Coral reef fish are known to have a bipartite life cycle: a dispersive pelagic larval phase (DPL), where larvae ‘travel’ away from their parents to occupy new habitats, and a sedentary reef phase characterized by juveniles and adults. Study of the DPL is an essential prerequisite to understand how persistence, connectivity, and gene flow operate between populations. Clownfish have been the subject of considerably varied fields of research in recent decades, not only due to their economic value, but also because of their ease of maintenance in laboratory settings, regular spawning, and short DPL. Their life cycle is also defined as bipartite, with a DPL lasting around 15 days until settlement, and the fish exhibit a symbiotic relationship with sea anemones. The transitions between phases are associated with a series of morphological, behavioural, genetic, cellular and molecular changes. However, these changes are poorly characterized in some species of clownfish. Therefore, the Red Sea clownfish, Amphiprion bicinctus, was reared to fill the gap in the literature by investigating their i) morphology, ii) swimming abilities, and iii) differential gene expression (DGE) throughout ontogeny. The DPL was characterized in the preflexion, flexion and postflexion stages, according to flexion of the notochord, on 0, 2 and 10 days post hatch (dph), respectively. Metamorphosis was defined by a morphological transition between the DPL and juvenile phases, associated with the appearance of white stripes, on day 10 and until the end of the experiment, on day 14. Additionally, metamorphosis is followed by a behavioural change at 14 dph, called settlement, where larvae transition from free swimming in the water column to associating with the substrate. We also demonstrate that the larvae present active swimming from the moment they hatch, and the swimming speed increases throughout DPL. Overall, the development of A. bicinctus is similar to other clownfish species. This work provides a strong baseline on the development of A. bicinctus, which may open the door to a deeper understanding of the role of dispersal behaviours and enhance our ability to design effective marine reserve networks in the Red Sea.

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.

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

L'industrie de la pêche est confrontée à plusieurs contraintes comme l'augmentation du prix du carburant et la diminution des stocks de poisson. Pour améliorer la rentabilité, nous avons fait l'optimisation des chaluts de pêche (pélagique et de fond) afin d'augmenter leurs efficacités énergétiques. Deux facteurs principaux ont été utilisés : la traînée du chalut et sa surface balayée. Notre travail porte sur l'optimisation du plan du chalut par modification du nombre de mailles des pièces du filet et par changement de la longueur des câbles. Nous avons développé une méthode de recherche successive appelée SOT et nous l'avons comparée à une méthode de recherche aléatoire dans le cas d'un chalut pélagique avec un gain net de 54%. La SOT a été utilisée pour optimiser le plan des pièces du filet d'un chalut de fond. Une amélioration du gain énergétique de 38% a été obtenue, ainsi qu'une réduction de 45 jours de pêche. Par souci de risque de baisse de capturabilité, nous avons développé une fonction objectif qui dépend de la distribution de poisson. Trois fonctions de même densité surfacique ont été testées. L'amélioration de l'efficacité énergétique calculée par la méthode SOT sur un chalut de fond est respectivement de 52%, 16% et 32% selon les trois distributions. Avec la méthode SRT (méthode de raffinement séquentiel), nous obtenons des réductions de 56%, 30% et 39% pour les trois distributions. Finalement nous avons adapté la méthode SOT pour optimiser les longueurs des câbles du chalut. Nous obtenons dans un cas une amélioration de l'efficacité énergétique de 49%. L'utilité de ce travail devrait être étendue hors de la pêche comme l'écologie en général. / Nowadays, fishing industry is facing several constraints such as increased fuel prices and declining fish stocks. In this work, we perform optimization of fishing trawls (pelagic and bottom) in order to improve their energy efficiencies. Two main factors were used: the trawl drag and its mouth swept area. Our work focuses on optimizing trawl design by altering mesh numbers and changing cable length. We have developed a method called SOT and compared it to a random search method in the pelagic trawl case with a net energy gain of 54%. The SOT was used in design optimization of bottom trawl panels. Improved energy gain of 38% was obtained and a reduction of 45 total number of fishing days. In order to bypass catchability reduction, we developed an objective function which depends on fish distribution. Three functions with same bottom surface density were tested. Improving energy efficiency calculated by the SOT method on a bottom trawl is respectively 52%, 16% and 32% for the three distributions. With the SRT method (sequential refinement), we obtain reductions of 56%, 30% and 39% for the three aforementioned distributions. Finally we adapted the SOT method to optimize trawl cable lengths. In one case, we obtain energy efficiency improved by 49%. The usefulness of this work should be extended beyond fishery to ecology in general.

