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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.
71

Ordenamento da pesca de lagosta (gÃnero: Panulirus) e a recuperaÃÃo da sustentabilidade das pescarias no litoral do Brasil: uma proposta inovadora do ordenamento pesqueiro / Lobster fisheries management (genus: Panulirus) recovery and sustainability of coastal fisheries in Brazil: an innovative proposal of fishery management

Paulo Parente Lira Cavalcante 07 February 2014 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / Esta tese aborda o ordenamento da pesca da lagosta do gÃnero Panulirus, o principal produto de exportaÃÃo da pesca do Brasil, desde meados da dÃcada de 1950, propondo um conjunto de medidas inovadoras para implantaÃÃo a partir de 2015. Està dividida em trÃs CapÃtulos. O CapÃtulo 1 trata do Ordenamento da pesca da lagosta no Brasil, com o histÃrico das medidas de ordenamento, base cientÃfica e uma discussÃo dos sucessos, frustraÃÃes e os desafios para uma pescaria sustentÃvel de lagostas no nosso paÃs. O CapÃtulo 2 apresenta uma anÃlise comparativa do ordenamento da pesca de lagosta no Oceano AtlÃntico Centro-Ocidental. Desenvol uma anÃlise comparativa das medidas de ordenamento da pesca de lagosta adotadas no Brasil e aquelas existentes nos paÃses dessa regiÃo, seus Ãxitos e os insucessos na busca de pescarias responsÃveis, com sustentabilidade ambiental, social e econÃmica. Discute o ordenamento da pesca de lagosta, do Plano de GestÃo da Pesca de Lagosta no Golfo do MÃxico e no Litoral Sul dos Estados Unidos; o ordenamento da pesca de lagosta nos paÃses que integram a oganizaÃÃo da Pesca e Aquicultura da America Central â OSPESCA; o ordenamento da pesca de lagosta em Cuba e nos 15 paÃses da Comunidade do Caribe â CARICOM; o ordenamento da pesca de lagosta no MÃxico, ColÃmbia e Venezuela. O CapÃtulo 3 apresenta as propostas inovadoras como a implementaÃÃo do programa de tolerÃncia zero; de quotas individuais transferÃveis; do desembarque compulsÃrio de lagosta viva e do tamanho mÃximo de desembarque, alÃm do retorno da proibiÃÃo de desembarque de lagostas ovadas, como estratÃgia de ordenamento da pesca; alÃm de propor a manutenÃÃo das medidas de defeso; tamanho mÃnimo de desembarque; restriÃÃo Ãs artes de pesca predatÃrias; acesso limitado; rastreamento remoto de embarcaÃÃes de pesca; proteÃÃo dos criadouros naturais; documento de origem da lagosta. Finalmente sÃo relatadas as conclusÃes. / This thesis addresses the spiny lobster (genus Panulirus) fisheries management, the main export fishery product in Brazil, since the mid-1950, proposing at the end a set of innovative measures for implementation from 2015. It is divided into three chapters. Chapter 1 deals with the history of the spiny lobster fisheries management in Brazil, itâs scientific basis and a discussion of the successes, frustrations and challenges for sustainable fishing of lobsters in this country. Chapter 2 presents a comparative analysis of the spiny lobster fishery management in Western Central-Atlantic Area. Develop a comparative analysis of measures for the lobster fishing adopted in Brazil and those existing in the countries of this region, its successes and failures in the search for responsible fisheries, concerning the environmental, social and economic sustainability. Discusses the spiny lobster fisheries management within the Fisheries Management Plan for Lobster in the Gulf of Mexico and the South Coast of the United States, the management of lobster fishing in the countries of the Organization of Fisheries and Aquaculture in Central America â OSPESCA; the lobster fishery management in Cuba and the in the 15 countries of the Caribbean Community â CARICOM, the spiny lobster fisheries management in Mexico, Colombia and Venezuela. Chapter 3 presents innovative proposals such as the implementation of the Zero Tolerance Program, Individual Transferable Quotas, compulsory landing of live lobster and a maximum landing size, plus the return of the ban on lobsters ovate landings, as a strategy planning fishing, besides proposing the continuation of measures of closure, minimum landing size, restriction on predatory fishing gear; limited access; remote tracking of fishing vessels; protection of natural breeding areas and the Lobster Origin Document. Finally the conclusions are reported.
72

