Evizel Seymour

Evizel Seymour has been involved in Aquaculture for over 20 years, working in research and industry. Her initial introduction into aquaculture was with silver perch and Murray cod in central NSW, then moving into developing a goldfish farm in WA. She then ventured into the marine world of mahi mahi, seacucmbers, giant clams, black lip pearl oyster and prawns. She has a thorough knowledge of marine hatchery design, (including live foods), setting up hatcheries in SI, Hawaii and Australia in both research and industry fields. A major component of her work has involved training staff to run the hatcheries and facilities.Under construction

She is now project leader of the FFAC (Freshwater Fisheries and Aquaculture Centre), DPI&F at Walkamin, where research is directed at using aquatic plant remediation of wastewater of intensive production of Barramundi and developing aquaculture in PNG with native species.

Presentation

Can we really produce fish with zero discharge of water?      Yes!

With the use of aquatic plants in a process called bioremediation.  

Bioremediation uses aquatic plant species (Lotus and Duckweed) to trap sediment and improve water quality by utilising the nutrients in a treatment pond then returning the water back to the production pond (Barramundi). These trials are being carried out at Walkamin Research Station in conjunction with an industry partner, Daintree River Barramundi.

On-farm sites bioremedation will limit water discharge and reduce the reliance of fish farms on environmental extraction of water. This system aspires to eliminate the need to discharge water while increasing the carrying capacity of farms. In a two year production cycle (those producing 2kg+ fish) there is a high economic loss of crop due to pond crashes in the second summer, when nutrients in bottom sediments are mobilised during anaerobic conditions following thermocline establishment. Lotus & duckweed bioremediation addresses these issues, through a low cost option for maintaining and improving water quality and utilising nutrients in the bottom sediments before they can be released.      

The major aim of this project is to reduce or remove negative environmental impacts of current water management practices using aquaculture. As such it will promote positive environmentally significant actions. These actions will reduce the amount of effluent and nutrients currently entering natural watercourse, reduce the amount of water extracted from natural watercourses for production uses and reduce need to control predatory species of birds and animals due to more intensive management permitted in production areas. The native species are being used to avoid potential negative impacts of translocation of potentially weedy species. This research aims to negate the environmental impacts associated with high production aquaculture while having major efficiency and production improvements.