986 resultados para kerala Fishery
Resumo:
Sand Creek is the most significant recreational fishery in Delaware County because of its location to Manchester and Lake Delhi. It is a feeder stream for game fish to the main stem of the Maquoketa River which is limited by the dams at Manchester and Lake Delhi. Sand Creek encompasses 16,045 acres and is dominated by row crop agriculture. It is being impacted by sediment, nutrients and E coli bacteria. Sand Creek will be a good example for habitat impaired watershed. The purpose of this project is to decrease the amount of sediment and nutrients reaching Sand Creek and to increase the habitat in Sand Creek to make it a better spawning and growing area for the fish and the food chain for the fish. The objectives of this project are to reduce sediment delivery by 40%, to improve in-stream habitat on 40% of identified critical areas and implement an information/education program. The project will install 3,800 acres of new no-till planting, 6 water and sediment control basins, 4,000 feet of terraces, 20,000 feet of improved or new waterways, 3,200 feet of streambank/ habitat enhancement, 4,500 feet of livestock exclusion fencing and 6 acres of wetlands.
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Two sections of the Yellow River have been named to the State of Iowa’s 303d list of impaired waters. The listing reflects streams with pollution problems linked to habitat alterations, in addition to those with potential disease causing bacteria, viruses and parasites. This fact, combined with local knowledge of water quality problems, shows the need for land treatment practices and habitat improvement measures. This project would target the Yellow River watershed, which totals approximately 49,800 acres. Areas that drain directly into the Yellow River mainstream will be targeted. Individually, these areas are too small to be considered sub-watersheds. This project will assess the drainage areas for active gullies and prioritize grade stabilization structures based upon severity and impact on the fishery. Funding would be utilized to target high priority grade stabilization structure sites and provide cost-share for those projects. A prerequisite for cost-share allocation is 75% of the land contributing to the drainage area must have some form of treatment in place. The Allamakee SWCD has received an EPA Region 7 Grant toward grade stabilization structures in the same area. Landowners have indicated that 75% cost-share is necessary to implement practices. To meet this request, the EPA funding would be used at a 15% cost-share rate if matched with 60% cost-share from WIRB funding. If matched with Federal EQIP funds, 25% of funds obtained from WIRB would be used. If other funds were depleted, WIRB funds would be utilized for the entire 75% cost-share.
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Artificial reefs have barely been used in Neotropical reservoirs (about five studies in three reservoirs), despite their potential as a fishery management tool to create new habitats and also to understand fish ecology. We experimentally assessed how reef material (ceramic, concrete, and PVC) and time modulated fish colonization of artificial reefs deployed in Itaipu Reservoir, a large reservoir of the mainstem Parana´ River, Brazil. Fish richness, abundance, and biomass were significantly greater in the reef treatments than at control sites. Among the experimental reefs, ceramic followed by the concrete treatments were the materials most effectively colonized, harboring the majority of the 13 fish species recorded. Although dependent on material type, many of the regularities of ecological successions were also observed in the artificial reefs, including decelerating increases in species richness, abundance, mean individual size, and species loss rates with time and decelerating decreases of species gain and turnover rates. Species composition also varied with material type and time, together with suites of life history traits: more equilibrium species (i.e., fishes of intermediate size that often exhibit parental care and produce fewer but larger offspring) of the Winemiller-Rose model of fish life histories prevailed in later successional stages. Overall, our study suggests that experimental reefs are a promising tool to understand ecological succession of fish assemblages, particularly in tropical ecosystems given their high species richness and low seasonality
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The TBA test is essential to quality control of fat-containing food, being the test most applied to evaluate lipid peroxidation in fishery, meat and poultry products. It estimates malonaldehyde, a secondary oxidation product, by reacting with 2-thiobarbituric acid, forming a coloured complex, measured spectrophotometrically atlambda = 532 nm. Results are expressed as mg malonaldehyde per kg sample or frequently as "TBA value". There are four ways of quantifying it: by lipid extraction, direct heating, distillation or heat-acid extraction. This review intends to point out traditional, modified and alternative TBA test methods, besides enumerating advantages and drawbacks of each one.