Padrões na produtividade e na composição do pescado na pesca artesanal costeira e fluvial brasileira

Lima, Evelyn Gonçalves January 2012 (has links)
Os recursos pesqueiros estão sendo sobre-explotados mundialmente. A pesca pode conduzir ao efeito de cascata trófica e essa exploração pode ser insustentável. Por isso políticas de manejo são urgentes, mas faltam dados para subsidiar tais políticas e nesse sentido, estudos com pescadores artesanais através de entrevistas têm colaborado com o conhecimento sobre a dinâmica pesqueira. A pesca artesanal brasileira é a principal atividade econômica ou de subsistência e o pescado é a maior fonte de proteínas para populações caboclas ribeirinhas amazônicas e populações de caiçaras que vivem na área litorânea da Mata Atlântica. Esta pesquisa analisou padrões ecológicos espaciais e temporais na pesca artesanal brasileira em dois ecossistemas: a costa sudeste da Mata Atlântica e a Amazônia fluvial, tendo como base de dados entrevistas realizadas com pescadores ao longo de vários projetos de pesquisa. No capítulo 1 analisou-se a produtividade pesqueira no litoral sudeste. Foi testada a variação da biomassa média capturada citada pelos entrevistados em função de fatores temporais (idade do pescador e data em que ocorreu sua última pescaria) e espaciais (região aonde se localiza a comunidade do pescador entrevistado). Foram analisadas entrevistas com 423 pescadores, que indicaram que: a) houve uma diminuição na quantidade de peixes capturados ao longo do tempo; b) a biomassa capturada não foi influenciada pelo fator espacial; c) não houve influência da idade do pescador na biomassa capturada mencionada. O capítulo 2 abordou a costa sudeste da Mata Atlântica e a Amazônia fluvial. Foram analisadas a composição dos peixes, através dos nomes populares citados e seu nível trófico médio. Foram analisadas entrevistas com 658 pescadores da Amazônia fluvial (de 1987 a 2006) e 821 pescadores da costa sudeste da Mata Atlântica (de 1986 a 2009) (n=1479 entrevistados). Não houve variação do nível trófico segundo o tempo, porém o nível trófico variou de acordo com os fatores espaciais (ecossistema e região), sendo que o fator que mais influenciou essa variação foi região. Na costa sudeste da Mata Atlântica há possível substituição das espécies de nível trófico similar por outras espécies de mesmo valor econômico com o tempo. Na Amazônia fluvial esse padrão de substituição das espécies não foi observado. Conclui-se que a diminuição da biomassa capturada ao longo do tempo somada à substituição de determinadas espécies de peixes capturados na costa da Mata Atlântica, podem indicar que a pesca não está sendo sustentável. Medidas preventivas de manejo pesqueiro devem ser implementadas. / Fisheries resources are being over-exploited worldwide. Excessive fishing can lead to trophic cascades and this exploration may be unsustainable. Therefore, management policies are urgent, but data are lacking to support such policies. In this sense, studies addressing interviews with fishermen have collaborated with the knowledge about the dynamics of fishing. The Brazilian artisanal fishing is the main economic and subsistence activity and the main source of protein for riverine Amazonian Caboclo populations and caiçara populations, who live in the coastal area of the Atlantic Forest. This study examined spatial and temporal ecological patterns in Brazilian artisanal fisheries in two ecosystems: the southeast coast of the Atlantic Forest and the fluvial Amazon; the data was based in interviews with fishermen on the course of several research projects. In Chapter 1 it was analyzed the fishery productivity in the southeastern coast. It was checked the variation in the average biomass of fish captured according to the interviews with fishers, due to temporal factors (fishermen’s age and date of their last fishery) and spatial factors (the region where the community of fishermen interviewed is located). There were analyzed interviews with 423 fishers, indicating that: a) there was a decrease in the biomass of fish caught over time, b) the biomass of fish caught was not influenced by the spatial factor c) there was no influence of age of the fisherman on the biomass of fish caught that was mentioned by them. Chapter 2 addressed the southeast coast of the Atlantic Forest and the Inland freshwater Amazon. It was analyzed the composition of fish caught, through their popular names mentioned by fishers and their mean trophic level. There were analyzed interviews with 658 fishers in the Amazon Basin (from 1987 to 2006) and with 821 fishers in to the southeast coast of the Atlantic Forest (from 1986 to 2009) (n = 1479 fishers). There was no variation in trophic level according to the time since the last fishing trip, and according to the spatial factors (ecosystem and region), and the region was the factor that most influenced the variation in trophic level. On the southeast coast of the Atlantic Forest species with similar trophic levels have been probably replaced by species of similar economic value over time. However, in the freshwater Amazon this pattern of species replacement was not observed. It is concluded that the decrease in biomass captured over time and the replacement of species on the Atlantic coast, may indicate that the fishery has been not sustainable. Preventive fisheries management measures should thus be devised.
73

