228 resultados para French Atlantic


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Species composition, biomass, density, and diversity of benthic invertebrates from six bard-bottom areas were evaluated. Seasonal collections using a dredge, trawl, and suction and grab samplers yielded 432, 525, and 845 taxa, respectively. Based on collections wltb the different gear types, species composition of invertebrates was found to change bathymetrically. Inner- and mlddle-shelf sites were more similar to each other in terms of invertebrate species composition than they were to outer-shelf sites, regardless of season. Sites on the inner and outer shelf were grouped according to latitude; however, results suggest that depth is apparently a more important determinant of invertebrate species composition than either season or latitude. Sponges generally dominated dredge and trawl collections in terms of biomass. Generally, cnidarians, bryozoans, and sponges dominated at sites In terms of number of taxa collected. The most abundant smaller macrofauna collected in suction and grab samples were polychaetes, amphipods, and mollusks. Densities of the numerically dominant species changed botb seasonally and bathymetrically, with very few of these species restricted to a specific bathymetrlc zone. The high diversity of invertebrates from hard-bottom sites is attributed to the large number of rare species. No consistent seasonal changes in diversity or number of species were noted for individual stations or depth zones. In addition, H and its components showed no definite patterns related to depth or latitude. However, more species were collected at middle-shelf sites than at inner- or outer-shelf sites, which may be related to more stable bottom temperature or greater habitat complexity in that area. (PDF file contains 110 pages.)

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Atlantic menhaden, Brrvoortia tyrannus, the object of a major purse-seine fishery along the U.S. east coast, are landed at plants from northern Florida to central Maine. The National Marine Fisheries Service has sampled these landings since 1955 for length, weight, and age. Together with records of landings at each plant, the samples are used to estimate numbers of fish landed at each age. This report analyzes the sampling design in terms of probablity sampling theory. The design is c1assified as two-stage cluster sampling, the first stage consisting of purse-seine sets randomly selected from the population of all sets landed, and the second stage consisting of fish randomly selected from each sampled set. Implicit assumptions of this design are discussed with special attention to current sampling procedures. Methods are developed for estimating mean fish weight, numbers of fish landed, and age composition of the catch, with approximate 95% confidence intervals. Based on specific results from three ports (port Monmouth, N.J., Reedville, Va., and Beaufort, N.C.) for the 1979 fishing season, recommendations are made for improving sampling procedures to comply more exactly with assumptions of the sampling design. These recommendatlons include adopting more formal methods for randomizing set and fish selection, increasing the number of sets sampled, considering the bias introduced by unequal set sizes, and developing methods to optimize the use of funds and personnel. (PDF file contains 22 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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This profile covers life history and environmental requirements of both alewife (Alosa pseudoharengus) and blueback herring (Alosa aestivalis), since their distribution is overlapping and their morphology, ecological role, and environmental requirements are similar. The alewife is an anadromous species found in riverine, estuarine, and Atlantic coastal habitats, depending on life cycle stage, from Newfoundland (Winters et al. 1973) to Soutn Carolina (Berry 1964). Landlocked populations are i n the Great Lakes, Finger Lakes, and many other freshwater lakes (Bigelow and Sch roeder 1953; Scott and Crossman 1973). The blueback herring is an anadromous species found in riverine, estuarine, and Atlantic coastal habitats, depending on life stage cycle, from Nova Scotia to the St. Johns River, Florida (Hildebrand 1963)

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The pressures placed on the natural, environmental, economic, and cultural sectors from continued growth, population shifts, weather and climate, and environmental quality are increasing exponentially in the southeastern U.S. region. Our growing understanding of the relationship of humans with the marine environment is leading us to explore new ecosystem-based approaches to coastal management, marine resources planning, and coastal adaptation that engages multiple state jurisdictions. The urgency of the situation calls for coordinated regional actions by the states, in conjunction with supporting partners and leveraging a diversity of resources, to address critical issues in sustaining our coastal and ocean ecosystems and enhancing the quality of life of our citizens. The South Atlantic Alliance (www.southatlanticalliance.org) was formally established on October 19, 2009 to “implement science-based policies and solutions that enhance and protect the value of coastal and ocean resources of the southeastern United States which support the region's culture and economy now and for future generations.” The Alliance, which includes North Carolina, South Carolina, Georgia, and Florida, will provide a regional mechanism for collaborating, coordinating, and sharing information in support of resource sustainability; improved regional alignment; cooperative planning and leveraging of resources; integrated research, observations, and mapping; increased awareness of the challenges facing the South Atlantic region; and inclusiveness and integration at all levels. Although I am preparing and presenting this overview of the South Atlantic Alliance and its current status, there are a host of representatives from agencies within the four states, universities, NGOs, and ongoing southeastern regional ocean and coastal programs that are contributing significant time, expertise, and energy to the success of the Alliance; information presented herein and to be presented in my oral presentation was generated by the collaborative efforts of these professionals. I also wish to acknowledge the wisdom and foresight of the Governors of the four states in establishing this exciting regional ocean partnership. (PDF contains 4 pages)