The collectors were made of: 1- oyster shells, 2- PET bottles, 3- car tires and 4- tiles, all of them suspended by ropes and tied to roots of Rhizophora mangle or mussel long-lines. at five sites in the Benevente river estuary, Anchieta District and on two islands in Piúma District, both in Espírito Santo State. This paper evaluated the effectiveness of four types of oyster spat collectors, made with recycled materials, in the recruitment of the mangrove oyster Crassostrea spp. Data suggest that maximum recruitment in this area is most likely to occur on both collector types between May and mid-June. Barnacles (Balanus sp.) settled on both collector types in high numbers throughout the study. Spats larger than 10 mm were found on the second or third sampling date in each group for both oyster and mussel shell collectors. Spat recruitment varied considerably between collector types as well as between the outsides and insides of shells (p<0.05). The recruitment levels were highest in the groups deployed on June 16, with 40 oyster spats collected on the oyster and mussel shell collectors, respectively. Five groups of each type of collector were deployed from May to August. Oyster and mussel shells were used as substrates in spat collectors. The aim of the study was to determine the recruitment pattern for six months and the most suitable time to collect oyster spat from nature. Oyster recruitment was monitored in Karantina Island near Izmir, Turkey, from May to October 1999. We also suggest experiments with collectors conditioned with adult Crassostrea gasar shell remnants, as well as those where limited establishment of epibenthos, such as barnacles, has been allowed, in order to maximize spat collection of the target species, C. The timing and location of seed collection is therefore critical. Knowledge of the timing and density of settlement of this oyster and associated epibenthos is important in order to minimize interference during seed collection of target species. Seed is regular and abundant as densities exceed published figures for several other Crassostrea species. canela, the larvae of which appear to prefer high salinity. Oyster growers are concerned about potential impacts of Crassostrea sp. The target species for oyster culture in Pará is Crassostrea gasar. However, in the dry season, seed predominated on the inside of bottles, a refuge from predation or desiccation or both, whereas oyster scars and barnacles were more abundant on the outside. Oyster seed and barnacles on sheets were more abundant in the wet season. Although densities of other epibenthos were low and irregular, these were positively correlated with densities of seed on both collectors. Seed and scars predominated (>95% relative abundance) on both collectors. canela on bottles were about half those on sheets. Densities of seed and scars of Crassostrea sp. canela) that is closely related to Indo-Pacific Crassostrea and that also occurs in southern China. The only oyster species found settling on the substrates was a possibly exotic oyster (Crassostrea sp. Densities of oyster seed, scars and other epibenthos on plastic sheets and bottles were observed over two years at a mangrove island (Ilha Canela), Bragança, Pará, northern Brazil. Management and culture of mangrove oysters may reduce harvesting pressure on natural populations in northern Brazil. Please support the Brazilian Journal of Aquatic Science and Technology by downloading from their site: In this area is most likely to occur on both collector types between May and mid-June. Barnacles (Balanus sp.) settled on bothĬollector types in high numbers throughout the study. Spats larger than 10 mm were found on the second or third sampling date inĮach group for both oyster and mussel shell collectors. Varied considerably between collector types as well as between the outsides and insides The recruitment levels were highest in the groups deployed on June 16, with 4069 andġ575 oyster spats collected on the oyster and mussel shell collectors, respectively. Five groups of each type of collector were deployed from May toĪugust. Oyster and mussel shells were used as substrates Suitable time to collect oyster spat from nature. The aim of the study was to determine the recruitment pattern for six months and the most Oyster recruitment was monitored in Karantina Island near Izmir, Turkey, from May to Octoberġ999.
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