As human populations increase along coastal watersheds, the understanding and monitoring of Harmful Algal Blooms (or red tides) is an increasingly important issue. A consistent method for accurately detecting red tides using satellite measurements would bring tremendous societal benefits to resource managers, the scientific community and to the public as well. In the West Florida Shelf, blooms of the toxic dinoflagelate Karenia brevis are responsible for massive red tides causing fish kills, massive die-offs of marine mammals, shellfish poisoning, and acute respiratory irritation in humans. In this work, for the first time a long-term dataset (2002~2006) the MODerate Resolution Imaging Spectroradiometer (MODIS) is compared (i.e., matched-up) to an extensive data set of in situ cell counts of K. brevis; provided by the Florida Fish and Wildlife Conservation Commission's Fish and Wildlife Research Institute. The pairing of remote sensing data with near-coincident field measurements of cell abundance was successfully used to derive the basis for the development of an alternative ocean color based algorithm for detecting the optical signatures associated with blooms of K. brevis in waters of the West coast of Florida. Conclusions are geographically limited to the Central West Florida Shelf during the boreal Summer-Fall (i.e., the K. brevis blooming season). The new simpler Empirical approach is compared with other two more complicated published techniques. Their potential is verified and uncertainties involved in the identification of blooms of K. brevis are presented. The results shown here indicate that the operational NOAA method for detecting red tides in the Gulf of Mexico (Stumpf et al., 2003; Tomlinson et al., 2004) performs less accurately than the other two algorithms at identifying K. brevis blooms. The sensitivity and specificity of the Bio-optical (Cannizzaro, 2004; Cannizzaro et al., 2008) and Empirical algorithms are simultaneously maximized with an optimization procedure. The combined use of these two optimized algorithms in sequence provides another new monitoring tool with improved accuracy at detecting K. brevis of blooms. The ability of this Hybrid scheme ranges about 80% for both sensitivity and specificity; and the capability at predicting a correct red tides is 70%, and ~85% for non-blooms conditions. The spatial and temporal knowledge of K. brevis blooms can improve the direction of field monitoring to areas that should receive special attention, allowing better understanding of the red tide phenomenon by the scientific community. The relevant agencies can also develop more appropriate mitigation action plans, and public health guidance can be improved with the enhancement of sustainable costal management strategies.

The southwestern Florida shelf marine environment has often been characterized as oligotrophic, yet these waters can support large, high biomass, persistent phytoplankton blooms, including blooms of the toxin producing dinoflagellate Karenia brevis. Little is known regarding which major nutrient potentially limits primary production in these waters as both inorganic nitrogen and phosphorus concentrations are often near the limits of analytical detection and it is difficult to estimate what percentage of the dissolved organic pool is available for phytoplankton uptake. To assess the nutrient status of phytoplankton populations on the southwest Florida shelf, this project examines the particulate nutrient stoichiometry of ambient phytoplankton assemblages from 1998-2000 as part of the ECOHAB: Florida Program. Particulate C, N, P concentrations and particulate ratios display a large range of values across the West Florida Shelf (WFS). The average particulate stoichiometry is well above the classic Redfield ratio with a geometric mean of 410C:56N:1P. Frequency percentages of particulate ratio values to total sample number binned according to potential nutrient limitation indicate that 39% (C:N) of the data have values suggesting N limitation and that from 88% (N:P) to 95% (C:P) of the data have values which suggest P-limitation. It is difficult to discern whether phytoplankton biomass is truly P-limited as related to the nutrient regime on the WFS or whether detrital contributions, which can potentially be large on this shallow shelf, are skewing the N:P and C:P ratios towards higher values. Errors which could potentially be related to the different methodologies of determining C, N and P concentrations must also be considered when interpreting the particulate nutrient ratios. The data were also analyzed as subsets to determine near-shore to offshore, latitudinal, seasonal, inter-annual and K. brevis bloom versus non-bloom trends. The near-shore to offshore transect indicates decreasing concentrations of particulate C, N, P concentrations and increasing C:N, N:P, C:P ratios with increasing distance offshore. Particulate nutrient concentrations and particulate ratio values are very similar between the Tampa Bay, Sarasota and Fort Meyers transects indicating that these latitudes are not spatially distinct with regards to these variables. There does not appear to be any relationship between the particulate C, N, P concentrations or C:N, N:P, C:P ratios and rainfall as indicated by Spearman Ranking Correlation coefficients. However, there does appear to be monthly trends across the shelf where peak particulate nutrient concentrations and particulate ratio values occur during the spring, summer and fall. The average particulate nutrient concentrations and ratios differ for each year as well as each K. brevis bloom which occurred during the study period. In summary, the particulate C, N, P concentrations and particulate nutrient ratios vary both spatially and temporally on the WFS and are potentially related to the flexibility of phytoplankton uptake kinetics in response to the varying nutrient regimes of the WFS.

