The growth of oysters Ostrea edulis and Crassostrea gigas in Emsworth Harbour

Askew, C.G.

doi:10.1016/0044-8486(72)90026-9

Cited by 32 publications

(4 citation statements)

References 8 publications

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“…This estimate of growing season length was consistent with conditions during this study and previous observations for the mid to northern Atlantic region (Loosanoff and Nomejko 1949;Rheault and Rice 1996;Soniat et al 1998). This estimate is also reasonable given the relatively short period of growth to harvestable size for these estuaries, and because the smaller amount of growth that may occur during the remainder of the year (colder periods) is likely balanced by a reduction in growth with age as bivalves approach legal size and not accounted for in a linear model (Askew 1972).…”

Section: N Removal and Bioremediation Calculationsmentioning

confidence: 87%

Bivalve-enhanced nitrogen removal from coastal estuaries

Carmichael

WaltonWilliam

ClarkHeidi

2012

Can. J. Fish. Aquat. Sci.

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Interest in use of bivalves to remediate estuarine eutrophication has increased in recent years. High variation among data sets, substantial focus on particle removal, and insufficient links to anthropogenic nitrogen (N) sources encouraged this empirical examination of N removal by bivalves from estuaries receiving different N loads. We determined the capacity of the oyster Crassostrea virginica to remove N by comparing N assimilated into tissues with anthropogenic N from land or available in phytoplankton. Oyster growth yielded 0.2-0.4 g N in tissues and depended on estuary-specific conditions. d 15 N values confirmed that N in oyster tissues derived from local anthropogenic sources. At representative restoration and aquaculture conditions (≤400 oysters·m -2 at 0.5%-1.0% of estuary area), estimated N removal was ≤15% of landderived loads and <1% of phytoplankton N. N removal via biogeochemical processes was negligible during grow-out, but became important after oysters attained harvestable size. This study explicitly demonstrates that oysters assimilated landderived N, but suggests that bivalve bioremediation consider trade-offs between intensity of planting, ecological effects, and available space.Résumé : Le recours aux bivalves pour contrer l'eutrophisation estuarienne suscite un intérêt croissant ces dernières années. La variabilité élevée d'un ensemble de données à l'autre, un accent important sur le retrait de particules et l'insuffisance de liens établis vers des sources anthropiques d'azote (N) ont motivé l'examen empirique du retrait de l'azote par des bivalves d'estuaires qui reçoivent différentes charges d'azote. Nous avons déterminé la capacité de l'huître, Crassostrea virginica, de retirer l'azote en comparant le N assimilé dans leurs tissus au N anthropique de source terrestre ou disponible dans le phytoplancton. La croissance d'une huître produit de 0,2 g à 0,4 g de N dans les tissus, selon les conditions propres à l'estuaire. Les valeurs de d 15 N ont confirmé que le N dans les tissus d'huîtres provient de sources anthropiques locales. Dans des conditions de restauration et d'aquaculture représentatives (≤400 huîtres·m -2 sur de 0,5 % à 1,0 % de la superficie de l'estuaire), le taux de retrait estimé de l'azote était de ≤15 % des charges de sources terrestres et de <1 % du N provenant du phytoplancton. Le retrait du N par des processus biogéochimiques s'est avéré négligeable durant le grossissement, mais devenait important après que les huîtres aient atteint une taille commerciale. L'étude démontre explicitement que les huîtres ont assimilé du N de source terrestre, mais suggère que la biorestauration à l'aide de bivalves devrait tenir compte des compromis entre l'intensité de l'ensemencement, les effets écologiques et l'espace disponible.[Traduit par la Rédaction]

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Section: N Removal and Bioremediation Calculationsmentioning

confidence: 87%

Bivalve-enhanced nitrogen removal from coastal estuaries

Carmichael

WaltonWilliam

ClarkHeidi

2012

Can. J. Fish. Aquat. Sci.

