This research provides insight into changes in volumetric flushing of the Tampa Bay estuary caused by synoptic scale wind events. The two main studies of this dissertation involve 1) using wavelet analysis to investigate the link between the El Niño-Southern Oscillation (ENSO) and the frequency and strength of volumetric flushing driven by synoptic variability and 2) using a multi-decadal model simulation to examine how extratropical/winter storms and hurricanes affect the overall flushing rates for Tampa Bay, FL. In the first study, two analyses are performed on 55 years of observational data to investigate the effect of multiple small wind events on estuarine flushing. First I use subtidal observed water level as a proxy for mean tidal height to estimate the rate of volumetric bay outflow. Second, I use wavelet analysis on sea level and wind data to isolate the synoptic sea level and surface wind variance. For both analyses the long-term monthly climatology is removed to focus on the volumetric and wavelet variance anomalies. The overall correlation between the Oceanic Niño index and volumetric anomalies is small (r2=0.097) due to the seasonal dependence on the ENSO response. The mean monthly climatology between the synoptic wavelet variance of elevation and axial winds have similar seasonal behavior. During the winter, El Niño (La Niña) increases (decreases) the synoptic variability, but decreases (increases) it during the summer. The difference in winter El Niño/La Niña wavelet variances is about 20% of the climatological value. ENSO can swing the synoptic flushing of the bay by 0.22 bay volumes per month. These changes in circulation associated with synoptic variability have the potential to impact mixing and transport within the bay. In the second study, volumetric changes from large scale weather events are investigated using a numerical circulation model simulation (1975-2006) to find the cumulative impact of flushing on the bay by extreme events. The strong wind speeds, duration of high winds and wind direction during these events all affect the amount of water flushed in and out of the estuary. Normalized volume anomalies are largest when wind components blow up/down the estuary in the NE/SW direction. Wind induced normalized flushing rates for all 10 extratropical/winter storms range from 12% to 40% and from 14% to 40% for all 10 hurricanes. All storms discussed in this study caused winds greater than 15 m s-1 (~30 knots). The direction of the winds had an impact on the flushing rates during these extreme events. Storm9 (February 1998) and Hurricane Gabrielle (September 2001) experienced the smallest total volume changes (14% and 13%). Both storms experienced weak axial and co-axial winds causing volume changes to be small. The Storm of the Century (March 1993) and Hurricane Frances (September 2004) saw the largest total volume changes of 40%. They both had strong winds blowing in the NE direction. Hurricane Frances had two wind peaks and lingered in the area for approximately 48 hours, so both strength and duration of winds played a large role in the total volume change. Total inflow and outflow rates per year show that there is year to year variability of flushing in Tampa Bay.

As human activity along coastlines increase, degradation and destruction of coastal marine ecosystems around the globe will increase at an alarming rate. In an effort to mitigate degradation and destruction of coastal marine ecosystems, artificial reefs have been used in restoration and enhancement projects. As artificial reefs are the main method of restoring diversity to a degraded area, it is important to know the mechanisms that drive marine community assembly and diversity on those reefs. Understanding community assembly patterns of foundational species, in particular, may provide insight to community assembly patterns at higher trophic levels. Subtidal macroalgae are commonly seen as foundational species in marine environments and both deterministic and stochastic processes play a role in their assembly. Environmental gradients, which are deterministic processes, play a significant role in structuring subtidal macroalgae communities. Depth, which is negatively correlated with light, is the main driver structuring subtidal macroalgal communities, however, other gradients such as water flow, and distance to a propagule source also impact their assembly. This study sought to determine which environmental gradients play a prominent role in subtidal macroalgal community assembly. To study subtidal macroalgal community assembly, 92 artificial reef units called Reef Balls were deployed east of the Ogden Point Breakwater in Victoria, BC in June 2009. Two years passed to allow for macroalgal growth and early successional processes to