Upper slope dogfishes have been suggested as an alternate resource that could be harvested by some sectors of the SSF; some operators are already targeting these species and this is likely to increase in the future. If ITQs are introduced in the SSF, fishers are likely to have an incentive to target species not under quota control. The dogfish resource is likely to receive increased attention from shark fishers under ITQs and the fact that it is a targeted fishery suggests it could become rapidly over-exploited if no catch controls are introduced. Deep-water dogfish are also caught by trawl, both in the SET and the Great Australian Bight (GAB), and are also taken by dropline. Agreement needs to be sought between sharkMAC, SETMAC, GABMAC and the SEFNTCC on appropriate management of dogfish (Future management options for the Southern Shark Fishery - a report prepared for AFMA by FERM). The five year strategic plan for the SSF incorporates projects on alternate resources, although they are currently listed as a low priority. However, as noted by the Southern Shark Fishery Assessment Group (report to SharkMAC from SharkFAG 24.4.1997) an implication of introducing quotas into the SSF is that there are inadequate data for stock assessment of species other than school and gummy shark.
Trawl surveys of the outer shelf and upper slope off New South Wales have documented a very significant reduction in catch rates of squalid sharks over the last 20 years (Ken Graham, NSW Fisheries Research Institute, personal communication). There is also anecdotal information from fishermen targeting dogfish in New South Wales and Western Australia that catches have declined in the original fishing areas. Evidence from other regions where these deep-water species are fished for their liver oils such as the Philippines, New Guinea and the Azores suggests that local populations can be fished down relatively quickly.
It is possible that deep sea squalid sharks have, because of their suspected low productivity, declined to a similar extent to the orange roughy stocks, now 10-20% of initial levels. This raises the question of the sustainability of present catches. Dogfish are an important component of the deep-water ecosystem and under the Federal Fisheries Act AFMA has a stated objective to manage Commonwealth fisheries in accordance with principles of ecologically sustainable development (ESD). AFMA sees this objective as requiring it to manage fisheries so as to minimise the impact of fishing on biological diversity and ecosystem habitat.
