The collection of natural spat in relation to the natural fishery, potential maricultural activity and the recreational fishery is discussed. Juvenile oyster spat recruit to the adult oyster shells and settle. The shift in recruitment patterns over time is partially attributed to increased subtidal predation pressure on the recruits. a method for measuring interstitial space of the concrete artificial oyster reef. The monthly samples had higher numbers of oyster spat at the mean low water mark while the seasonal samples showed significantly higher recruitment intertidally (up to x − = 7353 spat m −2). The biweekly samples generally experienced higher recruitment subtidally at the three sites. The least sheltered site had the lowest numbers of young oysters ( x − = 1000 spat m −2 BW x − = 686 spat m −2 M), as well as having the most stable temperature regime. This site also had higher overall water temperatures as well as greater daily temperature fluctuations. The most sheltered site in terms of wave exposure experienced the highest recruitment ( x − = 4380 spat m −2 BW x − = 6260 spat m −2 M). The intensity of recruitment varied significantly among the three sites. The levels of recruitment were very high relative to other regions on the east coast of the USA, with peak recruitment for the entire study area ( x − = 2800 spat m −2 for BW and x − = 3020 spat m −2 for M) occurring between July and September. The results indicated that the recruitment of oysters in this region of coastal Georgia is protracted, lasting 6 months (May through October). Sampling took place so as to measure net re cruitment over biweekly (BW), monthly (M) and seasonal (S) periods. In June, spat collectors were placed at five locations along the estuary's salinity gradient and near potential restoration sites. Within each site, oyster recruitment was estimated at three tidal heights subtidally, at mean low water and intertidally, approximately 2 h above the mean low water mark. Five spat collectors were constructed by attaching a weighted string of clean oyster shells to a bouy so that the collectors hung near the bottom of the water column. The sites varied in terms of temperature and salinity regimes and in their exposure to wind and wave action. Three sites of varying hydrographic characteristics were chosen in Wassaw Sound. One of the goals was to determine the most suitable time for the collection of natural spat for maricultural, fisheries and recreational purposes. The study was initiated to determine precise recruitment patterns of oysters over the 7 month spawning season. This study highlights the advantages of augmenting habitat in a manner that provides vertical relief from sedimentation.Oyster recruitment was monitored in Wassaw Sound, Georgia from April through October, 1991. Collectively, the data suggest that building thicker shell beds might increase the longevity of a constructed shell bed, and therefore, this approach is recommended for future restoration activities in southern California. lurida oyster density compared with unmanipulated plots and increased oyster density relative to the average density of oysters measured elsewhere in Newport Bay. Overall, augmenting mudflat habitat with oyster shell significantly increased adult O. There was no significant effect of shell deployment method on shell cover, recruitment, or adult density however, spatfallwas greater on loose shell beds comparedwith bagged shell beds in the final year of the study. Shell cover, oyster spatfall (settlement), oyster recruitment, and adult oyster densities were analyzed over 2 y 12-cm-thick oyster beds maintained higher shell cover, experienced less sedimentation, and received greater numbers of oyster recruits than 4-cm-thick beds. Replicate ( n = 5) 2×2 m shell beds were constructed of two initial shell planting thicknesses (bed thicknesses of 4 versus 12 cm) and two methods of deployment (bagged versus loose shell). Several commonly used oyster restoration techniques were examined to determine which would be the most successful for restoring the Olympia oyster Ostrea lurida in Newport Bay, CA. Worldwide oyster population declines have been dramatic and efforts to restore declining populations and the services they provide are ongoing. Oysters provide habitat, sediment stabilization, and improved water quality, and are important foundation species in many estuarine ecosystems.
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