occur prior to sampling the communities on thirty Reef Balls via underwater collection in July 2011. Algae were sorted by genus and dry weight was measured. To determine effects of environmental gradients on community assembly light, depth, water flow, distance to the nearest Reef Ball and distance to the breakwater were measured at each Reef Ball. A redundancy analysis revealed that depth was the most significant environmental gradient shaping algae communities and had the greatest effect on upper canopy algae. Spatial plots reveal a depth and coastline zonation of algae genera comprising the canopy. While depth was found to significantly structure algae genera found in the canopy, there was a high degree of unexplained variation in the model. This suggests that unmeasured variables such as colonization and priority effects may be driving algal community structure in the lower canopy. Differences in community structure between upper and lower canopy reveal that multiple mechanisms are responsible for shaping subtidal algal communities. Further study is required to determine the importance of stochastic colonization events and priority effects. / Graduate / 0329 / vmucciar@uvic.ca

As human activity along coastlines increase, degradation and destruction of coastal marine ecosystems around the globe will increase at an alarming rate. In an effort to mitigate degradation and destruction of coastal marine ecosystems, artificial reefs have been used in restoration and enhancement projects. As artificial reefs are the main method of restoring diversity to a degraded area, it is important to know the mechanisms that drive marine community assembly and diversity on those reefs. Understanding community assembly patterns of foundational species, in particular, may provide insight to community assembly patterns at higher trophic levels. Subtidal macroalgae are commonly seen as foundational species in marine environments and both deterministic and stochastic processes play a role in their assembly. Environmental gradients, which are deterministic processes, play a significant role in structuring subtidal macroalgae communities. Depth, which is negatively correlated with light, is the main driver structuring subtidal macroalgal communities, however, other gradients such as water flow, and distance to a propagule source also impact their assembly. This study sought to determine which environmental gradients play a prominent role in subtidal macroalgal community assembly. To study subtidal macroalgal community assembly, 92 artificial reef units called Reef Balls were deployed east of the Ogden Point Breakwater in Victoria, BC in June 2009. Two years passed to allow for macroalgal growth and early successional processes to occur prior to sampling the communities on thirty Reef Balls via underwater collection in July 2011. Algae were sorted by genus and dry weight was measured. To determine effects of environmental gradients on community assembly light, depth, water flow, distance to the nearest Reef Ball and distance to the breakwater were measured at each Reef Ball. A redundancy analysis revealed that depth was the most significant environmental gradient shaping algae communities and had the greatest effect on upper canopy algae. Spatial plots reveal a depth and coastline zonation of algae genera comprising the canopy. While depth was found to significantly structure algae genera found in the canopy, there was a high degree of unexplained variation in the model. This suggests that unmeasured variables such as colonization and priority effects may be driving algal community structure in the lower canopy. Differences in community structure between upper and lower canopy reveal that multiple mechanisms are responsible for shaping subtidal algal communities. Further study is required to determine the importance of stochastic colonization events and priority effects. / Graduate / 0329 / vmucciar@uvic.ca

The simultaneous increase in biological invasions and habitat alteration through the building of coastal infrastructure is playing an important role in reshaping the composition and functioning of nearshore marine ecosystems. This thesis examined patterns of marine invasions across anthropogenic and natural habitats and explored some of the processes that influence establishment and spread of invaders. The goals of this thesis were four-fold. First, I examined the habitat distribution of marine nonindigenous species (NIS) spanning several taxonomic groups and geographical regions. Second, I conducted systematic subtidal surveys in anthropogenic and natural habitats and investigated the distribution of nonindigenous ascidians on Southern Vancouver Island, British Columbia, Canada. Third, I tested methods for in-situ larval inoculations