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Issues Water QualityConditionHarvesting and Marine FarmingGlobal Change |
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At a glance 
The issue Tasmania's marine ecosystems are some of the most diverse on earth and the temperate waters are host to both a large number of species and to many unique species that live nowhere else. They are an important part of the world's ecological riches. For example, in the Bruny Bioregion, almost every stretch of coast and bay contains different communities of plants and animals, which indicates very high diversity at the ecosystem level (Jordan et al. 1998). The sheltered, tidal waters of Tasmania's estuaries support unique communities of plants and animals, specially adapted for life at the margin of the sea. Estuarine environments are among the most productive on earth, producing more organic matter per year than equivalent areas of forest, grassland or agricultural land. Estuaries are essential for the survival of many species. Innumerable birds, mammals, fish and other animals depend on estuarine habitats as places to live, feed and reproduce. Migratory birds rely on estuaries as resting and feeding grounds during their long journeys. Estuaries are often referred to as the 'nurseries of the sea', as they provide many species of fish and shellfish with sheltered waters and wetlands for spawning, as well as suitable habitats for juveniles to grow. Hundreds of marine organisms, including commercially valuable fish species, depend on estuaries during some point in their life cycles. One of the objectives of the National Strategy for the Conservation of Australia's Biological Diversity is to 'establish and manage a comprehensive, adequate and representative system of protected areas covering Australia's biological diversity'. Marine reservation is an important strategy for effective biodiversity conservation of Tasmania's marine ecosystems. Marine protected areas offer important opportunities for study that can flow on to areas such as fisheries management. They also offer hope of passing on a more complete set of biodiversity into the future. Marine protected areas offer a range of protection to the marine environment-from multiple use reserves where resource exploitation is managed but allowed, to highly protected 'no take' reserves. In Tasmania, the approach to date has been to declare mostly small, but relatively highly protected MPAs. Macquarie Island is an International Union for the Conservation of Nature (IUCN) category 1a reserve, while Maria Island marine reserve is category II. The three smallest reserves are in category IV. The table explains the IUCN reserve management categories. Protected areas are necessary, but alone are not sufficient, for sustaining biological diversity. They must be complemented with ecologically sustainable management in the areas outside the reserves and sustainable management of wild fisheries and marine farming. This 'At a glance' section provides an overview of the issue of marine protected areas. Coastal reservation is not covered in detail here. More detailed information on marine protected areas and references are contained in the Marine and Estuarine Protected Areas Issue Report. Indicators are included that present data on marine protected areas, and the extent and condition of coastal, estuarine and marine habitats (see Indicators section). Coastal, estuarine and marine recommendations relevant to marine protected areas include: Conservation and Management of Coastal and Marine Biodiversity and Integrated Management of Catchments, Coasts and Estuaries. Favourable news- The Tasmanian Marine Protected Areas Strategy (DPIWE 2000 and DPIWE 2001) has been established to provide a comprehensive, adequate and representative marine protected area system, which includes at least 'some highly protected areas (IUCN Categories I and II) in each bioregion'. The strategy will be implemented after several stages of open consultation. In July 2003, the Resource Planning and Development Commission submitted the final recommendations report to the Minister for new marine protected areas to be established at Port Davey/ Bathurst Channel in south-west Tasmania and at the Kent Group of Islands in Bass Strait.
- In August 2000, a new marine protected area was declared around Macquarie Island, which is located in the Southern Ocean 1,500 km south-east of Tasmania. This reserve forms a part of the largest 'no take' marine reserve in the world when combined with the adjacent Commonwealth reserve. It has increased the area of high-level marine protection in Tasmanian waters from 1,416 ha, or 0.06% of Tasmanian coastal waters to 82,888 ha, or 3.52% of Tasmanian coastal waters. The five marine protected areas in Tasmania are Governor Island, Maria Island, Tinderbox, Ninepin Point, and Macquarie Island.
- Almost all of the existing reserves in Tasmania are highly protected 'no-take' areas, though recreational fishing is allowed in part of one reserve. There are three small reserves, and one medium size reserve. Excluding Macquarie Island, however, Tasmania has only 1,416 ha (0.06%), or less than one thousandth, of coastal waters protected.
- Benefits flowing from the existing marine protected areas include improved knowledge of marine ecology without fishing pressures. Ecological improvements are clearly apparent in the Maria Island marine reserve-the largest of the marine reserves around mainland Tasmania. The changes have become evident over a period of just 10 years (Edgar & Barrett 1999).