A coupled, three-dimensional, time-dependent numerical model of water circulation, spectral light, plankton dynamics, nutrient/CDOM loadings, and zooplankton grazing provided an assessment of the factors affecting the growth and maintenance of red tides on the west Florida shelf (WFS). The coupled biophysical model consisted of state variable quantities for temperature, salinity, horizontal/vertical velocity components, turbulent diffusion, spectral light, colored dissolved organic matter (CDOM), dissolved organic and inorganic carbon, particulate silica, four dissolved inorganic nutrient pools (nitrate, ammonium, phosphate, and silicate), and four phytoplankton groups (diatoms, microflagellates, non-toxic dinoflagellates, and the red tide organism Karenia brevis). The model also included a complex grazing scheme that utilized thirteen different zooplankton groups to explore the effects of selective herbivory, feeding periodicity, diel vertical migration, fecal pellet egestion, and ammonium/phosphate excretion within a diverse zooplankton community. Over the shelf and slope of the eastern Gulf of Mexico, from the Mississippi River delta to the Florida Keys, four cases of the model were run during August -- November to explore the dynamics of red tide maintenance with respect to: (1) no refuge from grazing for K. brevis; (2) grazer avoidance of K. brevis during CDOM shading; (3) grazer avoidance of K. brevis in Case II waters; and (4) increased grazing stress on K. brevis competitors. NEGOM and ECOHAB data sets during July -- November 1999 were used to establish the initial/boundary conditions and provided validation data for the coupled model as well. Model results indicate that the red tide of 5.9 x 10 6 cells L-1 witnessed offshore Sarasota, Florida on 07 October 1999 was initiated by an inoculum of K. brevis observed in near-bottom waters above the 30 m isobath offshore Sarasota on 31 August 1999. Flowfields measured at moored ADCPs, observations from AVHRR satellite imagery, and west Florida shelf circulation models indicate that conditions of coastal upwelling existed during the period of bloom development, such that the K. brevis inoculum was delivered to the coast in the bottom Ekman layer. As a shade-adapted species capable of vertical migration, K. brevis cells aggregated near the bottom in order to escape photo-inhibitive light intensities in the overlying water column during the day and harvested the recycled nitrogen excreted by zooplankton grazers. This concomitant relaxation of light inhibition and nitrogen-limitation ultimately led to the growth and maintenance of the red tide, constrained in near-bottom waters during much of the day and preferentially advected inshore as a result of coastal upwelling. As K. brevis was advected inshore, self-shading, CDOM, and suspended inorganic particulates all contributed to the prevention of photo-inhibitive light intensities that, in combination with the excretion of recycled ammonium, ultimately led to the maintenance of a significant red tide at the coast.

Harmful algal blooms (HABs) of the brevetoxin-producing dinoflagellate Karenia brevis occur periodically along the central west coast of Florida. Mass mortalities of marine birds have long been associated with these blooms, yet there is little data documenting the accumulation of brevetoxins in the tissues of birds and their prey items. An intense HAB event impacted the region from Tampa Bay to Charlotte Harbor during most of 2005. More than one hundred marine birds, representing twenty three species, were collected during this bloom. All birds sampled were found dead or had died within 24 hours of admittance to local wildlife rehabilitation centers. In order to determine if fish were vectors for brevetoxin ingestion, the stomach contents of all birds were examined and any recovered fish were identified to the extent possible. The gastrointestinal tissues and contents from all avian samples were analyzed for brevetoxin levels, with results ranging from Shorebirds and gulls may also be exposed to brevetoxins via scavenging of red tide-killed fish deposited on beaches during blooms. Samples from scavenged fish were found to have brevetoxin levels ranging from 31 to 95,753 ng PbTx per gram tissue.

