Three broad topic areas are included in the Coastal, Estuarine and Marine Chapter: water quality, condition (ecological), harvesting and marine farming; and global change. Issues addressed within these broad topic headings are as follows: Water Quality in Tasmanian Estuaries; Algal Blooms; Discharges to Estuaries; Ecological Condition of Coastal, Estuarine and Marine Habitats; Threatened Species and Communities; Marine Pests and Diseases; Marine and Estuarine Protected Areas; Coastal Land Use Change; Wild Fisheries; Marine Farming; Adapting Coastal Settlements to Climate Change. Further information on these issues is provided in the More detailed information on these issues is provided in the Coastal, Estuarine and Marine Chapter.

Water Quality in Tasmanian Estuaries: Since 1996 there have been significant reductions in pollutant loads to the Derwent, particularly faecal bacteria (greater than 90%) and heavy metal loads (greater than 50%),and a decrease in total suspended solids loads (TSS) (17%). Many estuaries have a number of water quality issues stemming principally from catchment land uses and discharges from point sources. Key issues include heavy metal contamination, elevated nutrient concentrations, depressed dissolved oxygen levels, organically enriched sediments, and intermittent faecal contamination of recreational areas. Some major estuaries-such as the Huon-have, in general, very good water quality.

Discharges to Estuaries: Records show a decrease in many of the contaminant indicators in the Derwent estuary. There has been a sharp decrease in faecal bacterial loads (>90%) and heavy metal loads (>50%), and a decrease in TSS (17%). Trends since 1996 indicate a slight increase in nutrient loads being discharged into the Derwent estuary. The increase has been caused by increased discharges from Sewerage Treatement Plants and Waste Water Treatment Plants. An increase has occurred in discharged dissolved inorganic nitrogen (DIN) (8%), total phosphorus (TP) (17%) and biochemical oxygen demand (BOD) (15%). On the west coast, several mining facilities, such as Goldamere at Savage River, and the Renison Bell mine, are associated with discharge of contaminants to local waters. The principal concern is the Mount Lyell copper mine, which has a history of acid mine drainage and waste water discharge from mining operations that killed virtually all aquatic life in the King and Queen rivers. This situation continues today.

Algal Blooms: The Estuarine Health report for 22 estuaries (Murphy et al. 2003) reported that some estuaries in the north-east of Tasmania are susceptible to eutrophication (including algal blooms) based on high recorded levels of chlorophyll. Ansons Bay regularly recorded high to very high chlorophyll levels and the upstream sections of Little Musselroe estuary and Boobyalla Inlet were medium-high upon occasion. In other parts of the State, the Meredith, Browns and Don River estuaries also showed high to very high chlorophyll levels on some occasions.

Ecological Condition of Coastal, Estuarine and Marine Habitats: Measured improvements in marine habitat condition have been documented in the Maria Island Reserve-the largest of the marine reserves around Tasmania other than the Macquarie Island Reserve (Edgar & Barrett 1999). Statewide work measuring marine and coastal biodiversity through surveys of fishes, invertebrates and plants of reef habitats has been undertaken by Edgar et. al. (1997). In 2000 a detailed and comprehensive sea floor habitat-mapping program-Seamap Tasmania- commenced. The first series of maps from this program reveal the extent of some habitats for the first time.

Threatened Species and Communities: Currently, the Tasmanian Threatened Species Protection Act 1995 lists three coastal, estuarine and marine animal species as extinct, 26 as endangered, 18 as vulnerable and 11 as rare. Eight species have shifted closer to extinction since the last SoE Report. There are 10 new coastal, estuarine and marine animal species listed as threatened under the Tasmanian Threatened Species Protection Act 1995 since the last SoE Report in 1997. However, the state of knowledge about Tasmania's threatened species including their habits, distribution, numbers and ecological relationships is poor.

Marine Pests and Diseases: Tasmania has a significant marine pest problem with 58 species such as the Northern Pacific seastar, the Japanese kelp, and the toxic dinoflagellate invading our waters. As an indication of the extent of the problem in Tasmania, authorities in Port Phillip Bay (Victoria) and New Zealand have declared that ballast water from Tasmanian ports is too high a risk. These ports do not allow ships to discharge ballast water originating from Tasmania in their waters. No indicators were included in the Issue Report.

Marine and Estuarine Protected Areas: 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 included with the adjacent Australian Government 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 3.518% of Tasmanian Coastal Waters. Excluding Macquarie Island, however, Tasmania has only 1,416 ha (0.06%), or less than one thousandth, of coastal waters protected.

Wild Fisheries: While direct measures of the stock of wild fisheries are often difficult to obtain, regulations and licencing conditions indicate management intervention to provide for the sustainability of the resource. Present trends suggest that wild fisheries are in a healthy condition, however, this situation will only continue with continued protection of natural resources. Data on populations of non-commercial species is severely limited and the resource status for most scalefish fisheries is unknown. The status of 12 of the top 20 valued commercial fisheries in 1996-2000 was unknown.

Marine Farming: Marine farming is susceptible to a variety of environmental influences, including catchment condition, reduction of environmental flows, pollution of estuarine waters, and algal blooms. Marine farming has the potential to cause environmental harm if unregulated. There has been a 31% increase in the number of licenced marine farming leases in Marine Farm Development Plan areas between 1997 and 2001. Marine Farm Development Plan areas cover a total area of 466,111 ha, with 1.8% of this area being occupied by 185 marine farming leases (DPIWE unpublished data 2001). While there has been an overall increase in the number of leases, there has been a shift in the licensed species attached to the leases. An overall decline occurred in the number of species attached to licences, but there has also been an increase in the number of licences held for the two major species groups-Pacific Oysters and Atlantic Salmon.

Adapting Coastal Settlements to Climate Change: Scientists around the world are generally in agreement that over the last 100 years there have been a number of measurable changes to the planet's climate. The planet's coastal areas are projected to be influenced by a number of climate related changes, including: a higher sea-level, more frequent and more severe storm events, more frequent and more intense low-pressure systems, changes to short term climatic cycles such as El Nino/La Nina, and an increased number of high rainfall events likely to cause floods. Some of these impacts will be gradual while others will be sudden and extensive following major events such as storms. Changes can affect existing infrastructure and investment on the Tasmanian coast. Some 975 km (approximately 15%) of the coastline contains low-lying erodible shorelines potentially at risk of recession and flooding. A further 1,147 km (18%) contains low-lying shores mainly at risk of increased coastal flooding.