995 resultados para United States. Immigration and Naturalization Service.


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This paper summarizes current information on the American shad, Alosa sapidissima, and describes the species and its fishery. Emphasis is placed on (1) life history of the fish, (2) condition of the fishery by State and water areas in 1960 compared to 1896 when the last comprehensive description was made, (3) factors responsible for decline in abundance, and (4) management measures. The shad fishery has changed little over the past three-quarters of a century, except in magnitude of yield. Types of shad-fishing gear have remained relatively unchanged, but many improvements have been made in fishing techniques, mostly to achieve economy. In 1896 the estimated catch was more than 50 million pounds. New Jersey ranked first in production with about 14 million pounds, and Virginia second with 11 million pounds. In 1960 the estimated catch was slightly more than 8 million pounds. Maryland ranked first in production with slightly more than 1.5 million pounds, Virginia second with slightly less than 1.4 million pounds, and North Carolina third with about 1.3 million pounds. Biological and economic factors blamed for the decline in shad abundance, such as physical changes in the environment, construction of dams, pollution, over-fishing, and natural cycles of abundance, are discussed. Also discussed are methods used for the rehabilitation and management of the fishery, such as artificial propagation, installation of fish-passage facilities at impoundments, and fishing regulations. With our present knowledge, we can manage individual shad populations; but, we probably cannot restore the shad to its former peak of abundance.

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Cover title.

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The age and growth dynamics of the spinner shark (Carcharhinus brevipinna) in the northwest Atlantic Ocean off the southeast United States and in the Gulf of Mexico were examined and four growth models were used to examine variation in the ability to fit size-at-age data. The von Bertalanffy growth model, an alternative equation of the von Bertalanffy growth model with a size-at-birth intercept, the Gompertz growth model, and a logistic model were fitted to sex-specific observed size-at-age data. Considering the statistical criteria (e.g., lowest mean square error [MSE], high coefficient-of-determination, and greatest level of significance) we desired for this study, the logistic model provided the best overall fit to the size-at-age data, whereas the von Bertalanffy growth model gave the worst. For “biological validity,” the von Bertalanffy model for female sharks provided estimates similar to those reported in other studies. However, the von Bertalanffy model was deemed inappropriate for describing the growth of male spinner sharks because estimates of theoretical maximum size (L∞) indicated a size much larger than that observed in the field. However, the growth coefficient (k= 0.14/yr) from the Gompertz model provided an estimate most similar to that reported for other large coastal species. The analysis of growth for spinner shark in the present study demonstrates the importance of fitting alternative models when standard models fit the data poorly or when growth estimates do not appear to be realistic.

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For more than 25 years all sea turtle products have been prohibited from international commerce by the 170-member nations of the Convention on International Trade in Endangered Species (CITES). Sea turtles continue to be threatened by direct take (including poaching) and illegal trade despite multi-national protection efforts. Although take may contribute significantly to sea turtle decline, illegal take is difficult to measure since there are few quantified records associated with legal fisheries and fewer still for illegal take (poaching). We can, however, quantify one portion of the illegal sea turtle trade by determining how many illegal products were seized at United States ports of entry over a recent 10-year period. The United States Fish and Wildlife Service (USFWS) oversees the import and export of wildlife and wildlife products, ensuring that wildlife trade complies with United States laws and international treaties. Additionally, the USFWS has legal authority to target suspected illegal wildlife activity through undercover and field investigations. In an effort to assess the scale of illegal sea turtle take and trade, we have conducted a 10-year (1994 – 2003) review of the law enforcement database maintained by the USFWS. This database tracks the number and type of wildlife cases, the quantity of seized products, and the penalties assessed against violators. These data are minimum estimates of the sea turtle products passing through the United States borders, as smuggled wildlife is oftentimes not detected.

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EXTRACT (SEE PDF FOR FULL ABSTRACT): We have analyzed streamflow variations recorded at 15 USGS gauging stations in California during the past 90 years or so. The anomalies (departures from the 1960-1990 mean discharge) of streamflow on annual-to-decadal time scales are strongly correlated with precipitation anomalies in each drainage basin. ... Although causes of the decadal climate (precipitation) variability are not known with certainty, the use of streamflow records may help us understand the relative strengths of moisture sources and shift of the jet stream in atmospheric circulation.

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Conventional wisdom on party systems in advanced industrial democracies holds that modern electorates are dealigned and that social cleavages no longer structure party politics. Recent work on class cleavages has challenged this stylized fact. The analysis performed here extends this criticism to the religious-secular cleavage. Using path analysis and comparing the current electorates of the United States, Germany, and Great Britain with the early 1960s, this paper demonstrates that the religious-secular cleavage remains or has become a significant predictor of conservative vote choice. While the effects of the religious-secular cleavage on vote choice have become largely indirect, the total of the direct and indirect effects is substantial and equivalent to the effects of class and status.

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The Falkland Islands War of 1982 was fought over competing claims to sovereignty over a group of islands off the east coast of South America. The dispute was between Argentina and the United Kingdom. Argentina claims the islands under rights to Spanish succession, the fact that they lie off the Argentine coast line and that in 1833 Great Britain took the islands illegally and by force. The United Kingdom claims the islands primarily through prescription--the fact that they have governed the islands in a peaceful, continuous and public manner since 1833. The British also hold that the population living on the islands, roughly eighteen hundred British descendants, should be able to decide their own future. The United Kingdom also lays claim to the islands through rights of discovery and settlement, although this claim has always been challenged by Spain who until 1811 governed the islands. Both claims have legal support, and the final decision if there will ever be one is difficult to predict. Sadly today the ultimate test of sovereignty does not come through international law but remains in the idea that "He is sovereign who can defend his sovereignty." The years preceding the Argentine invasion of 1982 witnessed many diplomatic exchanges between The United Kingdom and Argentina over the future of the islands. During this time the British sent signals to Argentina that ii implied a decline in British resolve to hold the islands and demonstrated that military action did more to further the talks along than did actual negotiations. The Argentine military junta read these signals and decided that they could take the islands in a quick military invasion and that the United Kingdom would consider the act as a fait accompli and would not protest the invasion. The British in response to this claimed that they never signaled to Argentina that a military solution was acceptable to them and launched a Royal Navy task force to liberate the islands. Both governments responded to an international crisis with means that were designed both to resolve the international crisis and increase the domestic popularity of the government. British Prime Minister Margaret Thatcher was facing an all-time low in popularity for post-War Prime Ministers while Argentine President General Galtieri needed to gain mass popular support so he could remain a viable President after he was scheduled to lose command of the army and a seat on the military junta that ran the country. The military war for the Falklands is indicative of the nature of modern warfare between Third World countries. It shows that the gap in military capabilities between Third and First World countries is narrowing significantly. Modern warfare between a First and Third World country is no longer a 'walk over' for the First World country.