Canadian fisheries are in crisis. On both the Pacific and Atlantic coasts, stories abound of fisheries closures or failures and coastal communities in difficulty. A new approach to fisheries policy is required, one which recognises the intrinsic value of all participants in the fisheries ecosystem and is capable of providing guidance on how to make policy decisions. The principles of environmental ethics provide a framework for developing justice-based fisheries policies. The environmental ethics literature is first explored, with special attention to fisheries issues. From this review, a justice-based framework is identified, in which five types of justice are viewed as pertinent to fisheries concerns. This framework is then translated into an assessment tool, based upon the Rapfish method for rapid appraisal of fisheries and using a set of justice-based ethical criteria. These criteria are evaluated and, through a paired comparison survey, further explored. An assessment of a range of Canadian marine fisheries is conducted using these ethical criteria. Subsequently, a modified Rapfish assessment, using the original criteria supplemented with additional customised criteria, is conducted for Aboriginal fisheries for Pacific salmon in British Columbia. Additionally, a study is conducted which explores preferences regarding the abundance and diversity of fisheries ecosystems. Finally, the commercial fishery for Pacific salmon in British Columbia is presented as a case study. The Rapfish assessment results are presented, and considerations as to how to operationalise just policies for this fishery are suggested. Recommendations include: balancing the composition of the commercial fleet, based upon ecological impacts of the various gear types; encouragement of local stewardship and community involvement; and inclusion of various forms of knowledge in fisheries management and decision-making. / Science, Faculty of / Resources, Environment and Sustainability (IRES), Institute for / Graduate

An overview of stock-recruitment dynamics for major B.C. salmon (Oncorhynchus spp.) stocks is presented. Stock-recruitment patterns range from linear relationships to "Ricker" type relationships to no relationship at all. However, stocks for which there are accurate escapement estimates generally show patterns expected from stock-recruitment theory. It is concluded that errors in stock definition, mixed catch allocation, and spawning counts bias optimum escapement estimates downward so that poorly monitored stocks may become severely overexploited without being noticed. Because of poor escapement counts and/or difficulties in separating mixed catches, optimum escapements for many B.C. salmon stocks, which account for about half of the total B.C. production, cannot be estimated. Most stocks for which optimum escapement can be estimated are now being severely depleted. Restoration of these stocks by increasing escapement to optimum levels would increase the total catch by at least 40% of the current yield. Further, experimental management by increasing escapement appears to be the best policy for most of the other stocks. / Science, Faculty of / Zoology, Department of / Graduate

O curimbatá (Prochilodus lineatus) é uma espécie de importância comercial na pesca continental brasileira, especialmente na região da bacia do Rio Grande. Diversos estudos foram realizados com o curimbatá nesta região, incluindo os de delimitação populacional. Desde então, a região passou por alterações ambientais causadas pela construção de diversas barragens, impossibilitando migrações a montante, essenciais para a reprodução de P. lineatus. O presente estudo teve como objetivo verificar o impacto das barragens, sob o ponto de vista genético, na população de curimbatá da bacia do Rio Grande. Para tanto, foi utilizada a técnica de PCR-RFLP do fragmento entre os genes ND2 e CO1 e também da região controle, ambos do mtDNA, com 10 e 15 enzimas de restrição, respectivamente. Foram realizadas coletas em nove localidades entre barragens que não possuíam escadas para a migração de peixes. As localidades são: no Rio Grande - Cardoso, Colômbia, Conceição das Alagoas, Igarapava, Pedregulho e São João Batista do Glória; no Rio Mogi-Guaçu - Pirassununga e Espírito Santo do Pinhal; e no Rio Pardo - Jaborandi. Os resultados obtidos na análise do fragmento ND2-CO1 com três amostras, sendo uma de cada rio, não evidenciaram divergência significativa. Os índices de diversidade genética (haplotípica e nucleotídica) observados foram baixos, quando comparados com outras espécies de peixes. Estes resultados são condizentes com o esperado para seqüências conservadas, por isso, optou-se pela análise de uma região mais variável, como a região controle do mtDNA. Os resultados obtidos para a região controle (Fst, distribuição de Monte Carlo, teste exato e AMOVA) evidenciaram divergência significativa entre a amostra de Jaborandi e as demais, este fato pode ser devido a uma sub-estruturação populacional, ou a um erro de identificação da localidade de coleta. As outras amostras evidenciaram que, em geral, fazem parte de uma única população sob o ponto de vista genético. Não foi observada estruturação por distância, já que não houve correlação entre a distância genética e a distância geográfica. Os índices de diversidade (nucleotídica e haplotípica) são considerados de altos a moderados, sendo que os maiores foram obtidos para as amostras localizadas em trechos onde ainda há características naturais da bacia. A presença de poucos haplótipos amplamente distribuídos e internos na rede de haplótipos e de diversos haplótipos raros localizados perifericamente na rede, são um indício de expansão populacional recente. A expansão foi averiguada, também, com testes de neutralidade e gráficos de distribuição mismatch. O tempo de expansão foi calculado em 238 mil anos, que corresponde ao Pleistoceno Médio, época de grandes mudanças climáticas na América do Sul. Em