However, protective mesh bags may foul quickly and, to maximise retention and spat growth, weekly replacement of mesh bags should be undertaken. The results show that the presence of a mesh bag around spat culture units may improve retention of spat by between 18–41%. Weights than those from the REPLACE treatment. Mean wet weight of the mesh bags at the end of the experiment differed between treatments with bags from the WASH and NO WASH treatments having significantly greater mean wet Grading of the spat from each treatment at the end of the experiment showed that the REPLACE treatment had the highest number of spat in large and medium size classes with mean (± SE) dorso-ventral height of 23.9 ± 0.5 mm and 17.4 ± 0.5 mm, respectively. Culture units in the REPLACE treatment had the greatest number of spat at the end of the experiment and 41% more spat than in the REMOVE treatment. It assessed spat retention and growth in culture units without mesh bags (REMOVE) and in those where mesh bags were replaced weekly (REPLACE), washed weekly (WASH) or left unwashed (NO WASH) for the duration of the six-week experiment. This study examined the effectiveness of mesh bag covers on culture units for spat of the blacklip pearl oyster, Pinctada margaritifera. We conclude that experiments should be conducted to identify optimal materials for collecting the target species of pearl oyster and that collectors should not be placed in protective mesh bags in environments similar to those of Solomon Islands.Hatchery produced pearl oyster spat are generally transferred to the ocean on spat collectors which may, or may not, be covered with fine mesh to prevent spat loss. The bags also fouled easily, impeding waterflow to the collector. Oyster mesh cover being stapled into place to protect oyster spat mesh bags secured in place in tra Stanway. To minimise the risk of damage to the mesh spat bags and loss of spat, the trays should have a suitable plastic oyster mesh cover stapled into place as shown in Figure 6. gastropods and portunid crabs settling to the collectors from the plankton. mesh bag, enabling the bag to be used a number of times. Mesh bags trapped predators such as Cymatium spp. The oyster mesh bag can be used as spat netting to breed oyster spat. The oyster mesh bag can gather the oysters together and raise the production of oysters. Collectors inside protective mesh bags did not yield more pearl oysters than those left unprotected. The oyster mesh bag is mainly used in the growth period of oyster, it can protect the oysters from predators and birds. maculata were more abundant on the plastic sheeting. margaritifera were found on the shademesh, whereas live P. As the seed oysters grew, they were transfe1ed to larger mesh bags up to 3/8. maculata, together with the numbers of predators associated with the collectors. 4-6 mm oyster seed were purchased from Middle Peninsula Aquaculture in. margaritifera, and another pearl oyster, P. We deployed 40 spat collectors at 15 sites within the open reef complexes of Solomon Islands to test the effects of different collectors (constructed of shademesh and plastic sheeting) and protective mesh bags on the abundance of spat. Oyster Spat We plan to overwinter and carry a small amount of spat (both diploids and triploids) over the winter months for pickup on an appointment basis. Refining techniques for the collection of spat is important to the culture of blacklip pearl oysters, Pinctada margaritifera, especially where the collection of spat is marginally effective.
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