Foram estudadas a composição e a distribuição da abundância e da biomassa de grupos do microzooplâncton na plataforma e no talude da Bacia de Campos localizados na região sudeste da margem continental do Brasil, compreendida entre Vitória (20,5°S) e Cabo Frio (24°S). Foram coletadas amostras de microzooplâncton com rede Multinet de 64 ?m por meio de arrastos horizontais em cinco estratos de profundidade (do superficial ao batipelagial até 2300 m) e em dois períodos: período um (P1) março-abril/2009 e período dois (P2) agosto-setembro/2009. A abundância total variou de 1 a 56918 org./m³ no P1 e de 80 a 206732 org./m³ no P2, enquanto a biomassa total variou entre 2x10-5 e 2 mg/m³ no P1 e de 6x10-6 a 5 mg/m³ no P2. Os grupos taxonômicos mais frequentes (> 50% Frequência realtiva) no P1 foram Radiolaria, Tintinnina, Foraminifera, náuplios de Copepoda, Cyclopoida, Calanoida, Gastropoda, Pteropoda e Bivalvia. Já no P2 foram: Acantharia, Radiolaria, Tintinnina, Foraminifera, náuplios de Copepoda, Cyclopoida, Calanoida, Harpacticoida, Gastropoda, Bivalvia e Polychaeta. Os náuplios de Copepoda dominaram nasuperfície, com 65% de abundância relativa no P1 e P2, ao passo que organismos do protozooplâncton, como Radiolaria, Tintinnina e Foraminifera, foram os mais abundantes em águas profundas. Houve diferenças na abundância e na biomassa em resposta às variações ambientais, espaciais e sazonais na Água Tropical (AT-1 m) e Água Central do Atlântico Sul (ACAS-250 m). Estas variações podem estar relacionadas à ascenção de águas profundas ricas em nutrientes da ACAS até a zona eufótica, o que leva ao aumento de produtividade e ao aumento da produção primária em domínios neríticos da região, associado à frequente ocorrência de vórtices ciclônicos associados à Corrente do Brasil. Porém, nos estratos mais profundos (Água Intermediária Antártica (AIA-800 m), Água Circumpolar Superior (ACS-1200 m) e Água Profunda do Atlântico Norte (APAN-2300 m)), notou-se homogeneidade horizontal do microzooplâncton, associada à maior estabilidade termohalina. No entanto, vale ressaltar que os altos valores de Radiolaria nas águas profundas poderiam estar condicionados às características físicas e químicas da ACS. Neste trabalho foi possível concluir que a abundância e a biomassa do microzooplâncton foram maiores na camada superficial e na ACAS, devido as flutuações de temperatura e salinidade. Notou-se também uma variabilidade entre os períodos de coleta. A temperatura foi a variável que mais influenciou as concentrações de organismos, em contraste, a baixa flutuação da salinidade na Bacia de Campos não influenciou significativamente os grupos do microzooplâncton. Os dados da AIA, ACS e APAN obtidos neste trabalho são fundamentais para o conhecimento do ambiente meso e batipelagial ao longo do Brasil. Finalmente, a FlowCAM, utilizada para a análise semiautomática das amostras, foi uma ferramenta útil para a contagem e obtenção de informações morfométricas sobre o microzooplâncton. / The composition and the distribution of numerical abundance and biomass of microzooplankton groups were sutudied in the Campos Basin located southeastern Brazil, between Victoria (20.5°S) and Frio Cape (24°S). Microzooplankton samples were collected with horizontal hauls using a Multinet (64 ?m) in five depth layers (surface up to 2300m bathypelagial zone) and in two seasonal periods: Period one (P1) May, April - 2009 and Period two (P2) August, September - 2009 (HABITATS CENPES / PETROBRAS). The total abundance ranged from 1 to 57 Org/m³ during the P1 and from 80 to 207 Org/m³ during the P2. Total biomass ranged from 2x10-5 to 2 mg/m³ during the P1, and from 6x10-6 to 5 mg/m³ during the P2. Most frequent taxonomic groups (> 50% relative frequency) in P1 were Radiolaria, Tintinnina, Foraminifera, Copepod nauplii, Cyclopoida, Calanoida, Gastropoda, Pteropoda, and Bivalvia. In P2, the most frequent taxonomic groups were Acantharia, Radiolaria, Tintinnina, Foraminifera, Copepod nauplii, Cyclopoida, Calanoida, Harpacticoida, Gastropoda, Bivalvia, and Polychaeta. Copepod nauplii dominated the surface samples, with 65% of relative abundance during both periods; Radiolaria, Tintinnina and Foraminifera dominated the deep water samples. There were differences in the abundance and biomass in response to