and utilized these techniques to manipulate propagule supply and assess post-settlement mortality of ascidians across habitat types. Fourth, I investigated the role of biotic resistance, through predation by native species, on the survival of ascidian colonies in anthropogenic and natural habitats. Results from this research showed that anthropogenic habitats are hubs for marine invasions and may provide beachheads for the infiltration of nearby natural sites. Specifically, a literature review of global scope showed that most NIS are associated with anthropogenic habitats, but this pattern varied by taxonomic group. Most algal and mobile invertebrate NIS were reported from natural habitats, while most sessile NIS were reported from artificial structures. Subtidal field surveys across both anthropogenic and natural habitats showed that nonindigenous ascidians were restricted largely to artificial structures on Southern Vancouver Island and that this pattern is consistent across their global introduced ranges. Field manipulations using the ascidian Botrylloides violaceus as a model organism, showed that post-settlement mortality is high and that large numbers of larvae or frequent introduction events may be needed for successful initial invasion and successful infiltration of natural habitats. Experiments also showed that predation by native species can limit the survival of B. violaceus in anthropogenic and natural habitats. This dissertation contributes knowledge about the patterns and processes associated with habitat invisibility; provides insight into factors affecting colonization; and supplies valuable information for predicting and managing invasions. / Graduate / 0329

Marine and aquatic species relying on external fertilization must have special adaptation against sperm-dilution in the water. In addition mating competition may be another important source of limitation to an individual¡¦s reproductive success. If the two above mechanisms are in direct conflict, real adaptation would reflect whichever is more critical to one¡¦s fitness. In using the same logic, the unidirectional induction of spawning, i.e., females inducing males, but not males inducing females, has been reported as an evidence for the relative importance of natural selection, that is, sperm-dilution, in limiting the fitness of brittlestars in shallow waters. If the above deduction is correct, one would predict more adaptations to offset the adverse effect of sperm-dilution in various aspects of spawning-related characteristics. Two species of brittlestars. Ophiocoma dentata, living in subtidal zone, and O. scolopendrina, living in intertidal zone, were studied at Kenting, southern Taiwan. Experimental approaches were adopted to figure out if these two species have any adaptation in space and in time that can perceivably counteract the effect of sperm dilution. Spatially, the male O. dentata has the ability to search for females, and the males living with females have higher rates of responding to female spawn than unpaired males; the males do not actively search for eggs released in the water. In O. scolopendrina, neither male nor female had the ability to distinguish the sex of other individuals, they do not form pairs in nature. Males, however, have strong ability to search released eggs and then approach and spawn near the eggs. Temporally, the males of the O. scolopendrina, are sensitive to tidal rhythms in terms of inducibility by female spawns, they only spawn at the time of low tide. The possible effect of water level and photophase were both ruled out. In contrast, no such tidal rhythms of male inducibility was found in the subtidal O. dentata. Sexual selection needs not be invoked in any of the above behaviors, whereas natural selection against sperm dilution is an acceptable explanation. Last, the male O. scolopendrina displays interference behavior by blocking other males from approaching eggs are in the water. The blocked individuals are less likely to spawn.

L'état et l'évolution des écosystèmes côtiers font partie des principales préoccupations des institutions européennes. Leur fonctionnement global et leur structure sont fortement conditionnés par le comportement des premiers échelons de la chaîne alimentaire, et en particulier par les micro-algues qui se développent dans la colonne d’eau (phytoplancton) et au niveau du sédiment (microphytobenthos).Ces microalgues constituent les plus importants producteurs primaires des zones côtières (Pannard et al., 2008 ; Woelfel et al., 2010). Ils sont à la base de la chaine trophique et composent l’essentiel de la nourriture de la faune, en particulier des espèces économiquement importantes (praires, huîtres,….). Cependant, bien que le phytoplancton ait été largement étudié, le