Journal of Shellfish Research articles from August 2006

Journal of Shellfish Research archives from August 2006

Reproductive patterns and their influence on the population genetics of sympatric species of the genus Crepidula (Gastropoda: Calyptraeidae).
August 1, 2006... ABSTRACT Crepidula dilatata (Lamark, 1822) and Crepidula fecunda (Gallardo, 1979) are sympatric species in southern Chile. Separating them by species is difficult because they are morphologically similar; an important character, which separates...

Local distribution and temperature preferences of predatory whelks (Thais spp.) in Taiwan: implications for oyster culture.
August 1, 2006... ABSTRACT Among the Thais species, the broad consensus has long been that Thais clavigera (Kuster) is the most noxious predator of cultured oysters in Taiwan. Recently, two new Thais species (i.e., T. rufotincta Tan & Sigurdsson 1996 and T....

Energy budget of cultured female abalone Haliotis tuberculata (L.).
August 1, 2006... ABSTRACT This study evaluates the effects of three diets, at 3 different temperatures (15[degrees], 18[degrees] and 22[degrees]C), on the energy budget of one-year-old abalone. The organisms were fed either an experimental diet based on...

The hypobranchial gland from the purple snail Plicopurpura pansa (Gould, 1853) (prosobranchia: Muricidae).
August 1, 2006... ABSTRACT Results are presented on the histology of the hypobranchial gland of the marine muricid Plicopurpura pansa (Gould 1853). The general structure and secretory features were investigated using light microscopy and histochemical methods...

Can the collection of "Tyrian purple" from Plicopurpura pansa (Gould, 1853) (Prosobranchia, Muricidae) be blamed for its declining population?
August 1, 2006... ABSTRACT Marked, sized and sex determined purple snails Plicopurpura pansa, (Gould, 1853) were distributed randomly among other snails in crevices of an intertidal rocky island splashed during high tides by high impact waves. After 89 days 18%,...

Ultrastructure of spermatogenesis in the white clam Chione californiensis (Broderip, 1835) (Mollusca: Pelecypoda).
August 1, 2006... ABSTRACT Although studies of this species have focused on its reproductive cycle, there is no literature available on the ultrastructure of its germ cells. This study consequently aims to describe the latter cells as well as the shape of the...

Out-crossing among commercial strains of the northern quahog, Mercenaria mercenaria: survival, growth and implications for selective breeding.
August 1, 2006... ABSTRACT Because the accumulation of inbreeding within hatchery-propagated stocks of the hard clam, Mercenaria mercenaria (Linnaeus, 1758), could result in reduced growth and survival, we studied the potential for improving performance through...

A population dynamics model of the hard clam, Mercenaria mercenaria: development of the age- and length-frequency structure of the population.
August 1, 2006... ABSTRACT An individual-based model was developed to simulate growth of the hard clam, Mercenaria mercenaria, in response to temperature, salinity and food supply conditions. Unique characteristics of the model are that: (1) length and tissue...

Recruitment patterns and precautionary exploitation rates for Geoduck (Panopea abrupta) populations in British Columbia.
August 1, 2006... ABSTRACT An age-structured projection model was used to study the impacts of alternative exploitation intensities on geoduck populations, based on a large accumulation of survey data, age composition data and published estimates of natural...

Differences of Turkish clam (Ruditapes decussates) and Manila clam (Ruditapes philippinarum) according to their proximate composition and heavy metal contents.
August 1, 2006... ABSTRACT The aim of this study is to determine the proximate composition, biometrical measurements and heavy metal content differences of marine bivalve Ruditapes philippinarum (Venice, Italy) and Ruditapes philippinarum (Izmir, Turkey. No...

Biotic and abiotic factors influencing growth and survival of wild and cultured individuals of the softshell clam (Mya arenaria L.) in Eastern Maine.
August 1, 2006... ABSTRACT A series of intertidal field experiments was conducted from 1986-2003 in eastern Maine to examine biotic and abiotic factors influencing the growth and survival of wild and cultured individuals of the softshell clam, Mya arenaria L....

