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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
381

Inconsistencia legal e ineficiencia del régimen administrativo sancionador por pesca de tallas menores en la actividad pesquero industrial / Legal inconsistency and inefficiency of the sanctioning administrative regime for fishing of smaller sizes in the industrial fishing activity

Miranda Arévalo, Graciela de los Milagros, Quispe Lobatón, Jorge Alberto, Rozas Olivera, Hortencia Rebeca 12 December 2018 (has links)
En el desarrollo de las faenas pesqueras de la flota industrial se ha identificado un tipo de infracción relacionada con la pesca de tallas menores o juveniles, que es sancionada con multas y decomisos. El sustento normativo de la infracción y la consecuente sanción es la sostenibilidad pesquera que, en este caso, tiene como propósito proteger las tallas menores de anchoveta para asegurar su reproducción. Usando el método de investigación descriptiva con enfoque cualitativo, en la presente investigación se demostrará que la aplicación de dicho régimen sancionador no ha contribuido a la sostenibilidad pesquera, sino que habría motivado descartes en el mar, escondiendo la infracción, y puede haber provocado contaminación en el medio marino, debido a que los efectos del descarte no se han llegado a medir. En el análisis de las resoluciones sancionadoras, en contraste con estudios de la masa hidrobiológica, con las evidencias de la existencia de volúmenes aptos para pesca, la asignación de cuotas de pesca, así como las decisiones de inicio y cierre de temporada con base en estudios científicos del rendimiento máximo sostenible, y las medidas preventivas de cierre y veda de zonas, se concluye que estas medidas han sido más efectivas que las sanciones aplicadas a la pesca de tallas menores. Esto, para garantizar la sostenibilidad pesquera de la anchoveta peruana. / In the development of the fishing operations of the industrial fleet, a type of infraction related to the fishing of smaller or juvenile sizes has been identified, which is sanctioned with fines and seizures. The normative support of the infraction and the consequent sanction is the fishing sustainability that, in this case, has the purpose of protecting the smaller sizes of anchoveta to ensure its reproduction. Using the method of descriptive research with a qualitative approach, in the present investigation it will be demonstrated that the application of this sanctioning regime has not contributed to fisheries sustainability, but would have motivated discards at sea, hiding the infraction, and may have caused contamination in the marine environment, because the effects of discarding have not been measured. In the analysis of the sanctioning resolutions, in contrast with studies of the hydrobiological mass, with the evidences of the existence of suitable volumes for fishing, the allocation of fishing quotas, as well as the decisions of beginning and closing of season based on studies maximum sustainable yield scientists, and the preventive measures of closure and closure of zones, conclude that these measures have been more effective than the sanctions applied to fishing for smaller sizes. This, to guarantee the fishing sustainability of the Peruvian anchoveta. / Trabajo de investigación
382

Environmental stochasticity and density dependence in animal population models

Samaranayaka, Ari, n/a January 2006 (has links)
Biological management of populations plays an indispensable role in all areas of population biology. In deciding between possible management options, one of the most important pieces of information required by population managers is the likely population status under possible management actions. Population dynamic models are the basic tool used in deriving this information. These models elucidate the complex processes underlying the population dynamics, and address the possible consequences/merits of management actions. These models are needed to guide the population towards desired/chosen management goals, and therefore allow managers to make informed decisions between alternative management actions. The reliability that can be placed on inferences drawn from a model about the fate of a population is undoubtedly dependent on how realistically the model represents the dynamic process of the population. The realistic representation of population characteristics in models has proved to be somewhat of a thorn in the side of population biologists. This thesis focuses in particular on ways to represent environmental stochasticity and density dependence in population models. Various approaches that are used in building environmental stochasticity into population models are reviewed. The most common approach represents the environmental variation by changes to demographic parameters that are assumed to follow a simple statistical distribution. For this purpose, a distribution is often selected on the basis of expert opinion, previous practice, and convenience. This thesis assesses the effect of this subjective choice of distribution on the model predictions, and develops some objective criteria for that selection based on ecological and statistical acceptability. The more commonly used distributions are compared as to their suitability, and some recommendations are made. Density dependence is usually represented in population models by specifying one or more of the vital rates as a function of population density. For a number of reasons, a population-specific function cannot usually be selected based on data. The thesis develops some ecologically-motivated criteria for identifying possible function(s) that could be used for a given population by matching functional properties to population characteristics when they are known. It also identifies a series of properties that should be present in a general function which could be suitable for modelling a population when relevant population characteristics are unknown. The suitability of functions that are commonly chosen for such purposes is assessed on this basis. I also evaluate the effect of the choice of a function on the resulting population trajectories. The case where the density dependence of one demographic rate is influenced by the density dependence of another is considered in some detail, as in some situations it can be modelled with little information in a relatively function-insensitive way. The findings of this research will help in embedding characteristics of animal populations into population dynamics models more realistically. Even though the findings are presented in the context of slow-growing long-lived animal populations, they are more generally applicable in all areas of biological management.
383

Analysis of seabird by-catch in the Australian Fishing Zone using Japanese longline fishery observer data

