21 resultados para 980 History of South America

em Aquatic Commons


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The paper presents: 1) biologic summaries for each of the formations for which paleontologic data are available, with brief discussions of the geologic age; 2) geologic correlations of the formations and the distribution of their age-equivalents in Central America, the West Indies, and the southeastern United States; 3) an outline of the paleogeography of middle America. The biologic summaries are based on the paleontologic memoirs in this vol. by Messars. Howe, Berry, Chuchman, Jackson, Canu and Bassler and Pilsbry, Miss Rathbun and myself.

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Snoek (Thyrsites atun) is a valuable commercial species and an important predator of small pelagic fishes in the Benguela ecosystem. The South African population attains 50% sexual maturity at a fork length of ca.73.0 cm (3 years). Spawning occurs offshore during winter−spring, along the shelf break (150–400 m) of the western Agulhas Bank and the South African west coast. Prevailing currents transport eggs and larvae to a primary nursery ground north of Cape Columbine and to a secondary nursery area to the east of Danger Point; both shallower than 150 m. Juveniles remain on the nursery grounds until maturity, growing to between 33 and 44 cm in the first year (3.25 cm/month). Onshore– offshore distribution (between 5- and 150-m isobaths) of juveniles is deter-mined largely by prey availability and includes a seasonal inshore migration in autumn in response to clupeoid recruitment. Adults are found through-out the distribution range of the species, and although they move offshore to spawn—there is some southward dispersion as the spawning season progresses—longshore movement is apparently random and without a seasonal basis. Relative condition of both sexes declined dramatically with the onset of spawning. Mesenteric fat loss was, however, higher in females, despite a greater rate of prey consumption. Spatial differences in sex ratios and indices of prey consumption suggest that females on the west coast move inshore to feed between spawning events, but that those found farther south along the western Agulhas Bank remain on the spawning ground throughout the spawning season. This regional difference in female behavior is attributed to higher offshore abundance of clupeid prey on the western Agulhas Bank, as determined from both diet and rates of prey consumption.