Submitted by Luiza Helena Bueno da Silva null (bueno.luizah@gmail.com) on 2017-10-02T13:04:18Z No. of bitstreams: 1 Dissertação Luiza.pdf: 2492240 bytes, checksum: 760cbfcbde8b0aca71cdc95bd132254b (MD5) / Approved for entry into archive by Monique Sasaki (sayumi_sasaki@hotmail.com) on 2017-10-02T18:31:27Z (GMT) No. of bitstreams: 1 silva_lhb_me_rcla.pdf: 2492240 bytes, checksum: 760cbfcbde8b0aca71cdc95bd132254b (MD5) / Made available in DSpace on 2017-10-02T18:31:27Z (GMT). No. of bitstreams: 1 silva_lhb_me_rcla.pdf: 2492240 bytes, checksum: 760cbfcbde8b0aca71cdc95bd132254b (MD5) Previous issue date: 2017-08-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A presença de cadáveres no interior dos ninhos dos insetos sociais pode propiciar a contaminação com patógenos e prejudicar a integridade da colônia. O comportamento higiênico frente a cadáveres é imprescindível na manutenção da homeostase do ninho, mas em cupins ainda é pouco conhecido. Assim, o objetivo do presente trabalho foi estudar o comportamento higiênico diante de cadáveres de diferentes origens em três espécies de cupins com distintos tipos de nidificação. O cupim de madeira seca Cryptotermes brevis vive no interior do próprio alimento, o cupim Cornitermes cumulans constrói ninhos epígeos e o cupim Coptotermes gestroi é subterrâneo e constrói ninhos polidômicos. Diferentes bioensaios foram realizados com colônias de C. brevis e C. cumulans, nas quais foram introduzidos cadáveres de operários da mesma colônia, de outra colônia e de outra espécie. Adicionalmente, bioensaios foram realizados com subcolônias de C. gestroi (grupos de 300 operários e 15 soldados), nas quais foram inseridos cadáveres de operários e soldados da mesma colônia, de outra colônia e de outra espécie mortos recentemente e há 24 horas. Os bioensaios foram filmados e as respostas comportamentais dos indivíduos próximos aos cadáveres foram registradas. O repertório comportamental de C. brevis diante de cadáveres incluiu antenação, agonismo, alarme, recuo, grooming e consumo dos mesmos. Ninfas e falsos-operários de C. brevis consumiram os cadáveres, independentemente, da origem dos mesmos, mas evitaram a ingestão das partes quitinosas da cabeça. Nesta espécie, o consumo de cadáveres, além de desempenhar função higiênica, parece ser uma estratégia de aquisição de nitrogênio e água. O casal real das colônias de C. brevis observadas não participou do comportamento higiênico. O repertório comportamental de C. cumulans incluiu diferentes atividades, tais como: antenação, agonismo, alarme, recuo, grooming, deposição de material fecal, enterro com solo e transporte do cadáver para o ninho. Nesta espécie, corpos de origem interespecífica e intercolonial foram cobertos com solo após grooming. Corpos de companheiros de ninho foram enterrados (60% das repetições), carregados para o ninho (30%) ou ignorados após serem submetidos ao grooming (10%), o que indica uma plasticidade comportamental em C. cumulans. Em subcolônias de C. gestroi o repertório comportamental incluiu atividades como: antenação, recuo, grooming, agonismo, alarme, deposição de solo e consumo integral ou parcial do cadáver. Soldados de grupos de C. gestroi não consumiram ou enterraram cadáveres. Corpos de operários de diferentes origens foram discriminados por subcolônias de C. gestroi, o que não aconteceu com cadáveres de soldados com tempo de post-mortem maior. Cadáveres de cupins de outras espécies e de outras colônias foram enterrados após grooming por grupos de C. gestroi, porém companheiros de ninho foram preferencialmente canibalizados. O caráter higiênico do comportamento de grooming em cadáveres juntamente com o isolamento físico por meio do enterro dos mesmos com solo colabora para a não dispersão de patógenos entre membros da colônia. Os resultados do presente trabalho mostram que os cupins realizam o comportamento higiênico em cadáveres de térmitas de diferentes origens, contudo este processo foi mais simples em C. brevis, cupim com nidificação do tipo “uma peça”. Nos cupins “múltiplas peças” tais como C. gestroi e C. cumulans, o comportamento higiênico foi mais complexo, com recrutamento de indivíduos, mostrando que o manejo de cadáveres é essencial para o desenvolvimento e homeostase destes ninhos. / The presence of dead individuals inside nests of social insects can be a risk of contamination with pathogens and damage the integrity of the colony. The hygienic behavior towards corpses is essential in maintaining nest homeostasis, but in termites it is still little known. Thus, the objective of the present study was to observe the hygienic behavior towards corpses from different origins in three species of termites with distinct types of nesting. The drywood termite Cryptotermes brevis lives inside its own food, Cornitermes cumulans builds mound nests and Coptotermes gestroi is a subterranean termite that builds polydomous nests. Different bioassays were performed with colonies of C. brevis and C. cumulans, in which corpses of workers of termites from the same colony, from another colony and from another species were introduced. Additionally, bioassays