Ecosystem types within Lake Macquarie City
Nine broad ecosystem types, identified within Lake Macquarie City, are included in Council's Community Ecosystem Monitoring Program. Area and per cent cover for each ecosystem type are shown below. All areas are approximate and taken from vegetation mapping undertaken by the Hunter and Central Coast Regional Environmental Management Strategy (HCCREMS). A flagship species has been selected for each ecosystem type.
Proportion in hectares of each ecosystem type.
|Ecosystem type||Ha (%)|
|Heath complex||1200ha (2%)|
Only 1 per cent of the city is rainforest, being remnants of more extensive forests, which grew over much of the Australian continent hundreds of millions of years ago, but now mostly found in small fragments in valleys, sheltered from bush fires and drying winds.
While rainforests are generally found on moist and more fertile soils, such as along creeks, this is not always the case. For example, two types of rainforest found within the City include littoral rainforest occurring close to the coast (such as near Swansea Heads and Green Point) and temperate rainforest (found in the Watagan Mountains). Both rainforests have different plants and animals, but in both cases it is most often fire, rather than poor soil or lack of rainfall, that stops them expanding over time.
The Superb Lyrebird (Menura novaehollandiae) is the flagship species for rainforest in. Its distribution appears to be limited by the availability of subtropical and temperate rainforests.
Our waterways are typically, but not solely, freshwater and include approximately 1 per cent of the City. The thousands of kilometres of waterways in the City may be perennial or intermittent, flowing in natural or artificial (lined) channels and include tributaries, creeks, and streams with associated riparian animal and plant communities within five metres of the edge of the waterway.
To represent the beauty and fragility of our waterway ecosystems, the Australian Emerald Dragonfly (Hermicordulia australiae) has been selected as this ecosystem's flagship species.
Lake Macquarie is a natural estuarine lagoon with an area of approximately 110km2 covering approximately 15 per cent of the City. The lake ecosystem includes all of Lake Macquarie, Swansea Channel and the tidal mouths of the main creeks entering the lake.
The lake is quite diverse in itself. Depending on where you are in the lake at any one time, you will find different degrees of tidal influence, water movement, water temperature, water depth, saltiness, water clarity, fringing vegetation and underwater habitats such as seagrass meadows, rocky reefs or sandy flats.
The number of aquatic marine animals supported by the lake is many and varied and vegetation types associated with the lake ecosystem include mangroves, saltmarsh and seagrass, which are particularly important for providing habitat. Seagrasses grow on the bottom of the lake if the water is clear enough, providing habitat for the young of many recreational fish caught in the lake and ocean. Seagrass (including Zostera capricorni, Halophila ovalis, Posidonia australis and Ruppia megacarpa) is indicative of good water quality and has been selected as the City's flagship species for the lake. Monitoring over the past 10 years has shown that light penetration has improved by over a metre, allowing a measurable expansion of seagrass re-colonising deeper areas.
The coast ecosystem, an area of transition between the land and ocean, covers about 5 per cent of the City and is characterised by beaches, dunes, rocky headlands and estuaries. It is defined as an area from the highest high tide to 15m depth offshore, a highly turbulent zone, continually changing with tides, storms, and winds.
Lake Macquarie City has approximately 34km of coastline stretching from Leggy's Point in the north to Moonee Beach, just south of Catherine Hill Bay.
Areas along the coast, such as the rock platform at Swansea Head, are regarded as having the highest diversity of species in the coast between Sydney and Newcastle. However, our local area contains no coast or ocean reserves.
Our rocky shores and platforms are home to gastropods, sea stars, urchins, octopus, predatory snails, and sessile species such as barnacles, oysters, and the City's flagship species selected to represent the coast, Cunjevoi (or sea squirts) (Pyura stolonifera).
Forest ecosystems make up approximately 24 per cent of the City. The bulk of our forests are located on the slopes of the Watagan Mountains where higher rainfall and fertile soils support both wet and dry sclerophyll forests. "Sclerophyll" refers to hard ("sclero") leaves ("phyll").
