Development and implementation of a national standard for a recreational fisheries database by all fisheries agencies
Developing jungle perch fingerling production to improve fishing opportunities
Jungle perch once occurred widely in coastal Queensland rivers, from Cape York to Northern NSW. Central and southern populations have declined or become locally extinct due to dams and weirs blocking migration pathways between saltwater (where they spawn) and freshwater habitats (where they reside as juveniles and adults). Unlike barramundi, mullet and bass; jungle perch cannot persist long-term in saltwater habitats. Barriers lead to rapid local extinction. Construction of fishways on barriers in the past 10 years has created suitable conditions for the reintroduction of jungle perch. There are limited opportunities for natural recolonisation, and remnant adult populations of local strains are too few for translocation to be a practical solution. Restocking from captive bred individuals is the only option to bring back jungle perch fisheries.
Restoring wild jungle perch fisheries is a high priority for recreational fishers in Queensland. Reintroduction of self sustaining populations in rivers in south-eastern Queensland and the Mackay-Whitsunday Region will provide angling opportunities to large populations of anglers. Development of jungle perch fingerling production will also create future opportunities to further enhance Queensland's stocked impoundments and make jungle perch accessible to even more anglers.
Recent research by DEEDI has solved much of the reproductive biology of jungle perch, which can now be spawned regularly in captivity. Jungle perch larvae are much smaller (2.3 mm) than bass and barramundi larvae and establishment of first feeding has been problematic. Strategies to promote larval feeding need to be developed. The transition from larvae to fingerlings is critical for future development of jungle perch fisheries.
Final report
This project has for the first time demonstrated the feasibility of hatchery production of jungle perch fingerlings. The research on jungle perch production has enabled a hatchery production manual with accompanying videos to be produced. This has given private commercial hatcheries the information needed to produce jungle perch fingerlings. Several hatcheries have already indicated an interest in producing jungle perch and will be assisted to do so in 2016. Currently jungle perch are not a permitted stocking species, so cannot be sold to fish stocking groups. However, hatcheries will be able to sell fingerlings to the aquarium trade or supply grow out facilities that could produce jungle perch for human consumption. Should jungle perch become a permitted species for stocking, this will provide hatcheries with a major new product option to sell to fish stocking groups. It would also benefit anglers by providing another iconic species for impoundment stocking programs. This could have flow-on benefits to regional economies through angler tourism.
Should the pilot reintroductions of jungle perch into streams result in self-sustaining jungle perch populations, then there will be three restored jungle perch populations close to major population centres. This will create a new opportunity for anglers not normally able to target jungle perch. Since the majority of anglers who target jungle perch are catch and release fishers, angling is expected to have minimal impact on recovery of the populations.
This project led to the development of a hatchery manual for jungle perch production and to a summary brochure. In late 2014 and in 2015 researchers were able to make the first ever releases of jungle perch fingerlings back into rivers and streams within their historical range.
Keywords: Jungle perch, Kuhlia rupestris, hatchery production, restoration, fish stocking, captive breeding, larval culture, recreational fishing.
Freshwater fish attracting structures (FAS): Evaluating a new tool to improve fishing quality and access to fisheries resources in Australian impoundments
Reduction of toothed whale interactions with fishing gear: development and assessment of predation mitigation devices around longlines
Predation by toothed whales on fish hooked by longline and dropline gear is becoming more prevalent throughout Australian waters. The duration of the predation period appeared to be seasonal in the north-western Coral Sea fishery during the 1980's. However over recent seasons the duration of the mammals’ presence in the Coral Sea appeared to increase and observations of adults teaching young animals to predate on hooked fish became common. Predation by toothed whales in the Falkland Island Patagonian toothfish fishery appears to be a learned response with the problem dramatically increasing from a short seasonal problem prior to 2001, to a full season problem in 2002.
The development of a combination of predation mitigation methods is urgently required. Losses to the fisheries due to predation, and the increasing likelihood that mortality to mammals may occur with resultant poor publicity for the fishery and increased scrutiny of biodiversity and sustainability issues, necessitate immediate action. Predation by toothed whales in the eastern, southern and western Australian longline fisheries is expected to increase. Apart from an informal review of SENTMAC operations in the blue-eye trevalla fishery by Tasmanian Parks and Wildlife (Rosemary Gales, pers. comm.), no fisheries data are available for the incidence of predation issues by toothed whales in Australian waters. The AFMA Observer Program has commenced monitoring of all forms of predation damage in Australian fisheries, including seals, sharks and toothed whales.
Terminal stage predation events in the north-western Coral Sea fishery have only recently been observed as mammals appear to have become less apprehensive about approaching fishing vessels. The nature of the predation evidence on the fish is now more varied in the Coral Sea than in the mid-1980’s when it was first reported. This suggests that more than one species may be involved, each with its own characteristic bite pattern (McPherson et al. 2003). Whether the terminal stage of each event is acoustic, visual, or a combination of both is not known. Observations of the method of approach of the mammals during predation events, would assist in the development of appropriate mitigation and gear modification methods.
Predation has been increasing on marlin hooked by the Cairns-based game fishery. Predation is now occasionally reported by smaller toothed whales such as dolphins (family Delphinidae) from coastal fisheries (including Queensland waters) and is likely to increase in commercial and recreational fisheries all State waters as it has in coastal Hawaiian waters.
At the Queensland Fisheries Service (QFS) "Invitational workshop on acoustics to reduce marine mammal interactions" Brisbane April 2002, the keynote speaker Prof Jon Lien (Chair of Ministers Advisory Committee on Fisheries and Oceans, Canadian Minister of Fisheries and Oceans) brought to Australia by NHT funding indicated that predation issues are now reaching extreme levels in at least a dozen countries. No research was being conducted on predation issues, and there was no clear certainty within fisheries circles about what research to conduct.
While the mammal predation issue does not pose a major threat to the continuation of the longline fishery, there is real concern that mammal interaction issues may not be considered on a scientific basis. Bache and Evans (1999) pointed out that while Australian fisheries albatross bycatch policy was influenced by scientific data, environmental non-government organisations (NGO’s) were instrumental in determining Government dolphin bycatch policy. Policy development catalysed by NGO action was considered by Bache and Evans (1999) as least likely to achieve consensus resolution. Commonwealth and State fisheries policy would best be served by achieving consensus resolution through scientific monitoring of the interactions.
Interaction problems are not restricted to economic returns to the fishery and direct threats to the well being of toothed whales. Increasing predation rates reflect a probable change of diet for some species. Based on interactions between dolphins and some trawl fisheries, there could also be a disproportionate population increase of some species that would put many animals under threat if fishing effort, hence opportunities for predation, were to reduce.