Trends in Maine softshell clam landings.
August 1, 2006... ABSTRACT The soft-shell clam, Mya arenaria (L. 1758), has the highest landed value of Maine bivalves. Landings have been variable over the last century with current landings one third of their historical highs caused by low harvests in Eastern...

Initial recruitment and growth of surfclams (Spisula solidissima Dillwyn) on the inner continental shelf of New Jersey.
August 1, 2006... ABSTRACT Surfclam (Spisula solidissima Dillwyn) larval settlement and the initial growth of recruits were studied on the inner shelf of New Jersey. Initial recruitment was measured by taking weekly benthic core samples during the summer...

Variations in growth and reproduction of bay scallops (Argopecten irradians) (Lamark, 1819) from six subpopulations in the northeastern Gulf of Mexico.
August 1, 2006... ABSTRACT Bay scallops, Argopecten irradians, sustained a valuable commercial and recreational fishery in Florida during the middle part of the last century. In 1994, after decades of declining stocks, state managers closed this fishery to...

Reproduction and spawning in calico scallops, Argopecten gibbus, from Bermuda.
August 1, 2006... ABSTRACT The gametogenic cycle and breeding season of the calico scallop, Argopecten gibbus was examined in Bermuda using quantitative and qualitative methods. Gonadal index varied seasonally, a rapid increase occurring in the winter months...

Assortative fertilization in Chlamys farreri and Patinopecten yessoensis and its implication in scallop hybridization.
August 1, 2006... ABSTRACT Assortative mating and reduced hybrid fitness are typically invoked to explain the stability of hybrid zones and the specification of two closely related taxa. Such examples of mate preferences in nature, especially for broadcast free-...

Genotype-dependent survival, growth, and production in cultured blue mussels, Mytilus SPP.: results of a reciprocal seed transfer experiment.
August 1, 2006... ABSTRACT A reciprocal mussel seed transfer experiment was conducted involving two farm sites (Charles Arm and Thwart island) whose seedstocks differed significantly in their respective compositions of Mytilus edulis L., M. trossulus Gould and...

Genetic management guidelines for captive propagation of freshwater mussels (Unionoidea).
August 1, 2006... ABSTRACT Although the greatest global diversity of freshwater mussels (~300 species) resides in the United States, the superfamily Unionoidea is also the most imperiled taxon of animals in the nation. Thirty-five species are considered extinct,...

Acoustic deterrents do not reduce black drum predation on oysters.
August 1, 2006... ABSTRACT We studied the effectiveness of acoustic deterrents in limiting predation on Louisiana oyster leases by black drum Pogonias cromis. Three acoustic deterrents were used: (1) natural or synthesized alarm sounds; (2) synthesized, low...

Genetic diversity of the European oyster (Ostrea edulis L.) in Nova Scotia: comparison with other parts of Canada, Maine and Europe and implications for broodstock management.
August 1, 2006... ABSTRACT The European oyster (Ostrea edulis) was introduced to the Nova Scotia aquaculture industry 30 years ago using stocks imported from naturalized populations in Maine whose ancestors originated in the Netherlands. This study used 5...

Tissue distribution and hemolymph activity of six enzymes in the American lobster (Homarus americanus): potential markers of tissue injury.
August 1, 2006... ABSTRACT Biochemistry panels are used to help identify tissue injury (e.g., because of inflammation, trauma or hypoxia) in human and veterinary medicine in part, by detecting increased enzyme activity in serum or plasma after release from...

Comparison of early season versus late season trap schedules for harvest of red swamp crawfish Procambarus clarkii cultured in earthen ponds without planted forage.
August 1, 2006... ABSTRACT The effect of a redistribution of the majority of total trap harvest days (69) during April through October on yield of red swamp crawfish Procambarus clarkii cultured in earthen ponds without planted forage was evaluated in northeast...