Forests have a canopy of tall, smooth and rough-barked gum trees, mostly within the Eucalyptus or Corymbia genus. Angophoras also occur, but are less common than in Woodlands. In wetter sites, wet sclerophyll forests may gradually transition to rainforest if fire is absent for a long time.
Forest ecosystems are being progressively cleared for new urban development. This reduces habitat for species threatened with extinction in New South Wales, such as the Powerful Owl (Ninox strenua), the City's flagship species for forest ecosystems.
Approximately 29 per cent of the City's remaining bushland is comprised of woodland ecosystems, particularly in the area between the M1 freeway and the lake, where much of our urban development is located. Woodland intermixes with areas of forest and heath complex, depending on soil fertility, moisture levels and drainage.
Clearing for new urban development is affecting our woodlands more commonly than any other ecosystem. This habitat is relied on by the City's woodland ecosystem flagship species, the Grey Kangaroo (Marcropus giganteus) and more than 20 other species already listed as threatened with extinction in New South Wales.
Heath Complex ecosystems are typically coastal, making up 2 per cent of the City and occur on sandy soils, or poorly drained exposed sites, most commonly in small patches along and near coastal wetlands. The 'complex' part of the name refers to the fact this ecosystem is comprised of a variety of vegetation types, from headland heaths (dominated by Banksia and Hakea) to Spinifex contained within maritime grasslands behind our beaches.
The Northern Brown Bandicoot (Isodon macrourus) is the flagship species for heath ecosystems in Lake Macquarie City.
Wetlands cover around 5 per cent of the City with State Environmental Planning Policy No. 14 - Coastal Wetlands (SEPP 14) providing protection for 47 wetlands across the local government area.
A wetland is land periodically or permanently inundated with water, with aquatic plants such as rushes, reeds and sedges growing above the water. The two main types are freshwater and saltwater wetlands. Wetlands act as a filter preventing pollution from entering creeks and lakes and are protected from development by law. Local wetlands such as the Riparian Melaleuca Swamp Woodland, Swamp Mahogany - Paperbark Forest and Swamp Oak Rushland Forest have also been recognised as endangered ecological communities due to continuing threats and disturbance.
Wetlands are high in nutrients and often include important food sources for native animals. For example, Swamp Mahogany leaves are favoured by Koalas, and the blooms provide nectar in winter when few other trees are flowering.
Of some 216 Australian frog species, about 20 occur locally, many of them in our wetlands. However, common frog species live in all types of habitat where there are ponds with trees around, even in our suburbs. The Peron's Tree Frog (Litoria Peroni) live in these areas for part of their life and has been selected as the flagship species for wetlands in Lake Macquarie City.
Adjoining the outer edge of the coast ecosystem, the ocean ecosystem includes the area greater than 15m deep, extending out to the State boundary at three nautical miles (about 5km), which coincidently is about the oceanic horizon if you look from the shoreline. It comprises about 18 per cent of the area of the City. This body of oceanic water is part of the Tasman Sea, itself part of the Pacific Ocean.
The ocean off Lake Macquarie City is part of the Eastern Warm Temperate Zone and is influenced by the East Australian Current, which carries warm water from north to south at an average rate of two to three knots (3.5 to 5km/hour). The zone is not uniform and comprises a series of embedded, continually changing eddies and back currents.
Many sediments, nutrients, and organisms travel freely within this seamless ecosystem which plays an essential part in the oxygen, nitrogen, carbon and water cycles, essential for life. In fact, it is home to marine algae that supply us with two-thirds of the oxygen we breathe. Scientists are watching with interest to see what changes may occur with warming temperatures and changes in salinity and acidity.
The flagship species selected to represent the ocean ecosystem is the Eastern Blue Groper (Achoerodus viridis).
Page last updated: 08 November 2017