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Genetic diversity is one of the levels of biodiversity that the World Conservation Union (IUCN) has recognized as being important to preserve. This is because genetic diversity is fundamental to the future evolution and to the adaptive flexibility of a species to respond to the inherently dynamic nature of the natural world. Therefore, the key to maintaining biodiversity and healthy ecosystems is to identify, monitor and maintain locally-adapted populations, along with their unique gene pools, upon which future adaptation depends. Thus, conservation genetics deals with the genetic factors that affect extinction risk and the genetic management regimes required to minimize the risk. The conservation of exploited species, such as salmonid fishes, is particularly challenging due to the conflicts between different interest groups. In this thesis, I conduct a series of conservation genetic studies on primarily Finnish populations of two salmonid fish species (European grayling, Thymallus thymallus, and lake-run brown trout, Salmo trutta) which are popular recreational game fishes in Finland. The general aim of these studies was to apply and develop population genetic approaches to assist conservation and sustainable harvest of these populations. The approaches applied included: i) the characterization of population genetic structure at national and local scales; ii) the identification of management units and the prioritization of populations for conservation based on evolutionary forces shaping indigenous gene pools; iii) the detection of population declines and the testing of the assumptions underlying these tests; and iv) the evaluation of the contribution of natural populations to a mixed stock fishery. Based on microsatellite analyses, clear genetic structuring of exploited Finnish grayling and brown trout populations was detected at both national and local scales. Finnish grayling were clustered into three genetically distinct groups, corresponding to northern, Baltic and south-eastern geographic areas of Finland. The genetic differentiation among and within population groups of grayling ranged from moderate to high levels. Such strong genetic structuring combined with low genetic diversity strongly indicates that genetic drift plays a major role in the evolution of grayling populations. Further analyses of European grayling covering the majority of the species’ distribution range indicated a strong global footprint of population decline. Using a coalescent approach the beginning of population reduction was dated back to 1 000-10 000 years ago (ca. 200-2 000 generations). Forward simulations demonstrated that the bottleneck footprints measured using the M ratio can persist within small populations much longer than previously anticipated in the face of low levels of gene flow. In contrast to the M ratio, two alternative methods for genetic bottleneck detection identified recent bottlenecks in six grayling populations that warrant future monitoring. Consistent with the predominant role of random genetic drift, the effective population size (Ne) estimates of all grayling populations were very low with the majority of Ne estimates below 50. Taken together, highly structured local populations, limited gene flow and the small Ne of grayling populations indicates that grayling populations are vulnerable to overexploitation and, hence, monitoring and careful management using the precautionary principles is required not only in Finland but throughout Europe. Population genetic analyses of lake-run brown trout populations in the Inari basin (northernmost Finland) revealed hierarchical population structure where individual populations were clustered into three population groups largely corresponding to different geographic regions of the basin. Similar to my earlier work with European grayling, the genetic differentiation among and within population groups of lake-run brown trout was relatively high. Such strong differentiation indicated that the power to determine the relative contribution of populations in mixed fisheries should be relatively high. Consistent with these expectations, high accuracy and precision in mixed stock analysis (MSA) simulations were observed. Application of MSA to indigenous fish caught in the Inari basin identified altogether twelve populations that contributed significantly to mixed stock fisheries with the Ivalojoki river system being the major contributor (70%) to the total catch. When the contribution of wild trout populations to the fisheries was evaluated regionally, geographically nearby populations were the main contributors to the local catches. MSA also revealed a clear separation between the lower and upper reaches of Ivalojoki river system – in contrast to lower reaches of the Ivalojoki river that contributed considerably to the catch, populations from the upper reaches of the Ivalojoki river system (>140 km from the river mouth) did not contribute significantly to the fishery. This could be related to the available habitat size but also associated with a resident type life history and increased cost of migration. The studies in my thesis highlight the importance of dense sampling and wide population coverage at the scale being studied and also demonstrate the importance of critical evaluation of the underlying assumptions of the population genetic models and methods used. These results have important implications for conservation and sustainable fisheries management of Finnish populations of European grayling and brown trout in the Inari basin.
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Kirjallisuusarvostelu
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The genetic variability of the "curimba", Prochilodus lineatus, from three locations in the Paraná river basin, was investigated by starch gel electrophoresis. A total of 160 specimens were analyzed for 19 enzymes, 12 of which permitted successful interpretation of electrophoretic patterns. Eighteen loci were identified and six of them proved to be polymorphic (EST-1*, EST-2*, IDH-1*, PGM-1*, PGM-2*, LDH-2*). Mean heterozygosity was considered high (13%) by comparison with the literature. A low level of differentiation was found among subpopulations, with mean F ST = 0.018. Values of genetic distance and genetic identity suggest that, at least along this stretch of the river, P. lineatus comprises a single breed with high gene flow. This analysis has important implications for fishery management, aquaculture, and conservation of the stocks
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The South American sea lion, Otaria flavescens, is widely distributed along the Pacific and Atlantic coasts of South America. However, along the Brazilian coast, there are only two nonbreeding sites for the species (Refúgio de Vida Silvestre da Ilha dos Lobos and Refúgio de Vida Silvestre do Molhe Leste da Barra do Rio Grande), both in Southern Brazil. In this region, the species is continuously under the effect of anthropic activities, mainly those related to environmental contamination with organic and inorganic chemicals and fishery interactions. This paper reports, for the first time, the genetic diversity of O. flavescens found along the Southern Brazilian coast. A 287-bp fragment of the mitochondrial DNA control region (D-loop) was analyzed. Seven novel haplotypes were found in 56 individuals (OFA1-OFA7), with OFA1 being the most frequent (47.54%). Nucleotide diversity was moderate (π = 0.62%) and haplotype diversity was relatively low (67%). Furthermore, the median joining network analysis indicated that Brazilian haplotypes formed a reciprocal monophyletic clade when compared to the haplotypes from the Peruvian population on the Pacific coast. These two populations do not share haplotypes and may have become isolated some time back. Further genetic studies covering the entire species distribution are necessary to better understand the biological implications of the results reported here for the management and conservation of South American sea lions.