Economie écologique des ressources marines : Le cas de la pêcherie crevettière guyanaise / Ecological economics of marine resources : The case of the french guiana shrimp fishery

Diop, Bassirou Masseck 02 December 2016 (has links)
L'objectif de cette thèse a été de comprendre le fonctionnement économique des pêcheries et de proposer des politiques de gestion des ressources halieutiques. L'attention a été portée essentiellement sur la pêcherie crevettière guyanaise. Une première analyse a été effectuée à partir d'une base de données historique. Les premiers constats ont été que cette pêcherie a été marquée par une forte diminution de son stock, de son effort, de sa production, ce qui a conduit à la fermeture de certaines entreprises. Les premiers résultats ont permis de comprendre que la production de cette pêcherie est fortement dépendante du stock et que la forte diminution de ce dernier n'est pas liée à la surpêche. En effet, malgré une baisse considérable de l'effort de pêche et du prélèvement, le stock a continué de s'effondrer, suggérant ainsi que d'autres facteurs peuvent être mis en cause. En particulier, la zone de pêche est caractérisée par un environnement amazonien avec une mangrove importante et de nombreux cours d'eau. L'intégration de la mangrove dans l'analyse, qui a pourtant connu une diminution de sa surface dans les années 90, n'a pas permis d'expliquer l'effondrement du stock observé. Cependant l'intégration d'autres facteurs comme le débit des fleuves et la température de surface de l'océan ont permis de mieux comprendre la chute du stock dans cette filière. La pêcherie crevettière guyanaise semble en effet fortement impactée par le changement global, notamment l'augmentation de la température des eaux dans les zones de prélèvement. De surcroît, le dernier chapitre suggère que certains phénomènes endogènes à la pêcherie, comme les effets de congestion entre les navires de pêche, rendent l'ensemble de la pêcherie plus sensible à des chocs exogènes technologiques, économiques ou biologiques, en amplifiant l'impact de ces derniers sur les décisions optimales des entreprises concernant l'effort de pêche. Afin de préserver la pêcherie crevettière en Guyane française, il apparaît donc essentiel d'essayer de limiter, dans la mesure du possible, les sources du changement climatique, au lieu de modifier profondément les pratiques économiques du secteur. / The objective of this thesis was to understand the economic behavior of fisheries and to propose resource management policies. The focus was mainly on the French Guiana shrimp fishery. First an initial analysis will be performed on a historical data basis. Initial findings have showed that this fishery was characterized by a strong decrease in its stock, its effort, its production and lead to the closure of some companies. The results have helped also to understand that the production in this fishery is highly dependent on stock and the decrease of the stock is not related to overfishing. Indeed, despite a considerable decline in fishing effort and production, the stock continued to slump suggesting that other factors may be involved. In particular the fishing zone is characterized by an Amazonian environment with significant mangrove and many rivers. The integration of mangrove in the analysis, which shows a decrease in its surface in the 90s did not explain the collapse of the stock. However, the integration of other factors such as rivers and sea surface temperatures have increased understanding of stock depletion in this sector. The French Guiana shrimp fishery is highly influenced by global change, notably increasing in temperature. Moreover, the last chapter suggests that some endogenous phenomena in the fishery, like the congestion effects between fishing vessels, make the whole fishery more sensitive to technology, exogenous economic or biological shocks, amplifying their impact on the optimal business decisions regarding fishing effort. In order to save the French Guiana shrimp fishery, it appears therefore crucial to try to limit the sources of climate change instead of deeply modifying economic practices in this sector, which may lead to misunderstandings by fishermen and local political conflicts.
74

A Historical and Analytical Description of the South Florida Recreational Tournament Fishery for Broadbill Swordfish, Xiphias gladius

