14 resultados para Creative process. Dance. History. Body. Work in Progress

em Aquatic Commons


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This paper provides an historical review of homarid lobster fisheries, the development and usage of lobster hatcheries, and much of the research influenced by hatchery-initiated studies on natural history, physiology, and morphological development of the lobster, Homarus spp. Few commercial lobster hatcheries exist in the world today, yet their potential usage in restocking efforts in various countries is constantly being reexamined, particularly when natural stocks are considered “overfished.” Furthermore, many individual researchers working on homarid lobsters use smallscale hatchery operations to provide the animals necessary for their work as well as animals reared and provided by various governmental agencies interested in specific projects on larvae, postlarvae, or juveniles. Such researchers can benefi t from the information in this review and can avoid many pitfalls previously documented. The development of hatcheries and the experimental studies that were generated from their activities have had a direct impact on much of the research on lobsters. The past work arising from hatchery operations—descriptions of life stages, behavior, physiology, etc.—has generally been confirmed rather than refuted and has stimulated further research important for an understanding of the life history of homarid lobsters. The connections between homarid fisheries and hatchery operations (i.e. culturing of the lobsters), whether small- or large-scale for field and laboratory research, are important to understand so that better tools for fishery management can be developed. This review tries to provide such connections. However, the rearing techniques in use in today’s hatcheries—most of which are relics from the past—are clearly not effi cient enough for large-scale commercial aquaculture of lobsters or even for current restocking efforts practiced by several countries today. If hatcheries are to be used to supplement homarid stocks, to restock areas that were overfished, or to reintroduce species into their historical ranges, there is a clear need to further develop culture techniques. This review should help in assessments of culturing techniques for Homarus spp. and provide a reference source for researchers or governmental agencies wishing to avoid repeating previous mistakes.

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This guidebook attempts to provide a quick overview of the Work in Fishing Convention, 2007, which was adopted in Geneva, Switzerland, in June 2007 at the 96th International Labour Conference (ILC) of the International Labour Organization (ILO). It does not purport to provide interpretation of any provisions of the Convention and should not in any way be treated as a substitute for the actual provisions it contains. This guidebook is intended mainly to help those unfamiliar with the Convention and the working of the ILO and the ILC, gain some understanding of the relevant issues. In particular, it is hoped that the guidebook will aid fish workers and their organizations understand the possible benefits and implications of the Convention for artisanal and small-scale fisheries in developing countries.

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Presentation to elected officials [and American Fisheries Society] on the wealth of research to be done in the Chesapeake Bay. Citing drop in oyster production from a high of 17,000,000 bushels in 1885 to 2,000,000 bushels in 1925 or one-eighth of its one-time abundance. Citing water studies through the late 1880's-90's. Report of experiments with the Japanese Oyster O. gigas. Also addresses Crab, Callinectes sapidus and classes held. (PDF contains 7 pages)