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This study aimed to verify the hygienic-sanitary working practices and to create and implement a Hazard Analysis Critical Control Point (HACCP) in two lobster processing industries in Pernambuco State, Brazil. The industries studied process frozen whole lobsters, frozen whole cooked lobsters, and frozen lobster tails for exportation. The application of the hygienic-sanitary checklist in the industries analyzed achieved conformity rates over 96% to the aspects evaluated. The use of the Hazard Analysis Critical Control Point (HACCP) plan resulted in the detection of two critical control points (CCPs) including the receiving and classification steps in the processing of frozen lobster and frozen lobster tails, and an additional critical control point (CCP) was detected during the cooking step of processing of the whole frozen cooked lobster. The proper implementation of the Hazard Analysis Critical Control Point (HACCP) plan in the lobster processing industries studied proved to be the safest and most cost-effective method to monitor each critical control point (CCP) hazards.
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The marine bioprocessing industry offers great potential to utilize byproducts for fish meal replacement in aquafeeds. Jumbo squid is an important fishery commodity in Mexico, but only the mantle is marketed. Head, fins, guts and tentacles are discarded in spite of being protein-rich byproducts. This study evaluated the use of two jumbo squid byproduct hydrolysates obtained by acid-enzymatic hydrolysis (AEH) and by autohydrolysis (AH) as ingredients in practical diets for shrimp. The hydrolysates were included at levels of 2.5 and 5.0% of the diet dry weight in four practical diets, including a control diet without hydrolysate. Shrimp growth and survival were not significantly affected by the dietary treatments. Postharvest quality of abdominal muscle was evaluated in terms of proximate composition and sensory evaluation. Significantly higher crude protein was observed in the muscle of shrimp fed the highest hydrolysate levels, AH 5% (204.8 g kg- 1) or AEH 5% (201.3 g kg- 1). Sensory analysis of cooked muscle showed significant differences for all variables evaluated: color, odor, flavor, and firmness. It was concluded that Jumbo squid byproducts can be successfully processed by autohydrolysis or acid-enzymatic hydrolysis, and that up to 5.0% of the hydrolysates can be incorporated into shrimp diets without affecting growth or survival.
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Abstract Tilapia, salmon, tuna and sardine meals were prepared to develop and analyze extruded snacks with residue meal from fish processing. Residue meals were included in five types of corn snacks: control (0% fish meal) and four with 9% tilapia, salmon, tuna and sardine meals. Although moisture, lipids and carbohydrates rates did not differ among the snacks, protein rates increased with the increment of fish meal, reaching 11.85% in the tuna snack. Tuna and sardine snacks had the highest iron levels. The most abundant fatty acids were linoleic, oleic, palmitic, linolenic and stearic acids, with sardine, salmon and tuna snacks presenting the highest values of n-3 series fatty acids. Greater luminosity rate was reported for salmon snack, followed by tilapia, tuna and sardine snacks. The highest sensory acceptance index was verified in tilapia (78.07%) and salmon (72.40%). A 9% addition of residue meals of tilapia, salmon and tuna improved the nutritional value of the snacks.
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Dans le domaine de la pêche, les initiatives d’écolabellisation ont été perçues comme un moyen simultané de maintenir la productivité et la valeur économique de la pêche tout en améliorant sa gestion et la conservation de la biodiversité marine. Cet article présente les principaux écolabels dans le domaine de la pêche ainsi que les enjeux actuellement associés au développement de ces démarches volontaires.
