Northeast Coast Of Brazil Research Articles

Pseudoceros astrorum, a new species of Polycladida (Cotylea, Pseudocerotidae) from Northeastern Brazil.

Pseudoceros astrorum n. sp. is characterized by a smooth dorsal surface with a brown ground colour, and with net-like pattern of small black granules, white spots of different sizes uniformly distributed, a thin black sub-marginal band, and a white marginal rim. The pseudotentacles are dark brown with white tips and the anterior margin and cerebral region is devoid of pigmentation. The male system is characterised by conspicuous spermiducal bulbs, a conical curved penis stylet, and the sucker lies more or less posterior. With this contribution, the number of known species from Brazil is now 72, and has created new interest in the lesser-known polyclad fauna from the northeast coast of Brazil.

First record of Trachycaris restricta (A. Milne-Edwards, 1878) (Crustacea, Hippolytidae) from the State of Sergipe, northeast Brazil: Filling distribution gaps

This paper presents the first record of Trachycaris restricta (A. Milne-Edwards, 1878) from the State of Sergipe, filling a gap of occurrence of this species in the Brazilian northeast coast and compiles previous reports of this species from Brazil. The analyzed specimens were associated with algae and captured through daytime fishery hauls in two sampling stations at 30 m depth in March 2000.

First record of Trachycaris restricta (A. Milne-Edwards, 1878) (Crustacea, Hippolytidae) from the State of Sergipe, northeast Brazil: Filling distribution gaps

This paper presents the first record of Trachycaris restricta (A. Milne-Edwards, 1878) from the State of Sergipe, filling a gap of occurrence of this species in the Brazilian northeast coast and compiles previous reports of this species from Brazil. The analyzed specimens were associated with algae and captured through daytime fishery hauls in two sampling stations at 30 m depth in March 2000.

The past and present of an estuarine-resident fish, the "four-eyed fish" Anableps anableps (Cyprinodontiformes, Anablepidae), revealed by mtDNA sequences.

Historical events, such as changes in sea level during the Pleistocene glacial cycles, had a strong impact on coastal habitats, limiting connectivity and promoting the genetic divergence of various species. In this study, we evaluated the influence of climate oscillations and the possibility of estuary function as a barrier to gene flow among populations of the four-eyed fish, Anableps anableps. This species is fully estuarine-resident, has internal fertilization, is viviparous and does not migrate across long distances. These features make the four-eyed fish an excellent model for the study of evolutionary processes related to genetic differentiation of species and populations in estuaries. The evolutionary history of A. anableps was inferred from phylogeographic and population analyses using sequences of the mitochondrial DNA Control Region of 13 populations distributed in the Amazon and Northeast Coast of Brazil from Calcoene (Amapa) to Parnaiba (Piaui). The 83 retrieved haplotypes show a pattern of four distinct mitochondrial lineages, with up to 3.4% nucleotide divergence among them. The evolutionary reconstruction suggests that these lineages diverged recently in the late Pleistocene/early Holocene after the Atlantic Ocean reaching current levels. Analysis of variability, neutrality and the genetic expansion pattern revealed that the lineages have distinct characteristics, which were shaped by the different geomorphological features of coastal regions combined with sea level oscillations over a very long period of time. Only few neighboring populations show a discreet gene flow. This study may also be helpful for designing new experiments to better understand the geomorphological evolutionary history of the estuaries of the Amazon and the Northeast Coast of Brazil using estuarine-resident species as a model.

Estuarine macrofauna responses to continuous in situ nutrient addition on a tropical mudflat

A field experiment to assess the effects of continuous nutrient addition on the macrobenthic community was carried out on an estuarine mudflat on the northeast coast of Brazil. The experiment began on 5 October 2005 and ended on 8 February 2006. Macrofauna was compared at approximately four-week intervals in triplicate plots with three levels (Control – C, Low Dose – LD and High Dose – HD) of weekly fertilizer additions for 17weeks. Inorganic fertilizer (N–P–K) was applied on nine randomly defined quadrangular plots (4m2 each). All measurements were calculated from species abundances. Multivariate analyses as well as the univariate indices (richness, abundance and Shannon–Wiener index) showed statistically significant differences between the enriched and control areas during the period of the experiment. The expected gradual response based on the succession model of Pearson and Rosenberg was not observed. The nutrient doses used were high enough to cause severe decreases in abundance, richness and evenness, and an increase in dominance.

