Priority actions – Moorabool River Catchment

Natural asset

Vulnerability rating*

Climate change threat (direct &/or indirect)

Guiding adaptation responses

Stakeholders

Moorabool River (reaches 32-8 and 32-9)

Very High

Higher temperatures and longer periods without rainfall will lead to less flow and reduced areas of refugia for aquatic species. More intense rainfall events may lead to more areas being susceptible to bank erosion.

Prioritise areas within reaches for targeted revegetation to improve shading and habitat as well as alleviate impacts of potential bank erosion. Protect riparian vegetation through fencing. Revegetate priority areas and provide instream habitat. Investigate options for removing artificial fish barriers e.g. weirs. Investigate feasibility of relocating isolated fish populations (Yarra Pygmy Perch).  Collaboratively review and optimise water management to increase waterway resilience. Continue to develop, implement and review Environment Water Management Plan for Moorabool River.

CCMA, NRM groups, Moorabool Shire, DELWP (ARI), EWH, Barwon Water, private landholders

Moorabool River (reaches 32-5 and 32-7)

High

Moorabool River (reaches 32-1, 32-2, 32-3 and 32-6)

Moderate

Moorabool River (reaches 32-4, 32-10, 32-11 and 32-12)

Low

Hovells Creek

Moderate

Higher temperatures and longer periods without rainfall will lead to less flow and reduced areas of refugia for aquatic species. More intense rainfall events may lead to more areas being susceptible to bank erosion.

Prioritise areas within reaches for targeted revegetation to improve shading and habitat as well as alleviate impacts of potential bank erosion. Protect riparian vegetation through fencing. Revegetate priority areas and provide instream habitat. Investigate options for and management of weir under Old Melbourne Road.

CCMA, NRM groups, COGG, private landholders

Hovells Creek Estuary and Limeburners Lagoon

Low

A sea level rise of between 0.8-1.1 metres by 2100, hotter temperatures, a reduction in rainfall and an increase in extreme natural events e.g. flooding are all expected to impact the ecology and dynamics of Limeburners Lagoon.

Assess natural freshwater flow regimes into Limeburners Lagoon and determine options for improved flows. Investigate opportunities to upgrade infrastructure that becomes inundated with high estuary water levels, with ‘green infrastructure’. Use LiDar to identify latitudinal and elevational gradients, areas of refugia and opportunities to enhance connectivity. Establish management agreements with private landholders within Limeburners Lagoon to improve resilience of estuarine vegetation to climate change Protect riparian vegetation through fencing Restore riparian zone using appropriate revegetation. Explore opportunities for a modified EstuaryWatch program for Limeburners Lagoon to help monitor changes associated with climate change.

COGG, CCMA, NRM groups, GA, private landholders

Native Vegetation – Lower Slopes/Hills Woodland and Riparian Woodland/ Forests

Very High

A hotter and drier climate may cause existing vegetation communities to change in their composition and structure, with some species being replaced by others. Fire regimes will be modified, most likely with more frequent and intense events. Vegetation communities may be vulnerable to environmental weeds. Some vegetation communities will be more vulnerable than others to the direct impacts of climate change e.g. Riparian Woodland.

Management should focus on maximising the resilience of communities and maintaining ecosystem function. In many cases this will mean managing native vegetation as we do today. Improving the current condition is likely to be important for the long-term viability of a community, with those in better condition more resilient to change in the short term, and more adaptable in the long term, due to their greater genetic, floristic and structural diversity.

NRM groups, CCMA, PV, LGAs, VicRoads, Trust, private landholders

Native Vegetation – Dry Forests

Moderate - High

Native Vegetation – Plains Woodland, Lowland Forest and Plains Grassland

Moderate

Native Vegetation – Heathy Woodland

Low

Wetlands – Coastal Wetlands (i.e. Point Lillias & Point Wilson)

Moderate

Coastal wetlands are very vulnerable to climate change. Increased drought frequency and intensity, decreases in freshwater inputs, rising sea levels and increases in coastal storm surges may impact these important ecosystems. These conditions may also change the character of coastal wetlands through a reduction in size, conversion to dryland or a shift from one wetland type to another e.g. brackish to saline. Under hotter and drier conditions as well as reduced inflows, acid sulphate soils in coastal wetlands may face an increased risk of being exposed. The retention of coastal wetlands will require planning approaches which allow for the migration of wetland communities, in order to avoid significant loss in both extent and character.

