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Issues Water QualityConditionHarvesting and Marine FarmingGlobal Change |
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At a glance 
The issue Wild fisheries include commercial and recreational sea fisheries. This Issue Report describes the state of wild fisheries within the Tasmanian jurisdiction. For most species the jurisdiction of Tasmanian fisheries, extends to three nautical miles offshore, although for the rock lobster, abalone, and some minor fisheries jurisdiction extends to 200 nautical miles. Some commercial fisheries may occur within three nautical miles (shark, blue eye trevalla, the south-east fishery) but are under Australian Government jurisdiction and are therefore not included. Many Tasmanian coastal towns such as St Helens, Triabunna, Dover, Currie and Strahan continue to rely substantially on fishing, while for many other Tasmanians it is their main source of recreation. In 2000, the landed value of Tasmanian fisheries was in excess of $170 million (predominantly comprised of abalone and rock lobster). The harvesting of fish, crustaceans and molluscs from the marine environment is a major human activity affecting marine biodiversity. Total fish catch may give an estimate of the magnitude of pressure from harvesting biomass from the marine environment. Where management controls are effective, the mixture and rank of species in the top 20 commercial fish species will be relatively stable, or change very slowly. However, for some fisheries variability can be driven by environmental parameters. Of the 230 fish species commonly caught in Tasmanian waters, 35 have been identified as the target of commercial and recreational fishers. Of the 20 top commercial species, 5 are considered fully fished, 1 over fished, 1 under fished, 1 improving, and 12 are considered unknown due to insufficient data (DPIWE unpublished data). Commercial and recreational fishing activities can change the natural ecology of an area by reducing the numbers of target species, but it is often difficult to assess the impact of fishing activities. Fishing gear can also cause damage; scallop dredges and trawl gear, for example, disturb the seabed, causing incidental mortality to both target and non-target species. For example, the Issue Report on Ecological Condition of Coastal, Estuarine and Marine Habitats reports on evidence of losses of shell (molluscan) species over the past 150 years in the shallow, sheltered estuarine waters of the south-east (Samson & Edgar 2001). Further work by the same authors suggests that while there are many factors at work-including siltation and pollution-the pattern of losses seems to correspond to the rise, and then collapse, of the oyster and scallop dredging industries. Participation in recreational fishing has many positive social and economic benefits. Nevertheless, both the commercial and recreational fishing effort needs to be taken into account in sustaining fisheries. Recreational catches of several key species probably exceed the commercial catch. Since 1996, recreational licences for abalone have increased by 77%, rock lobster pot and dive licences by 40% and 43% respectively, and recreational gillnet by 24%. The increase in the number of recreational licences of rock lobster is an issue that needs to be considered, as recreational effort tends to be concentrated on shallow accessible areas. The level of participation in recreational fishing is confirmed by the results of the National Recreational and Indigenous Fishing Survey. The survey identified that Tasmania had a participation rate in recreational fishing of 29.3% of the population, which was well-above the national average participation of 19.5%. As a proportion of the population, Tasmania and the Northern Territory had the highest rates of fishing activity of 6.55 fishing days compared with a national average of 6.13 fishing days (Henry & Lyle 2003). Other issues that need to be considered for the marine environment are the accidental by-catch and subsequent waste of non-target species, illegal fishing, over-fishing by both commercial and recreational fishers, ghost netting (where abandoned nets drift with the currents, continuing to capture and kill fish), and rubbish from fishing activities. More selective fishing equipment, legislation, policing, education and better awareness are being implemented to combat these problems. This 'At a glance' section provides an overview of wild fisheries in Tasmania. More detailed information and references are provided in the Wild Fisheries Issue Report. An indicator on the total seafood catch and estimated wild fish stocks is provided. Case Studies are also presented on Rock lobster fishery and Inshore trawl fishing. A recommendation is provided on Wild Fisheries. Favourable news- While direct measures of the stock of wild fisheries are often difficult to obtain, regulations and licencing conditions, as outlined in the initiatives below, indicate management intervention to provide for the sustainability of the resource.
- In the last five years, significant management changes have included the introduction of management plans for all major fisheries, quota in the rock lobster fishery, and increased controls on gear usage in the scalefish fishery. Zonation in the abalone fishery has been introduced to manage the distribution of effort, and protect the accessible areas from high fishing pressure and over exploitation.
- The current management approach to the abalone fishery is aiming to move fishing effort from east coast to west coast stocks. Stock assessment of blacklip abalone suggests a decline in two regions of the eastern zone, but that the western zone appears healthy with catch rates continuing to rise. The greenlip fishery in the Furneaux group has stabilised and stocks may be rebuilding. While the recreational catch of abalone is relatively small it is likely to be significant in more accessible areas.
- Annual fishery stock assessment reports for major fisheries have been introduced and export fisheries are required to report against ecologically sustainable development principles. Tasmania has prepared reports for the Department of Environment and Heritage (Australian Government) for both the abalone and rock lobster fisheries. These reports have been approved.
