History of Oystering in the United States and Canada, Featuring the Eight Greatest Oyster Estuaries

Oyster landings in the United States and Canada have been based mainly on three species, the native eastern oyster, Crassostrea virginica, native Olympia oyster, Ostreola conchaphila, and introduced Pacific oyster, C. gigas. Landings reached their peak of around 27 million bushels/year in the late 1800's and early 1900's when eastern oysters were a common food throughout the east coast and Midwest. Thousands of people were involved in harvesting them with tongs and dredges and in shucking, canning, packing, and transporting them. Since about 1906, when the United States passed some pure food laws, production has declined. The causes have been lack of demand, siltation of beds, removal of cultch for oyster larvae while harvesting oysters, pollution of market beds, and oyster diseases. Production currently is about 5.6 million bushels/year.

Biographic Memoir of Ernest Ingersoll: Naturalist, Shellfish Scientist, and Author

The name Ernest Ingersoll is well-known to many shellfishery biologists as the author of two outstanding monographs on the shellfisheries of the United States and Canada in the 1880's. The first (Ingersoll, 1881a), entitled "A Report on the Oyster-Industry of the United States," was a 252-page description of historical and contemporary oyster fishing' marketing methods, and statistical data in the eastern provinces of Canada and the coastal states of the United States. The second (Ingersoll, 1887), entitled "The Oyster, Scallop, Clam, Mussel, and Abalone Industries," was a l20-page summary of the first monograph about oysters as well as a history and description of contemporary methods and statistical data of the other shellfisheries. Although Ingersoll was, by profession, a naturalist and author but only briefly a shellfish scientist, these monographs are regarded as benchmarks, providing the principal descriptions of shellfisheries in North America in the 1700's and 1800's.

Trace metals in common marine foods of the Pacific Coast

Trace metal analysis of 23 species of common Pacific Coast marine foods revealed high cadmium values for Bent-nosed clams (Macoma nasuta), Bay mussels (Mytilus edulis), Bay oysters (Osrtrea lurida), Pacific oysters (Crassostrea gigas), and Littleneck clams (Protothaca staminea). Metals were found to concentrate in the gills, heart, and visceral mass of all 10 species of bivalve mollusks examined. Swordfish (Xiphias gladius) and Salmon (Oncorhynchus tshawytscha) demonstrated the highest cadmium values for fish flesh.

Effect of Susquehanna River stream flow on Chesapeake Bay salinities and history of past oyster mortalities on upper Bay bars

A study of possible causes for extensive mortality of oysters in the Upper Chesapeake Bay was taken on by year-round monitoring of conditions during a two-year period.

National Centers for Coastal Ocean Science Coastal Ecosystem Assessment Program: a manual of methods

Environmental managers strive to preserve natural resources for future generations but have limited decision-making tools to define ecosystem health. Many programs offer relevant broad-scale, environmental policy information on regional ecosystem health. These programs provide evidence of environmental condition and change, but lack connections between local impacts and direct effects on living resources. To address this need, the National Oceanic and Atmospheric Administration/National Ocean Service (NOAA/NOS) Cooperative Oxford Laboratory (COL), in cooperation with federal, state, and academic partners, implemented an integrated biotic ecosystem assessment on a sub-watershed 14-digit Hydrologic Unit Code (HUD) scale in Chesapeake Bay. The goals of this effort were to 1) establish a suite of bioindicators that are sensitive to ecosystem change, 2) establish the effects of varying land-use patterns on water quality and the subsequent health of living resources, 3) communicate these findings to local decision-makers, and 4) evaluate the success of management decisions in these systems. To establish indicators, three sub-watersheds were chosen based on statistical analysis of land-use patterns to represent a gradient from developed to agricultural. The Magothy (developed), Corsica (agricultural), and Rhode (reference) Rivers were identified. A random stratified design was developed based on depth (2m contour) and river mile. Sampling approaches were coordinated within this structure to allow for robust system comparisons. The sampling approach was hierarchal, with metrics chosen to represent a range from community to cellular level responses across multiple organisms. This approach allowed for the identification of sub-lethal stressors, and assessment of their impact on the organism and subsequently the population. Fish, crabs, clams, oysters, benthic organisms, and bacteria were targeted, as each occupies a separate ecological niche and may respond dissimilarly to environmental stressors. Particular attention was focused on the use of pathobiology as a tool for assessing environmental condition. By integrating the biotic component with water quality, sediment indices, and land- use information, this holistic evaluation of ecosystem health will provide management entities with information needed to inform local decision-making processes and establish benchmarks for future restoration efforts.