conclusão, as alterações ambientais provocadas pelas barragens não geraram, a curto prazo, diferenças significativas entre as amostras estudadas, assim como parecem não estar diminuindo a variabilidade genética do curimbatá, quando comparada com a de populações naturais de outros rios. A divergência obtida para Jaborandi deve ser melhor estudada, mas parece refletir ausência de fluxo anterior à construção das barragens. O objetivo pretendido é o de apresentar um parâmetro de comparação para estudos futuros, especialmente aqueles que enfoquem o monitoramento da variabilidade genética do curimbatá. Estudos de longo prazo devem ser realizados no intuito de auxiliar o manejo pesqueiro do curimbatá, inclusive em programas de repovoamento. / Prochilodus lineatus has a commercial importance in the Brazilian freshwater fishing, especially in the Rio Grande basin. Several studies have been done with P. lineatus in this area, including those delimiting populations. Since then, the Rio Grande basin has been changed due to environmental impacts caused by construction of several dams. The most expressive impact for this population of P. lineatus was the impossibility of upstream migration, essential for its reproduction. The present study aimed at genetically verifying the impact of dams in the population of P. lineatus from Rio Grande basin. The PCR-RFLP method was used in mitochondrial DNA fragments ND2-CO1 and control region, with 10 and 15 restriction enzymes, respectively. Nine samples colected between dams with no fish ladders were analyzed: in Rio Grande - Cardoso, Colômbia, Conceição das Alagoas, Igarapava, Pedregulho e São João Batista do Glória; in Rio Mogi-Guaçu - Pirassununga e Espírito Santo do Pinhal; and in Rio Pardo – Jaborandi. Analysis results of the ND2-CO1 fragment with three samples, one from each river, did not show significant divergence. Values of haplotype and nucleotide diversity were low when compared to other fish species. These results are expected for conserved sequences, so analysis of a more variable region, such as the control region, was chosen. Results of the control region (Fst, Monte Carlo distribution, exact test and AMOVA) showed a significant divergence between Jaborandi sample and the others. This could be due to a population structure, or to an error in the locality identification. The other samples seem to be part of a single population. Isolation by distance was not verified since there is no correlation between genetic and geographic distances. Values of haplotype and nucleotide diversity ranged from high to moderate, with the highest values found in samples from localities where natural features of the basin still exist. Presence of few and widely distributed haplotypes internally in the haplotype net, and the occurrence of several other rare haplotypes distributed peripherically in the haplotype net, are typical of a recent population expansion. The expansion was also verified in neutrality tests and mismatch distribution. The calculated expansion time is 238 thousands of years that correspond to the Median Pleistocene, a period of great climatic changes in South America. In conclusion, the environmental changes caused by dams did not generate significant differences among the analyzed samples, in a short-term, and did not seem to be decreasing the genetic variability of P. lineatus, when compared to other natural populations. Divergence obtained for Jaborandi should be better studied, but seems to reflect the absence of gene flow prior to the construction of dams. These work intents to present a comparative parameter for future studies, especially those monitoring the genetic variability of P. lineatus. Longterm studies must be conducted to help fisheries management of P. lineatus, including restock programs.

The seeming lack of barriers to gene flow in the northwest Atlantic ocean has led to the general assumption that the population of the American lobster (Homarus americanus) is largely panmictic. However, morphological and genetic data presented in this dissertation suggest that lobster populations are less homogenous than once believed with potential for behavioral barriers to mating and selection of locally adaptive traits. Additionally, both long-term fishing pressures and the recent spread of a destructive epizootic shell disease may have impacted population structure. We developed a novel photographic technique to rapidly collect accurate morphological data with the ability to maintain a database of images for the purposes of re-sampling and testing additional hypotheses. During this study, we found significant morphometric differences between samples of lobsters from collection sites as close as 25km apart. Morphological differences may have originated due to differential selection or plastic responses to environmental variation. To analyze population genetic structure, I surveyed genetic variation using RADseq. Analysis of 1614 putatively neutral SNPs found little genetic difference (Average F¬ST=0.00137) between sample sites suggesting a high level of gene flow between regions. Several additional markers appeared to be under divergent selection between sample sites. A genome scan analysis of both neutral SNPs and SNPs under selection found several selected SNPs associated with principal components of morphological characters. A subsequent BLAST analysis identified a number of the selected SNPs lying in the H. americanus transcriptome, suggesting functional importance. Further experimentation is required to quantify the impacts of plasticity or local adaption in the origin of morphological differences between lobster populations, although the significant differences identified in this research are likely due to a combination of the two. The overarching conclusion is that lobster populations are, in fact, more differentiated than previously predicted and, as such, the findings presented here may have significant management implications.