Brewer, Elaine J. 01 April 2011 (has links)
Swordfish (Xiphias gladius) are increasingly sought after by recreational anglers around the world. The Florida Straits in particular are an important breeding and nursery area for North Atlantic swordfish, as well as for being historical fishing grounds for both recreational and commercial swordfish fisheries. The recreational fishery for swordfish in southeastern Florida is categorized into two historical periods. The first period started in 1977 and consists of the first tournaments in the area to specifically target swordfish. Despite high initial catches, low catch numbers forced the tournament fishery to close in 1983. During the second period of the fishery (starting in 2000 to today) the tournament fishery for swordfish has reemerged. Data from a total of 98 swordfish tournaments (17 historic, 81 current) have been collected. For comparison, information has been gathered from 72 istiophorid billfish tournaments within the modern (second) period. These data were gathered from tournament directors, websites, and personal communication with participants of the tournaments. The tournaments studied took place on the east coast of Florida from Stuart south to Key West, with a majority being held between Lighthouse Point and Islamorada in the Florida Keys. Although participation correlates to the number of catches, catch per hour (CPH) remains on a slow although not significant decrease over time. The entry fees for these modern period swordfish tournaments range from $200-600, while those for the more exclusive billfish tournaments are tenfold swordfish entry costs. Similarly, awarded prize monies of billfish tournaments are tenfold and significantly larger than prize monies for swordfish tournaments. The average weight of landed swordfish has shifted slightly in both the historic and the modern periods. Despite the oscillation of catch numbers throughout the two time periods, the weight of caught swordfish remained roughly the same. This may be from the minimum length restrictions implemented in the modern time period, a regulation which did not exist during the tournaments of the historic period.
75

Aspects of the ecology and management of the Soupfin shark (Galeorhinus galeus) in South Africa

McCord, Meaghen Erica January 2005 (has links)
Global trends in teleost fisheries indicate significant population declines. Thus, alternative fisheries are being developed to meet the growing economic and nutritional demands of the expanding human population. Recently, it has been established that elasmobranch fisheries may fulfill these demands. As many elasmobranchs possess life-history characteristics that make them particularly vulnerable to overfishing, it is imperative to develop management strategies prior to the inception of these fisheries to ensure sustainable resource utilisation. In South Africa, elasmobranchs have been commercially exploited since the 1930s. Although generally considered an under-exploited resource, the potential for growth within these fisheries has been recognized. In 2005, the commercial shark fishery will undergo a transition from medium to long-term rights allocations. This represents an ideal opportunity for scientists and managers to develop precautionary species-specific management plans for commercially exploitable elasmobranch species. The soupfin shark (Galeorhinus galeus) is one of the principal target species in South Africa’s shark fisheries. Given its inherent susceptibility to overexploitation, G. galeus was selected as a management priority by South Africa’s regional fisheries organisation. The purpose of this study was to examine and describe the stock status of G. galeus in South Africa, and to develop a precautionary fishery management plan to ensure the sustainability of this resource. Age, growth, and mortality calculations for G. galeus were made from research survey data collected between 1996 and 1999. A small sample size precluded independent analyses of females. The maximum recorded age for G. galeus was 33 years. Estimated von Bertalanffy growth parameters from observed length-at-age for males and combined sexes were: L∞ 1542.8 mm TL, K 0.21 year⁻¹ , t₀ -2.79 year⁻¹ and L∞ 1560.3 mm TL, K 0.19 year¹, t₀ -3.03 year⁻¹, respectively. The age-at-50% maturity was determined to be 6 years, corresponding to 1011 mm TL for males and 1100 mm TL for combined sexes. Natural mortality was calculated as 0.126 yr⁻¹. The rate of instantaneous total mortality was calculated as 0.27 yr⁻¹. Catch trend analysis showed that catches and CPUE of G. galeus are increasing in the demersal longline fishery, and decreasing in the handline fishery. Decreasing catches and CPUE were observed in fishery-independent research survey data. The status of the soupfin shark stock was modelled using per-recruit analysis. The SB/R model indicated the soupfin shark is being optimally exploited and spawner biomass is at 43% of preexploitation levels. Current fishing levels ( F = 0.14 yr⁻¹) approximate the Fsb₄₀ level (F = 0.17 yr¹); thus, an increase in fishing pressure may lead to stock collapse. It was determined that the current age-at-capture (7.9 years) should be increased to 10 years, or 1420 mm TL, to maximize yield and minimize the possibility of recruitment failure. The results of this study indicate a need for immediate scientific and management intervention in South Africa’s soupfin shark fishery. An assessment report and fishery management plan for G. galeus was compiled, and several management options were proposed. These include the implementation of licence and size restrictions, as well as seasonal/area closures. The potential for an experimental gillnet fishery should be investigated.
76

