D. C. Harris, L. M. Joll, R. A. Watson, (1999). “The Western Australian Scallop Industry,” Fisheries Research Reports No. (Fisheries Western Australia, Perth, Australia
Five separate commercial fisheries target the saucer scallop, Amusium balloti (Bernadi 1861) in Western Australian waters. While the average annual catch from these fisheries is around 600 tonnes of scallop meat, past catches have been highly variable with annual landings ranging from 150 to 4,400 tonnes of meat worth between $2 and $59 million. Consequently, scallops represent one of the larger single-species fisheries operating in Western Australia (WA). A. balloti has a distribution spanning most of the WA coast, from Broome in the north around to Esperance in the south. Despite this extensive distribution, saucer scallops tend to be restricted to areas of bare sand in the more sheltered environments found in the lee of islands and reef systems, and are consequently found in commercially viable amounts in only five locations in WA. The five WA fisheries that target scallops (with average annual landings in brackets) are: the Shark Bay Scallop Managed Fishery (541 t), the Abrolhos Islands and Mid-West Trawl Managed Fishery (121 t), the south coast (15 t), the South-West Trawl Managed Fishery (11 t), and the Nickol Bay Prawn Managed Fishery (4 t). The majority of the annual catch is exported as frozen scallop meat to Asia, Europe and the United States of America, while a small portion is marketed directly to the public via local retail outlets. As with catches, wholesale market prices have fluctuated dramatically over the last 10 years, plummeting from $16/kg in 1987 to $8.50/kg by 1991, before steadily improving to peak at $28.50/kg in 1995. This variation has arisen primarily in response to product availability and condition. The primary scallop fisheries operate in Shark Bay and around the Abrolhos Islands. Commercial fishing commenced in these fisheries in the late 1960s with moderate catches reported. Following a period of low catches in the mid 1970s, landings increased significantly during the late 1970s and early 1980s, mainly due to increased recruitment and fishing effort. Further advancements in processing methods and marketing strategies, and an associated increase in profitability, attracted even more vessels to the fisheries with further increases in effort. Subsequently, both were declared limited entry fisheries (now termed Managed Fisheries under the Fish Resources Management Act 1994). The Abrolhos Islands and Mid-West Trawl Fishery and Shark Bay Scallop Fishery were declared limited entry fisheries in 1986 and 1987 respectively. As A. balloti is an active swimmer, otter trawling is favoured. Vessels fishing for scallops in WA employ demersal otter trawl gear with strict controls placed on the vessels (boat units) and associated trawl gear (size restrictions) that can be used in each of the fisheries. These controls are designed to limit the total fishing effort to acceptable levels in order to maintain adequate spawning stocks, and to target those scallops at a size and age when the meat is in a premium condition for market. Research into the biological and environmental aspects of WA scallop stocks and their commercial exploitation has been carried out by Fisheries WA since the late 1960s. This research has centred on maximising the economic returns from the available scallop resource, while managing its use and harvesting at ecologically sustainable levels. Research initiatives have included pre-season surveys to monitor the strength of recruitment to seasonal scallop stocks, the monitoring of environmental influences, such as the Leeuwin Current, and their effects on scallop populations, and the provision of detailed catch data via voluntary logbook programs and statutory monthly fishermen’s returns.