Surface observation of a birth of a humpback whale (Megaptera novaeangliae) on the northeast coast of Brazil

Surface observation of a birth of a humpback whale (Megaptera novaeangliae) on the northeast coast of Brazil

Morphological Analysis of Lymph Nodes in Odontocetes From North and Northeast Coast of Brazil

The morphology and location of lymph nodes from seven species of Odontocetes, of both sexes and different age groups, were described. All animals were derived from stranding events along the North and Northeastern coasts of Brazil. After the identification of lymph nodes in situ, tissue samples were analyzed for light and electron microscopy. Vascular volume density (VVD) and vascular length density (VLD) were evaluated in the mesenteric lymph nodes. Lymph nodes occurred as solitary nodules or in groups, varying in shape and size. In addition to using the nomenclature recommended by Nomina Anatomica Veterinaria, new nomenclatures were suggested based on the lymph nodes topography. Lymph nodes were covered by a highly vascularized and innervated capsule of dense connective tissue, below which muscle fibers were observed, inconsistently, in all studied species. There was no difference in VLD among different age groups. However, VVD was higher in adults. Lymph nodes parenchyma was divided into an outer cortex, containing lymph nodules and germinal centers; a paracortical region, transition zone with dense lymphoid tissue; and an inner medulla, composed of small irregular cords of lymphatic tissue, blood vessels, and diffuse lymphoid tissue. Abundant collagen fibers were observed around arteries and arterioles. Germinal centers were more evident and developed in calves and young animals, being more discrete and sparse in adults. The morphology of lymph nodes in Odontocetes was typical of that observed in other terrestrial mammals. However, new groups of lymph nodes were described for seven species occurring in the Brazilian coast.

Genetic multipartitions based on D-Loop sequences and chromosomal patterns in brown chromis, Chromis multilineata (Pomacentridae), in the Western Atlantic.

Connectivity levels among Brazilian reef fish fauna populations have attracted growing interest, mainly between mainland shores and oceanic islands. The Pomacentridae, whose phylogeographic patterns are largely unknown in the Atlantic, are a family of dominant fish in reef regions. We present data on the variability and population structure of damselfish Chromis multilineata in different areas along the northeast coast of Brazil and in the waters around the oceanic islands of Fernando de Noronha (FNA) and Saint Peter and Saint Paul Archipelago (SPSPA) through analysis of the HVR1 mtDNA sequence of the control region. The remote SPSPA exhibits the highest level of genetic divergence among populations. Conventional and molecular cytogenetic analysis showed similar karyotype patterns (2n = 48 acrocentrics) between these insular areas. Our estimates reveal three genetically different population groups of C. multilineata on the Brazilian coast. The level of genetic structure is higher than previous data suggested, indicating complex panel of interactions between the oceanic island and coastal populations of Brazil.

Thalassophryne nattereri fish venom: from the envenoming to the understanding of the immune system.

Thalassophryne nattereri (niquim) is a venomous fish found off North and Northeast coast of Brazil, where it is known by the severity of the accidents involving humans. This review article is divided into four topics. The first one provides a brief description of the animal biology and its distribution off Brazilian coastal waters, the venom apparatus, signs and symptoms observed in envenomated humans and also describes envenomation in mice. The second topic describes the use of modern genetic approach and mass spectrometry for identification of highly expressed genes in its venom glands and the sequence of major toxins. The third chapter offers a detailed study of tissue injury induced by the venom and reveals the role of toxins that impair inflammation reduction. Finally, the fourth section expands the understanding of many extrinsic and intrinsic essential factors in maintaining survival of memory B cell compartment. Our results demonstrate the wide possibilities for research in the area of toxinology, also the necessity of interconnection among biochemistry, pharmacology and immunology areas for the expansion of knowledge and for generation of innovation.

Modeling Subsurface Gas Release in Tropical and Shallow Waters: Comparison with Field Experiments off Brazil's Northeast Coast

ABSTRACT Despite the fast growth of underwater oil and gas exploration in low latitude regions, very few experimental data acquisition and modeling studies involving gas release in tropical and shallow waters are found in literature. In this article, a dataset of geophysical and gas release measurements obtained from an in situ experiment conducted off the northeastern Brazilian coast are used as a baseline for evaluating the GASOCEAN blowout model. Hydrological and hydrodynamic data were collected for distinct seafloor gas plume releases (3000 to 9000 L/hr) during neap/spring tides of summer/dry and winter/wet periods. Simulation results indicate that the gas plume is horizontally displaced by the horizontal current as it rises through seawater column. The extreme situation provided a critical radius (maximum horizontal displacement) from the gas release source of 35.2 m. The comparison between the measured and the calculated data showed that the model satisfactorily represented the main features of the gas release, such as the displacement (11.6–35.2 m), diameter (1.2–2.8 m), and ascending time (1.1–1.6 min) of the plumes. Although the mean plume widths have the same order of magnitude between the measurements and the calculations, improvements may enhance the model's performance during the earlier plume development.