Benthic animals have been widely used as health indicators of the marine benthic ecosystems in temperate regions. My PhD thesis mainly aimed to understand the responses of benthic ecosystem in tropical Hong Kong waters to the two management measures - pollution control and trawling ban. My study was based on sediment grab samples collected from 28 stations in three territory-wide surveys conducted in 2001, 2012 and 2015 in Hong Kong waters. I compared the spatial and temporal changes in macrobenthic community structure as well as physical and chemical characteristics of benthic habitats between surveys conducted before and after the pollution control measures in 2001 and 2012, as well as surveys before and after the fishery management measure in 2012 and 2015. The impacts of sewage pollution to benthic ecosystems had been noted in many studies, which included deteriorated water quality and bottom sediment, and disturbed, less diverse macrobenthic community dominated by opportunistic small-sized species. Therefore, sewage treatment and cessation of sewage effluent discharge were expected to lead to notable improvement in benthic habitats, biodiversity and macrobenthic communities; besides, responses of benthic ecosystems to pollution control may be hydrologically varied. In Hong Kong, a series of sewage treatment schemes, e.g. Stage 1 of Harbour Area Treatment Scheme (HATS), Tolo Harbour Action Plan (THAP), Tolo Harbour Effluent Export Scheme (THEES) and a number of sewage treatment works had been conducted in different areas of Hong Kong. Changes in the community structure were noted in the three focal areas with pollution control measures, i.e. Victoria Harbour, Deep Bay and Tolo Harbour; while apparent recoveries were noted inside the Victoria Harbour, the changes in benthic communities inside the Tolo Harbour and Deep Bay could not be attributed to the pollution control measures. Specifically, a decline in nutrient input to the eastern part of Victoria Harbour due to the implementation of HATS might have led to declined sedimentary total organic matter and the disappearance of the opportunistic species, and hence a recovery of benthic ecosystem therein. But in the sheltered Tolo Harbour and Deep Bay, neither improvement in sediment quality nor biodiversity were noted, thus indicating a longer duration is needed for the recovery of benthic ecosystems to take place in these land-locked bays. Degraded marine fishery resources and destruction in marine ecosystems had been noted since the introduction of modern trawling vessels had into Hong Kong since the 1950s and 1960s. Currently, most reports of benthic ecosystem responses to cessation of trawling originate from temperate regions, while it is not well understood for the situation in tropical areas. The territory-wide trawling ban in tropical Hong Kong waters was implemented by the Hong Kong government since December 31, 2012. Although improvement in benthic ecosystems was anticipated after the ban, it was unknown when this would happen and how different parts of the Hong Kong waters would respond to the trawling ban. My study showed that, around 3 years after the trawling ban, sedimentary organic matter content had increased significantly, and bottom water suspended solid loads had decreased in most of the survey stations, indicating territory-wide improvement in the benthic environment. Moreover, significant increases in richness, abundance and functional diversity of macrobenthos, as well as a more aggregated, fewer but larger station groups of macrobenthic communities were also detected after the trawling ban, indicating rapid recovery of the benthic communities. In conclusion, my study indicates that benthic communities in tropical Hong Kong can be used as bioindicators of environmental changes. Due to their restricted mobility, benthic organisms should be an integral part of the ecosystem monitoring aiming to detect the consequences of management measures to the marine environment. Environmental data including habitat complexity and hydrology are also required to fully understand the spatial and temporal dynamics of benthic ecosystems. Besides, my study has provided two territory-wide baseline data on the biodiversity and macrobenthic community structure in the tropical Hong Kong waters, which will be valuable for detecting future changes in the benthic ecosystems. My benthic ecology studies have resulted in a published paper and a manuscript ready for submission for publication. Besides focusing on benthic ecology, I have conducted taxonomic studies on benthic polychaetes, resulting in two published papers. As good taxonomy is the basis of high-quality data in benthic ecology, the training I received from studying these benthic polychaetes has enhanced my understanding of the biology of benthos, which is also important for my career development. However, since these papers do not fall into the main theme of my thesis, they are included in the thesis as appendixes only.

