Pecten novaezealandiae, or the New Zealand scallop, is a bivalve mollusc of the family Pectinidae.

Distribution

Pecten novaezealandiae is endemic to New Zealand. It is found in the North Island, South Island, Stewart Island, and the Chatham Islands.

Habitat

Pecten novaezealandiae is found in sand, silt, and mud from low tide level to over 90 m. Large populations are found at depths of between 10 to 25 m. .

Introduction

Pecten novaezealandiae is completely free living, and therefore mobile and somewhat migratory . The two valves are asymmetric. The left valve is convex while the right is flat. The concave valve has approximately 16 ribs . The colour is variable, however the valves are usually a whitish pink, but sometimes can be a dark reddish brown. Natural predators are starfish and octopuses .

Life Cycle

Sexual mature individuals are hermaphrodites. They are broadcast spawners. The season when the organisms spawn is variable between locations. However in Tasman Bay the peak time is between November to March . Fertilisation occurs and a platonic larvae forms. This life stage is conserved for approximately three weeks. Metamorphosis occurs and the larvae changes from planktonic to a benthic existence by attaching itself to suitable substrate on the seafloor. The attachment lasts until the individual is at least five millimetres long. The individual then detaches from the substrate and begins to grow into an adult. Maturity is usually achieved by 18 months.

Fisheries

The New Zealand scallop is a large industry and export product of New Zealand. The large white adductor muscle is eaten, sometimes the yellow gonad is often eaten as well. P. novaezealandiae is considered a fine food and can be expensive to purchase. Recreational and commercial fishing of this species is allowed at particular times of the year, this is called scallop season. The size and number of scallops which can be caught are under control of the quota management system. In some areas of suitable habitat, such as Tasman Bay scallop spat is seeded. This is an attempt to achieve a sustainable fishery.

External links

• Scallop enhancement aquaculture
• Sealord farming information
• Tasman Bay map of scallop enhanced areas

References