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Espanol: En la presente lista bibliográfica fueron recopiladas las referencias sobre los peces continentales de la Argentina, del período comprendido entre mediados del siglo XVIII y fines del año 2005. Incluye las listas bibliográficas publicadas durante los años 1981 a 2004, y las citas no mencionadas en ellas. Se incluyeron el ISSN o ISBN según correspondiera, la abreviatura oficial y el lugar de origen de las publicaciones. En algunos casos, los ISSN, las abreviaturas de los nombres de las publicaciones o su procedencia, mencionados en los catálogos, no coinciden con los de la home page de la publicación. Una bibliografía puede ser muy rica y aún estar incompleta. Requiere de sus lectores algún interés histórico, y aún un interés profundo por su tema. Ante una bibliografía, muchos investigadores preferirían no encontrar algunas referencias, y de hecho, muchas son oportunamente olvidadas. Por no saber como hacerlo, o por menosprecio, estas listas raramente son citadas en los trabajos, aunque sobre algunos temas en particular, sería realmente difícil formarse una idea si las bibliografías no existieran. Aún desde el comienzo es complicado precisar un criterio de inclusiones. Por ejemplo, gran parte de la ictiofauna Argentina se encuentra también en Brasil. ¿Justifica esto incluir informes perdidos sobre artes de pesca en una cuenca distante? ¿Deben los clásicos, que todo el mundo conoce y el que se inicia encontrará sin dificultad, ser incluidos? Aún a un grupo que se dedicara full time a este trabajo, le sería difícil verificar la precisión de las citas antiguas, en las que fechas y autoría cambian según la investigación histórica. En una bibliografía más o menos general, la perfección atenta contra la publicación. Sin embargo, pensamos que es conveniente hacerlas. Una mirada a este volumen, muestra la enorme cantidad de desarrollos en muchos temas, y la regla que uno de nosotros ha mencionado desde hace tiempo: siempre hay más publicado sobre un tema de lo que uno cree. La sospecha de que con sólo mirar lo que está hecho, muchos subsidios podrían utilizarse para algo más útil que algunas evaluaciones repetidas de recursos o biodiversidad, es un poco pesimista y no haremos perder trabajos insistiendo en eso. Cada generación elige sus metas, su propia base epistemológica, sus trabajos preferidos y los que desecha. Aún en trabajos perdidos o de mala calidad, es posible encontrar datos valiosos. Ningún proyecto, por mejor diseñado que esté, podrá mostrar en el presente los organismos que vivían en el pasado en un lugar en el que las condiciones han cambiado, o lo hará en términos de otra disciplina. En los temas aplicados la información del pasado puede ser importantísima. Aún en una disciplina tan conservadora como la nomenclatura, los cambios pueden ser exasperantes; no pueden serlo menos en las que intrínsecamente, como la ecología, es lo que estudian. Para dar una idea más precisa del desarrollo de la ictiología en la Argentina, esta lista podría ir acompañada de una apreciación crítica. Entendemos que una tarea así exige un trabajo diferente, de cierta magnitud y con no pocos elementos históricos. Aunque tiene deficiencias, la ictiología argentina constituye una acumulación de conocimientos de considerable calidad y pertinencia para la historia natural de América del Sur. Dejamos a los lectores que cada uno haga la suya. English: For the present list, references on freshwater fishes of Argentina were compiled from the period between middle XVIII Century and the end of the year 2005. It includes previous lists published during 1981 to 2004, and references not mentioned therein. The ISSN o ISBN numbers were included, as well as the official abbreviations and the place of origin of the periodicals. In some cases, these data as quoted in catalogs, do not agree with those in the home page of the publication. A bibliography may be very rich and anyway never complete. It requires from its readers some historic interest and indeed a deep interest on his (her) subject. Browsing a bibliography, many researchers would prefer not to find some references, and in fact, sometimes they forget some of them. Not imagining how to do it, or because people do not concede importance to them, bibliographic lists are rarely quoted in papers, though some subjects would be rather difficult to understand if list of publications would not exist. Even from the beginning, it is difficult to precise a criterion of inclusions. For example, many Argentine fishes occur also in Brazil. Does this justify the inclusion of grey reports on a distant basin? Should classic works, that everybody knows and are easily found, be included? Is near impossible, even for a group dedicated full time to this work, to verify the precision of old citations, whose dates and authorship change according to authorities and historical research. In a more or less general bibliography, completeness is against publication. Nevertheless, we think that is convenient to prepare these lists. A look at this volume shows the enormous developments in many subjects, and the rule that one of us mentioned long ago: there are always more papers on any subject than one suspects. Looking at what has already been done raises the suspicion that many grants could be used for something more useful than repeated evaluations of biodiversity or resources. This is a bit pessimistic, and we do not want to erase working opportunities. Each generation chooses its targets, its own epistemological base, its preferred papers and those that rejects. Even in lost or bad quality papers, the possibility of finding valuable information exists. No project, whatever the appropriateness of its design, could show at present which organisms lived in the past in a place where environmental conditions have changed, or it will do it in terms of another discipline. In applied subjects, information from the past can be very important. Even in a conservative discipline as nomenclature, changes can be exasperating. They are not lesser in those like ecology, where change itself is studied. To provide a more precise idea of the development of ichthyology in Argentina, this list could be accompanied by a critical appreciation. We understood that such an aim requires a different work, with no few historical elements and of certain magnitude. In spite of some deficiencies, Argentine ichthyology, resulting from collaboration of both local and foreign people, constitutes a bulk of knowledge of considerable quality and pertinence for the natural history of South America. We leave each reader to make his (or her) own evaluation. (Texto en Espanol. PDF tiene cien setenta paginas.)

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Unlike Africa and Asia, where a large part of the population are heavily dependent upon fishing for their livelihoods, fishing for a living in the interior of Central and South America (CSA) remains a marginal occupation for all but the most isolated of families. As such, the economics and management of fisheries on the continent have received little attention from within the continent and the rest of the world. This study shows that while a number of studies have been carried out on fishing in the region, they tend to be limited in their geographical focus and time scale. Although fishing of freshwater species may appear to be comparatively insignificant in the region, the rivers of CSA are very important. This report attempts to analyze the literature available on CSA river fisheries and attempts to draw out an economic value of these fisheries. It is divided into a number of sections. First, the authors describe the major river basins on the continent, characterize their fisheries, and place freshwater fisheries in CSA into a global context. Second, the authors provide a review of valuation techniques for fisheries and use this analytical framework to review the principal literature on freshwater fisheries in the region. Then they turn their attention to the economic impact of dams and water abstraction schemes, reviewing the available literature to ascertain how/if economic values are computed for the impact on fisheries. Finally, they offer some conclusions and recommendations on the direction for future studies of freshwater fisheries in CSA.