of subcolonies of C.gestroi were performed in which corpses of workers and soldiers from the same colony, from another colony and from another species freshly dead and dead for 24 hours were introduced. The bioassays were recorded and the behavioral responses from the different species were registered. The results showed that the behavioral repertoire of C. brevis towards corpses included: antenation, aggression, alarm, retreat, grooming and consumption. Nymphs and pseudergates of C. brevis consumed the corpses independently of their origin, but they avoided the chitinous parts of the head. In this species, consumption of dead individuals, besides performing a hygienic function, seems to be a strategy of nitrogen and water acquisition. The royal couple of C. brevis colonies observed did not participate of the hygienic behavior. The behavioral repertoire of C. cumulans towards corpses included activities, such as: antenation, agression, alarm, retreat, grooming, deposition of fecal material, entombment and transport of corpse to the nest. In this species, inter-specific and inter-colonial corpses were covered with soil after being groomed. Nestmate corpses were entombed (60% of replications), transported to the nest (30%) or ignored after being submitted to grooming (10%), which indicates the behavioral plasticity of the C. cumulans species. In subcolonies of C. gestroi the behavioral repertoire included activities such as: antenation, retreat, grooming, aggression, alarm, deposition of soil, integral or partial consumption of corpses. Soldiers of C. gestroi subcolonies never consumed or buried corpses. However, corpses of workers from different origins were discriminated by C. gestroi subcolonies, which did not occurred with corpses of soldiers with longer period of post-mortem. Termite corpses from another species or from another colony were buried after being groomed by C. gestroi groups, but nestmate corpses were preferably cannibalized. The hygienic character of grooming behavior in corpses along with the physical isolation through entombment with soil contributes to the non-dispersion of pathogens among colony members. The results of the present study indicate that termites perform hygienic behavior in termite corpses from different origins, however, this process was less elaborate in C. brevis, one-piece nesting termite. In multiple-pieces nesting termites, such as C. gestroi and C. cumulans, the hygienic behavior was more complex, with recruitment of individuals, showing that the management of corpses is essential for the development and homeostasis of the termite nests.

Algae are important to marine and fresh-water ecosystems. However, some species of algae are harmful or even toxic. They can consume oxygen or block sunlight that is essential for other organisms to live. Indeed, some algae blooms can produce toxins that damage the health of the environment, plants, animals, and humans. Harmful algal blooms (HABs) which are often more green, brown, or dark-colored than red have spread along the coastlines and in the surface waters of the United States. Therefore, scientists are making great efforts to study HABs in order to maintain human and ecosystem health. Karenia brevis, the major harmful algal bloom dinoflagellate of the Gulf of Mexico, plays a destructive role in the region. Karenia brevis, responsible for Florida red tide, is the principle HAB dinoflagellate in the Gulf of Mexico. K. brevis blooms can produce brevetoxin: ladder-shaped polyether (LSP) compounds, which can lead to adverse human health effects, like reduced respiratory function through inhalation exposure, or neurotoxic shellfish poisoning through consumption of contaminated shellfish. The poisoning has been attributed to their affinity for voltage-sensitive sodium ion channels causing channel opening and depolarization of excitable cell membranes. Conservative estimate suggests that the economic impact from all harmful algal bloom events in the United States is at least $82 million/year. The public health costs occupy $37 million alone. The study presented herein utilized fluorescent and photolabile brevetoxin probes to demonstrate that brevetoxin localizes in the chloroplast of K. brevis where it binds to light harvest complex II (LHC II) and thioredoxin (Trx). It had been discovered that the TrxR/Trx system was inhibited by brevetoxin-2 (PbTx-2) with an IC50 of 25 µM. The mechanism of the inhibition was discussed in this work. The research also revealed that the K. brevis high-toxic and low-toxic strains have a significant difference in their ability, not only to produce brevetoxin, but also to perform NPQ and in the production of ROS. I compared and contrasted various metabolic and biochemical parameters in two strains of K. brevis which had a ten-fold difference in toxin content. The work could shed light on the physiological role that brevetoxin fills for K. brevis and may contribute to understanding the effect of ladder-shaped polyether compounds on both marine animals and exposed humans and shall inform improved treatments for brevetoxicosis.

