4 Bushland Management Zone
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4 Bushland Management Zone 4.1 Characteristics and Values This is the largest of the six management zones, covering around three-quarters of the Park. Manly Warringah War Memorial Park is the largest single area of bushland managed by a local council in Sydney’s northern beaches. Vegetation Communities and Flora The Park is predominantly a bushland reserve, dominated by Hawkesbury Sandstone vegetation, with six native vegetation communities plus areas of highly disturbed vegetation. The vegetation communities are shown on the following plan and their conservation status summarised in the accompanying Table (P & J Smith Ecological Consultants, 2003 and 2005). The Park is considered a floristically rich area, for an urban bushland reserve, with over 300 native plant species recorded (including 18 different native orchids). The Duffys Forest Endangered Ecological Community (left) occurs at several sites in the Park. The uncommon Sandstone Swamp vegetation community (centre) occurs at only one location in the Park’s north. Bloodwood- Scribbly Gum woodland (right) is the area’s major vegetation type, and also very common and well protected in the Warringah LGA. The most widespread vegetation communities in the Park are Sydney Sandstone Ridgetop Woodland (Bloodwood-Scribbly Gum Woodland) and Coastal Sandstone Heath, which occur on the sandstone ridgetops and slopes. Sydney Sandstone Ridgetop Woodland is the most common, and Coastal Sandstone Heath one of the more common, types of bushland found in Warringah. Both are very well represented in national parks and other reserves across Warringah (with more than 45% of their estimated 1750 extent protected). Sydney Sandstone Gully Forest (Peppermint-Angophora Forest) occurs widely in the Park, mainly along valleys and creeklines, and is a common vegetation type throughout Warringah. It is very well reserved in Warringah’s national parks and other reserves (with nearly 60% of its estimated 1750 extent protected). Duffy Forest (Silvertop Ash-Brown Stringybark Forest), a listed endangered ecological community, occurs in four limited areas mainly in the north of the Park. This community was not extensive in the Warringah area prior to European settlement, and only just over 20% of its estimated original 877 hectares remains (13% of which is now protected in national parks and Manly Warringah War Memorial Park PoM, Issues & Directions Discussion Paper – FINAL 15 Vegetation communities of MWWMP. (Source: Warringah Council GIS database) Manly Warringah War Memorial Park PoM, Issues & Directions Discussion Paper – FINAL 16 other reserves). This endangered ecological community is protected under the Threatened Species Conservation Act 1995 (TSC Act). A single small area of Coastal Sandstone Swamp is located in the Park’s north. Although not an endangered community, this vegetation type is rare in Warringah and is believed to have occupied only 80 hectares before European settlement. Of this 68 hectares survives, over 40% of which is protected in Warringah’s national parks and other reserves. This community is of local conservation significance due to its very limited distribution within Warringah. A vegetation community classified as “artificial wetland” occurs fringing the upper MWWMP reaches of the dam. This is a derived vegetation community, in that it occurs as a result of human modifications to the natural environment. However this community – of Remaining vegetation communities in Warringah, as at 2000. strands of reeds, sedges and other wetland (Source: Smith & Smith, 2005) plants fringed by low trees and shrubs - resembles vegetation found in the naturally occurring Coastal Freshwater Lagoon Swamp community which is a listed endangered ecological community. As a human created vegetation type this “artificial wetland” is not considered threatened, however its similarity to and endangered ecological community makes it of local conservation significance. A study of Warringah’s natural areas in 2003 allocated a conservation and management priority to each of the area’s natural vegetation communities, within the context of the Warringah local government area and Council’s responsibilities. As shown in the Table below, only the Duffys Manly Warringah War Memorial Park PoM, Issues & Directions Discussion Paper – FINAL 17 Forest and Freshwater Lagoon Swamp communities were assessed as the highest, Priority 1, conservation areas. Priority 1 areas are endangered ecological community listed under the under TSC Act 1995), or represent potentially important habitat for threatened (TSC Act listed) flora or fauna species, or communities absent or poorly represented in Garigal and Ku-ring-gai Chase National Parks. The Sandstone Swamp community was rated