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Water bodies located at 34º 58' S, 62º 58' W formed after 1980 by 30 % increasing rainfall during the last half century, were colonized by ten fish species which are a subset of the commonest species living in the pampasic lagunas. These new populations imply a displacement of the West of Pampasian fishes to areas of the western basins previously lacking fish.

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This is a broad historical overview of the bay scallop, Argopecten irradians, fishery on the East and Gulf Coasts of North America (Fig. 1). For a little over a century, from about the mid 1870’s to the mid 1980’s, bay scallops supported large commercial fisheries mainly in the U.S. states of Massachusetts, New York, and North Carolina and on smaller scales in the states in between and in western Florida. In these states, the annual harvests and dollar value of bay scallops were far smaller than those of the other important commercial mollusks, the eastern oysters, Crassostrea virginica, and northern quahogs, Mercenaria mercenaria, but they were higher than those of softshell clams, Mya arenaria (Table 1). The fishery had considerable economic importance in the states’ coastal towns, because bay scallops are a high-value product and the fishery was active during the winter months when the economies in most towns were otherwise slow. The scallops also had cultural importance as a special food, an ornament owing to its pretty shell design, and an interesting biological component of

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Dehram group includes Faraghan, Dalan and Kangan formations. Kangan formation ages lower terias. That is one of the important reservoir rocks of southern Iran and Persian Gulf. In this research Kangan formation is studied in two A and B wells. Based on 75 studies on thin section, four carbonate litho acies association A, B, C, D with 12 subfacies are identified. A lithofacies association includes 4 subfacies: A1, A2, A3 and A4. B lithofacies association consists of 3 subfacies: B1, B2 and B3. C lithofacies association consists of 3 subfacies: C1, C2, C3 and D lithofacies association includes 2 subfacies: D1 and D2. On the base of studies lithofacies association of Kangan formations are formed in 3 environments of: Tidal Flat, Lagoon and Barrier Shore Complex in a Carbonated Platform Ramp type. Diagenetic processes have effected this formation. The most important Diagenetic processes are: Cementation, Anhydritization, Micrization, Neomorphism, Bioturbation, Dissolution, Compaction, Dolomitization and Porosity. Sequence staratigraphy studies were performed base on the vertical and horizontal relationship of lithofacies association and well logging in gamma ray and sonic type that causes the identification of two sedimentary sequences: First sedimentary sequence includes: Transgressive System Tract (TST) and High Stand System Tract (HST). The lower boundary of this sequence is in Sequence Boundary 1 (SB1) which shows unconformities of Dalan and Kangan that are Permian-terias unconformities. The upper boundary is in Sequence Boundary 2 (SB2) type that is identified by carbonate facies associated by anhydrite nodular. Second sedimentary sequence includes: TST and HST. Lower and upper boundaries of these sequences are both in SB2 type. The lower and upper boundary is made of carbonate facies with anhydrite nodular.

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With the cooperation of several of the executive departments, and of the Field Museum of Natural History, a party of about 10 naturalists was accordingly sent to the zone, and the results so far accomplished have been very satisfactory. Large collections of biological material have been received, including specimens of a considerable number of genera and species new to science. It also seemed important to determine exactly the geographical distribution of the various organisms inhabiting the Isthmus, which is one of the routes by which the animals and plants of South America have entered North America and vice versa. The estimated cost of the survey which would have to be met by the Institution is $11,000...