Klaer, Neil E., n/a January 1998 (has links)
Data collected by Australian observers, combined with logbook data supplied by all Japanese vessels fishing in the Australian Fishing Zone were used to estimate the total seabird catch and catch rates (and associated variances) within the Australian Fishing Zone by season and area. The species composition of subsamples of captured seabirds was used in conjunction with the estimates of total by-catch to provide estimates of by-catch by species. The total by-catch of all seabird species by Japanese longline within Australian waters was estimated to be 2,981 (cv 17%) for the 1992 fishing year, 3,590 (cv 15%) in 1993 and 2,817 (cv 19%) in 1994. However, the observed seabird bycatch may underestimate the total number of seabirds killed by 27%. The increase in total seabird by-catch between 1992 and 1993 is partly due to the use of monofilament nylon longline gear by two vessels in 1993, and the decrease from 1993 to 1994 was mainly due to a corresponding reduction in fishing effort. For the three years examined, 78% of the total seabird by-catch was albatrosses, with black-browed albatross (Diomedea melanophrys) and shy albatross (D. cauta) caught in the greatest numbers. Catches of yellow-nosed albatross (D. chlororhynchos), wandering albatross (D. exulans}, and grey-headed albatross (D. chrysostoma) were also substantial. The proportions of individual species caught showed considerable inter-annual variability. Most seabirds caught and killed by longline fishing are captured during line setting. Data collected by the observers were also used to determine the influence of various environmental factors and mitigation measures on seabird catch rates. Generalised linear models were used to determine the statistical significance of the effect of each factor on the seabird catch rate. Results show that the environmental factor that has the most influence is whether line setting was carried out at night or during the day. For the data examined, the chance of catching seabirds during day sets was five times greater than for night sets. For night sets, the chance of catching seabirds during the full half-phase of the moon was five times greater than during the new half-phase. Other environmental factors with significant effects were the area and season fished. Wind, cloud and sea conditions were not found to have a significant influence. Considerable variation in the seabird by-catch rate among vessels was found, which is probably due to differences in their implementation of mitigation measures, as well as the clumped distribution of seabirds by area and time. Interannual variation in the by-catch rate was found to be statistically significant but the differences among years was small in comparison to other factors. An examination of the influence of mitigation measures for sets made during the day in summer in the Tasmanian area showed that the level of bait thawing and unidentified factors related to individual vessels were most significant in determining the seabird by-catch rate, followed by the use of a bait throwing device. It was not possible to examine the influence of the use of bird scaring tori poles and lines as these were used during all sets examined in detail. For this data set, the amount of cloud cover had an influence, while moon phase, sea conditions and wind strength did not.
384

Gene fishing in Cataglyphis fortis – Identification of genes inthe desert ant

Münzner, Ulrike January 2009 (has links)
<p>The desert ant Cataglyphis fortis lives in the Sahara desert where it is exposed to extreme temperatures up to 70° C. In other words, the organism is considered as a thermophile. Until now the genome remains unknown but the fact that C. fortis provides heat stable proteins makes it very interesting in the field of protein studies and maybe even therapeutical research later on. This thesis focuses on trying to find genes that are expressed in C. fortis. Different genes were chosen and capable primers designed. After fishing for the enzyme GAPDH a fragment was found and sequenced. The sequence showed 31% homology on amino acid level with protein disulfide isomerase (PDI) in Apis mellifera (honey bee) and Drosophila melanogaster (fruitfly). The received sequence can be used to design new primers that match exactly. Gene fishing can also be continued by using the other primers that were designed during this project.</p>
385

Recreational demand for fishing in the Yellowstone National Park Area : a travel cost model

Lowe, Scott Elliot 18 June 1997 (has links)
Potential policy decisions regarding fly fishing in the Yellowstone National Park Area could severely impact the enjoyment possibilities of many of its users. In order to determine the magnitude of the impact, this paper applies a form of the basic travel cost model developed by Bell and Leeworthy [JEEM. 18,189-205 (1990)] to fishing sites in the Yellowstone National Park Area. Bell and Leeworthy have argued that consumer demand for the time spent at a recreation site is inversely related to on-site cost per day, and may be positively related to travel cost per trip. The paper discusses relevant literature on the method, presents background information on the site, and generates a demand curve for users of the resource. A consumer surplus measurement is then derived from the resulting demand data, which gives an estimate for the value of the resource; the consumer surplus is determined to be roughly $751.88 per day spent at the site. The assumptions of the model are then discussed, and an assessment is made of the potential policy implications. / Graduation date: 1998
386

Cherokee fishing ethnohistorical, ethnoecological, and ethnographic perspectives /

Altman, Heidi M., January 2002 (has links) (PDF)
Thesis (Ph.D.)--University of California, Davis, 2002. / Includes bibliographical references.
387

Population dynamics of the raggedtooth shark (Carcharias taurus) along the east coast of South Africa

Dicken, Matthew Laurence. January 2006 (has links)
Thesis (Ph. D.)--Rhodes University, 2006. / Title from PDF t.p. (viewed on Apr. 12, 2007). Includes bibliographical references (p. 184-207).
388