microphytobenthos est beaucoup moins connu, en particulier dans les zones subtidales. Il colonise tous les milieux (roche, vase…) dès lors qu’il y a suffisamment de lumière pour la photosynthèse (MacIntyre et al. 1996) et sa production peut égaler, voire même dépasser, la production du phytoplancton de la colonne d’eau qui le surplombe (Underwood and kromkamp, 1999). Dans cette étude, nous avons effectué un suivi hebdomadaire en Rade de Brest (55 sorties en mer en 2011), pour étudier simultanément la dynamique saisonnière du phytoplancton et du microphyto-benthos en relation avec les paramètres environnementaux.Nos résultats montrent que la dynamique du phytoplancton et du microphytobenthos dans la zone subtidale sont tout à fait différentes l’une de l'autre. Le microphytobenthos est le premier à se développer dans la saison. Il constitue un apport important d'énergie dans l'écosystème dès le début du printemps (avec 60% de la biomasse totale jusqu'en avril) et joue donc un rôle primordial dans le démarrage de l’activité biologique benthique. Le système se déplace ensuite d'un système dominé par la biomasse benthique au début du printemps, vers un système où la biomasse pélagique prend le dessus.Ces résultats mettent en évidence l’adaptation particulière du microphytobenthos aux faibles éclairements, puisqu’il est capable de produire la même biomasse que le phytoplancton de la colonne d’eau, mais avec 10 fois moins de lumière disponible. Le broutage par les hétérotrophes peut sans doute expliquer le déclin des biomasses microalgales et la différence de dynamique saisonnière après les premières floraisons. Le manque de nutriments, et en particulier les phosphates dissous dans l’eau pourrait aussi être avancé pour expliquer la chute de la biomasse microphytobenthique début d’avril, alors que le déclin du phytoplancton dans la première semaine du mois de mai coïncide à une carence en acide silicique. L’azote inorganique dissous devient ensuite potentiellement limitant dans la colonne d'eau avec des concentrations en dessous du seuil de détection, jusqu'à la fin d'octobre. D’un point de vue taxonomique, la communauté benthique est très spécifique et totalement différente de la communauté pélagique. Nous avons pu identifier 54 espèces, exclusivement des diatomées, toutes pennées, dominées par le genre Navicula. Dans la colonne d’eau, nous avons identifié 74 espèces, parmi lesquelles 51 étaient des diatomées (essentiellement centriques), dominées par Chaetoceros sp.. Le reste était partagé entre les dinoflagellés (dominé par Gymnodium sp.) et d’autres groupes fonctionnels comme les euglena, les cryptophycées, les prasinophycées, quelques rares coccolithophoridés et des petits flagellés non identifiés.Ces résultats très novateurs ouvrent de nouvelles perspectives de recherches. Il serait par exemple très intéressant de mieux comprendre les processus d’adaptation qu’ont développés les microalgues benthiques, pour être capables à des niveaux de lumière beaucoup plus faibles, d’être aussi efficace vis-à-vis de la photosynthèse que leurs homologues pélagiques. Différentes pistes sont à l’étude comme le contenu pigmentaire ou la structure de leur enveloppe siliceuse. / The most important primary producer groups of the coastal zones are suspended phytoplankton cells (Pannard et al, 2008) and microphytobenthos (MPB) (Woelfel et al., 2010). In these regions, phytoplankton and benthic microalgae are both recognized as being principal components of the diet for economically important suspension-feeding fauna (Gillespie et al., 2000). However, although phytoplankton has been vastly documented, MPB is often understudied.In sufficient light for photosynthesis they can inhabit the top few centimeters of the substrate layers (mud or sand) of marine sediment (Charpy and Charpy-Roubaud 1990, MacIntyre et al. 1996, MacIntyre and Cullen 1996) and play an important role as a food source for higher trophic levels (Revsbech et al. 1981, Sorokin 1991, Charpy and Charpy-Roubaud 1990 ). Benthic microalgal biomass mostly follows a similar distribution to the total organic matter content of surficial sediments indicating that sediment geochemical processes such as nutrient release from the breakdown of organic matter may be important in determining the distribution of MPB (Light, 1998). However, on the other hand, though not proportional with the MPB biomass, benthic production can even surpass the pelagic contribution (Underwood and kromkamp, 1999). With their ability of high primary production benthic microalgal communities can profoundly influence the flux, transformation and turnover of carbon and nutrients in coastal areas. Benthic primary producers contribute to the availability of energy and matter for benthic and pelagic food webs and define benthic