environmental, spatial and seasonal variationsn the Tropical Water (TW-1 m) and in the South Central Atlantic Water (SCAW-250 m), These variations may related tothe rise of nutrient-rich deep waters of the SCAW to the euphotic zone, which leads to the increase of the productivity and the increase of the primary production in neritic areas, linking it to the frequent occurrence of cyclonic vortices associated with Brazil Current. In the deepest layers Antarctic Intermediate Water (AAIW-800 m), Upper Circumpolar Water (UCW-1200 m) and North Atlantic Deep Water (NADW-2300 m) it was noted a horizontal homogeneity of the microzooplankton associated with thermohaline stability. However, it is noteworthy that the high values of Radiolaria in deep water could be conditioned by the physical and chemical characteristics of the UCW. It was possible to conclude thatthe abundance and biomass of microzooplankton were higher in the surface layer and SCAW, f due to climatic fluctuations of temperature and salinity.. The temperature was the variable that most influenced the concentrations of organisms; in contrast, the low salinity fluctuations in the Campos Basin had no significant influence on the groups of microzooplankton. The data from AAIW, UCW, and NADW obtained in this work are fundamental for the understanding of the mesopelagical and bathypelagical zones in the Brazilian oceanic waters. Finally the FlowCAM used for semi-automatic analysis of samples was a useful tool for counting and obtaining information about the morphometric microzooplankton.

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.

Les contextes national et international sont marqués par une prise de conscience de plus en plus grande de l’importance du poisson pour la sécurité alimentaire des populations des pays sous-développés. En Mauritanie, les petits pélagiques constituent une source de protéines animales accessibles aux faibles pouvoirs d’achat et contribuent à garantir la sécurité alimentaire de nombreuses populations. Malgré la présence d’une variabilité naturelle importante des espèces pélagiques, ce travail de thèse montre qu’il existe des éléments de stabilité dans l’écosystème pélagique dans la zone nord-ouest africaine. L’hypothèse de la présence des stocks sédentaires au niveau des zones de nourriceries en Mauritanie et au Sénégal est démontrée. La répartition spatio-temporelle des sardinelles en relation avec la dynamique de l’océan (upwelling, température de surface et chlorophylle) a été examinée. L’analyse des statistiques de la pêche sur une série de plus de trente (30) ans ne soutiennent pas l’immigration en provenance du Sénégal vers la Mauritanie d'Avril à Septembre selon l’hypothèse de Boëly (1978). Ce travail de thèse examine des hypothèses de migrations possibles des sardinelles dans la zone nord-ouest africaine et d’importantes implications en matière de gestion sont discutées. Pour finir, ce travail est replacé dans son contexte plus global de l’aménagement de la pêcherie des petits pélagiques. De nouvelles perspectives pour l’application des techniques géostatistiques (indicatrices et co-krigeage) et modélisation statistique sont envisagées pour l’étude de la dynamique des stocks des sardinelles et chinchards. / National and international context marked by an awareness of growing importance of pelagic fish for food security of people in underdeveloped countries . The depletion of demersal species also makes this extremely important resource for the future pelagic fisheries in Mauritania. Mauritanian EEZ is characterized by the existence of a favorable development of several species hydro-climatic and morphological phenomena , small pelagic species that represent more than 90% of the fisheries potential is about one million tones. The major problems facing the management of these species is understanding the roles played by them in their biogeography intrinsic spatio- temporal dynamics ( short-lived , aggregation , etc. ..) and the evaluation of their abundances . Assessment of exploited fish stocks is a priority. However, the recurring difficulty of evaluations of these fisheries, naturally very unstable, often reflected a lack of precision in the methods used , the incompleteness of the data ( which is also a problem of sampling) or sampling uncontrolled .The Mauritanian small pelagic fisheries are multi-species (sardines , horse mackerel , sardinella ) . In addition to the data provided by the logbooks including the holding is mandatory for industrial units, survey data for the landing craft and coastal segment often used to calculate the abundance, acoustic surveys , are an important means for quantify the abundance and study the distribution of these resources. The data collected by observers on board fishing industrial units are also a source of important information.Based on these data , this work aims at the reconstruction of the main series of abundances of small pelagic stocks in the northern part of West Africa , to be used in the adjustment of stock assessments models. Given the importance of the environmental component in very large fluctuations observed, the integration of this dimension in the analysis of this series catches the role of each of these factors (fisheries and environment) in the variability of abundance seasonal and amplitude of their migration.In addition to these conventional data Mauritania introduced on board commercial fishing vessels with VMS . This system allows the transmission by satellite to the body control the ship's position every hour is an important technological advance. This new type of data could therefore be a new source for estimating abundance and fishing effort of small pelagic species through appropriate statistical methods. A method for the interpretation in terms of paths abundance index was applied. The coupling of VMS and logbook will help to improve the definition of nominal fishing effort and catch location at fine spatial and temporal.The general problem is how to improve the estimation of the abundance of small pelagic stocks , understand fluctuations in the abundance and migration strategy of the species as well as tactics and strategies implemented by fleets to fish resources whose behavior is often erratic . It is therefore to adresse several issues in particular:What is the trend of the evolution of the abundance of pelagic species in the North West African area? The interpretation of the trajectories in terms of VMS fishing can it be used to map the abundance of key species? What are the seasons abundances? Environmental parameters they play an important role on the distribution of species? Will there a difference between tactics and strategies of the different fleets fishing for small pelagic? Data logs and data collected by observers on board can be used as a priori knowledge? To address these issues , we proceed to the mobilization of all relevant time series and implement innovative statistical and geostatistical methods , some of which applied for the first time in the sub -region for these stocks.

Foram estudadas a composição e a distribuição da abundância e da biomassa de grupos do microzooplâncton na plataforma e no talude da Bacia de Campos localizados na região sudeste da margem continental do Brasil, compreendida entre Vitória (20,5°S) e Cabo Frio (24°S). Foram coletadas amostras de microzooplâncton com rede Multinet de 64 ?m por meio de arrastos horizontais em cinco estratos de profundidade (do superficial ao batipelagial até 2300 m) e em dois períodos: período um (P1) março-abril/2009 e período dois (P2) agosto-setembro/2009. A abundância total variou de 1 a 56918 org./m³ no P1 e de 80 a 206732 org./m³ no P2, enquanto a biomassa total variou entre 2x10-5 e 2 mg/m³ no P1 e de 6x10-6 a 5 mg/m³ no P2. Os grupos taxonômicos mais frequentes (> 50% Frequência realtiva) no P1 foram Radiolaria, Tintinnina, Foraminifera, náuplios de Copepoda, Cyclopoida, Calanoida, Gastropoda, Pteropoda e Bivalvia. Já no P2 foram: Acantharia, Radiolaria, Tintinnina, Foraminifera, náuplios de Copepoda, Cyclopoida, Calanoida, Harpacticoida, Gastropoda, Bivalvia e Polychaeta. Os náuplios de Copepoda dominaram nasuperfície, com 65% de abundância relativa no P1 e P2, ao passo que organismos do protozooplâncton, como Radiolaria, Tintinnina e Foraminifera, foram os mais abundantes em águas profundas. Houve diferenças na abundância e na biomassa em resposta às variações ambientais, espaciais e sazonais na Água Tropical (AT-1 m) e Água Central do Atlântico Sul (ACAS-250 m). Estas variações podem estar relacionadas à ascenção de águas profundas ricas em