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Submitted by Chaylane Marques (chaylane.marques@ufpe.br) on 2015-03-11T18:50:46Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) tese_RASM_PGBA.pdf: 7593159 bytes, checksum: 760a0f5b5cd0b17f7618683e1b864ad9 (MD5) / Made available in DSpace on 2015-03-11T18:50:46Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) tese_RASM_PGBA.pdf: 7593159 bytes, checksum: 760a0f5b5cd0b17f7618683e1b864ad9 (MD5) Previous issue date: 2012-04-27 / A maior abundância de siris (Família Portunidae) no Canal de Santa Cruz/PE/ Brasil, ocorreu no período seco. Dentre as cinco espécies que ocorreram no Canal, Callinectes danae Smith, 1869 foi a mais abundante, sendo sua ocorrência influenciada pela altura da maré e pela salinidade. As fêmeas de C. danae realizaram cinco mudas no período bentônico, enquanto que os machos realizaram seis, sendo essas mudas influenciadas pela temperatura e salinidade. Quando mantida em cativeiro, essa espécie manteve o número de ecdises, porém, atingiu tamanhos menores. Ambos os sexos cresceram segundo o modelo de von Bertalanffy. Os machos atingiram tamanhos maiores e apresentaram uma longevidade menor que as fêmeas. Ao longo do crescimento, tanto os machos quanto as fêmeas apresentaram diferentes formas geométricas da região dorsal e ventral do cefalotórax, sendo a mais notória, a variação do formato do abdômen. O tamanho da largura do cefalotórax de primeira maturação dos machos foi de 8,99 cm e das fêmeas, de 7,16 cm. As fêmeas copularam uma única vez na vida, durante a muda puberal. Elas iniciaram o desenvolvimento gonadal de forma sincrônica à ecdise e apresentaram um ciclo reprodutivo sazonal, com pico entre novembro e dezembro. As fêmeas realizaram migração para regiões mais salinas do estuário, próximo ao mar, e realizaram desovas múltiplas vezes, apresentando uma alta fecundidade. Já os machos, após atingirem a maturidade das gônadas, puderam copular com diversas fêmeas e estiveram sempre prontos à cópula. Os indivíduos se deslocaram ao longo do canal para realizarem o ciclo reprodutivo, e as fêmeas adultas, após chegarem às águas mais salinas, não retornaram ao estuário. A mortalidade total dos machos foi maior do que das fêmeas, porém a taxa de exploração para ambos os sexos se encontrou dentro dos limites aceitáveis para a manutenção da população.

Thesis (M.S.)--University of North Carolina at Wilmington, 2006. / Includes bibliographical references (leaves: 40-42)

Thesis (Ph.D.)--Murdoch University, 2004. / Thesis submitted to the Division of Science and Engineering. Bibliography: leaves 199-219.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 129-131). Also available via the Internet.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 107-118). Also available via the Internet.

Este estudo teve como objetivo analisar a qualidade dos sedimentos do complexo estuarino de Cananéia-Iguape-Peruíbe (CIP), utilizando Biomarcadores, análises químicas e ecotoxicológicas, a fim de determinar se os metais nos sedimentos estariam biodisponíveis para os organismos bentônicos. As estações PT e PM apresentaram as piores condições, com toxicidade crônica (PT e PM) e aguda (PT), concentração de metais no sedimento e maior indução dos biomarcadores. As piores condições tendem a estar associadas aos sedimentos finos. Os elementos Pb, V, Co, Ni e ZN ultrapassaram os limites de \"Sediment Quality Guidelines\" (SQVs) nas estações PT e PM, Pb ultrapassou também os limites de TEL. A indução dos biomarcadores analisados e danos nos tecidos apresentaram maiores valores durante o inverno. As diferentes ferramentas utilizadas mostram que a contaminação por metais, advindas das atividades de mineração do Alto do Rio Ribeira de Iguape estão influenciando o estuário. A toxicidade encontrada foi atribuída principalmente aos metais, sugerindo que os fatores antrópicos produzem riscos ecológicos. Além disso, como a toxicidade durante o verão se apresenta mais na parte superior do estuário e no inverno essa mesma toxicidade se apresenta nas estações mais ao sul, esse estudo evidenciou que as áreas de deposição parecem mover-se ao longo do estuário, o que depende da quantidade da entrada de água doce no sistema, que se apresenta associada a sazonalidade. / This study aimed to analyze the sediment quality of the Cananéia-Iguape-Peruíbe estuarine complex (CIP) by using biomarkers, geochemical and ecotoxicological analyses, in order to determine if metals from sediments were bioavailable to benthic organisms to the point of causing negative effects. Stations PT and PM presented the worst conditions, with chronic (PT and PM) and acute toxicity (PT), metal contamination and biomarkers induction. Worst condition tend to be associated to fines. Elements Pb, V, Co, Ni and Zn exceeded Sediment Quality Guidelines (SQVs) limits for stations PT and PM, Pb exceeding also TEL values. Biomarkers induction and tissue damage appears to be worse during winter. The different lines of evidence showed that the metal contamination from mining activities on upper Ribeira de Iguape River alters the estuary. Toxicities were attributed mainly to metals suggesting that the anthropic factors are capable of producing ecological risks. Additionally, such as summer toxicity are present in the northern estuarine portion and during winter, this same toxicity appears to be in the southern portion, this study evidenced that depositional areas appears to move along the estuary, which in its turn depends on the freshwater inputs associate to seasonality.