Caractéristiques biologiques spatialisées et influence des stratégies individuelles dans la gestion des ressources halieutiques : une approche par les jeux différentiels / Biological characteristics and spatial influence of individual strategies in the management of fishery resources : an approach based on differential games

Idda, Corinne 15 July 2014 (has links)
Une grande partie de la ressource halieutique est, à ce jour, surexploitée, voire menacée d’extinction. Il est donc nécessaire de gérer cette ressource de manière à assurer la viabilité du secteur économique de la pêche. L’objectif de ce travail est d’étendre et de compléter les modèles existant dans la littérature économique sur le sujet qui visent à analyser les effets de différentes stratégies de préservation de la ressource sur le profit du secteur de la pêche. Ces travaux souffrent en effet de deux limites principales.D’une part, ils mettent principalement en avant les caractéristiques biologiques de la ressource dans l’espace et leurs travaux se limitent généralement à la détermination du niveau de pêche qui assure le rendement soutenable maximal. Cependant, d’un point de vue économique, ces travaux sont limités puisqu’ils ne prennent pas en compte les interactions stratégiques entre agents.D’autre part, concernant les politiques de gestion de la ressource halieutique dans l’espace, peu de travaux intègre les stratégies individuelles des agents pour évaluer les impacts de ces règlementations sur l’état des stocks. De plus, en ce qui concerne les aires marines protégées, les travaux existant se concentrent sur les impacts de ce type de mesures sur les stocks de ressource et leur approche ne permet pas d’évaluer l’impact de la taille d’une aire marine protégée.Il est donc important d’élargir l’analyse dans deux directions. Tout d’abord, Nous allons tenter d’améliorer les travaux existants en y intégrant les stratégies des pêcheurs dans le cadre d’un secteur oligopolistique, (structure de marché représentative du secteur de la pêche), tout en prenant en compte les caractéristiques biologiques en termes de dispersion pour savoir dans quelle mesure ces différents aspects influencent les perspectives de préservation.Enfin, nous nous intéresserons, dans le même cadre d’analyse, aux politiques de gestion des ressources halieutiques pour évaluer leur efficacité. / Much of the fishery resource is, to date, overexploited even endangered. It is therefore necessary to manage this resource to ensure the sustainability of the fishery’s economic sector. The aim of this work is to extend and complete the existing models in the literature on the topic which aim for analyze the effects of different strategies for resource conservation benefit of the fishery sector. Indeed, these studies suffer from two main limitations.On the one hand, they put forward mainly the biological characteristics of the resource in space and their works are generally limited to the determination of the fishing level which provides the maximum sustainable yield. However, from an economic point of view, these works are limited, as they do not take into account the strategic behavior between agents.On the other hand, concerning the management policies of fishery resources in space, a few studies integrate agents’ individual strategies to evaluate the impacts of these regulations on the stocks state. In addition, with regard to marine protected areas, existing works focus on the impact of such measures on resources stock and their approach does not allow evaluating the impact of the size of a marine reserve.It is therefore important to extend the analysis in two directions. Firstly, we will try to improve existing works on integrating fishermen strategies in an oligopolistic sector (market structure representing the fishery sector), while taking into account the biological characteristics in terms of dispersion, to investigate in which extent these aspects influence the preservation prospects.Then, we focus, in the same analytical framework, the fishery resources management policies to evaluate their effectiveness.
77