Assessing the impacts of the Deepwater Horizon oil spill: the National Status and Trends Program response; a summary report of coastal contamination

NOAA’s National Status and Trends Program (NS&T) collected oyster tissue and sediments for quantification of polycyclic aromatic hydrocarbons (PAHs) and petroleum associated metals before and after the landfall of oil from the Deepwater Horizon incident of 2010. These new pre- and post- landfall measurements were put into a historical context by comparing them to data collected in the region over three decades during Mussel Watch monitoring. Overall, the levels of PAHs in both sediment and oysters both pre- and post-landfall were within the range of historically observed values for the Gulf of Mexico. Some specific sites did have elevated PAH levels. While those locations generally correspond to areas in which oil reached coastal areas, it cannot be conclusively stated that the contamination is due to oiling from the Deepwater Horizon incident at these sites due to the survey nature of these sampling efforts. Instead, our data indicate locations along the coast where intensive investigation of hydrocarbon contamination should be undertaken. Post-spill concentrations of oil-related trace metals (V, Hg, Ni) were generally within historically observed ranges for a given site, however, nickel and vanadium were elevated at some sites including areas in Mississippi Sound and Galveston, Terrebonne, Mobile, Pensacola, and Apalachicola Bays. No oyster tissue metal body burden exceeded any of the United States Food and Drug Administration’s (FDA) shellfish permissible action levels for human consumption.

Scientific assessment of hypoxia in U.S. coastal waters

The occurrence of hypoxia, or low dissolved oxygen, is increasing in coastal waters worldwide and represents a significant threat to the health and economy of our Nation’s coasts and Great Lakes. This trend is exemplified most dramatically off the coast of Louisiana and Texas, where the second largest eutrophication-related hypoxic zone in the world is associated with the nutrient pollutant load discharged by the Mississippi and Atchafalaya Rivers. Aquatic organisms require adequate dissolved oxygen to survive. The term “dead zone” is often used in reference to the absence of life (other than bacteria) from habitats that are devoid of oxygen. The inability to escape low oxygen areas makes immobile species, such as oysters and mussels, particularly vulnerable to hypoxia. These organisms can become stressed and may die due to hypoxia, resulting in significant impacts on marine food webs and the economy. Mobile organisms can flee the affected area when dissolved oxygen becomes too low. Nevertheless, fish kills can result from hypoxia, especially when the concentration of dissolved oxygen drops rapidly. New research is clarifying when hypoxia will cause fish kills as opposed to triggering avoidance behavior by fish. Further, new studies are better illustrating how habitat loss associated with hypoxia avoidance can impose ecological and economic costs, such as reduced growth in commercially harvested species and loss of biodiversity, habitat, and biomass. Transient or “diel-cycling” hypoxia, where conditions cycle from supersaturation of oxygen late in the afternoon to hypoxia or anoxia near dawn, most often occurs in shallow, eutrophic systems (e.g., nursery ground habitats) and may have pervasive impacts on living resources because of both its location and frequency of occurrence.

Histological techniques for marine bivalve molluscs: update

This chapter describes the procedures for determining the reproductive stage of oysters, mytilid mussels, and dreissenid mussels collected for NOAA’s National Status and Trends Mussel Watch Project. Analyses are conducted on paraffin-embedded tissues sectioned at a 5-μm thickness and stained using a pentachrome staining procedure. Each slide is examined microscopically to determine the animal’s sex and stage of gonadal development. A semi-quantitative ranking is assigned.