nutrientes da ACAS até a zona eufótica, o que leva ao aumento de produtividade e ao aumento da produção primária em domínios neríticos da região, associado à frequente ocorrência de vórtices ciclônicos associados à Corrente do Brasil. Porém, nos estratos mais profundos (Água Intermediária Antártica (AIA-800 m), Água Circumpolar Superior (ACS-1200 m) e Água Profunda do Atlântico Norte (APAN-2300 m)), notou-se homogeneidade horizontal do microzooplâncton, associada à maior estabilidade termohalina. No entanto, vale ressaltar que os altos valores de Radiolaria nas águas profundas poderiam estar condicionados às características físicas e químicas da ACS. Neste trabalho foi possível concluir que a abundância e a biomassa do microzooplâncton foram maiores na camada superficial e na ACAS, devido as flutuações de temperatura e salinidade. Notou-se também uma variabilidade entre os períodos de coleta. A temperatura foi a variável que mais influenciou as concentrações de organismos, em contraste, a baixa flutuação da salinidade na Bacia de Campos não influenciou significativamente os grupos do microzooplâncton. Os dados da AIA, ACS e APAN obtidos neste trabalho são fundamentais para o conhecimento do ambiente meso e batipelagial ao longo do Brasil. Finalmente, a FlowCAM, utilizada para a análise semiautomática das amostras, foi uma ferramenta útil para a contagem e obtenção de informações morfométricas sobre o microzooplâncton. / The composition and the distribution of numerical abundance and biomass of microzooplankton groups were sutudied in the Campos Basin located southeastern Brazil, between Victoria (20.5°S) and Frio Cape (24°S). Microzooplankton samples were collected with horizontal hauls using a Multinet (64 ?m) in five depth layers (surface up to 2300m bathypelagial zone) and in two seasonal periods: Period one (P1) May, April - 2009 and Period two (P2) August, September - 2009 (HABITATS CENPES / PETROBRAS). The total abundance ranged from 1 to 57 Org/m³ during the P1 and from 80 to 207 Org/m³ during the P2. Total biomass ranged from 2x10-5 to 2 mg/m³ during the P1, and from 6x10-6 to 5 mg/m³ during the P2. Most frequent taxonomic groups (> 50% relative frequency) in P1 were Radiolaria, Tintinnina, Foraminifera, Copepod nauplii, Cyclopoida, Calanoida, Gastropoda, Pteropoda, and Bivalvia. In P2, the most frequent taxonomic groups were Acantharia, Radiolaria, Tintinnina, Foraminifera, Copepod nauplii, Cyclopoida, Calanoida, Harpacticoida, Gastropoda, Bivalvia, and Polychaeta. Copepod nauplii dominated the surface samples, with 65% of relative abundance during both periods; Radiolaria, Tintinnina and Foraminifera dominated the deep water samples. There were differences in the abundance and biomass in response to environmental, spatial and seasonal variationsn the Tropical Water (TW-1 m) and in the South Central Atlantic Water (SCAW-250 m), These variations may related tothe rise of nutrient-rich deep waters of the SCAW to the euphotic zone, which leads to the increase of the productivity and the increase of the primary production in neritic areas, linking it to the frequent occurrence of cyclonic vortices associated with Brazil Current. In the deepest layers Antarctic Intermediate Water (AAIW-800 m), Upper Circumpolar Water (UCW-1200 m) and North Atlantic Deep Water (NADW-2300 m) it was noted a horizontal homogeneity of the microzooplankton associated with thermohaline stability. However, it is noteworthy that the high values of Radiolaria in deep water could be conditioned by the physical and chemical characteristics of the UCW. It was possible to conclude thatthe abundance and biomass of microzooplankton were higher in the surface layer and SCAW, f due to climatic fluctuations of temperature and salinity.. The temperature was the variable that most influenced the concentrations of organisms; in contrast, the low salinity fluctuations in the Campos Basin had no significant influence on the groups of microzooplankton. The data from AAIW, UCW, and NADW obtained in this work are fundamental for the understanding of the mesopelagical and bathypelagical zones in the Brazilian oceanic waters. Finally the FlowCAM used for semi-automatic analysis of samples was a useful tool for counting and obtaining information about the morphometric microzooplankton.