Management problems in mussel farming

Abstract

Mussel farming can provide an alternative to the fluctuating supply of wild mussels. Cultivation on suspended ropes facilitates not only continuity of production but also faster growth, a better product, lower mortality, fuller use of the water column and the use of previously unproductive areas. The biological requirements for a successful industry are met by the rapid growth, adequate reproductive capacity, high density and good quality of both of the two common New Zealand species, the green-lipped mussel Perna canaliculus and the blue mussel Mytilus edulis aoteanus. The hydrographic requirements for sheltered water with suitable temperature, salinity and turbidity presents no problems. Socio-economic requirements however are more complex. The established internal market is based on large130 mm mussels whereas 80 mm mussels could be produced more economically. The “alternative use potential” of proposed mussel farming areas for fishing, navigation and recreation must be considered as well as the use of adjacent shoreline. Practical problems faced by mussel fanners include the provision of flotation, acquisition of seed mussels, fish predation, over-crowding and localised pollution. Bulk harvesting of the 80–100 mm mussels after the 14–18 month growth period, whilst they remain in peak condition, is a problem that will require increased mechanisation within the industry.