Conserving oyster reef habitat by switching from dredging and tonging to diver-harvesting

A major cause of the steep declines of American oyster (Crassostrea virginica) fisheries is the loss of oyster habitat through the use of dredges that have mined the reef substrata during a century of intense harvest. Experiments comparing the efficiency and habitat impacts of three alternative gears for harvesting oysters revealed differences among gear types that might be used to help improve the sustainability of commercial oyster fisheries. Hand harvesting by divers produced 25−32% more oysters per unit of time of fishing than traditional dredging and tonging, although the dive operation required two fishermen, rather than one. Per capita returns for dive operations may nonetheless be competitive with returns for other gears even in the short term if one person culling on deck can serve two or three divers. Dredging reduced the height of reef habitat by 34%, significantly more than the 23% reduction caused by tonging, both of which were greater than the 6% reduction induced by diver hand-harvesting. Thus, conservation of the essential habitat and sustainability of the subtidal oyster fishery can be enhanced by switching to diver hand-harvesting. Management schemes must intervene to drive the change in harvest methods because fishermen will face relatively high costs in making the switch and will not necessarily realize the long-term ecological benefits.

Canning of edible oyster

Edible oyster, Crassostrea cucullata, was canned in different filling media viz, its own nector, brine and double refined vegetable oil, to study the effect of each, on the flavour and general quality characteristics of the final product. A method was worked out to produce a canned product, of appealing flavour form oysters after light smoking. The paper reports the results of these studies.

Seasonal variation in the proximate composition of rock oyster Saccostrea cucullata from Bombay coast

Changes in proximate composition of soft tissue of rock oyster Saccostrea cucullata inhabiting a polluted station at Bandra (stn. B) and a relatively clean area at Mudh Island (stn. M) were studied. An average protein content of 48.88 plus or minus 3.73 and 53.68 plus or minus 3.59% were recorded respectively for oysters from stns. M and B and the difference was significant. Mean carbohydrate content in oysters from stn. M amounted to 14.69 plus or minus 3.22 whereas at stn. B it was 8.70 plus or minus 1.61 and the difference was found highly significant. However, appreciable variation between stations was not observed in lipid and carbon content in oysters. Suitable periods for harvesting of these organisms are suggested.

Recent advances and scope for sea farming in India

Although brackishwater prawn and fish culture was traditionally practiced for a long time in the country, efforts at sea farming are still in their infancy. During the past 15 years the Central Marine Fisheries Research Institute has developed various technologies for sea farming of mussels, pearl oysters, production of cultured pearls, edible oysters, clams, prawns, lobsters, seaweeds and more recently sea cucumbers and top shells. The paper outlines recent developments in these areas as well as in others like sea ranching of marine prawns and pearl oyster, and scope for enlarging sea farming activities including development of artificial reefs in India.

Pearl culture and pearl oyster cultivation

Few marine animals have yet been tamed and harnessed for man's use. Of these the bivalves have the greatest potential, and of the bivalves the pearl oysters are perhaps the most thoroughly exploited. Not only are they eaten and their shell put to use, but their nacre secreting properties are tapped to produce pearls by design, rather than by accident as in nature.

The 1958 pearl oyster fishery, Gulf of Mannar

The continental shelf between the three and twelve fathom lines, off the Ceylon coast in the Gulf of Mannar is popularly known as the Pearl Banks. Though the area of this plateau is extensive the pearl oysters are concentrated on restricted areas known as "paars". The more productive of these are the Cheval Group of paars and the Moderagam Paar. The Peria Paar and Twynam's Paar though covering larger areas are not dependable as oyster beds. The True Vankalai, Peria Paar Karai and Muthuvarathu Paars are small in extent, but have yielded oysters on a commercial scale. Although the Ceylon Pearl Banks has been commercially fished for centuries, the first scientific investigation of its pearl oysters on an intensive scale was started by Herdman in 1902 (1902-06) and later continued by Hornell (1905-41), Shipley (1904-06), Pearson (1911-33), Jameson (1912-13), Southwell (1910-14) and Malpas (1922-39).

Copper, zinc, iron and manganese in sediments and in the rock oyster Saccostrea cucullata in Mumbai coast

Sediment and oyster (Saccostrea cucullata) samples were collected at Dhanda, a fishing village in Mumbai, Maharashtra. The samples were analysed for copper, zinc, iron and manganese contents. Metal concentrations in the sediments and bioaccumulated levels in oysters were correlated. There is no positive correlation between the total sedimentary levels of metals analysed and the bioaccumulated levels of respective metals in oyster. A positive correlation between the bioavailable fractions of zinc, iron and manganese, and the bioaccumulated levels exists. Copper, however, shows a negative correlation with respect to the bioaccumulated levels.