Este estudo teve como objetivo analisar a qualidade dos sedimentos do complexo estuarino de Cananéia-Iguape-Peruíbe (CIP), utilizando Biomarcadores, análises químicas e ecotoxicológicas, a fim de determinar se os metais nos sedimentos estariam biodisponíveis para os organismos bentônicos. As estações PT e PM apresentaram as piores condições, com toxicidade crônica (PT e PM) e aguda (PT), concentração de metais no sedimento e maior indução dos biomarcadores. As piores condições tendem a estar associadas aos sedimentos finos. Os elementos Pb, V, Co, Ni e ZN ultrapassaram os limites de \"Sediment Quality Guidelines\" (SQVs) nas estações PT e PM, Pb ultrapassou também os limites de TEL. A indução dos biomarcadores analisados e danos nos tecidos apresentaram maiores valores durante o inverno. As diferentes ferramentas utilizadas mostram que a contaminação por metais, advindas das atividades de mineração do Alto do Rio Ribeira de Iguape estão influenciando o estuário. A toxicidade encontrada foi atribuída principalmente aos metais, sugerindo que os fatores antrópicos produzem riscos ecológicos. Além disso, como a toxicidade durante o verão se apresenta mais na parte superior do estuário e no inverno essa mesma toxicidade se apresenta nas estações mais ao sul, esse estudo evidenciou que as áreas de deposição parecem mover-se ao longo do estuário, o que depende da quantidade da entrada de água doce no sistema, que se apresenta associada a sazonalidade. / This study aimed to analyze the sediment quality of the Cananéia-Iguape-Peruíbe estuarine complex (CIP) by using biomarkers, geochemical and ecotoxicological analyses, in order to determine if metals from sediments were bioavailable to benthic organisms to the point of causing negative effects. Stations PT and PM presented the worst conditions, with chronic (PT and PM) and acute toxicity (PT), metal contamination and biomarkers induction. Worst condition tend to be associated to fines. Elements Pb, V, Co, Ni and Zn exceeded Sediment Quality Guidelines (SQVs) limits for stations PT and PM, Pb exceeding also TEL values. Biomarkers induction and tissue damage appears to be worse during winter. The different lines of evidence showed that the metal contamination from mining activities on upper Ribeira de Iguape River alters the estuary. Toxicities were attributed mainly to metals suggesting that the anthropic factors are capable of producing ecological risks. Additionally, such as summer toxicity are present in the northern estuarine portion and during winter, this same toxicity appears to be in the southern portion, this study evidenced that depositional areas appears to move along the estuary, which in its turn depends on the freshwater inputs associate to seasonality.

This dissertation investigated ingress of postlarval blue crabs Callinectes sapidus to the Newport River estuary, North Carolina, USA. Data from C. similis, Menippe mercenaria, Pachygrapsus transversus, and Arenaeus cribrarius are included in some chapters for comparison. Changes in tolerance to low salinity were examined by: 1) exposing postlarvae (megalopae) collected in coastal and estuarine areas to a range of salinities and 2) determining the cue that stimulates acclimation of coastal megalopae to low salinities, the time to acclimation, and the decrease in salinity necessary for acclimation. Coastal megalopae were less tolerant to salinities of 5 and 10 than megalopae from the estuary. Coastal megalopae became acclimated to low salinities within 12 h when salinity was reduced from 35 to 31. Spatial patterns in abundance during ingress were investigated simultaneously in coastal and estuarine areas. Coastal distributions were determined using nighttime surface plankton tows at slack water after ebb tide and slack water after flood tide on four nights; two each during spring and neap tides. Estuarine distributions were determined using nightly settlement on 'hog's hair' collectors. C. sapidus megalopae were most abundant at the coast east of Beaufort Inlet, but settlement was restricted to western channels of the estuary. Species-specific patterns in abundance were maintained during two spring/neap cycles, possibly due to interactions between larval behavior and physical forcing. Biophysical mechanisms of estuarine ingress were investigated by comparing nightly abundance in coastal and estuarine areas with environmental variables. Comparisons were made using cross-correlation and cross-fourier analyses. High estuarine abundances were associated with wind-driven estuarine inflow and nighttime flood tides. The seasonal pattern of estuarine ingress was strongly associated with the seasonal pattern of alongshore wind stress, suggesting that inter-annual variations in atmospheric forcing may determine the yearly abundance of megalopae arriving in estuarine nursery habitats. The effect of sampling interval on annual megalopal abundance estimates was determined using an 11-year dataset of nightly settlement. Variability in abundance estimates increased with increasing sampling interval. Switching from a one day to two day sampling interval resulted in a 20 % decrease in the likelihood of detecting a significant correlation between annual abundance and CPUE in the North Carolina blue crab pot fishery. / Dissertation

