Westernport Catchment Snapshot
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Westernport Catchment Snapshot 1. Overview of catchment 2. Highlights of the catchment – natural values 3. Good wins (programs/projects) 4. Key Issues Thursday 19 October 2017 Overview of Catchment Westernport catchment area 3,365 km2 2,232 km rivers & creeks Includes all Mornington Peninsula and islands Western Port (680 km2) Waterways include: - Cardinia, Toomuc and Deep creeks - Bunyip and Tarago rivers - Lang Lang and Bass rivers - Merricks, Main and Balcombe creeks Historical Changes Substantial changes to waterways and catchments in last 200 years e.g. - Draining Koo Wee Rup Swamp (formerly 400km2) 1857-1930s - Previously few streams flowing to north, now many artificial channels - Extensive catchment vegetation clearing - Dams and diversions e.g. Tarago and Cardinia Reservoirs, Bunyip Diversion - Progressive urban growth 1847 Future change……. e.g. Population growth Projected changes in climate /sea level ChangingRiver focus Health of waterway Monitoring management Secure water supply (e.g. Beaconsfield, Frankston 1910s-20s, Devil Bend and Tarago 1960s) Flood protection activities in 1920s-1950s in response to series of large floods in early-mid 1900s e.g. 1911, 24, 34 1960s+ minor wastewater treatment plants established to replace septics (increasingly water recycled) 1970s Environmental recognition e.g. Environment Protection Act (SEPP 1979, 2001), Western Port Bay study 1980s+ stabilisation works along channels e.g. Bunyip, Lang Lang, Cardinia 1982 Western Port nominated Ramsar site 1990s increased emphasis on ecological health of waterways 2000s marine national parks recognised (Yaringa, French Island, Churchill Island) Forest ~25% Agriculture ~70% Urban ~5% Catchment – Environmental Values Environmental Values: Environmental values • Birds • Fish • Frogs • Macroinvertebrates (water bugs) Environmental conditions • Platypus • Vegetation Aquatic macroinvertebrates Photos by John Gooderham and Edward Tsyrlin Environmental Values – Macroinvertebrates Based on surveys since 1990s and modelled predictions (‘LuMAR’ score) Stream health highest in forested headwaters, eastern rural catchments, and south eastern Mornington Peninsula Threats include: - Urban stormwater primary impact on invertebrate communities (water quality and flow) - Loss of instream and riparian habitat (vegetation, physical form) - Agricultural runoff - Changes in stream flows Environmental Values – Fish Photo by Rhys Coleman 18 native freshwater species (+8 exotic) Several estuarine species, including black bream, yellow-eye mullet, estuary perch, pale mangrove goby (FFG) Nationally significant species include, Photo by Tarmo Raadik dwarf galaxias, Australian grayling and Australian mudfish Freshwater crayfish e.g. Warragul burrowing cray (FFG) Threats to fish species include: • habitat loss/degradation (instream/floodplain) • several large barriers to movement • urban and agricultural stormwater • pest fish e.g. carp, Gambusia Photos by Tarmo Raadik Native Fish Photo by Neil Armstrong Photo by John McGuckin Environmental Values – Frogs Up to 14 species of frogs expected to occur in the catchment <40 frog records for many areas over past 5 years = no frog condition rating ‘High’ (Lower Bunyip and West Peninsula) ‘Moderate’ (Cardinia/ Toomuc/ Deep/ Ararat) Threatened Frogs The nationally listed Growling Grass Frog still occurs in some areas e.g. northern lowlands, Mornington Peninsula Southern Toadlet (Vulnerable in Victoria) Growling grass frog once more widespread but recent records on Nationally listed (Vulnerable) the Mornington Peninsula only Threats to frogs include: - habitat loss and fragmentation - introduced predators and disease Southern toadlet - aquatic pollution State advisory listed (Vulnerable) Photos by Peter Robertson Common Frog species Southern brown tree frog Striped marsh frog Common froglet Banjo/Pobblebonk frog Spotted marsh frog Photos by Peter Robertson Catchment - Environmental Values – Platypus • Regular surveys since 1995 • Key populations: - Bunyip River - Lang Lang River - Cardinia Creek (10 reintroduced 2004-2007) • Unconfirmed sightings e.g. Mornington Peninsula, Bass River (historical records) • Threats include: - urban stormwater (litter, loss of food) - loss of riparian vegetation - loss of instream habitat - Fragmentation/inbreeding Catchment - Environmental Values – Platypus Cardinia Creek Bunyip River Lower Tarago River Environmental Values – Birds Important bird habitats include: - Ramsar-listed Western Port - riparian areas in forested headwaters and peninsula - Tootgarook Swamp (Australasian Bittern) ‘Very High’ (SE Pen.) to ‘Low’ (Dalmore) for riparian birds. Much of catchment in good