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In recent years, the blue crab fishery has become the main source of income for Virginia's watermen. This fact, along with growing concerns of overharvesting and uncertainty about the amount of effort in the fishery, has led to calls for more complete data on the fishery. This study examined the characteristics of Virginia's blue crab fishery, through an extensive survey of crab pot license holders conducted on a monthly basis from March to November of 1992. Along with a description of the people in the fishery, this study also modeled prices, harvest levels, and income levels for the blue crab industry. Because the models were interactive in nature, the effects of various fishery management strategies were also analyzed. The main emphasis of the policy simulations was to discover what impacts the different strategies had on harvest and income levels. The results of the simulations showed that many of the policies currently under consideration will have only a small impact on overall harvest and income levels, but there are some larger distributional effects among different firm classes. The findings of this study suggest that in order to gather accurate and useful data on the fishery, the random surveying techniques of this study should be continued over a period of years. / Master of Science

The largemouth bass (Micropterus salmoides) fishery was at an all time low on Lake Okeechobee when experimental supplemental stockings were done to try and enhance local bass populations. Largemouth bass had never been stocked on a large lake like Lake Okeechobee. The objectives were to develop a methodology, study dispersal, and compare stocked versus wild bass habitat choices. The methodology underwent considerable changes between studies. Bass dispersed to the edges by the second sampling period, so a larger sampling area may be needed. Water depth and pH were found to be significantly different between wild and stocked bass. Hatchery bass are naèive about predators, which may have resulted in stocked bass not moving to shallower areas like wild bass. The pH was weakly correlated with depth, so differences may be partially due to the fact that as depth increases, pH may also increase. / by Alyssa Jordan. / Thesis (M.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2012. Mode of access: World Wide Web.

Tuna are of significant global economic importance and a prime food source. Increased levels of fishing have resulted in many stocks being under threat and a number of species are considered to be overfished. The South African tuna industry has had limited management attention from the South African fisheries management agency. A recent development has been an increase in the number of tuna caught by small vessels that target the fresh tuna market in South Africa and overseas. This has highlighted the importance of developing a holistic management plan for the sector and creating an awareness, among vessel owners, of the importance of compliance with initiatives such as the Marine Stewardship Council (MSC). The South African tuna fishery comprises three sectors: baitboat, sport and longline, all of which are currently in need of acquiring more biological and fisheries data. This project was initiated to collate existing information and to collect additional information where possible. This encompassed a qualitative and quantitative assessment of the size and shape of the tuna fishing industry, which included estimates of total catch, effort, catch-per-unit-of-effort (CPUE) and stock structure (obtained through comparative estimates of age and growth), as well as socio-economic and economic information. A technique involving an examination of specific vertebrae was used to obtain age-growth information for T. albacares. These data were used to estimate von Bertalanffy (VBGF) growth parameters: F 2 1. , k 0.1 , and t₀ -0. 1 year. No significant differences in growth parameters were found in yellowfin tuna (Thunnus albacares) from different localities around the South African coast, i.e. from the south eastern Atlantic and the south western Indian Ocean. In addition, growth did not differ between South Africa and other regions (Draganic and Pelzcarski 1984, Fonteneau 1980, Gascuel et al. 1992, LeGuen and Sakagawa 1973, Lehodey and Leroy 1999, Lessa and Duarte-Neto 2004, Shuford et al. 2007, Stequert et al. 1996, Wild 1986, Yang et al. 1969). Further substantiation of the above-mentioned observations was found by recording differences in the sizes of fish caught in the inshore (baitboat and sport fishery vessels) and offshore (large pelagic longline vessels) sectors of South African tuna fisheries. A significant difference between the regions — in terms of the size of fish caught inshore — was noted, with mostly-juvenile fish being caught in KwaZulu-Natal (5.4 ± 3.5kg), sub-adult fish in the Eastern Cape (26.2 ± 13.4kg), and adult fish in the Western Cape (42.3 ± 14.4kg). Since mostly-adult fish were caught offshore by longliners, with no significant differences between regions, it is however possible th at adult fish predominantly inhabit the offshore region. Yellowfin tuna caught by the large pelagic longline fishery in the three managerial zones (A, B and C) were predominantly adult fish of similar size, namely Zone A: 38.9 ± 