The aim of this report was to establish what category the harbour porpoise is listed as on the Swedish national redlist as well as analyze what potential sub-criteria the species fulfills besides criteria already established. The aim was also to evaluate the willingness to pay for conservation of the harbour porpoise for the first time and make a comparison of the willingness to pay between geographic places where the harbour porpoise is currently existing and where it is not. The subpopulation of the harbour porpoise in Skagerrak-Kattegat is listed as vulnerable (VU) on the national redlist and the subpopulation in the Baltic sea is listed as critically endangered (CR). Actions and precautions which have been made for conservation and protection of the harbour porpoises in Swedish waters are new Swedish laws and law proposals as well as formations of organizations such as ASCOBANS and further research. The results from the survey showed that the mean of the single time payment sum those questioned were prepared to pay to retain the porpoises at a stable population level was 273 SEK. Geographically the study showed no significant difference in geographic position and where the harbour porpoise exists but showed that the inhabitants of the south-east coast were willing to pay about half the sum, 165 SEK, of the mean sum that the north-east coast were willing to pay, 335 SEK. The results regarding the populations’ conjecture of historical threats and threats nowadays showed a significant difference from reality. Overfishing of prey had the highest amount of answers as a threat both historically and nowadays. Bycatch, which is accepted as todays biggest threat by researchers and organizations, came third place in the results from the survey study with a percentage of 14.5 %.

Pteroplatytrygon violacea is the only member of the Dasyatidae family that exhibits an entirely pelagic behavior. Age, growth and reproduction characteristics were estimated for western north Atlantic populations, where it is a common bycatch species of commercial pelagic longline fisheries targeting swordfish and tuna. Ages were assigned by counting band-pair deposition on vertebral centra sections. An annual pattern of band-pair deposition was validated through marginal increment analyses. Age estimates ranged from 2.5 to 8 years for males and 3 to 10 years for females. The von Bertalanffy growth model, a modified form of the von Bertalanffy, a two-parameter form of the von Bertalanffy with a fixed length-at-birth, the Gompertz growth model and a logistic model were fitted to sex-specific observed size-at-age data. Models were fitted using maximum likelihood estimation and nonlinear least squares methods. Resulting models were evaluated based on biological rationale and Akaike’s information criteria. All growth models yielded similar estimates, however the two-parameter Von Bertalanffy growth model provided the best fit for both males (L∞ = 54.79 cm (Disc width, DW) and k = 0.44 year-1) and females (L∞ = 65.56 cm (DW) and k = 0.26 year-1). Reproduction was determined by assessing maturity and reproductive stages. Sexual dimorphism was observed where females grew significantly larger than males. Males were determined mature when DW was greater than 38cm when claspers were shown to be fully calcified and vas deferens were coiled. Females were determined to reach maturity between 40 and 50 cm DW although a lack of smaller sized females prevented a more accurate estimate of first maturity. Females were observed pupping near term embryos ranging from 14.2 to 16 cm DW in mid-July and late September indicating possibilities of two litters per year. Large oocytes where observed in an ovary in a female with a uterus containing seven eggs with a mean mass of 2.80 g indicating that P. violacea exhibit vitellogenesis proceeding simultaneously with gestation. A clear seasonality for the reproductive cycle was not apparent however it seems parturition occurs in late spring and early fall when conditions are optimal for neonate survival. Data on the age, growth and reproduction of western north Atlantic populations of P. violacea will contribute to the lack of life history characteristics of this common bycatch species.

