857 resultados para species and community
Resumo:
ENGLISH: Yellowfin tuna, Neothunnus macropterus, and skipjack tuna, Katsuwonus pelamis, are fished intensively off the west coast of the Americas in an area from about the California-Mexico border in the north to the Peru-Chile border in the south. The historical development of this fishery, and its expansion by the long-range California fleets of bait and purse-seine vessels, are well documented by Godsil (1938), Scofield (1951) and Shimada and Sehaefer (1956). The quarterly distribution of the tuna catches within this area has been reported for some recent years by Alverson (1959). SPANISH: Los atunes aleta amarilla, Neothunnus macropterus, y barrilete, Katsuwonus pelamis, son pescados con intensidad frente a la costa occidental del continente americano, en un área comprendida más o menos entre la frontera California-México en el norte y el límite Perú-Chile en el sur. El desarrollo histórico de esta pesquería y la expansión que le han dado las flotas californianas de largo radio de acción, formadas por los barcos de carnada y rederos, están bien documentados por Godsil (1938), Scofield (1951) y Shimada y Schaefer (1956). La distribución trimestral de las pescas de atún dentro de esta área ha sido tratada por Alverson (1959) con referencia a años recientes.
Resumo:
Storm force flooding continues to be a major concern in the hurricane season and causes considerable loss to the coastal communities. National Flood Insurance Program (NFIP) provides recovery resources for the flood disaster and dissuades uneconomic uses from locating in flood hazard area. In order to motivate flood insurance purchase and promote increased flood hazard mitigation, the Community Rating System (CRS) that is a part of NFIP, credits 18 community floodplain management activities. However, CRS has been marked by a lack of active participation since its inception limiting its potential effectiveness. As of January 2008, 1080 communities, representing only 5% of all the NFIP communities have enrolled in CRS. Little empirical evidence exists to shed light on what factors influence the establishment of local hazard mitigation projects. To fill this gap, we propose to analyze flood hazard mitigation projects in 37 North Carolina coastal counties between 2002 and 2008. Specifically, we will examine the influence of physical, risk, and socioeconomic factors on coastal community hazard mitigation decisions as reflected in the CRS score. Ultimately, our project will forge a better understanding of community decision making, as related to natural hazards. (PDF contains 4 pages)
Resumo:
This translation includes selected passages of a longer paper on Mastigophora and Rhizopoda found in saline lakes Weissovo and Repnoie. The translation focuses on describing taxonomy and morphology of Ochromonas species and Pedinella. Plates and figures of the original paper are not included in the translation.
Resumo:
Identification keys to families of Cladocera and to subfamilies, genera, species and subspecies of Macrothricidae and Moinidae are given. This translation does not include ecological notes or illustrations.
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Ecosystem level models are motivated by some combination of scientific and practical concerns. Those models motivated by practical concerns are likely to bear little historical relation to previous models. Mechanisms of interaction between particular species and their ecosystems vary enormously. Some species literally construct their own ecosystems. Others have more or less complex and important interactions with other species so that their presence or absence may alter the ecosystem. Prior information about the natural history of particular species can make ecosystem investigations quicker, cheaper, and more effective. The optimal resource for preparing to deal with the unlimited diversity of questions asked of ecologists would be a large' computerized databank of natural history observations for as many species as possible.
Resumo:
Rockfish (Sebastes spp.) biomass is difficult to assess with standard bottom trawl or acoustic surveys because of their propensity to aggregate near the seafloor in highrelief areas that are inaccessible to sampling by trawling. We compared the ability of a remotely operated vehicle (ROV), a modified bottom trawl, and a stereo drop camera system (SDC) to identify rockfish species and estimate their size composition. The ability to discriminate species was highest for the bottom trawl and lowest for the SDC. Mean lengths and size distributions varied among the gear types, although a larger number of length measurements could be collected with the bottom trawl and SDC than with the ROV. Dusky (S. variabilis), harlequin (S. variegatus), and northern rockfish (S. polyspinis), and Pacific ocean perch (S. alutus) were the species observed in greatest abundance. Only dusky and northern rockfish regularly occurred in trawlable areas, whereas these two species and many more occurred in untrawlable areas. The SDC was able to resolve the height of fish off the seafloor, and some of the rockfish species were observed only near the seafloor in the acoustic dead zone. This finding is important, in that fish found exclusively in the acoustic dead zone cannot be assessed acoustically. For these species, methods such as bottom trawls, long-lines, or optical surveys using line transect or area swept methods will be the only adequate means to estimate the abundance of these fishes. Our results suggest that the selection of appropriate methods for verifying targets will depend on the habitat types and species complexes to be examined.
Resumo:
As in many tropical countries, subsistence fishers in Samoa live in discrete communities which have a high level of marine knowledge and some degree of control of adjacent waters. These factors provide an ideal basis for motivating communities to manage their marine resources. In Samoa, a community-based fisheries extension program encouraged each village community to define its key problems, discuss causes, propose solutions and take appropriate actions. Various village groups provided information which was recorded as problem/solution trees. The extension process culminated in a Village-Fisheries Management Plan which listed the resource management and conservation undertakings of the community. Undertakings range from enforcing laws banning destructive fishing methods to protecting critical marine habitats. Within the first eighteen months, the extension process commenced in 57 villages of which 40 have produced Village Fisheries Management Plans. An unexpectedly large number (32) or these villages chose to establish Marine Protected Areas, the first community-owned marin reserves in the country.
Resumo:
This article contains a discussion paper on the use of exotic species and genetically modified organisms in aquaculture and enhanced fisheries, together with a summary of ICLARM's (International Center for Living Aquatic Resources Management, Philippines) current position on this important topic.
Resumo:
Despite considerable conservation efforts, many reef fish fisheries around the world continue to be in peril. Many are vulnerable to overexploitation because they have predictable and highly aggregated spawning events. In U.S. Caribbean waters, fishery managers are increasingly interested in advancing the use of closed areas as a means for rebuilding reef fisheries, protecting coral reef habitats, and furthering ecosystem-based management while maintaining the sustained participation of local fishing communities. This study details small-scale fishermen’s views on the Caribbean Fishery Management Council’s proposals to lengthen the current Bajo de Sico seasonal closure off the west coast of Puerto Rico to afford additional protection to snapper-grouper spawning populations and associated coral reef habitats. Drawing on snowball sampling techniques, we interviewed 65 small-scale fishermen who regularly operate in the Bajo de Sico area. Snowball sampling is a useful method to sample difficult-to-find populations. Our analysis revealed that the majority of the respondents opposed a longer seasonal closure in the Bajo de Sico area, believing that the existing 3-month closure afforded ample protection to reef fish spawning aggregations and that their gear did not impact deep-water corals in the area. Whilst fishermen’s opposition to additional regulations was anticipated, the magnitude of the socio-economic consequences described was unexpected. Fishermen estimated that a year round closure would cause their gross household income to fall between 10% and 80%, with an average drop of 48%. Our findings suggest that policy analysts and decision-makers should strive to better understand the cumulative impacts of regulations given the magnitude of the reported socio-economic impacts; and, more importantly, they should strive to enhance the existing mechanisms by which fishermen can contribute their knowledge and perspectives into the management process.