- To improve the sustainability of fishing, licence conditions for recreational fishing have been amended since 1996 in relation to gear restrictions, size limits, and bag limits. The 'National Recreational and Indigenous Fishing Survey' was undertaken as a joint initiative of Australian and State governments to obtain fisheries statistics to support the management of non-commercial fishing in Australia. The aims of the survey were: to obtain reliable, consistent and comparable data Australia-wide on angler participation and demographics, catch and effort, attitudes and awareness, and economic activity; to obtain information on indigenous fishing in Australia to help achieve a wider understanding of a range of issues, including the important role it plays in many indigenous communities; and to obtain information on international tourist fishing activities (Henry & Lyle 2003).
- Total seafood catch and wild fisheries stock assessments for the period 1996-2000 suggest relative stability in Tasmanian fisheries. In particular:
- Stable catches were recorded for 13 of the top 20 commercial fisheries over the period 1996-2000. Fisheries recording stable catches are highlighted in the indicator entitled Total Seafood Catch and Estimated Wild Fish Stocks. These were blacklip abalone, rock lobster, greenlip abalone, giant crab, wrasse, Australian salmon, garfish, blue warehou, flathead, bastard trumpeter, flounder, whiting, and jack mackerel.
- Increasing catches were recorded for 4 of the top 20 commercial fisheries in the period 1996-2000. Commercial fisheries recording increasing catches are highlighted in the indicator entitled Total Seafood Catch and Estimated Wild Fish Stocks. These were striped trumpeter, calamari, octopus, and arrow squid.
- Catches of the two most valuable fisheries in Tasmania, blacklip abalone and rock lobster, consistently ranked within the top three in the total seafood catch between 1996 and 2000. This consistency is predominantly due to sustainable fishing practices in these fisheries and the comparatively low volume and value of other fisheries, particularly finfish species. The western zone blacklip fishery appears to be healthy with catch rates continuing to increase, indicating that stock levels are unaffected by the increased catch. The greenlip fishery in the Furneaux group has stabilised and stocks may be rebuilding, but increased catches in the north-east and north-west need monitoring.
- Catch rates for rock lobster in Tasmania remained relatively constant or increased during the 1970s and early 1980s prior to a decline to record lows in the mid-1990s. This has been followed by minor recovery, due largely to new management arrangements. Since the lows of the mid-90s, catch rates for 1999 showed considerable improvement, with the exception of one area that has remained static and another area that has shown a decline. The west coast is particularly important to the rock lobster fishery with over 70% of the total catch coming from west coast waters. Stock assessment indicates an increase in Statewide catch rate, legal sized biomass and egg production. Current assessments indicate that further stock rebuilding is likely to occur with a total allowable commercial catch (TACC) of 1,500 tonnes but not with a TACC of 1,600 tonnes or higher.
- Management arrangements have resulted in a decline in scalefish fishing effort levels using traditional fishing methods including purse seine, beach seine, and graball net.
Unfavourable news- In the global context, there are concerns about the sustainability and ecological effects of 'industrialised fisheries'. Researchers have estimated that the biomass of large predatory fish is only 10% of pre-industrialised levels and that declines of large predators in coastal regions have extended throughout the global ocean (Myers & Worm 2003).
.- The 2000 assessment suggests that blacklip abalone stocks have declined in two regions of the eastern zone (east and south-east coasts). In addition, size distribution data indicates that the fishery in these two regions was substantially dependent on recruits and that the size limits may be too small to ensure adequate recruitment. To address this, the TACC in this zone was lowered, in order to reduce catches, and size limits within most of the zone were increased, to enhance recruitment.
- While present trends suggest that wild fisheries are in a healthy condition, this situation will only continue with continued protection of natural resources (see, for example, Ecological Condition of Coastal, Estuarine and Marine Habitats).
Uncertain news- Data on populations of non-commercial species is severely limited. Ideally, wild fisheries assessment would include non-targeted species that may be subject to unintended fishing pressure through by-catch. Species, which may not yet have commercial applications, may be important for the general health of marine ecosystems.
- 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. Commercial fisheries with an unknown stock are highlighted in the indicator entitled Total Seafood Catch and Estimated Wild Fish Stocks. These were striped trumpeter, wrasse, calamari, octopus, arrow squid, garfish, flathead, bastard trumpeter, flounder, whiting, barracouta, jack mackerel. Catch and catch rate indicators suggest that the sustainability of the banded morwong fishery, even at current levels of exploitation, is uncertain.
- Since 1997-98, effort in the scalefish fishery is down (except for jigs and dipnet)s. Squid jig effort had increased around one hundred fold over the reference period, reflecting increases in effort targeted at southern calamari and, especially, automatic jig effort targeted at arrow squid. Jig effort has increased to such a large extent because historically catches were very low. The calamari fishery is being actively managed through closures and other management methods.
- There is uncertainty about whether the trends of increasing recreational fishing effort will continue and, if so, the consequences for the sustainability of these fisheries.
- The catch of arrow squid in 1999-00 of over 430 tonne is the highest reported catch of the species from Tasmanian waters. It represented a five-fold increase in catch over the previous year with increased squid jig effort, primarily by automated jig vessels, accounting for the majority of the catch. The catch was concentrated off south-eastern Tasmania and, in particular, Storm Bay. However, the high 1999-00 catch of arrow squid was a one-off event. The fishery is now managed through limited entry.
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