Although closed seasons, bag limits and quotas are used to manage fishes within the Grouper/Snapper Complex off the southeastern United States, size limits are the cornerstone of fisheries management. Because fishers must release all undersized fishes despite fish condition, this regulation has created a mandatory catch and release system. Inherent in this management strategy is the supposition that these undersized fish survive in sufficient numbers so as to justify this regulation. To satisfy this criteria fish mortality must be low and released fish must also experience minimal sub-lethal effects. Determination of sublethal effects and evaluation of their potential impairment and duration of injury are required to develop effective physiology-based criteria to evaluate the efficacy of the minimum size rule. The goal of this research was to evaluate some aspects of the efficacy of the minimum size rule in the red grouper and red snapper fisheries off Florida by collecting traditional fisheries data and analyzing it in light of fish physiology, ecomorphology and behavior. Study objectives included 1) determination of the causes for the differences of hook mortality for red grouper and red snapper in the recreational and recreational-for-hire fisheries by necropsy of acute and latent mortalities, analysis of tag and recapture data for both J and circle hooks, determination of fish dentition and any differences in feeding behavior, 2) examination of the effects of rapid depression from depth on fish survival by inspection and comparison of the red grouper and red snapper swim bladders in both healthy and swim bladder ruptured fish from various water depths, comparison of tag and recapture data, investigation of the effects of fish venting, and laboratory simulations using fish hyperbaric chambers to determine healing and survival from rapid depression trauma, 3) analysis of movement patterns of tagged fish and 4) evaluation of some of the consequences imposed by the minimum size limit based on study results.

The development and adaptation of gear technologies to local fisheries has been a management-oriented research strategy commonly used to mitigate the ecological effects of pelagic longline (PLL) gear on bycatch species. Grenada’s PLL fishery primarily targets yellowfin tuna, however while minimal, their bycatch of blue marlin and white marlin exceeds the Total Allowable Catch (TAC) allowed by the International Commission for the Conservation of Atlantic Tunas (ICCAT). A switch to circle hooks may benefit these nontargeted, bycatch species by reducing catch rates and haulback mortality, as well as increasing post-release survival. To determine differences in performance, assessments of 16/0 circle hooks and 9/0 J hooks were alternated over 26 sets between January and June 2018. Catch, mortality, hook location, length and grade of fish were compared between hook types. No differences in haulback mortality rate for all species, or yellowfin tuna grade were found between hook types. However, significantly fewer billfish collectively (t= 2.36, p= 0.028), and sailfish specifically (t= 3.04, p=0.005), were caught on circle hooks. Additionally, tuna caught with circle hooks had a 69% greater chance of external hooking compared to J hooks (X2 = 4.38 p=0.036). All other species analyzed had statistically similar catch rates regardless of hook type (p < 0.05), including, yellowfin tuna. The results of this study indicate the Grenadian PLL can reduce its impact on billfish bycatch by using 16/0 circle hooks without incurring negative effects on their tuna catch rate or grade. This research provides further evidence that circle hooks should be the recommended gear type when using a bycatch mitigation approach to manage PLL fisheries.

No description available.

The U.S. pelagic longline fishery catches 98% of domestic swordfish landings but is also one of the three fisheries most affecting federally protected sea turtles (Crowder and Myers 2001, Witherington et al 2009). Bycatch by fisheries is considered the main anthropogenic threat to sea turtles (NRC 1990). Accurate and precise bycatch estimates are imperative for sea turtle conservation and appropriate fishery management. However, estimation is complicated by only 8% observer coverage of fishing and data that are hierarchical in structure (i.e., multiple sets per trip), zero-heavy (i.e., bycatch is rare), and often overdispersed (i.e., larger variance than expected). Therefore, I evaluated two predominant bycatch estimation methods, the delta-lognormal method and generalized linear models, and investigated improvements in uncertainty incorporation. I constructed a simulation model to evaluate bycatch estimation at two spatial scales under ten spatial models of sea turtle, fishing set, and observer distributions. Results indicated that distributing observers relative to fishing effort and using the delta-lognormal-strata method was most appropriate. The delta-lognormal-strata 95% confidence interval (CI) was wider than statistically appropriate. The delta-lognormal-all sets pooled 95% CI was narrower but simulated bycatch was above the CI too frequently. Thus, I developed a bycatch estimate risk distribution to incorporate uncertainty in bycatch estimates. It gives managers access to the entire distribution of bycatch estimates and their choice of any risk level. Results support the management agency's observer distribution and estimation method but suggest a new procedure to incorporate uncertainty. This study is also informative for many similar datasets. / Master of Science

