Lake Wollumboola (23843)
Australia, Australasia

Site overview

KBA status: confirmed

Global KBA criteria: D1a

Year of last assessment: 2009

National site name: Lake Wollumboola

Central coordinates: Latitude: -34.9517, Longitude: 150.7620

System: marine, terrestrial

Elevation (m): 0 to 10

Area of KBA (km²): 6.51472

Protected area coverage (%): 95.72

KBA classification: Global

Legacy site: Yes

Site details

Site description: The Lake Wollumboola IBA covers the whole of this coastal lake and its berm, on the mid-NSW coast near Nowra, south of Sydney. The boundary follows the National Park boundary except it follows the lake shore in the south-west where the National Park extends inland. It is one of the intermittently closed and open lakes or lagoons of the NSW coast. Its shallow depth (Kinhill 2000) and variable salinity permit a dense growth of the macrophyte Ruppia megacarpa and the algae Lamprophamnium (Pollard 1994) which support large numbers of waterfowl (Chafer 1996; Environment Australia 2001; Healthy Rivers Commission 2002). The lake is separated from the ocean by a narrow berm (~100 m across) which breeches only when the lake fills to more than 2.5 m mean sea level. Therefore the lake is only sporadically open to the ocean (e.g. in 1991, 1994, 1998), and then only for a very short time. The water level in the lake is therefore governed by inflows from the small catchment, wash-overs from the ocean during high seas and the competing influence of evaporation (Kinhill 2000). The diversity of bird species is inversely related to the water level of the lake (Keating & Pegler 2003). When this is shallow (e.g up to 1.2 m sea level) a wide variety of dabbling ducks, piscivores, large resident and small migratory waders, gulls and terns are supported. Above 1.2 m sea level large populations of Black Swan are still found provided that there is not a rapid rise in water level (e.g. because of high rainfall in the catchment) which denies that species access to its seagrass and macroalgae food supply. Little Tern continue to nest on the berm even at water levels up to 2 m sea level provided a gritty sand area is still present on the berm. The lake bed covers some 10 km2, and has a relatively small catchment of some 40 km2. The catchment of the lake is primarily vegetated with dry sclerophyll forest on all boundaries except the north-eastern corner where the small town of Culburra Beach is situated; 25% of the catchment is included in the NSW Jervis Bay NP and 10% of the catchment consists of the Culburra Beach urban area, where stormwater and sewage is controlled by Shoalhaven Shire Council.

Rationale for qualifying as KBA: This site qualifies as a Key Biodiversity Area of international significance that meets the thresholds for at least one criterion described in the Global Standard for the Identification of KBAs.

Additional biodiversity: Other birds found at Lake Wollumboola include the Little Tern (counts in 1996 = 63; 1997 = 47; 1998 = 36); Hardhead once exceeded the 1% threshold: 5137 in 2002 (Keating & Pegler 2003). Other species include Musk Duck (breeding), Australian Shelduck, Australian Wood Duck, Pacific Black Duck, Australasian Shoveler, Grey Teal, Pink-eared Duck, Hoary-headed Grebe, Great Crested Grebe, Darter, Little Pied Cormorant, Pied Cormorant, Little Black Cormorant, Great Cormorant, Australian Pelican (breeding), White-faced Heron (breeding), Little Egret, White-necked Heron, Great Egret, Intermediate Egret, Nankeen Night-Heron, Australian White Ibis, Royal Spoonbill, Osprey, Whistling Kite, White-bellied Sea-Eagle (breeding), Swamp Harrier, Brown Goshawk, Grey Goshawk, Wedge-tailed Eagle, Brown Falcon, Australian Hobby, Peregrine Falcon, Nankeen Kestrel, Buff-banded Rail (breeding), Spotless Crake, Eurasian Coot, Black-tailed Godwit, Bar-tailed Godwit, Whimbrel, Eastern Curlew, Marsh Sandpiper, Common Greenshank, Terek Sandpiper, Ruddy Turnstone, Great Knot, Red Knot, Sanderling, Red-necked Stint, Pectoral Sandpiper, Sharp-tailed Sandpiper, Curlew Sandpiper, Buff-breasted Sandpiper, Broad-billed Sandpiper, Pied Oystercatcher (breeding), Sooty Oystercatcher, Black-winged Stilt, Banded Stilt, Red-necked Avocet, Pacific Golden Plover, Grey Plover, Red-capped Plover (breeding), Double-banded Plover, Lesser Sand Plover, Greater Sand Plover, Black-fronted Dotterel , Red-kneed Dotterel, Masked Lapwing (breeding), Australian Pratincole, Kelp Gull, Silver Gull, Gull-billed Tern, Caspian Tern, Crested Tern, White-fronted Tern, Common Tern, Little Tern (breeding), Fairy Tern, Whiskered Tern, White-winged Black Tern, White-fronted Chat, Richard's Pipit. Non-bird biodiversity: Lake Wollumboola supports a population of the Green and Gold Bell Frog. Vegetation includes Wilsonia backhousei and Cuscuta tasmaniensis.

Other site values: NSW State or local government

Habitats

Land use: fisheries/aquaculture | nature conservation and research | tourism/recreation

IUCN Habitat	Coverage %	Habitat detail
Marine Coastal/Supratidal	90
Marine Intertidal	9

Threats

Summary of threats to biodiversity at KBA: Monitor fishing and the numbers of boats, together with their location on the lake. Monitor and regulate expansion of urban development. Monitor fox numbers.

Threat level 1	Threat level 2	Threat level 3	Timing
Invasive & other problematic species, genes & diseases	Invasive non-native/alien species/diseases	Named species	Ongoing
Biological resource use	Fishing & harvesting aquatic resources	Intentional use: subsistence/small scale (species being assessed is the target) [harvest]	Ongoing
Invasive & other problematic species, genes & diseases	Problematic native species/diseases	Named species	Ongoing
Pollution	Agricultural & forestry effluents	Nutrient loads	Only in the future
Residential & commercial development	Housing & urban areas		Only in the past and unlikely to return
Pollution	Garbage & solid waste		Ongoing
Human intrusions & disturbance	Recreational activities		Ongoing

Additional information

References: Chafer, C.J. (1996) An Ecological Assessment of the Proposed Culburra Urban Expansion Area and Environs. Report Prepared for Culburra Beach Progress Association and Lake Wollumboola Support Group. Chafer, C.J., Brandis, C.C.P. and Wright, D. (1999) Handbook of Birds Found in the Illawarra, Shoalhaven and Adjacent Tablelands. Illawarra Bird Observers Club: Wollongong, New South Wales. DEWHA (2008) A Directory of Important Wetlands in Australia. Wollumboola Lake - NSW094. http://www.environment.gov.au/water/publications/environmental/wetlands/database/ accessed June 2008. Healthy Rivers Commission. (2002) Independent Inquiry into Coastal Lakes. Final Report: NSW Government. Keating, J. and Pegler, J.M. (2003) Patterns of Waterbird Assemblages in Lake Wollumboola. New South Wales National Parks and Wildlife Service: Nowra, New South Wales. Kinhill Pty Ltd (2000) Lake Wollumboola Estuary Management Plan. Final Report. Morris, A.K. (2002) New South Wales Annual Bird Report 1999. Australian Birds 32/4. New South Wales National Parks and Wildlife Service (2003) Little Tern (Sterna albifrons) Recovery Plan. New South Wales National Parks and Wildlife Service: Hurstville, New South Wales. Pollard, D.A. (1994) Opening regimes and salinity characteristics of intermittently opening and permanently open coastal lagoons on the south coast of New South Wales. Wetlands (Australia) 13: 16-35.