Experimental Test of Genetic Rescue in Isolated Populations of Brook Trout

Robinson, Zachary L 17 July 2015 (has links)
Translocations are an important aspect of the management of natural populations in an increasingly fragmented landscape. Maintaining connectivity and gene flow is beneficial for both contemporary fitness and adaptive potential in the face of environmental change. Genetic rescue (GR) can alleviate inbreeding depression, genetic load, and increase adaptive potential of populations. Here, I have translocated 10 (5 of each sex) brook trout (Salvelinus fontinalis) to four geographically proximate and environmentally similar fragmented stream-dwelling populations of brook trout in Virginia to test for genetic rescue. The translocated brook trout contributed to more families than would be expected under neutral introgression, and hybridization resulted consistently in larger full-sibling family sizes. In the cohort immediately following translocation I observed relatively high (>20%) introgression in 3 of the 4 recipient sites, and in one recipient population 57.7 % of the offspring had at least one migrant parent. During the post-translocation period favorable regional climatic conditions resulted in large cohorts across recipient sites and controls, however the percent increase in juvenile abundance scales to initial genetic diversity and patch size. I observe strong evidence of hybrid vigor through consistently larger body sizes of hybrid offspring. At this point I cannot rule out potential negative effects of translocations such as outbreeding depression with out sampling more cohorts following genetic recombination. However, I provide an empirical and replicated foundation to begin assessing the efficacy of GR-motivated translocations for headwater fish conservation, and make a substantial contribution to the growing body of GR-literature.
78

An ecological approach to management of an important reservoir fishery

Kallis, Jahn L. January 2013 (has links)
No description available.
79

Population Genetic Analysis of Atlantic Horseshoe Crabs (Limulus polyphemus) in Coastal Massachusetts.

Johnson, Katherine T 23 March 2016 (has links) (PDF)
Atlantic horseshoe crabs (Limulus polyphemus) have endured decades of intense harvest pressure. Genetics studies have shown evidence of distinct sub-groups spanning the coast, although few fine-scale studies have been done to delineate these groups on a local level. Massachusetts lies directly between two of these sub-groups. With documented differences in prosomal widths of horseshoe crabs from either side of Cape Cod, it is possible that Cape Cod is a barrier to gene flow and that there are two distinct genetic groups within Massachusetts. Regulations currently consider all horseshoe crabs to be of one stock. I examined 6 microsatellite loci from 193 horseshoe crabs collected from 7 locations across Massachusetts between 5 May and 24 June 2010. I also analyzed the prosomal widths of 324 horseshoe crabs from 8 locations across Massachusetts. Data analysis revealed low divergence with a G′ST of 0.005 (95% CI −0.004–0.013) and a G″ST of 0.015 (95% CI −0.014–0.045). Wellfleet Bay showed evidence of divergence from all other sites except Buzzards Bay. Isolation by distance is apparent via the Atlantic Ocean. Phenotypic variation in the prosomal widths of horseshoe crabs shows greater divergence among sites than neutral markers and indicates the presence of additive genetic effects. Low divergence and high heterozygosity indicate that although documented population declines have occurred, effective population size (Ne) is still large enough to maintain allele frequencies. With isolation by distance, divergence is likely to increase over time if populations remain low. Phenotypic divergence shows the possibility of local adaptation and that the implementation of management units (MUs) to the north and south of Cape Cod would be recommended as a conservative measure.
80

Bycatch associated with a horseshoe crab (Limulus polyphemus) trawl survey: identifying species composition and distribution

Graham, Larissa Joy 04 September 2007 (has links)
Horseshoe crabs (Limulus polyphemus) have been harvested along the east coast of the United States since the 1800s, however a Fishery Management Plan (FMP) was only recently created for this species. To date, there have not been any studies that have attempted to identify or quantify bycatch in the horseshoe crab trawl fishery. A horseshoe crab trawl survey was started in 2001 to collect data on the relative abundance, distribution, and population demographics of horseshoe crabs along the Atlantic coast of the United States. In the present study, species composition data were collected at sites sampled by the horseshoe crab trawl survey in 2005 and 2006. Seventy-six different taxa were identified as potential bycatch in the horseshoe crab trawl fishery. Non-metric multidimensional scaling (NMS) was used to cluster sites and identify the spatial distribution of taxa. Sites strongly clustered into distinct groups, suggesting that species composition changes spatially and seasonally. Species composition shifted between northern and southern sites. Location and bottom water temperature explain most of the variation in species composition. These results provide a list of species that are susceptible to this specific trawl gear and describe their distribution during fall months throughout the study area. Identifying these species and describing their distribution is a first step to understanding the ecosystem-level effects of the horseshoe crab trawl fishery. / Master of Science

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