- Land tenure categories for 287 Tasmanian offshore islands were identified in the 'Tasmanian Marine Protected Areas Strategy Background Report' (DPIWE 2000). The largest number of islands within a single category is 88 (31% of 287), listed as non-allocated Crown Land. In contrast, 163 or 56% of islands had some form of conservation status such as Historic Site, Game Reserve, Coastal Reserve, Nature Reserve or National Park. However, the actual number of islands is greater than the 287 offshore islands identified in the 'Tasmanian Marine Protected Areas Strategy Background Report' (see 'Uncertain news'). Parks and Wildlife Management Plans for 88 offshore islands are drafted and going through the approval process.
- Many of the islands off the coast of Tasmania have largely been protected through a combination of their remoteness and inaccessibility. Being discrete ecosystems predominantly free from human interference, they may provide baseline information on evolutionary processes and harbour unique flora-for example, Maatsuyker Island's Westringia and Blandfordia species-and fauna, such as the Pedra Branca skink. Several islands such as De Witt Island and Actaeon Island, are nationally significant geoheritage sites.
- Improved understanding of reservation priorities has been provided through the preparation of comprehensive Statewide reports on the type, condition and conservation significance of Tasmania's estuaries (Edgar et al. 1999; Murphy et al. 2003). Edgar et al. (1999) identified 10 class A estuaries in Tasmania as being of critical conservation significance priority. Each of these 10 estuaries is the least disturbed estuary of a particular type, and, between them, they span nearly all of the biological and habitat diversity found within estuaries in the state. The 10 class A estuaries are North East Inlet, Black River estuary, Bryans Lagoon, New River Lagoon, Thirsty Lagoon, Tamar River estuary, Southport Lagoon, Bathurst Harbour, Payne Bay and Wanderer River estuary. The Tamar may seem a surprise inclusion in Class A list given the extent of human impacts on the estuary, but it is the sole inclusion in this class.
- The Tasmanian Aquaculture and Fisheries Institute (TAFI) Seamap Tasmania marine habitat mapping program is also enhancing the identification and selection of marine protected areas, as well as supporting other management decision-making. The Seamap Tasmania program produces maps showing the seabed in about nine categories of habitat type with supporting images and video. So far, the program has covered over 1,800 km, including the entire Bruny IMCRA Bioregion, the Tasmanian portion of the Twofold IMCRA Bioregion and part of the Freycinet IMCRA Bioregion (for example, Barrett et al. 2001; Jordan et al. 2002). Some limited mapping has also been conducted within the Davey IMCRA Bioregion. While the maps can only provide a snapshot for this time-and therefore cannot show historical trends-they are the basis for detecting changes in the future.
Unfavourable news- Apart from Macquarie Island, Tasmania has only four marine protected areas with a total area of 1,416 ha (0.06%) of coastal waters protected within marine protected areas. The existing reserves inadequately represent Tasmania's diverse marine ecology. Only three of Tasmania's nine IMCRA bioregions have reserves.
- Estuaries have the lowest levels of protection. There are no fully protected estuaries out of the 111 present in Tasmania.
- While there is progress on establishing a marine protected area planning system, the lack of a comprehensive marine planning system similar to that covering land means that resource management planning (e.g. for marine farming) and conservation planning do not take place in an integrated manner.
Uncertain news- Mapping of the extent of marine, coastal, and estuarine habitats-a key information source for determining priorities for marine protected areas-remains patchy as large areas remain to be mapped through 'SeaMap Tasmania'. Some data are available on the extent of broad aquatic habitat types, however, this is generally in depths less than 40 m. The extent of the intertidal habitats is based on Statewide Topographic Digital map layers (The LIST 2001). Very little is known about either the current condition of the ecology of coastal and marine habitats or of trends in condition and very little is known about the extent of habitats in marine waters deeper than 40 m, where the majority of sponge habitat occurs.
- The number of off-shore Tasmanian islands counted by various sources is quite variable, which can be explained as follows. Firstly, until very recently, no comprehensive map of all of Tasmania's islands existed. The LIST map layers now depict the physical islands above high water mark. According to this method, the main island of Tasmania is surrounded with about 370 islands greater than 1 ha and over 6,000 islets smaller than a hectare (The LIST 2001). Secondly, an island may be defined by name and there are 257 officially named islands in the DPIWE nomenclature database (13 March 2003) but that number does not include rocks, pyramids, stacks, towers and islets. In summary, the number of islands depends on the definition used. It is reasonable to state that over 300 islands and many thousands of islets surround the main island of Tasmania.
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