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This study aims to reconstruct the history of shore whaling in the southeastern United States, emphasizing statistics on the catch of right whales, Eubalaena glacialis, the preferred targets. The earliest record of whaling in North Carolina is of a proposed voyage from New York in 1667. Early settlers on the Outer Banks utilized whale strandings by trying out the blubber of carcasses that came ashore, and some whale oil was exported from the 1660s onward. New England whalemen whaled along the North Carolina coast during the 1720s, and possibly earlier. As some of the whalemen from the northern colonies moved to Nortb Carolina, a shore-based whale fishery developed. This activity apparently continued without interruption until the War of Independence in 1776, and continued or was reestablished after the war. The methods and techniques of the North Carolina shore whalers changed slowly: as late as the 1890s they used a drogue at the end of the harpoon line and refrained from staying fast to the harpooned whale, they seldom employed harpoon guns, and then only during the waning years of the fishery. The whaling season extended from late December to May, most successfully between February and May. Whalers believed they were intercepting whales migrating north along the coast. Although some whaling occurred as far north as Cape Hatteras, it centered on the outer coasts of Core, Shackleford, and Bogue banks, particularly near Cape Lookout. The capture of whales other than right whales was a rare event. The number of boat crews probably remained fairly stable during much of the 19th century, with some increase in effort in the late 1870s and early 1880s when numbers of boat crews reached 12 to 18. Then by the late 1880s and 1890s only about 6 crews were active. North Carolina whaling had become desultory by the early 1900s, and ended completely in 1917. Judging by export and tax records, some ocean-going vessels made good catches off this coast in about 1715-30, including an estimated 13 whales in 1719, 15 in one year during the early 1720s, 5-6 in a three-year period of the mid to late 1720s, 8 by one ship's crew in 1727, 17 by one group of whalers in 1728-29, and 8-9 by two boats working from Ocracoke prior to 1730. It is impossible to know how representative these fragmentary records are for the period as a whole. The Carolina coast declined in importance as a cruising ground for pelagic whalers by the 1740s or 1750s. Thereafter, shore whaling probably accounted for most of the (poorly documented) catch. Lifetime catches by individual whalemen on Shackleford Banks suggest that the average annual catch was at least one to two whales during 1830·80, perhaps about four during the late 1870s and early 1880s, and declining to about one by the late 1880s. Data are insufficient to estimate the hunting loss rate in the Outer Banks whale fishery. North Carolina is the only state south of New Jersey known to have had a long and well established shore whaling industry. Some whaling took place in Chesapeake Bay and along the coast of Virginia during the late 17th and early 18th centuries, but it is poorly documented. Most of the rigbt whales taken off South Carolina, Georgia, and northern Florida during the 19th century were killed by pelagic whalers. Florida is the only southeastern state with evidence of an aboriginal (pre-contact) whale fishery. Right whale calves may have been among the aboriginal whalers' principal targets. (PDF file contains 34 pages.)

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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.

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This is the history of contamination in sediments from the Mersey Estuary: Development of a chronology for the contamination of the Mersey Estuary by heavy metals and organochlorines Report produced by the Environment Agency in 1998. This report looks at the history of industrial contamination of the Mersey and Ribble Estuaries back to the early part of the last century, many decades before the start of monitoring programmes providing a remarkably detailed picture of very complex changes. There is a clear record in the sediment of the contamination by each heavy metal (including: Cu, Cr, Hg, Pb, Zn) and organochlorine chemical (including DDT isomers and PCB congeners) studied. The results of the study clearly show the increases in levels of contamination as industry expanded early last century followed by various improvements as this century progressed. Each pollutant has its own idiosyncratic pattern of change with some improvements predating modern environmental concerns whilst other changes seem to relate directly to recent improvements in legislative control. Overall, for the pollutants studied, the results clearly demonstrate the magnitude of improvement that has been achieved in what was a very polluted area. The only major reservation to this story is that despite the wide range of substances covered, many other potentially important pollutants remain to be studied in a similar manner.

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EXTRACT (SEE PDF FOR FULL ABSTRACT): The history of the El Nino phenomena is recorded in both the fluvial and coastal sediments of northern Peru. The fluvial record was presented at the 1987 PACLIM Workshop and is discussed in detail elsewhere (Wells, 1987). However, the number of radiocarbon dated El Nino events has increased since Wells (1987) was published; this data is presented in Table 1.

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The effect of AC and DC electric stimulations on the heart-rate and the entire body of Heteropneustis fossillis, Tilapia mossambica and Macrobrachium rosenbergii were studied and presented in kymograph tracings. The reaction of spinal cord in Puntius ticto, Heteropneustis fossilis and Tilapia mossambica to D. C. field was observed to find out its role in electric shocks. A test-check of the electrical resistance of a few species was also conducted. The effect of D. C. and A.C. on the body muscle was found to be the same as that in the case of frog. Different degrees of cardiac slowing were observed in AC and DC. Unbalanced galvanotropic movements were also noticed in spinal fishes.

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