People development program: 2014 FRDC International Travel Award - Dr Ben Doolan
Inland fish stocking programs in NSW are administered by NSW DPI under the NSW Freshwater Fish Stocking Fishery Management Strategy (FMS) which outlines the rules, regulations and programs for fish stocking. The FMS is due for review in the near future and it is an opportune time to investigate the strategies used by international agencies for the management of their stocking programs. An extensive worldwide network of scientists and fisheries managers will be in attendance at the FSBI conference in Hull and it will be most beneficial to gain exposure on an international scale, obtain up to date information and share perspectives on inland fisheries management with experts from international agencies. In addition to attendance at the conference, I have made contact with several staff members from the Environment Agency and the Angling Trust to gain further insights into the management of inland fish stocking programs in the UK. I have organised to meet with these experts at various locations including Brampton, Reading and Frimley outside of the conference to gain further exposure and directly observe management practices and perceptions from both Government and non-Government organisations which may be transferable to existing NSW programs and other Australian jurisdictions developing or refining stocking policies. The project will assist in bridging the gap between management and research by potentially identifying key research priorities for stocking programs. The project will importantly enhance my international presentation, networking and analysis skills which are essential for my development as a future leader in fisheries management.
Description of the biology and an assessment of the fishery for adult longfinned eels in NSW
Internationally, the demand and resulting value of glass eels has increased tremendously in recent years. Live glass eels are now selling for over $15,000 per kilo. This international demand results from over-fishing of adult and glass eels in Asia, North America and Europe. This world experience indicates that recruitment over-fishing of long-lived freshwater eels can be catastrophic. Because of the increasing significance of adult eels in the estuarine fisheries of NSW, decreased catches in recent years and the prospect of increased future catches of glass eels for aquaculture, it is important to undertake research which will lead to an understanding of the current status of adult eel stocks in NSW. Stocks of adult eels must be managed properly to ensure continued production of the commercial fishery for adult eels, continued recruitment of glass eels and elvers for aquaculture and stability of coastal catchment ecosystems.
Limited research into the basic biology and ecology of longfinned eels has been carried out in Victoria and Tasmania, but there have been no biological studies conducted in NSW. The only published age and growth information for this species comes from one catchment in Tasmania and indicates that they are relatively long-lived (40 years), but this age data has not been validated. The available literature indicates that growth rates of freshwater eel species are highly variable among habitats and distributional ranges. Therefore, there is a need to determine the basic biological parameters of NSW longfinned eel stocks, including validated age structure, growth and mortality rates, and reproductive characteristics for use in stock assessment modelling.
Since there is a significant commercial fishery for adult eels in NSW, fishery-dependent techniques based on sampling of commercial catches represent the most cost effective stock assessment and monitoring methodology. Age and growth monitoring of many commercial finfish species in NSW is currently carried out by sampling fish at the Sydney Fish Markets and regional fishermen’s co-operatives. Most of the commercial eel catch in NSW is exported live through a few (currently four) specialised processors. Therefore, it will be necessary to establish a specialised monitoring regime and fishery-dependent model which will provide data on which to base advice for the future sustainable management of exploitation of the resource.