Pearl oysters Pinctada margaritifera grazing on natural plankton in Ahe atoll lagoon (Tuamotu Archipelago, French Polynesia).

In atoll lagoons of French Polynesia, growth and reproduction of pearl oysters are mainly driven by plankton concentration. However, the actual diet of black-lip pearl oysters Pinctada margaritifera in these lagoons is poorly known. To fill this gap, we used the flow through chamber method to measure clearance rates of P.

Influence of plankton concentration on gametogenesis and spawning of the black lip pearl oyster Pinctada margaritifera in Ahe atoll lagoon (Tuamotu Archipelago, French polynesia).

Pearl culture industry represents one of the dominant business sector of French Polynesia. However, it still entirely relies on unpredictable spat collection success. Our aim was to assess the influence of natural plankton concentration fluctuations on maturation and spawning of the black lip pearl oyster Pinctada margaritifera, during a 4 months survey conducted in Ahe atoll lagoon.

Multi-scale distribution and dynamics of bivalve larvae in a deep atoll lagoon (Ahe, French Polynesia).

Bivalve larvae and hydrographic parameters were sampled over a range of spatio-temporal scales in a deep atoll lagoon. Bivalve larvae abundances were very high throughout the year: 18,550 m(-3) in average. Larvae were (i) concentrated at mid-depth with nocturnal ascent and diurnal descent, (ii) heterogeneously dispersed at the lagoon scale, (iii) subject to day-to-day variation in abundance and (iv) transferred between different parts of the lagoon providing evidence of intra-lagoonal connectivity.

Motility activation and metabolism characteristics of spermatozoa of the black-lip-pearl oyster Pinctada margaritifera var: cumingii (Jameson, 1901).

Motility of Pinctada margaritifera (Linnaeus, 1758); var: cumingii (Jameson, 1901) (P. margaritifera) spermatozoa collected from gonads are not immediately activated at spawning in seawater (SW) but motility occurs when spermatozoa are transferred into alkaline seawater (pH ranging from 9.0 to 11.

Reproductive and larval cycle of the scallop Argopecten purpuratus (Ostreoida: Pectinidae), during El Niño-La Niña events and normal weather conditions in Antofagasta, Chile.

Seasonality, amplitude, and magnitude of spawning events were determined for Argopecten purpuratus in the La Rinconada marine reserve, Antofagasta, Chile, between December 1995 and January 2004. During the same period, samples of scallop larvae were obtained in vertical plankton hauls recovered within this reserve in an area routinely exposed to circular, gyre-like currents which helped retain the larvae within the bay. The reproduction of this population in normal or cool (e.