A perspective on ecological considerations in crawfish pond aquaculture.
August 1, 2006... ABSTRACT The suite of resident, migrant, breeding, and wintering waterbirds depending on this region includes grebes, pelicans, cormorants, anhingas, wading birds, waterfowl, coots, rails, gallinules, shorebirds, gulls, and terns. All taxa now...

Embryo development and morphometry in the blue king crab Paralithodes platypus studied by using image and cluster analysis.
August 1, 2006... ABSTRACT In this paper the embryonic development of laboratory-reared blue king crab, Paralithodes platypus, from the Pribilof Islands in the eastern Bering Sea is described. Developing embryos were removed from a female crab at various...

Timing and seasonality of the terminal molt and mating migration in the spider crab, Maja brachydactyla: evidence of alternative mating strategies.
August 1, 2006... ABSTRACT Timing and synchronization at individual and population levels of the processes related to the terminal molt, gonad maturation, accumulation of energy reserves and migration in the spider crab Maja brachydactyla are analyzed. Also, the...

Effect of different levels of dietary [alpha]-tocopherol on ovarian maturation and reproductive performance of broodstock Litopenaeus vannamei (Boone).
August 1, 2006... ABSTRACT Effects of 4 grade levels of dietary [alpha]-tocopherol (37.82, 115.64, 349.42 and 522.56 mg [kg.sup.-1] diet) on ovarian maturation and reproductive performance of broodstock shrimp, Litopenaeus vannamei were investigated. The...

Inferring shrimp (Pandalus borealis) growth characteristics from life history stage structure analysis.
August 1, 2006... ABSTRACT An aged-based population model was used to simulate shrimp (Pandalus borealis Kroyer) age and stage structures at different growth rates and the results compared with stage structures of populations with known growth rates. Both...

Effects of tidal restrictions and potential benefits of tidal restoration on fecal coliform and shellfish-water quality.
August 1, 2006... ABSTRACT The relationship between artificial tidal restrictions and shellfish-water quality was studied within otherwise sparsely developed estuaries on Cape Cod (Massachusetts, USA). The primary study site, the 600-ha diked Herring River...

TaqMan[R] MCB real-time PCR approach to quantification of Perkinsus marinus and Perkinsus spp. in oysters.
August 1, 2006... ABSTRACT Several molecular diagnostic assays have been developed in an attempt to replace the traditional Ray's Fluid Thioglycollate Medium (RFTM) assay for detection and quantification of Perkinsus marinus in oysters. Real-time PCR technology...

Subspecies characterization of urease-positive thermophilic Campylobacter (UPTC) isolated from shellfish employing modified flagellin (flaA) restriction fragment length polymorphism (RFLP) typing.
August 1, 2006... ABSTRACT Shellfish including oysters (Crassostrea gigas), cockles (Cerastoderma edule) and mussels (Mytilus edulis), have previously been described as an important source of thermophilic campylobacters, with the potential of causing acute...

The effectiveness of heat, cold and 6-dimethylaminopurine shocks for inducing tetraploidy in the Kuruma shrimp, Marsupenaeus japonicus (Bate).
August 1, 2006... ABSTRACT In this study tetraploid Marsupenaeus japonicus (Bate) embryos were produced by preventing the first division in mitosis. The effectiveness of temperature and chemical shocks for producing tetraploid M. japonicus were assessed when...

Preparation of large bivalve specimens for scanning electron microscopy using hexamethyldisilazane (HMDS).
August 1, 2006... ABSTRACT Treatment with hexamethyldisilazane (HMDS) for drying specimens for Scanning Electron Microscopy (SEM) is described for relatively large (>20 mm shell height, SH) individuals of two scallop species, Placopecten magellanicus and...

A new in situ method for measuring seston uptake by suspension-feeding bivalve molluscs.
August 1, 2006... ABSTRACT The most commonly used methods for measuring the amount of seston removed from the water column (uptake) by populations of suspension-feeding bivalve molluscs involve taking discrete water samples followed by laboratory analyses. Here...