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“…Fujiya (1970) and Korringa (1976) have given growth figures for this oyster of 60 g in the first year in Japanese waters, and in Britain. Askew (1972) & Hall (1984 recorded a total weight of 55 and 70 g in 12 and 16 months. Considering somatic production, which integrates the growth and mortality results, production figures have been reported for other cultivated bivalves by Gardner &Thomas( 1987).…”

Section: Discussionmentioning

confidence: 99%

Mortality, growth and somatic secondary production of the bivalve, Pinna rugosa (sowerby), in suspended and bottom culture in Bahia de La Paz, Mexico

1995

Aquaculture Res

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The objectives of this study were the determination of mortality, growth, condition factor and meat yield, biochemical variables, and somatic secondary production of Pinna rugosa (Sowerby, 1835) in suspended and bottom conditions in Bahia de La Paz, Mexico. The use of each of these parameters was analysed as a decision element for managing the resource. The experimental design was based on the recruitment of wild spat on collectors and introducing bivalves of the same size into different areas. In each area, bivalve samples were used both in suspended trays, and lying on the bottom, approximating their natural occurrence, but surrounded by a plastic mesh fence. The stocking densities in both cultivation systems were 50, 100 and 150 m−2. The organisms were checked monthly for almost 2 years, recording various measurements. In one of the treatments that most closely represented the average, the growth values were 19.5 mm month−1 and 14.5 g month−1 in the first year, a length‐growth Von Bertalanffy K of 0.118 and an instantaneus growth rate in weight G of 4.77. During the first year, there was annual mortality of 22% on the bottom and 11% at the surface, with somatic secondary production, in dry weight, of 17.8 g per organism. The results of the estimation of each variable were submitted to a multifactorial anova. NO significant differences in K as a function of sites, cultivation systems or density could be found. The effect of site on instantaneous growth rate G was significant. The largest values were from the inner bay (site 1) where the highest mortality rate also occurred. Among condition factor, meat yield and biochemical components, only lipids showed a difference for systems and site factors. We concluded that secondary production gave statistical elements for the selection and culture decision‐making in all factors tested. The results showed good aquaculture prospects for P. rugosa.

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“…and Euglenophyceae (Eutreptiella marina) (Buchanan 1966). In an oyster culture area in England, Askew (1972) observed a high biomass of Chlorophyceae and Euglenophyceae species and large populations of chlorophyll b rich phytoplankton have been reported in coastal waters elsewhere (Hallegraeff 1981, Vernet & Lorenzen 1987. Incze et al (1980) suggested that nanoplankton may be an important nutritional conlponent of mussel diets.…”

Section: P0mentioning

confidence: 99%

Multivariate analyses of the role of environmental factors in seasonal and site-related growth variation in the Pacific oyster Crassostrea gigas

Brown¹

1988

Mar. Ecol. Prog. Ser.

102

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Monthly increases in shell height were measured for 2 age classes (Years 0 and 1) of a common broodstock of oysters Crassostrea gigas in 10 locations in British Columbia, Canada, over 14 mo. Measurements were also taken of several environmental variables known to affect oyster growth. Based on comparisons of shell height growth curves, sites were grouped into low, medium and high growth categories which were similar for both age classes of oysters. According to discriminant function analysis, differences in salinity and particulate organic matter (POM) concentration distinguished low growth sites from medium and high growth areas. Medium and high growth areas were segregated solely on the basis of food-related var~ables: POM, carotenoid concentration and Secchi depth. In multiple regression analysis, chlorophyll b concentration and water temperature were significantly correlated (for both age classes; l2 = 0.34, p < 0.001) to 109,~-transformed monthly instantaneous growth rate (G30) with chlorophyll b being the more important variable. Inclusion of monthly initial shell height in the regression analysis increased to 0.62 and 0.44 for Year 0 and Year 1 equations (p <0.001), respectively. Correlation of chlorophyll b to G.30 may b e indicative of the role of small nanoplankton in oyster diets. Monthly oyster growth rates were primarily regulated by food supply with temperature a secondary factor. Growth rates were highly site-specific depending on food supply and salinity conditions.

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The growth of oysters Ostrea edulis and Crassostrea gigas in Emsworth Harbour

Cited by 32 publications

References 8 publications

Bivalve-enhanced nitrogen removal from coastal estuaries

Bivalve-enhanced nitrogen removal from coastal estuaries

Mortality, growth and somatic secondary production of the bivalve, Pinna rugosa (sowerby), in suspended and bottom culture in Bahia de La Paz, Mexico

Multivariate analyses of the role of environmental factors in seasonal and site-related growth variation in the Pacific oyster Crassostrea gigas

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