and pelagic energy budgets, which affect the chemistry at the sediment-water interface, and regulate sediment stability. The shallow waters, where MPB thrives, allow a more direct interaction between pelagic and benthic processes keeping the benthos much less susceptible to physical and biochemical disturbances such as evaporation, eutrophication, and wind-forcing (Molen, 2011). Because attached microalgae can avoid advective processes and adapt to changes in light availability at short time scales, their importance is particularly enhanced (Phinney, 2004). As a result of the impact that MPB carries in a coastal ecosystem, along with the study of the functional role of MPB, investigations on their diversity have also gained some importance in the last two decades (Sundbaeck & Joensson, 1988; Blanchard, 1990; Montagna et al., 1995). Like phytoplankton, MPB communities can also act as sensitive indicators of water quality as the taxonomic composition of MPB assemblages can vary as per different nutrient levels (Lange-Bertalot, 1979; Kann, 1986). However, although the importance of MPB has been emphasized on intertidal zones (Pinckney & Zingmark, 1993; Colijn & De Jonge, 1984; Herman et al., 2000), the subtidal zones have generally been ignored till yet on this regard and as a result of which not much is known about the MPB dynamics in the subtidal zones. The subtidal zone of Bay of Brest was chosen for this study because there had been comprehensive input of nitrates to the zone in the past century .This zone has being amazingly resistant to eutrophication for quite some time, although silicate and nitrate ratio got down during the past 20 years. Research has been done previously on the spatial distribution of MPB in the zone in terms of primary productivity and biomass, but in order to achieve a more holistic view of these important photoautotrophs, a temporal study is necessary as well. The objectives of this work have been to characterize the temporal distribution of MPB in terms of biomass, productivity and biodiversity in the subtidal zone of Bay of Brest on a monthly scale, assess a comparative reasoning between MPB and the phytoplankton of the overlying water column complying on the same factors and draw an understanding on the significance of seasonal fluctuations of MPB in the overall seasonal distribution of photoautotrophs. […]

Este trabalho foi desenvolvido dentro do contexto da hidrodinâmica da plataforma continental, com o objetivo de estudar a variabilidade subinercial das correntes no extremo norte na Plataforma Continental Sudeste brasileira. A região de estudo está localizada nas proximidades de Cabo Frio (RJ) e Arraial do Cabo (RJ) (aproximadamente 23º S / 42º W). Apesar de ser uma região bastante conhecida e estudada, em função do fenômeno da ressurgência costeira que ocorre em suas proximidades, pouco se conhece sobre a circulação subinercial nessa localidade. Devido à importância das correntes subinerciais, por serem responsáveis pelo transporte de substâncias dissolvidas ou em suspensão nas águas, tais como sedimentos, nutrientes e poluição, este trabalho tenta contribuir com um maior conhecimento desses campos de corrente, a partir da análise, no domínio do tempo e da frequência, de séries temporais de intensidade e direção das correntes e do vento local. Foram utilizados dados coletados no Projeto DEPROAS (Dinâmica do Ecossistema de Plataforma da Região Oeste do Atlântico Sul) a partir de correntógrafos e ADCP fundeados, numa radial em frente a Cabo Frio, sobre as isóbatas de 50, 100 e 200 m, bem como de uma bóia e de uma estação meteorológicas. Trabalhamos com as séries temporais do inverno de 2001 e do inverno e verão de 2003. A partir desse estudo foi possível verificar que a variabilidade subinercial domina o fluxo das correntes na região, principalmente na direção paralela à batimetria. Como no restante da PCSE, verificou-se um balanço geostrófico na direção normal à topografia, responsável por um fluxo paralelo às isóbatas, em especial na PCM e nas profundidades intermediárias afastadas das camadas limite. Foi observado que a corrente costeira, forçada por processos baroclínicos e pelo vento, típica da parte central da PCSE, atinge o extremo norte da plataforma continental, induzindo um fluxo mais frequente com sentido SE, nas camadas intermediária e de fundo, principalmente no inverno. Verificou-se também que os ventos locais têm baixa correlação com as correntes, exceto nos níveis superficiais, evidenciando a importância das forçantes remotas na dinâmica da região, somado à influência da atividade vortical ciclônica gerada na região pela Corrente do Brasil, com influência até a PCM. Evidências de eventos de ressurgência/subsidência apareceram ao longo de todos os períodos estudados, com