The objective of this research is to evaluate a coastal prediction system under various real world scenarios to test the efficacy of the system as a management tool in Tampa Bay. The prediction system, comprised of a three-dimensional numerical circulation model and a Lagrangian based particle tracking model, simulates oceanographic scenarios in the bay for past (hindcast), present (nowcast) and future (forecast) time frames. Instantaneous velocity output from the numerical circulation model drives the movement of particles, each representing a fraction of the total material, within the model grid cells. This work introduces a probability calculation that allows for rapid analysis of bay-wide particle transport. At every internal time step a ratio between the number of particles in each individual model grid cell to the total number of particles in the entire model domain is calculated. These ratios, herein called transport quotients, are used to construct probability maps showing locations in Tampa Bay most likely to be impacted by the contaminant. The coastal prediction system is first evaluated using dimensionless particles during an anhydrous ammonia spill. In subsequent studies biological and chemical characteristics are incorporated into the transport quotient calculations when constructing probability maps. A salinity tolerance is placed on particles representing Karenia brevis during hindcast simulations of a harmful algal bloom in the bay. Photobleaching rates are incorporated into probability maps constructed from hindcast simulations of seasonal colored dissolved organic matter (CDOM) transport. The coastal prediction system is made more robust with the inclusion of biological parameters overlaid on top of the circulation dynamics. The system successfully describes the basic physical mechanisms underlying the transport of contaminants in the bay under various real world scenarios. The calculation of transport quotients during the simulations in order to develop probability maps is a novel concept when simulating particle transport but one which can be used in real-time to support the management decisions of environmental agencies in the bay area.

Muscle fatigue is an intrinsic myoprotective process that prevents damaging ATP depletion during intense or prolonged exercise by limiting ATP demand when ATP production becomes insufficient. One mechanism of fatigue involves a reduction in membrane excitability with the opening of ATP-sensitive K+ (KATP) and ClC-1 Cl- channels, resulting in submaximal sarcoplasmic reticulum Ca2+ release and reduced force generation, but the intracellular signalling pathways for this process is unknown. As a first step toward understanding this process, the objective of this study was to test the hypothesis that adenosine receptors (ARs) and AMPK trigger fatigue when a metabolic stress occurs during muscular activity. Compared to control conditions, a pan-activation of ARs with 10 µM adenosine and NECA initially reduced the fatigue rate during the first 60 s of a 3 min fatigue bout triggered with 1 tetanic contraction every s. An activation of the A1 adenosine receptor (A1R) with 10 and 20 µM ENBA resulted in faster rate of fatigue; an effect blocked by 5 µM DPCPX, an A1R antagonist. At 10 and 20 µM, adenosine, NECA, and ENBA activated AMPK via an increased in T172 phosphorylation. At 10 µM, MK8722, an AMPK agonist, initially caused a reduction in fatigue rate during the first 60 s followed by an increased fatigue rate during the last 2 min of the fatigue bout. Co-activation of ARs and AMPK did not give rise to either an additive or synergistic effect. FDB from AMPK α1-/- and α2-/- mice had faster fatigue rate and greater increased in unstimulated force compared to FDB from AMPK α1+/+ and α2+/+ mice. It is suggested that ARs and AMPK play a role in the mechanism of fatigue when a metabolic stress develops during muscle activity.