6.9kg; Zone B: 28.7 ± 4.6kg, and Zone C: 36.0 ± 5.1kg. The recreational ski boat sport fishery has remained stable, in terms of participation, consisting mostly of white middle aged males in the top 25% of household income distribution, having either permanent occupational status or being retired. Fishers within this sector are willing to incur great expense to partake in the fishery and they provide an important economic contribution to coastal towns, particularly in the Eastern Cape. The total catch (of 83t) of yellowfin tuna by the competitive sport fishery within the Western and Eastern Cape regions was considerably lower than that of commercial tuna baitboat catches, which amounted to 186t, and the large pelagic longline sector that caught t in 200. It is however likely that the competitive sport fishery's total yellowfin tuna catch (of 83t in 2009) of the Eastern and Western Cape competitive sport fishery was considerably less than the total yellowfin tuna catches of the whole South African deep-sea sport fishery. Longfin tuna are the primary target species of South Africa‘s baitboat fisheries, comprising an average of 86% of the total catch and generating ZAR49 million in employment income in 2002. South Africa was responsible for 20% of the total longfin tuna annual yield in 2004 in the southern Atlantic Ocean, behind Taiwan with 59%. However, yellowfin tuna only contributes a small percentage towards total catches (8.4 ± 8.2% between 1995 and 2009), generating ZAR1.3 million in employment income in 2002. Of the four vessel categories comprising the tuna baitboat fishery, ski boats had the highest yellowfin tuna CPUE in 2009 (117 ± 62 kg.vessel⁻¹.day⁻¹) and the lowest effort. The ski boats sector is the most opportunistic fishery as they are only active when either longfin or yellowfin tuna are in high abundance. At such times catches are guaranteed, so can be expected to offset expenses. In 2009 the CPUE for yellowfin tuna for 15–19m vessels and freezer deckboats was 12 ± 20kg.vessel⁻¹.day⁻¹ and 3 ± 6kg.vessel⁻¹.day⁻¹, respectively. These vessels specifically target longfin tuna when they are in abundance. Since the start of the tuna baitboat fishery in 1995, there has been a substantial increase in the number of new entrants. In 2002 this sector had a fleet size of 82 vessels with a capital value of ZAR163 million and a total employment income of ZAR58 million, employing 2 173 fishers, of which 87% were black African. The commercial tuna baitboat fleet has subsequently grown to 200 vessels and 3600 crew, with 110 active vessels fishing for a combined fleet average of 46 days per year. There are a high number of owner-operated vessels. Since 2007 the fishery's profit to cost ratio has been low due to the low abundance of tuna stocks off the coast of South Africa, which has resulted in poor catch returns, placing economic pressure on the fishery. The baitboat industry is a low-profit-margin fishery with a total net catch value worth ZAR90 million in 2009 (Feike 2010). The abundance of yellowfin tuna influences profit margins, with very high profits being made when abundance and catches are high. The large pelagic longline fishery has a total allowable effort of 43 vessels of which only 30 vessels fished during 2009, when a reported 766t of yellowfin tuna were caught, representing a total tonnage far in excess of that obtained by the combined effort of the baitboat and sport fishery. It is, however, assumed that considerable underreporting of catches takes place within this fishery, which means that the estimated total net catch value of ZAR100 million could, in fact, be much higher. Such underreporting of catches is of great concern for this fishery, as is the high bycatch of Chondricthians spp. that significantly outweighs imposed regulatory limits (DEAT 2007). The present study demonstrates the current lack of comprehensive catch and effort data for the sport, baitboat and longline fisheries as well as the serious limitations and flaws associated with current databases. Results from the present study have drawn attention to a number of high-priority research needs, as outlined below. (1) A major lack of comprehensive catch and effort data for the sport fishery, which can be rectified by focussing on obtaining more competition data, as well as high-quality catch and effort and socio-economic information, as opposed to relying on information from non-club anglers (Gartside et al. 1999, Williams 2003, Cass-Calay 2008). Acquisition of such data is relatively inexpensive: the location of organized clubs and their frequent competition meetings provide widespread coverage along the Southern African coastline. Such data acquisition efforts have the potential to provide reliable information on spatial catch trends. (2) Validation of vessel catch return data is required for commercial fisheries and on some recent data that has emerged from studies of catch rates and trends for target species, particularly in the longline fishery. In this context it should be noted that the most recent peer-reviewed publications on this exploratory fishery were published more than a decade ago (Kroese 1999, Penny and Griffiths 1999). Additional studies need to be undertaken and journal articles published on the current stock status of South African catches of yellowfin and bigeye tuna and swordfish.