Assess the likely impacts of climate change on coastal wetland processes (i.e. tidal exchange, berm position and shoreline recession, entrance openings, water balance, geomorphology, water quality and biodiversity). Monitor sea level rise and associated impacts. Plan areas for marginal terrestrial vegetation e.g. Coastal Saltmarsh, migration due to sea level rise. Prioritise blue carbon habitats and investigate blue carbon opportunities. Investigate opportunities to upgrade infrastructure that becomes inundated with high sea water levels, with ‘green infrastructure’. Develop an ‘Adaptation Plan for Point Lillias and Point Wilson’ including adjacent habitats. Establish the baseline condition and extent of all EVCS within both Point Lillias and Point Wilson to monitor impacts of sea level rise.

PV, COGG, GA, NRM groups, private landholders

Wetlands – Lake Serendip and others

Very High - High

Wetlands that are highly vulnerable to a climate that is hotter and drier will reduce in both extent and quality. A reduction in rainfall and runoff could cause some temporary wetlands to dry up permanently. A reduction in water inflow may also cause an increase in the salinity of some wetlands, and changes in the types of vegetation communities that they can support. Wetlands that are reliant on groundwater/spring fed may also be impacted.

Management should focus on maximising the resilience of wetland communities and maintaining ecosystem function. In many cases this will mean managing wetlands as we do today. Improving the current condition is likely to be important for the long-term viability of a wetland, with those in better condition more resilient to change in the short term, and more adaptable in the long term, due to their greater genetic, floristic and structural diversity. Research potential recycled water/stormwater sources from Lara (both quality and quantity), for Lake Serendip. Develop a climate adaptation plan for Lake Serendip. Research ‘blue carbon’ opportunities of the catchment’s wetlands. Research potential groundwater sources (both quality and quantity) for selected wetlands.

PV, NRM groups

Agricultural Land

Low – Moderate

Climate change will have a direct impact on soil health and the ability of soil to support specific uses. Prolonged periods of higher temperatures and reduced moisture may lead to more areas being more susceptible to wind erosion. More intense rainfall events may also lead to areas of sheet, rill and gully erosion. Reduced vegetation cover due to climate change will also exacerbate these impacts. An increase in dryness and lack of moisture will also impact organic carbon in soil. Agricultural productivity may increase or decrease under a changing climate, depending on where it is located e.g. from grazing to cropping.

Addressing the impacts on soil will need to be assessed, planned and implemented at a site level due to a) the level of impact (often site-specific) and b) the adaptation response of the land manager of that site. A changing climate may mean that a current agricultural enterprise may need to also change to make better use of the climatic conditions, as well as changes to the soil properties that are expected. Research opportunities for soil carbon sequestration within this catchment should also be a priority.

Ag groups, NRM groups, CCMA, private landholders

Native Flora

Very High

The rate of climate change is likely to overtake the ability of most flora species to adapt and as a result, changes to the distribution of flora species are expected to occur. Changes in life cycle events e.g. flowering times, are also expected to greatly impact flora populations. There is also potential for greater tree mortality under climate change due to drought and temperature increases.

Management should focus on maximising the resilience of communities and maintaining ecosystem function. In many cases this will mean managing flora populations as we do today. Improving the current condition is likely to be important for the long-term viability of a community, with those in better condition more resilient to change in the short term, and more adaptable in the long term, due to their greater genetic, floristic and structural diversity. Protection and promoting the regeneration of large old paddock trees should be seen as a landscape priority due to their genetic capacity to survive through a significant range of climatic conditions and therefore provide a future seed source.

NRM groups, LGAs, CCMA, PV, DELWP (regional)

Native Fauna

Very High

Similar to flora species, the rate of climate change is also likely to overtake the ability of most fauna species to adapt and as a result, changes to the distribution of fauna are expected to be a major response to climate change. More mobile species may find refuge from increasing temperatures by shifting to higher, cooler elevations or cooler, south-facing slopes. Species already restricted to high altitudes without the option of upslope migration are expected to become extinct unless they are able to adapt. Some species will be more vulnerable than others to extinction. Species may not be able to shift to areas with suitable climatic conditions where they are located in fragmented habitats, or because of their limited dispersal ability. Species with small, isolated or fragmented ranges, or those with low genetic variation and specific climatic requirements, will be more vulnerable and local extinctions are likely.

Protect and enhance existing natural populations. Maintain and improve diversity. Accept and accommodate unavoidable loss and facilitate transformation, when possible. Reduce impacts from other impacts of climate change (i.e. invasive species & changes to flooding and fire regimes). Allow and create space for species shifts and movement throughout the landscape. Increase connectivity (i.e. buffers, corridors, stepping stones) and areas of refugia. Monitor species, communities and ecological processes.

NRM groups, LGAs, CCMA, PV, DELWP (regional)