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La perchaude (Perca flavescens) constitue une ressource socioéconomique de grande importance dans le Lac Saint-Pierre (Québec, Canada). Bien que ce lac fluvial soit désigné réserve de la biosphère par l’UNESCO, le statut de la perchaude est préoccupant. Afin de permettre à l’espèce de persister en fonction des diverses pressions anthropiques, il est important de comprendre sa dynamique populationnelle et les mécanismes qui en sont responsables. La perchaude est connue pour sa philopatrie ; le fait de toujours se reproduire à son site de naissance peut entraîner la subdivision d’une espèce en de multiples populations, où chacune pourra être pourvue d’adaptations locales distinctes. Il est possible d’étudier ces processus à l’aide des signaux génétiques associés à la reproduction des individus. Toutefois, une faible différentiation génétique entre les populations du Lac Saint-Pierre est envisagée en raison de la colonisation récente du système (moins de 8000 ans). L’objectif de cette étude est de déterminer s’il existe plusieurs populations de perchaude dans le Lac Saint-Pierre. Les simulations réalisées ont révélé que l’utilisation de marqueurs AFLP (amplified fragment length polymorphism), permettant une analyse globale du génome, affiche une meilleure détection de la différentiation des populations que celle des marqueurs microsatellites. Afin d’associer les individus à leur site de naissance, la méthode d’AFLP et des microsatellites ont été utilisées sur des larves capturées suite à l’éclosion des oeufs. Trois analyses distinctes d’AFLP ont indiqué une corrélation entre la composition génétique des individus et des sites géographiques, confirmant ainsi la présence de plusieurs populations sympatriques dans le Lac Saint-Pierre, découlant vraisemblablement de la philopatrie de l’espèce. L’absence de différentiation génétique relatée par les marqueurs microsatellites vient confirmer l’importance du choix des marqueurs génétiques. Bien que la différentiation génétique observée soit relativement faible, la gestion de la perchaude devrait tenir compte de la dynamique des populations distinctes dans ce système.
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Depuis les années 1980, les archéologues ont remarqué l'originalité des collections de céramiques trouvées sur des sites occupés par les pêcheurs basques au cours du XVIe au XVIIIe siècle sur les côtes atlantiques du Canada. Le site de Red Bay (Labrador) a été le premier à fournir une riche collection de terre cuites communes, majoliques et grès, qui ont permis aux archéologues de reconnaître une tradition céramique distincte. Pendant plus de deux siècles, ces céramiques constituent un fil conducteur qui montre la permanence des activités commerciales basques au Canada. En utilisant une approche mutualiste et comparative de quatre sites de pêche basque (Red Bay (1530-1580), Anse-à-la-Cave (1580-1630), Petit-Mécatina (1630-1713), Pabos (1713- 1760)) et leurs ports d’attache dans l’Europe atlantique, nous observons comment à partir du milieu du XVIe siècle, l’ensemble des céramiques se transforme d'un endroit à l’autre sans perdre son air distinctif jusqu'au début du XVIIIe siècle quand les témoins des céramiques basques changent radicalement. Finalement, une perspective globale qui relie les deux côtes atlantiques par le biais de ces matériaux céramiques nous aide à mieux connaître les réseaux d'approvisionnement liés aux traversées de pêche et l’espace économique complexe qui s’articule aux routes maritimes et de l’intérieur. Ces deux éléments se veulent essentiels à la compréhension de l'expansion outremers, ses materiaux laissés et son rôle dans l'économie mondiale au début de l'époque moderne.
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Le Teyyam est un rituel de possession hindouiste du Kerala (Inde du Sud) qui nécessite une pratique intransigeante : restrictions, jeûnes, exploits physiques, résistance à la chaleur du feu. Vêtus de costumes spectaculaires, des performeurs de caste intouchable dansent l’épée à la main, au son des tambours frénétiques, et font entendre la parole du dieu qu’ils incarnent; ils auront même le droit de critiquer le système des castes devant la communauté assemblée, le temps d’une inversion rituelle. Alors qu’autrefois il s’agissait d’un devoir de caste associé à une grande précarité, aujourd’hui il s’agit d’un métier que l’on peut choisir d’exercer ou non. Bien qu’on ait déploré un manque de relève à cause des conditions jugées trop difficiles, il y a toutefois de jeunes hommes qui ont décidé de poursuivre cette tradition ancestrale. Au Kerala, de nombreux jeunes aspirent à la classe moyenne et misent sur l’éducation pour espérer un bon emploi, il y a des opportunités, mais pas pour tous, et surtout beaucoup de compétition. C’est dans ce contexte que de jeunes hommes éduqués souhaitent poursuivre une tradition qu’ils admirent et dont ils sont fiers, mais sans avoir à sacrifier leurs chances de réussite sociale. Quelles sont leurs aspirations, quel sens donnent-ils à ce qu’ils souhaitent accomplir? Traditionnellement les relations de patronage dans le Teyyam ont été très dures sous le joug du système des castes, qu’en est-il aujourd’hui? Comment ces performeurs arrivent-il à négocier la réalisation de leurs aspirations dans les coulisses du Teyyam?