An estimated 23,000 ankle injuries occur every day in the U.S. Ankle sprains account for 85% of all ankle injuries and inversion ankle sprains account for 85% of all ankle sprains. There is growing evidence that suggests gender and fatigue may increase the risk for inversion ankle sprains. Investigating the effects of fatigue and gender on peroneal reflex response after ankle inversion may help explain the differences in sprain rates with fatigue and gender. Therefore, the purpose of this study was to investigate the effects of fatigue and gender on peroneus brevis and peroneus longus reflexes after ankle inversion. A "trap-door" platform was used to elicit peroneal reflexes from sixteen males and fifteen females by suddenly inverting the ankle to 20°. Five unfatigued peroneal reflex measurements were performed before and after a fatigue protocol that attempted to fatigue the ankle evertors over 12 minutes to 75% of the unfatigued MVC torque. Results showed that reflex delay was not affected by fatigue, gender, or their interaction. PL reflex amplitude was not affected by fatigue or gender but was affected by their interaction. Results showed that PL reflex amplitude decreased by 11.3% in males and increased 22.1% in females with fatigue. A secondary analysis attempted to rule out extraneous factors that could have contributed to the differences in reflex response, but no experimental explanations were found. The differences in PL reflex amplitude were attributed to biomechanical, physiological, and anatomical differences between males and females. / Master of Science

Lulas da família Loliginidae são recursos pesqueiros em crescente importância no ecossistema marinho da Plataforma Continental Sudeste (PCSE) do Brasil. No entanto, informações sobre a distribuição dos estágios iniciais do seu ciclo de vida são bastante escassas. Com base em amostras de plâncton coletadas por 11 cruzeiros oceanográficos pretéritos do Instituto Oceanográfico da USP entre 1991 e 2005, o presente estudo teve como objetivo a identificação da ocorrência de paralarvas de Loliginidae na região entre o Cabo de São Tomé (RJ) e Cananéia (SP). Das 644 amostras analisadas, foram encontradas 246 paralarvas, sendo 121 identificadas em nível de espécie (Doryteuthis sanpaulensis n=75, Doryteuthis plei n=39, Lolliguncula brevis n=6 e Pickfordiateuthis pulchella, n=1). Os padrões de distribuição da Família em relação aos processos oceanográficos foram identificados a partir de mapas de distribuição horizontal e vertical de abundância, temperatura e salinidade. Modelos Lineares Generalizados (GLMs) foram utilizados para detectar os fatores que explicariam a ocorrência e a abundância de Loliginidae, os quais indicaram que a profundidade e a temperatura superficial do mar são as principais variáveis explanatórias. Uma Análise de Redundância (RDA) evidenciou os principais padrões de distribuição observados das três principais espécies de Loliginidae em relação às variáveis oceanográficas. D. sanpaulensis predominou na região norte da área de estudo, associada a águas frias e a eventos de ressurgência. D. plei ocorreu principalmente na região sul da área e em águas mais quentes. L. brevis foi encontrada apenas na região estuarina de Santos, em águas rasas e menos salinas. Os resultados obtidos representam uma contribuição relevante ao conhecimento sobre a Oceanografia Pesqueira das lulas no ecossistema marinho regional. / Loliginid squids are fisheries resources of increasing importance in the shelf ecosystem of Southeastern Brazil. Therefore, information about distribution of the early stages of their life cycle is scarce. Based on plankton samples collected by eleven historical oceanographic surveys cruises of the University of São Paulo\'s Oceanographic Institute between 1991 and 2005, the present study aimed identification of the occurrence of Loliginidae paralarvae in the region between Cabo de São Tomé (22ºS) and Cananéia (25ºS). From 664 samples analyzed, 246 paralarvae were found, being 121 identified to the species level, (Doryteuthis sanpaulensis n=75, Doryteuthis plei n=39,, Lolliguncula brevis n=6 and Pickfordiateuthis pulchella, n=1). The distributional patterns of Loliginidae in relation to oceanographic processes were identified by using horizontal and vertical maps of abundance, temperature and salinity. Generalized Linear Models (GLMs) were used to detect the factors that explain Loliginidae occurrence and abundance, which indicated that depth and sea surface temperature, were major explanatory variables. A Redundancy Analyses (RDA) showed the main observed distribution patterns of the three species of Loliginidae in relation to oceanographic variables. D. sanpaulensis occurred in the northern region associated to cold waters and upwelling events. D. plei occurred mainly in the southern region of the study area and in warmer waters.L. brevis was found in the estuarine region of Santos, in shallow and low salinity waters. The obtained results represent a relevant contribution to squids Fisheries Oceanography in the regional marine ecosystem.