ocorrência preferencial a W desta localidade. / This work was developed within the context of the continental shelf hydrodynamics, with the aim of studying the subtidal variability of the currents in the far north of the South Brazil Bight (SBB). The area of the study is located in the vicinity of Cabo Frio (RJ) and Arraial do Cabo (RJ) (approximately 23º S / 42º W). Despite being a well known and studied region, due to the coastal upwelling phenomenon that occurs in its vicinity, little is known about the subtidal variability in this location. Given the importance of the subtidal currents, that are responsible for the transport of substances dissolved or suspended in water, such as sediments, nutrients and pollution, this work tries to contribute to a better understanding of these current~ fields, by the analysis in the time and frequency domain, from time series of the currents and local wind intensity and direction. We used data collected in DEPROAS Project (Western South Atlantict Platform Ecosystem Dynamics) from current meters and an ADCP moored in front of Cabo Frio, on the isobaths of 50, 100 and 200 m, and from a buoy and a weather station. We worked with time series of 2001 winter and 2003 winter and summer. From this study it was found that the subtidal variability dominates the flow in the region, mainly in the parallel direction of the bathymetry. As in the rest of the SBB, there was a geostrophic balance in the normal direction of the topography, which accounts for a flow parallel to isobaths, particularly in the middle shelf and in intermediate depths of the remote boundary layer. It was observed that the coastal current forced by baroclinic processes and by the wind, typical of the central part of the SBB reaches the northern edge of the SBB, leading to a more frequent flow in the southeast direction, in the intermediate layers and the bottom, especially in the winter. It was also found that the local winds have low correlation with the currents, except on the superficial layers, indicating the importance of remote forcing in the dynamics of the region, coupled with the influence of cyclonic vortical activity in the region, generated by the Brazil Current, reaching the middle shelf. Upwelling and downwelling evidences were observed in all time series, with the preferential location occurring west of Cabo Frio.

Este trabalho foi desenvolvido dentro do contexto da hidrodinâmica da plataforma continental, com o objetivo de estudar a variabilidade subinercial das correntes no extremo norte na Plataforma Continental Sudeste brasileira. A região de estudo está localizada nas proximidades de Cabo Frio (RJ) e Arraial do Cabo (RJ) (aproximadamente 23º S / 42º W). Apesar de ser uma região bastante conhecida e estudada, em função do fenômeno da ressurgência costeira que ocorre em suas proximidades, pouco se conhece sobre a circulação subinercial nessa localidade. Devido à importância das correntes subinerciais, por serem responsáveis pelo transporte de substâncias dissolvidas ou em suspensão nas águas, tais como sedimentos, nutrientes e poluição, este trabalho tenta contribuir com um maior conhecimento desses campos de corrente, a partir da análise, no domínio do tempo e da frequência, de séries temporais de intensidade e direção das correntes e do vento local. Foram utilizados dados coletados no Projeto DEPROAS (Dinâmica do Ecossistema de Plataforma da Região Oeste do Atlântico Sul) a partir de correntógrafos e ADCP fundeados, numa radial em frente a Cabo Frio, sobre as isóbatas de 50, 100 e 200 m, bem como de uma bóia e de uma estação meteorológicas. Trabalhamos com as séries temporais do inverno de 2001 e do inverno e verão de 2003. A partir desse estudo foi possível verificar que a variabilidade subinercial domina o fluxo das correntes na região, principalmente na direção paralela à batimetria. Como no restante da PCSE, verificou-se um balanço geostrófico na direção normal à topografia, responsável por um fluxo paralelo às isóbatas, em especial na PCM e nas profundidades intermediárias afastadas das camadas limite. Foi observado que a corrente costeira, forçada por processos baroclínicos e pelo vento, típica da parte central da PCSE, atinge o extremo norte da plataforma continental, induzindo um fluxo mais frequente com sentido SE, nas camadas intermediária e de fundo, principalmente no inverno. Verificou-se também que os ventos locais têm baixa correlação com as correntes, exceto nos níveis superficiais, evidenciando a importância das forçantes remotas na dinâmica da região, somado à influência da atividade vortical ciclônica gerada na região pela Corrente do Brasil, com influência até a PCM. Evidências de eventos de ressurgência/subsidência apareceram ao longo de todos os períodos estudados, com ocorrência