<p>This dissertation investigated spawning biology of female blue crabs, <italic>Callinectes sapidus</italic>. Females mate following the terminal molt and undertake a spawning migration seaward, producing multiple clutches of larvae. To examine lifetime reproductive potential of female crabs, individual crabs were confined in the field from terminal molt to death. Crabs produced up to 7 clutches over 1-2 spawning seasons and survived up to 394 d after the terminal molt. Time to first clutch and time between clutches were positively correlated with carapace width and best described by degree-days. Size at maturity was negatively correlated with water temperature on the day of the terminal molt. Most measurements of clutch quality and larval fitness were similar for all clutches. The percentage of embryos developing normally decreased 40% from clutch 1 to clutch 4 and clutch volume decreased 50% from clutch 1 to clutch 5. Thus, most of a crab's reproductive output is from the first few clutches. </p><p>Using swimming and abdominal pumping assays, the roles of pheromones in larval release and migratory behavior were investigated. Following delivery of egg extract, bradykinin (a pheromone mimic), and trypsin (an enzyme that generates peptide pheromones), ovigerous crabs responded with increased abdominal pumping, indicating that peptide pheromones stimulate larval release in blue crabs. Ovigerous crabs responded with increased swimming following delivery of egg extract, but not following delivery of a peptide pheromone mimic or an enzyme that produces peptide pheromones. These results suggest that some substance generated from the egg mass stimulates vertical swimming, but that peptides alone do not stimulate swimming. A blend of molecules, possibly including sugars, may be the cue that stimulates swimming behavior. </p><p>Endogenous rhythms in vertical swimming, a mechanism underlying migration in tidal estuaries, were examined in the laboratory under constant conditions in juvenile females, recently-molted females, and females with mature ovaries from Beaufort, NC. Rhythms were variable in each stage, though circatidal rhythms consistent with ebb tide transport were observed in juvenile females and recently-molted females. Crabs with mature ovaries typically swam around the time of high tide. Rhythms were also examined for ovigerous females collected from estuaries with three different tidal regimes: semi-diurnal, diurnal, and non-tidal. Crabs from the tidal estuaries had circatidal or circalunidian swimming rhythms with period lengths corresponding to the tidal period of their home estuary. Swimming occurred primarily on ebb tide. Crabs from the non-tidal estuary had a circadian rhythm of vertical swimming around the time of sunset. Such a rhythm has no obvious migratory significance and migration likely takes place though another mechanism.</p><p>Swimming behavior was also examined in the field in one non-tidal site and three tidal sites. Crabs were tethered in the field and swimming was monitored using archival pressure tags. Crabs tethered in the non-tidal site did not swim, possibly due to the lack of necessary environmental cues. Crabs at the tidal sites swam primarily on ebb tides. Swimming was greatest at the deepest site, which also had the strongest currents. This site is known to be a migratory area for spawning blue crabs. Decreased swimming behavior was observed at the two shallower sites, including one site that is known to be habitat for all stages of blue crabs. These results indicate that swimming behavior is variable among different areas in a single estuary. In areas where swimming is reduced, crabs may continue migrating seaward by walking or may spend additional time in that area to forage. Within each site, peak swimming generally occurred during the time of the most rapid decrease in water level, suggesting that hydrostatic pressure may serve as a cue for swimming. </p><p>Mark-recapture studies were conducted in three rivers (North River, South River, Adams Creek) in eastern North Carolina, and recently-molted female crabs were tagged to ensure a relatively constant time since molting. Most crabs traveled relatively short distances and were recaptured before producing a clutch of eggs. Individuals that moved substantial distances typically moved down-estuary. The Adams Creek canal, connecting Adams Creek with the Newport River estuary, functioned as a migratory corridor, as crabs from both Adams Creek and South River migrated down the canal, presumably using ebb tide transport. Many of the crabs that migrated down the canal into the Newport River were recaptured while ovigerous. Results of this study support the hypothesis that rapid long-distance migratory movements do not begin until production of the first clutch of eggs, though some down-estuary movement takes place by prior to production of the first clutch of eggs.</p><p>Female blue crabs mate following the terminal molt and begin moving seaward soon thereafter by walking and swimming. Once the appropriate salinity (> 22 ppt) is reached, the first clutch of eggs is produced and migration rate rapidly increases. Blue crab spawning biology should be similar throughout the range of the species. After taking latitudinal temperature variation and other local variables into account, results presented here should be applicable not only to blue crabs in North Carolina, but in other areas as well.</p> / Dissertation