The fertility of the Port Lincoln oyster ( Ostrea angasi Sowerby) from West Lakes, South Australia

Abstract

During 1977–1978 the spawning season of the Port Lincoln oyster ( Ostrea angasi Sowerby) extended from about mid-October to early March. Between 5.6% and 21.4% of randomly sampled adult oysters (larger than 68 mm in length) were incubating larvae and between 0.91 and 1.33 broods of larvae were produced per adult oyster. Large oysters (68–94 mm in length) had a mean of 12.1 × 10 5 larvae per brood. The incubation period under natural and laboratory conditions ranged from 15–22 days and there are similarities in the breeding biology of O. angasi, the European oyster ( Ostrea edulis L.) and the Olympia oyster ( Ostrea lurida Carpenter).