Pacific oyster, Magallana gigas


Short description of Magallana gigas, Pacific oyster

Variable and irregular in appearance.  Off-white to yellow or bluish grey in colour, often with deep purple patches.  Grows up to 30 cm in length with a teardrop shape and rough shell.  The right valve is deeply cupped with six or seven bold ribs; the left valve is flat or slightly convex.

Description of Magallana gigas, Pacific oyster status in GB

Farmed at several locations around the GB coast and estuaries.  Escapees have established populations in various locations in the south of England.

Habitat summary: Magallana gigas, Pacific oyster

Lives permanently attached to any hard substrate in intertidal and shallow subtidal zones of estuaries and coastal waters.  In muddy or sandy areas Pacific oysters will settle on small rocks, shells or other oysters and can create reefs by cementing their shells to each other, forming dense layers.

Overview table

Environment: Marine
Species status: Non-Native
Native range: Kazan-retto, Ogasawara-shoto
Functional type: Filter-feeder
Status in England: Non-Native
Status in Scotland: Non-Native
Status in Wales: Non-Native
Location of first record: River Blackwater, Essex
Date of first record: 1926

Distribution map

GB Distribution from NBN Atlas

Author's name:

Natalie Sweet

Last updated:

January 6th, 2012

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