preferencial a W desta localidade. / This work was developed within the context of the continental shelf hydrodynamics, with the aim of studying the subtidal variability of the currents in the far north of the South Brazil Bight (SBB). The area of the study is located in the vicinity of Cabo Frio (RJ) and Arraial do Cabo (RJ) (approximately 23º S / 42º W). Despite being a well known and studied region, due to the coastal upwelling phenomenon that occurs in its vicinity, little is known about the subtidal variability in this location. Given the importance of the subtidal currents, that are responsible for the transport of substances dissolved or suspended in water, such as sediments, nutrients and pollution, this work tries to contribute to a better understanding of these current~ fields, by the analysis in the time and frequency domain, from time series of the currents and local wind intensity and direction. We used data collected in DEPROAS Project (Western South Atlantict Platform Ecosystem Dynamics) from current meters and an ADCP moored in front of Cabo Frio, on the isobaths of 50, 100 and 200 m, and from a buoy and a weather station. We worked with time series of 2001 winter and 2003 winter and summer. From this study it was found that the subtidal variability dominates the flow in the region, mainly in the parallel direction of the bathymetry. As in the rest of the SBB, there was a geostrophic balance in the normal direction of the topography, which accounts for a flow parallel to isobaths, particularly in the middle shelf and in intermediate depths of the remote boundary layer. It was observed that the coastal current forced by baroclinic processes and by the wind, typical of the central part of the SBB reaches the northern edge of the SBB, leading to a more frequent flow in the southeast direction, in the intermediate layers and the bottom, especially in the winter. It was also found that the local winds have low correlation with the currents, except on the superficial layers, indicating the importance of remote forcing in the dynamics of the region, coupled with the influence of cyclonic vortical activity in the region, generated by the Brazil Current, reaching the middle shelf. Upwelling and downwelling evidences were observed in all time series, with the preferential location occurring west of Cabo Frio.

In Nova Scotia subtidal habitats, the invasive bryozoan Membranipora membranacea interacts with native bryozoan Electra pilosa on kelps, which offer high space availability but are highly dynamic, and on non-kelp algae, which provide low space but high stability. Settlers and colony cover of M. membranacea at various stages critical to its population dynamics, as well as relative abundance and encounter outcomes of M. membranacea and E. pilosa, were quantified on these substrates. I also examined the effects of various factors on growth rates of E. pilosa. For M. membranacea populations, the roles of kelp and non-kelp substrates varied intra- and inter-annually, as well as spatially. Membranipora membranacea was relatively more abundant on kelps than on Fucus, likely due to large colony size, faster growth, and strong overgrowth abilities. While kelps provide spatial resources for seasonal peaks in abundance of M. membranacea, non-kelp refuges can preserve local populations in time.

The Black Prince Limestone of southeastern Arizona has been assigned to the Morrowan on the basis of several long-ranging fossils. Since these were not especially diagnostic, the exact time represented by the Black Prince within the Morrowan was uncertain. To date the Black Prince more precisely, six sections were systematically sampled for conodonts. The condonts found, especially Neognathodus bassleri, Rachistognathus muricatus, Idiognathoides convexus, and Spathoqnathodus coloradoensis, indicate a middle Morrowan to early Derryan age for the Black Prince in the study area. Four conodont zones can be recognized: the Neognathodus bassleri Zone, the Idiognathodus sinuosis.- Streptognathodus anteeccentricus Zone , the Idiognathoides convexus Zone, and the Spathognathodus coloradoensis-Neognathodus columbiensis Zone. These zones compare favorably with the zonation previously established in the type Morrowan. This biostratigraphic evidence suggests that the hiatus between the Black Prince and Horquilla Limestones increases in magnitude from southeastern to south-central Arizona. The Black Prince represents a sequence of tidal flat and shallow subtidal carbonate deposits. Mudstones and sparsely fossiliferous wackestones with low fossil diversity and abundance characterize the tidal-flat facies. Grainstones, packstones, and fossiliferous wackestones with high fossil diversity and abundance characterize the shallow subtidal facies.