The bycatch of cetaceans in fishing gear is considered to be one of the biggest conservation threats to these species. Gear modifications have the potential to reduce these bycatches in global fisheries but there is little available information on how such modifications may change the fishing performance of gear, or indeed the behavior of cetaceans interacting with fishing gear. Generalized linear models (GLMs) were used to identify factors related to cetacean bycatches in UK bottom set gillnets. Rigged net height had a significant positive relationship with harbour porpoise (Phocoena phocoena) bycatch in ICES Area VII suggesting that lowering the profile of gillnets may have the potential to reduce bycatch rates. Modifications to gillnets, such as changing the amount of floatation or increasing the density of the meshes, were found to have significant effects on the active fishing heights of these nets. However, results from a bycatch mitigation trial in Argentina showed that the reduced fishing profile of one experimental net did not result in a concurrent reduction in the bycatch rate of Franciscana dolphins (Pontoporia blainvillei). While there was no significant difference in the rate, length or intensity of harbour porpoise encounters in the presence or absence of gillnets, the proportion of fast echolocation click trains were significantly higher when a net was present, indicating that porpoises either increased acoustic inspection of the net or foraging in the vicinity of the net. An analysis of underwater video footage collected inside trawl nets in an Australia fishery showed that bottlenose dolphins (Tursiops sp.) were present inside nets more frequently than they were caught and were actively foraging inside these nets. The orientation of dolphins inside these nets indicates that the current design of excluder devices used in this fishery could be improved to further reduce bycatch rates.

In Lake Pontchartrain Basin, commercial fishing in estuarine habitats impacts many non-target species collected as bycatch. I investigated the bycatch assemblages collected by commercial vessels and compared these to assemblages collected by typical fishery-independent methods. I compared assemblages using analysis of similarity (ANOSIM) and determined important species by weight and abundance using similarity percentages analyses (SIMPER). I also examined differences in size-class distributions by gear type using density kernel plots and Mann-Whitney U tests. The two gear types collected significantly different assemblages (ANOSIM R = 0.522, p = 0.001) and gear type explained more composition differences than other factors such as month, daytime, or location. Fishery-independent gear underestimated the importance of many species. Although fishery-independent data are invaluable for monitoring assemblage dynamics, fishery-independent gear collects different assemblages than commercial gear. Larger fishes of important species were caught less often in bycatch, but completely absent from fishery-independent gear.

Orientador: Leandro Mantovani de Castro / Resumo: A Olivancillaria urceus é uma das espécies de gastrópode marinho mais abundante na região subtropical da costa sudeste brasileira, frequentemente capturada na pesca de arrasto de fundo do camarão sete barbas. Nos últimos anos, a investigação química em moluscos marinhos têm revelado informações sobre uma variedade de compostos de interesse clínico, em especial os peptídeos, apresentando propriedades farmacológicas distintas, como por exemplo, ação antimicrobiana. Neste contexto, o objetivo deste trabalho foi o isolamento e caracterização de peptídeos que existam naturalmente nos tecidos do gastrópode marinho Olivancillaria urceus utilizando-se de um método específico de extração, seguido de fracionamento por cromatografia líquida em coluna C18, ensaio de atividade antimicrobiana contra os microorganismos: M. luteus, E. coli e C. albicans, e identificação das frações com atividade por espectrometria de massas. Nossas análises identificaram uma fração do extrato peptídico, denominada 18-M-3, com atividade antimicrobiana contra a bactéria Micrococcus luteus, apresentando uma concentração média de 2,18 mg/ml. A análise por espectrometria revelou tratar-se de uma fração complexa, constituída principalmente por um conjunto de peptídeos descritos pela primeira vez, fragmentos de proteínas citosólicas e nucleares conservados em diferentes espécies de moluscos. Estes resultados abrem novas perspectivas sobre o potencial farmacológico de extratos O. urceus. / Abstract: Olivancillaria urceus is one of the most abundant marine gastropod species in the subtropical region of the Brazilian southeast coast, often caught in shrimp trawling. In recent years, chemical research in marine molluscs has revealed information on a variety of compounds of clinical interest, especially peptides, exhibiting distinct pharmacological properties, such as antimicrobial action. In this context, the aim of this work was the isolation and characterization of peptides that exist naturally in the tissues of the marine gastropod O. urceus using a specific extraction method, followed by liquid chromatography fractionation on C18 column, antimicrobial activity tests against microorganisms M. luteus, E. coli e C. albicans, and identification of the fractions with activity by mass spectrometry of. Our analyzes identified a fraction of the peptide extract, designated 18-M-3, with antimicrobial activity against the bacterium Micrococus luteus, presenting an average concentration of 2.18 mg / ml of peptides. Spectrometric analysis revealed a complex fraction consisting mainly of a set peptides, fragments of cytosolic and nuclear proteins conserved in different species of mollusks. These results open new perspectives about the pharmacological potential of O. urceus extracts. / Mestre