condition (but insufficient data) Developing a condition score for wetland birds Environmental Values – Riparian & wetland birds 249 bird species recorded in the catchment ‘Expected’ list of streamside birds is high at Red Knot 131 species e.g. White-bellied Sea-Eagle (John Barkla, Birdlife Australia) Little Grassbird White-browed Scrubwren Laughing Kookaburra Latham’s Snipe Nankeen Night Heron Blue-billed Duck Australasian bittern (John Barkla, Birdlife Australia) (John Barkla, Birdlife Australia) Threatened species include: Australasian Bittern Hooded Plover Eastern Great Egret White-bellied Sea-Eagle Helmeted Honeyeater (historically) Eastern Great Egret Lathams’ Snipe (Geoff Gates) (John Barkla, Birdlife Australia) Environmental Values – Ramsar 1 of 3 most important sites in Victoria for waterbirds e.g. - regularly supports over 10,000 waterfowl and over 10,000 shorebirds from 37 species - > 5 per cent of Victorian populations of 8 migratory shorebirds (East Asian – Australasian flyway) - Important drought refuge for inland populations International importance for 6 shorebird species (i.e. maximum counts > 1% of estimated global populations) - Eastern Curlew* (EPBC) - Australian Fairy Tern (EPBC) - Red-necked Stint* - Curlew Sandpiper* (EPBC) - Pied Oystercatcher - Pacific gull * = migratory Photos by Annette Hatton Environmental Values – Vegetation • Highest riparian vegetation values in forested areas of upper catchment • Extensive land clearing resulted in very low-moderate riparian vegetation condition in many areas • Draining Koo Wee Rup swamp lost much Tall Marsh, Seasonal Herbaceous Wetland and Swamp Scrub vegetation • Threats include: - Land clearing, stock access to waterways - Grazing by deer - Weeds e.g. Glyceria, willows, Spartina • Extensive riparian revegetation effort by many groups and organisations has led to substantial improvements Environmental Values – Vegetation Notable vegetation areas include: Upper Bunyip and Tarago rivers: extensive and intact Damp, Riparian and Lowland Forests with areas of Damp Heath. Tootgarook Swamp (Mornington Peninsula): 650Ha wetland supports a diverse mix of wetland vegetation communities and wetland dependent fauna including swamp skink (FFG listed). Western Port coast and estuaries: mangrove and saltmarsh communities with extensive seagrass meadows in the bay Labertouche Fauna and Fauna Reserve: Damp Heath and Wet Verge Sedge land supports important ecological values including the Warragul Burrowing Crayfish (FFG listed) Bass Valley riparian woodland (Bass River): largest remnant patch very rare Eucalyptus strzeleckii (FFG listed) woodland Mornington Peninsula waterways (esp Main Creek): remnant riparian woodlands, Damp Heath and Coast Banksia woodlands, freshwater and estuarine Tall Marsh vegetation Cardinia, Toomuc, Deep and Ararat creeks - South facing foothill waterways with high value riparian vegetation providing stability to high gradient streams and connection to Yarra catchment Dalmore outfalls: Seasonal Herbaceous Wetlands and Gippsland Plains Grasslands (both EPBC listed) Cultural Heritage • More than 2,000 Aboriginal sites are recorded in the Westernport catchment • Many near wetlands, river and creek corridors • Need to better understand how we incorporate cultural heritage into waterway management The Western Port District in 1840, from an original map by William Thomas, Assistant Protector of Aborigines (DPCD 2011). Catchment– Social Values Social Values • Amenity Expanded in new strategy • Recreation • Community Connection Social Values: Amenity, Connection and Recreation GOOD WINS - Projects/case studies Good Wins: Merricks Creek Estuary Management • MW co-ordinated a working group of community representatives, Mornington Peninsula Shire and DELWP • Baffles were installed to slow flows and re-establish a more natural opening and closing regime Good Wins: Rural Land Program – Seawright property Stock Containment Area Fence waterways Revegetate gullies Track system Land class fencing Fence Billabongs & River Frontage Good Wins: Community Co-operation, Cannibal Creek Tarago Environmental Bunyip and Tarago Environmental Flows Entitlement Held by Victorian Environmental Water Holder made up of:- o Minimum passing flows at various weirs and gauges o A 10.3% share of inflows and reservoir storage space o 3 GL of storage capacity Bunyip and Tarago Environmental Flows – 2016/17 outcomes Tarago - 1952 ML of water released. • 3 releases to maintain water quality, provide habitat for River Blackfish, platypus and macroinvertebrates and support spawning of Australian Grayling. • Undertook specific grayling spawning sampling. • Improved water quality outcomes. Tootgarook wetland Other Issues: Litter and pest plants and animals .