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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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Covers the history of the study of boring sponges, taxonomy and distributions. Also includes identification of species, descriptions, key, references and plates. (PDF contains 30 pages)

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We examined the incidental catches of American shad (Alosa sapidissima) taken during research cruises and in commercial and recreational landings along the Pacific coast of North America during over 30 years of sampling. Shad, an introduced species, was mainly found over the shallow continental shelf, and largest catches and highest frequency of occurrences were found north of central Oregon, along the coasts of Washington and Vancouver Island, and in California around San Francisco Bay. Migrations to the north off Washington and Vancouver were seen during spring to fall, but we found no evidence for large-scale seasonal migrations to the south during the fall or winter. The average weight of shad increased in deeper water. Sizes were also larger in early years of the study. Most were caught over a wide range of sea surface temperatures (11–17°C) and bottom temperatures (6.4–8.0°C). Abundance of shad on the continental shelf north of 44°N was highly correlated with counts of shad at Bonneville Dam on the Columbia River in the same year. Counts were negatively related to average weights and also negatively correlated with the survival of hatchery coho salmon (Oncorhynchus kisutch), indicating that survival of shad is favored by warm ocean conditions. Examining the catch during research cruises and commercial and recreational landings, we concluded that American shad along the Pacific coast have adapted to the prevailing environmental conditions and undertake only moderate seasonal migrations compared with the long seasonal migrations of shad along the Atlantic coast of North America. We suggest that the large spawning populations in the Columbia River and San Francisco Bay areas explain most of the distributional features along the Pacific coast.

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Feeding habits and feeding strategy of red rockfish (Sebastes capensis) were studied from fish captured along most of the range of this species in coastal waters of South America. Stomach contents of 613 individuals, collected during 2003, were analyzed. Fish were obtained from six locations along the Chilean (23°S to 46°S) and Argentinian (43°S) coasts. The main prey items were Mysidacea (75.06% IRI), Osteichthyes (6.29% IRI),and Rhynchocinetes typus (6.03% IRI). Predator sex and size did not significantly affect the diet, but significant differences were found between locations. Four geographical areas, discriminated by prey occurrence and frequencies, were determined: three on the Pacific coast and one on the Atlantic coast. These areas correspond roughly with biogeographic zones described for the Chilean and southern Argentinian coasts. The feeding strategy index (FSI) indicated a specialized feeding strategy for S. capensis for most of its range. However, the FSI does not include the behaviour of a predator, and the FSI must be interpreted carefully for fishes like S. capensis that are passive ambush feeders. The abundance and availability of different prey may explain both the geographic differences in dietary composition and the specialized feeding strategy of S. capensis.

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Aboriginal Australians consumed oysters before settlement by Europeans as shown by the large number of kitchen middens along Australia's coast. Flat oysters, Ostrea angasi, were consumed in southeastern Australia, whereas both flat and Sydney rock oysters, Saccostrea glomerata, are found in kitchen middens in southern New South Wales (NSW), but only Sydney rock oysters are found in northern NSW and southern Queensland. Oyster fisheries began with the exploitation of dredge beds, for the use of oyster shell for lime production and oyster meat for consumption. These natural oyster beds were nealy all exhausted by the late 1800's, and they have not recovered. Oyster farming, one of the oldest aquaculture industries in Australia, began as the oyster fisheries declined in the late 1800's. Early attempts at farming flat oysters in Tasmania, Victoria, and South Australia, which started in the 1880's, were abandoned in the 1890's. However, a thriving Sydney rock oyster industry developed from primitive beginnings in NSW in the 1870's. Sydney rock oysters are farmed in NSW, southern Queensland, and at Albany, Western Australia (WA). Pacific oysters, Crassostrea gigas, are produced in Tasmania, South Australia, and Port Stephens, NSW. FLant oysters currently are farmed only in NSW, and there is also some small-scale harvesting of tropical species, the coarl rock or milky oyster, S. cucullata, and th black-lip oyster, Striostrea mytiloides, in northern Queensland. Despite intra- and interstate rivalries, oyster farmers are gradually realizing that they are all part of one industry, and this is reflected by the establishment of the national Australian Shellfish Quality Assuarance Program and the transfer of farming technology between states. Australia's oyster harvests have remained relatively stable since Sydney rock oyster production peaked in the mid 1970's at 13 million dozen. By the end of the 1990's this had stabilized at around 8 million dozen, and Pacific oyster production reached a total of 6.5 million dozen from Tasmania, South Australia, and Port Stephens, a total of 14.5 million dozen oysters for the whole country. This small increase in production during a time of substantial human population growth shows a smaller per capita consumption and a declining use of oysters as a "side-dish."