The ecological community described in this conservation advice is a type of eucalypt forest that is found in Tasmania. It is a wet sclerophyll forest with a canopy dominated by Eucalyptus viminalis and an understorey generally comprised of broad-leaved shrubs and ferns, occurring mainly on fertile, well-drained sites in the north of the state
Tasmanian white gum (Eucalyptus viminalis) wet forest
Status: Critically Endangered on the EPBC Act list
Government evidence of impact of climate change:
Conservation Advice for the Tasmanian white gum (Eucalyptus viminalis) wet forest
Threat factor Threat Status Evidence base Climate change Timing Ongoing Eucalyptus viminalis is known to be highly susceptible to and severe stress due to climatic factors and climate change projections weather Severity Severe indicate an increasing frequency and intensity of heat waves.
Changes in Timing Ongoing Any reduction in water availability; for example as a result of water dam building; stream diversion; increasing irrigated landuse availability Severity or climate change; creates significant stressors for canopy unknown trees; especially E. viminalis; compounding other threats and making them more susceptible to disease and dieback Scope unknown (Hattam; 2020).
The following are EPBC listed key threatening processes; current at the date of writing; that may be relevant to the ecological community or specific plants and animals that comprise it Land clearance Loss of climatic habitat caused by anthropogenic emissions of greenhouse gases Novel biota and their impact on biodiversity Loss and degradation of native plant and animal habitat by invasion of escaped garden plants; including aquatic plants Predation by feral cats and Infection of amphibians with chytrid fungus resulting in chytridiomycosis.
Patches with no sign of ginger tree syndrome or other significant canopy dieback; or in areas likely to be most resilient in the near future to the impacts of climate change.
Undertake activities to mitigate future climate change and therefore reduce the impacts of climate stress on this ecological community. 220.127.116.11 CONSERVE REMAINING PATCHES There should be no further clearance and damage to this ecological community because it has been greatly reduced in its extent.
This highly fragmented distribution makes it very susceptible to edge effects and to the actions of various threats; particularly invasive species; climate impacts; and cumulative losses of patches.
Climate change projections indicate an increasing frequency and intensity of heat waves in Tasmania (Grose et al 2010) and future climatic suitability modelling for E. viminalis (Harrison 2017) indicates that under a high emissions scenario consistent with current trajectories; around half of the ecological community s current range may be unsuitable for the dominant canopy species by 2050 and around 80 may be unsuitable by (Table 7).
Table 7 Area of current WVI that remains as suitable habitat for E. viminalis under future climate scenarios Suitable 2010 2039 Suitable 2040 2069 Suitable 2070 Area (ha) 4494 2629 of current range 83 49 18 Source Harrison 2017 and TASVEG unit WVI in DPIPWE (2013) The loss of live white gum trees; the dominant species in the canopy; is likely to substantially alter the character and function of the ecological community.
The projected loss in suitable climatic habitat over the next 50 years would also represent environmental degradation (change in an abiotic variable) sufficient to qualify for Critically Endangered status under Criterion C2a of the IUCN Red List of Ecosystems (Bland et al 2017). 6.1.4 Criterion 4 reduction in community integrity Eligible under Criterion 4 for listing as Endangered.
They also change over time; for example; in response to disturbance (by logging; fire; or grazing); or to the climate and weather (e.g. seasons; floods; drought and extreme heat or cold).
Integrating climate change into conservation and restoration strategies the case of the Tasmanian eucalypts. (Doctor of Philosophy PhD thesis); University of Tasmania; Hobart; Tasmania.
Small scale clearing and tidying of bushland around houses and other buildings; including for fuel reduction purposes; adds to this threat.
Severity Minor Scope Minority Threat factor Threat Status Evidence base Altered fire Timing Ongoing Wet forests such as the ecological community are adapted to regimes infrequent (fire intervals of 20 to 400 years (NFLC 2013)) Severity Severe high intensity fires; followed by mass seedbed germination.