Submitted by (edna.saturno@ufrpe.br) on 2017-02-14T16:45:41Z No. of bitstreams: 1 Jose Carlos Pacheco dos Santos.pdf: 638792 bytes, checksum: 6f28321f4c3fd95cd1db01843c010e88 (MD5) / Made available in DSpace on 2017-02-14T16:45:41Z (GMT). No. of bitstreams: 1 Jose Carlos Pacheco dos Santos.pdf: 638792 bytes, checksum: 6f28321f4c3fd95cd1db01843c010e88 (MD5) Previous issue date: 2007-09-03 / Aiming compare the indices of catch per unit of effort, hook location, and the condition of the fishes caught in two different types of hook, the “circle” (18/0) and “J” (9/0), 81 pelagic longline sets in a equatorial area were observed. The indices of catches for the albacore (Thunnus alalunga), yellowfin tuna (Thunnus albacares) and swordfish (Xiphias gladius) had not presented a significant differences between the two the types of hook, whereas the bigeye tuna (Thunnus obesus) target specie in these fisheries, were significantly more caught in the circle hooks than in “J” hooks. The “circle” hooks also showed a mortality rate lesser than the “J” hooks, thus increasing the indices of non target species discarded alive, as for example the blue and white marlin, which in Brazil are being caught beyond the quotas stipulated by the ICCAT (International Commission for the Conservation of Atlantic Tunas). This fact brings a substantial quality improvement results during the disembark, resulting a high final products qualifying to export and consequently a best sale price. / No intuito de comparar o desempenho dos anzóis, o índice de captura por unidade de esforço, o posicionamento do anzol no corpo do animal capturado, e a condição do peixe no recolhimento, foram observados 81 lances de uma pescaria comercial com espinhel, operando no Atlântico sul equatorial, na qual os anzóis “circulares” (tamanho 18/0) e os anzóis do tipo “J” (tamanho 9/0) foram utilizados de forma alternada. As taxas de captura para albacora branca (Thunnus alalunga), albacora laje (Thunnus albacares) e o espadarte (Xiphias gladius) não apresentaram diferenças significativas entre os dois tipos de anzol, enquanto que a albacora bandolim (Thunnus obesus) principal alvo da pesca, foi significativamente mais capturada nos anzóis “circulares”, os quais apresentaram, também, uma taxa de mortalidade no momento do recolhimento muito menor, podendo assim aumentar a taxa de descarte vivo de animais que compõem a fauna acompanhante, como por exemplo os agulhões negro e branco, que no Brasil estão sendo capturados além das cotas estipuladas pela International Commission for the Conservation of Atlantic Tunas - ICCAT. Tal fato resulta em uma melhora substancial da qualidade do pescado na hora do desembarque, resultando, assim, em uma melhor qualificação do produto final para exportação e consequentemente um melhor preço de venda.