Spatial Characterization of Puerto Rican Commercial Fisheries: Gear Usage Across Habitat Classes and Bathymetry Ranges

Koeneke, Roberto 09 May 2011 (has links)
The spatial characterization of Puerto Rican commercial fisheries describing fishing gear use in relation to habitat classes and bathymetry ranges was achieved through the collection and analysis of spatial fisheries data. An extensive field data gathering session was conducted in the entire Puerto Rican territory during the summer months of 2009, from June to October. The field data was digitized and analyzed using geographic information systems (GIS) and computer spreadsheet software, and gear usage charts and graphs, fishing grounds maps, and fishing intensity maps were produced for four gear categories: line, net, dive, and trap gears. Patterns and evidence of likely relationships linking gear usage and benthic habitat, and between gear utilization and water depth ranges, were presented. The importance of the spatial characterization of the commercial fishery for Puerto Rican fisheries management, and other recommendations were given within the concluding chapter.
389

The spawning salmon as a resource by recreational use : the case of the wild Baltic salmon and conditions for angling in north Swedish rivers

Appelblad, Håkan January 2001 (has links)
The aim of the thesis is to analyse the preconditions for increasedsalmon angling in the remaining wild salmon rivers in Upper Norrland in northernSweden, as well as to evaluate the present and possible future impacts on the localeconomy. It includes the identification of the internal and external conditions, in what ishere called the Salmon Utilisation Landscape, that influence the present use as well asfuture development of the Baltic salmon as a resource in angling. The empirical materialsderive from two mail surveys, 1) a survey of anglers in the River Byske and 2) a jointNordic survey on the economic value of recreational fishing.Interest in recreational fishing is widespread in Sweden. About 35 % of adultSwedes fish for recreation. Recreational fishery and angling can be seen as one expressionof the urbanised society's need for contact with nature and outdoor recreation. Salmonangling is one part of recreational fishery. Salmon are considered by many to be the 'biggame' of angling. Salmon anglers are often the most devoted kind of anglers, investingconsiderable resources into this leisure activity. The subgroup of Swedish salmon anglingspecialists is estimated at 10-30,000 persons. The wider category of Active River anglersconsists of approximately 170,000 persons.Salmon fishing in the River Byske has turned out to be representative of salmonangling in Upper Norrland, comparable with other high-class Scandinavian salmon rivers.The growing proportion of remote anglers in the 1990s indicates that the Byske hasbecome a rather specialised angling water. The groups of Fishing tourists and Home fishersmake up two distinctive categories. Fishing tourists fish more intensively, have higher dailyexpenditures and show higher consumer surplus. They fish the river almost entirely forsalmon in. On the other hand, Home fishers to a large extent claim the right to fish fordecent prices and without any particular restrictions. During the 1990s, the average annualincome to the local economy of Byske river valley derived from salmon angling fishingtourism was about 850,000 SEK.Many river habitats have been depleted during the 20th century and many salmonstocks were exterminated by severe degeneration factors linked to industrialisation. To thisis added the over-fishing on wild stocks of salmon and the mortality syndrome, M74. Theavailable estimates of the potential production of wild salmon smolt in Upper Norrlandaggregates close to 1.2 million. This can be converted to an angling activity of some250,000 fishing days.On the basis of the prevailing cost level, the potential angling activity in UpperNorrland would amount to a direct annual turnover of 75 million SEK, however theimpact caused by fishing tourism is likely to remain within the interval of 10 - 30 millionSEK. The Active River anglers' average willingness to pay for annual access to a salmon andsea trout scenario was 1,100 SEK per capita. There is a widespread attitude among manyanglers that fishing should be accessible for all and prices should be kept low. In theNordic context such opinions are especially evident among Swedish anglers in general, butless frequent among devoted salmon anglers. / digitalisering@umu
390

Exploring a shared history : Indian-White relations between Fishing Lake First Nation and Wadena, 1882-2002

Nicholat, Christa Leanne 03 July 2007
A great deal of literature exists that documents the nature and development of relations between Native and Newcomer groups in what is today the Eastern and Maritime regions of Canada. By comparison, however, studies which examine interaction between these two groups in Canada's prairie region are considerably lacking. Although a sufficient amount has been written about prairie Indian peoples and their experiences with government officials and policy, relatively little is known about relations between Indian reserve communities and neighbouring immigrant communities, particularly during the early years of settlement. A survey of existing sources suggests that during this time Indian people were simply settled on reserves and immigrant towns grew up around them, each, it seems, operating in complete isolation from the other.<p>This thesis aims to fill this gap in the historical literature by attempting to draw out the essence of the integrated and intertwined elements of the history shared by two prairie communities. The basic aim of this study is to trace the nature and development of relations between Fishing Lake First Nation and Wadena, located in the east central portion of Saskatchewan, from the 1880s to the present. Exploring a Shared History seeks to provide a more thorough understanding of and broader perspective on an important, yet much-neglected, facet of the region's history.

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