- Say No
- Yellowtail kingfish is caught in the NSW Ocean Trap and Line Fishery. The stock status is defined as 'growth overfished' in fishery reports, meaning large fish have been fished out, and those being caught are too small to maintain the population in the long-term.
- There are also significant concerns about threatened and protected species bycatch from this fishery. Critically endangered grey nurse sharks have been caught, as well as endangered great white sharks and green turtles.
- Sharks caught incidentally can be retained for sale. The limit set by fishery managers on the amount of sharks that can be kept is not based on scientific assessments of the stock status of affected shark species, as there is limited information on the population status of many sharks.
- NSW Ocean Trap and Line Fishery (~125t 2008-09)
Yellowtail kingfish is caught in the Ocean Trap and Line Fishery (OTLF) in NSW using a variety of line methods, including handline, set line and driftline. Yellowtail kingfish is also a key target for recreational fishers. The stock status is defined as ‘growth overfished’ in fishery reports, which means that the larger, reproductively mature fish have been already fished out, and those currently being caught are juvenile fish. In this situation, the long-term sustainability of the species and therefore the fishery is in doubt.
The bycatch of threatened and protected species associated with the fishery is also a main concern. Hammerhead sharks, which are listed as protected under NSW legislation, are caught and killed in the fishery, as well as endangered grey nurse and great white sharks and green turtles.
Sharks that are not listed as protected under Federal or NSW State law can be retained for sale, including sandbar and dusky sharks. These sharks are large, slow to mature and late to reproduce, meaning they are extremely vulnerable to fishing pressure. Although fishery managers have set limits on the number of sharks that can be retained, these limits are not based on scientific assessments of the stock status of affected shark species, as there is limited information on the population status of many sharks.
Accessing information from this fishery has proved difficult. Many of the stock assessments and information on shark catches is from fisheries information from 2008-09.
- Say No
- Yellowtail kingfish are farmed in sea cages off SA. Broodstock (fish eggs) are produced in hatcheries and grown out in the ocean.
- Yellowtail kingfish are highly mobile, carnivorous predators and require large amounts of wild-caught fish in feed. Yellowtail kingfish aquaculture uses considerably more wild fish than is produced through farming.
- Localised impacts from yellowtail kingfish farming effluent are minor and short-lived. The environmental impacts of a projected tripling in production on a broad ecological scale are not clear.
- There is limited information on threatened species interactions, although there are some suggestions that dusky whaler and great white sharks damage sea cage nets.
- SA (500t per year)
Yellowtail kingfish is farmed off the coast of SA in sea cages. There have been investigations into the feasibility of yellowtail kingfish aquaculture in NSW and WA, with both states hoping to begin farming in coming years. Broodstock (fish eggs) are produced in hatcheries and grown out in the ocean.
Public reporting on the impacts of yellowtail kingfish farming in SA is limited to studies of direct environmental effects from fish waste; for example, producers do not provide detail on the amount of wild fish required to grow farmed fish. Information from scientific reports identifies a high dependency on wild-caught fish for use in fish feed, with approximately 3kgs of wild-caught fish required to produce 1kg of yellowtail kingfish, which means yellowtail kingfish aquaculture actually uses considerably more wild fish than is produced through farming. This places a high burden for wild caught resources on the marine environment. Research currently underway into alternative sources of feed materials for carnivorous farmed fish could reduce this dependence in coming years.
Yellowtail kingfish are farmed in sea cages that are open to the ocean, and any waste from the farm is washed into surrounding water. The effects of waste have been studied on the areas surrounding sea cages and impacts appear to be minor and short-lived on seafloor dwelling species. The sea cages are sited in areas with high water movement, so waste is flushed away at regular intervals.
There are intentions to triple production of yellowtail kingfish in SA in coming years. The environmental impacts of this increased production on a broad ecological scale are not clear.
There is limited information available about threatened species interactions with farming operations, although there are some suggestions that dusky whaler and great white sharks damage sea cage nets.