These had an average weight of 9.91 g when collected and were placed in Nestier trays suspended on a long line (Figure 2). For Pinctada Margaritifera oysters in French Polynesia this time period usually ranges between 12 and 24 months. corteziensis were collected from mangrove roots in the Tachichiltio area on October 19, 2008. Pearl farmers must wait and care for oysters until they reach a grafting size. Substrate materials for oyster and mussel may be used as spat collectors. Exo Environmental are working towards an innovation that reduces commercial risk to native flat oyster production whilst also improving productivity. Spat collection is the most critical part of the operation. Its culture is divided into two stages: (1) spat collection and (2) growing or culture.
This ensures that the wild oyster stocks are not depleted and gives farmers access to strong adult oysters that can be used for cultured pearl production.Īn oyster must reach a certain size before it can be operated in order to induce the birth of a cultured pearl. The culture cycle of oyster and mussel is a year from spat collection to harvest. In areas of Australia, adult wild oysters (of specific sizes) are collected under a strict quota system regulated by government. Whilst in French Polynesia nature permits Pinctada Margaritifera oysters to be collected at a juvenile stage ('spat') in the wild, in other areas where oyster reproduction is insufficient or qualities are not high enough oyster hatchery programmes are used. The bars are 1.2m in length, weigh 1.5kg and have a diameter of 143mm. The perforated version are particularly used with flat oysters. The condition varies in different countries. These collectors are perforated and are used in the collection of both gigas and edulis spat.
One is to collect them in the wild, the other is through oyster breeding programmes in hatcheries. Sold individually, hatchery oyster spat requires less work and labour. Juvenile pearl oysters can be obtained in two ways. Unlike natural collection, hatchery spat production is a continuous process.
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