpes) (TSC Act) Predation by feral cats (EPBC Act) Predation by the feral cat (Felis catus) (TSC Act) Predation; habitat degradation; competition and disease transmission by feral pigs (Sus scrofa) (EPBC Act) Loss of terrestrial climatic habitat caused by anthropogenic emissions of greenhouse gases (EPBC Act) Anthropogenic climate change (TSC Act) Further details about threats to the ecological community can be found at Appendix D. 3 SUMMARY OF ELIGIBILITY FOR LISTING AGAINST EPBC ACT CRITERIA Criterion 1 Decline in geographic distribution The Southern Highlands Shale Forest and Woodland is estimated to have undergone a decline ranging between 75 90 of its original pre European extent (Tozer et al.; 2010).
Climate change is likely to increase the severity of many current threats; as well as introducing new pressures on the community.
Climate change Climate change poses a serious long term threat to terrestrial and aquatic ecosystems with the potential to change the ecology of these environments through changes to species composition and function (Dunlop et al.; 2012).
In addition to threatening species that cannot adapt; climate change could also exacerbate existing threats such as habitat loss; altered fire regimes and the spread of invasive species.
Grazing pressure and associated detrimental effects such as depletion of the indigenous understorey; and ringbarking of some tree species may increase under forecast climate change.
Invasion by non native plant species is likely to increase in intensity; spread; and diversity; with some species taking advantage of climate change induced effects such as periodic depletion of ground cover due to drought and over grazing.
Altered fire regimes due to changed climate and weather; and due to changed vegetation structure and composition.
Whilst the ecological community will be negatively impacted by the effects of climate change; in a regional context it is still likely to play an important role in supporting ecological adaptation by providing refuge for species displaced from their preferred habitat.
Climate change is expected to cause increasing pressure on the ecological community through changes in temperature and rainfall patterns.
Reduction in integrity through climate change Climate change is likely to compromise the integrity of the ecological community both directly and by altering the survival rates of species.
These losses are compounded by climate change; and together with the ecological characteristics of the Southern Highlands Shale Forest and Woodland; as well as the nature of the ongoing threats; severely limit the likelihood of recovery of the ecological community.
In addition; extensive clearing; grazing; logging; weed invasion; altered fire regimes and changed hydrological patterns have also resulted in variation in form.
The ecological community is subject to a range of ongoing threats including clearing; fragmentation and other damage associated with rural residential development loss of ecological services associated with populations of fauna that have been lost or reduced weed invasion and inappropriate fire and grazing regimes.
Bursaria has often been removed from native vegetation patches for pasture improvement or by a change in fire regime; resulting in the likelihood that Christmas beetle populations will boom more often; with possible effects on the canopy trees (sensu Ridsdill Smith; 1970 Davidson Davidson; 1992).
It rapidly invades bushland; alters fire ecology in a manner that favours it and many non native woody weeds; chemically and physically suppresses other native plants; and changes the floristics; structure and faunal composition of remnants over time (Douglas; 2014).
Further; the frequent application of fire to reduce bushfire risk and or intensity in order to protect residential areas and infrastructure may impact on this ecological community; particularly on species that are more reliant on unburnt sites.
Conversely; the exclusion of fire for long periods can also have a detrimental impact on the ecological community; particularly through loss of understorey plant diversity.
Reduction in integrity though inappropriate fire and grazing regimes The ground layer of the ecological community is often extensively modified by grazing (NSW Scientific Committee; 2014; Tozer et al. 2010); leading to the loss of grazing sensitive; palatable species.
It is also likely to interact with other threats; such as changed fire regimes or invasion by weeds.
Nevertheless changes in temperature and precipitation; as well as influences on the fire regime and the competitive relationships between species; may further limit the recovery of the ecological community.
Summary Substantial clearing; severe fragmentation; weed invasion; inappropriate fire and grazing regimes; and associated changes to vegetation structure and loss of faunal components have substantially reduced the integrity of the ecological community across its distribution.
These include inappropriate grazing and fire regimes that alter the species composition (vegetation and faunal) and rural residential development leading to further clearing and degradation of remaining remnants.