as a Priority 2 conservation area. These areas are considered important for the conservation of biodiversity at the local level, with a restricted distribution in Warringah or are absent or poorly represented in Garigal and Ku-ring-gai Chase National Parks. The other 3 vegetation communities – which make up the majority of this management zone and the Park overall – were rated as Priority 3 conservation areas. Priority 3 communities are considered well represented in Garigal and Ku-ring-gai Chase National Parks and common in Warringah. Two threatened plant species (TSC Act listed) have been recorded on the Park - Angus's Onion Orchid, Microtis angusii (a terrestrial orchid, usually associated with the Duffys Forest community, known from approximately 300 individual plants in the Warringah area) is considered endangered and Seaforth Mintbush, Prostanthera marifolia (a mint bush) considered critically endangered. Angophora crassifolia , a Eucalypt up to 15 metres high, has also been recorded on the Park and is of conservation significance and classed as a rare Australian plant. The condition of the Park’s bushland is generally good; however there are still around 100 weed species present within the area. Bush regenerators, both volunteer and professionals, rehabilitate the bushland on a regular basis to address areas degraded by weeds and other site disturbances. The initial community consultation has consistently identified the natural environment as one of the most highly valued aspects of the Park. Respondents valued the diversity of flora and fauna found within the Park (both common and rare or endangered species), the large and unfragmented character of the bushland (extending from valley to ridgetop), and the bushland’s “high quality” (as generally weed-free vegetation) and habitat value. The usage and aesthetic benefits of such a large and accessible expanse of the natural environment in an urban setting were also highly valued – notably the area’s “peace and quiet”, its scenic qualities, and as a place offering a physical, visual and recreational respite from urban living. Habitats and Fauna The Park’s bushland provides habitat for a variety of native fauna - including mammals, birds, reptiles, amphibians and fish. However the diversity and abundance of native mammals on the Park is lower than as recorded for surrounding national park - due to its size, “edge effects” and isolation. Mammals commonly recorded and within the Park include the Brushtailed Possum, Ringtail Possum, Brown Antechinus, Bush Rat, Long-nosed Bandicoot and Short-beaked Echidna – however the nocturnal habits of many mammal species means they are less frequently seen by visitors. Retiles are more readily observed, with common species including the Eastern Blue- tongued Lizard and Eastern Water Dragon. Lace Monitors, Southern Leaf-tailed Geckos, Diamond Pythons and Red-bellied Black Snakes also occur in the Park. Eastern Long-necked Turtles occur in the dam and other larger waterbodies. Common Eastern Froglets, Eastern Dwarf Tree Frogs and Eastern Banjo Frogs are also common. Australian Bass are found in Manly Warringah War Memorial Park PoM, Issues & Directions Discussion Paper – FINAL 18 both fresh and saltwater and are native to the Manly Dam area, while the dam was also stocked with Silver Perch in the past and it is believed to still occur in small numbers. Over 80 species of birds have been recorded in the Park, both waterbirds, and terrestrial species (as well as migrant and vagrant species). The Park’s avifauna includes many increasingly rare species in urban bushland areas, such as wrens and thornbills. Swamp Wallabies (le ft) have been sighted again in the Park in recent years, Water Dragons and the Brown Antechinus (centre) are relatively common, however the Long-nosed Bandicoot (right) is still absent from the Park most likely due to predation by introduced animals. Threatened fauna species recorded from within the Park include four terrestrial species - Rosenberg's Goanna, the Red-crowned Toadlet and single sightings of the Koala and the Spotted-tailed Quoll – and two mobile species – the Grey-headed Flying-fox and Eastern Bent- wing Bat. All four species are considered vulnerable (TSC Act listed). The Powerful Owl has also been recorded close to the Park’s boundary and sighted within the Park. The Climbing Galaxias (the most northerly population of this species in Australia) and the Heath Monitor, two uncommon species of interest, are also present. Swamp Wallabies have again been sighted in the Park in recent years. The Park’ links to adjacent natural areas, notably Garigal National Park to the west and to a lesser degree the McCombs Hill area and Condover Reserve in the south-east, are important in reinforcing its habitat values. Habitat degradation, especially