The effect of nutrient-rich effluents from shrimp farming on mangrove soil carbon storage and geochemistry under semi-arid climate conditions in northern Brazil

A semi-arid mangrove estuary system in the northeast Brazilian coast (Ceará state) was selected for this study to (i) evaluate the impact of shrimp farm nutrient-rich wastewater effluents on the soil geochemistry and organic carbon (OC) storage and (ii) estimate the total amount of OC stored in mangrove soils (0–40cm). Wastewater-affected mangrove forests were referred to as WAM and undisturbed areas as Non-WAM. Redox conditions and OC content were statistically correlated (P<0.05) with seasonality and type of land use (WAM vs. Non-WAM). Eh values were from anoxic to oxic conditions in the wet season (from −5 to 68mV in WAM and from <40 to >400mV in Non-WAM soils) and significantly higher (from 66 to 411mV) in the dry season (P<0.01). OC contents (0–40cm soil depth) were significantly higher (P<0.01) in the wet season than the dry season, and higher in Non-WAM soils than in WAM soils (values of 8.1 and 6.7kgm−2 in the wet and dry seasons, respectively, for Non-WAM, and values of 3.8 and 2.9kgm−2 in the wet and dry seasons, respectively, for WAM soils; P<0.01). Iron partitioning was significantly dependent (P<0.05) on type of land use, with a smaller degree of pyritization and lower Fe-pyrite presence in WAM soils compared to Non-WAM soils. Basal respiration of soil sediments was significantly influenced (P<0.01) by type of land use with highest CO2 flux rates measured in the WAM soils (mean values of 0.20mgCO2h−1–g−1 C vs. 0.04mgCO2h−1–g−1 C). The OC storage reduction in WAM soils was potentially caused (i) by an increase in microbial activity induced by loading of nutrient-rich effluents and (ii) by an increase of strong electron acceptors [e.g., NO3−] that promote a decrease in pyrite concentration and hence a reduction in soil OC burial. The current estimated OC stored in mangrove soils (0–40cm) in the state of Ceará is approximately 1milliont.

First record of Chaetacanthus magnificus (Polychaeta: Polynoidae) from the northeast coast of Brazil, with an overview of its taxonomic history

Polynoidae is a diverse group of polychaetes known as scale-worms, found in different marine regions. However this rich family is little studied in Brazil, especially along the northeastern coast of the country. We report Chaetacanthus magnificus, a first record for the northeastern coast of Brazil, establish this species as valid, differentiating it from other synonyms found in several studies which report polychaetes in Central and South America. The polychaetes found by Project Algae of Paraíba are in the collection of Laboratory of Marine Invertebrates Paulo Young, Universidade Federal da Paraíba, Brazil.KEY WORDSPolychaetes, Polynoidae, scale-worm, South America, new record

Breve revisão sobre a evolução histórica da atividade salineira no estado do Rio Grande do Norte (Brasil)

A presente pesquisa se trata de uma tentativa de elencar alguns dos principais eventos históricos que marcaram a evolução da atividade salineira a partir da colonização da América portuguesa, com enfoque direcionado ao espaço que hoje corresponde ao Estado do Rio Grande do Norte. Essa atividade teve início com a descoberta e exploração das reservas naturais e a posterior produção de sal marinho nas salinas artesanais. Ao longo do tempo, a atividade salineira passou a impulsionar o desenvolvimento de outras atividades a ela relacionadas, configurando-se como uma das principais atividades econômicas desenvolvidas nas margens das desembocaduras dos principais rios da Capitania do Rio Grande (do Norte). Com o aumento da demanda nacional (séc. XVIII), várias salinas de pequeno porte passaram a ser construídas ao longo do litoral nordeste do Brasil. Todavia, o advento, no Brasil, da política desenvolvimentista baseada na industrialização (segunda metade do século XX) refletiu profundamente nesta atividade, com a implementação de uma indústria salineira de grande porte, com processos de produção e de engenharia baseados no modelo dos Estados Unidos, com a modernização e dinamização de setores industriais para atender às elevadas demandas da indústria química em expansão no país.

Evaluation of the stocks of Hypnea musciformis (rhodophyta: gigartinales) on two beaches in Bahia, Brazil

Hypnea musciformis occurs widely in the northeast coast of Brazil, and it is one of the most important natural sources of k-carrageenan, which is used in food and cosmetic industries. Despite its potential for exploitation little is known about its ecology. The aim of this study was to investigate the biology and ecology of H. musciformis in Brazil through analyses of biomass stock and accompanying flora. Two populations of H. musciformis were analyzed: those on the beaches of Stella Maris and Itacimirim (Bahia, Brazil). Eight samplings were conducted between 2007 and 2009 during the dry and rainy seasons. The algae were sampled along transects (20 m) using quadrats (0.04 m²) in three different hydrodynamic regions of the reefs (TP, PRR and FRR). The t-Test, Dunn's Test and parametric and nonparametric ANOVA were used for statistical analyses. 17 host species and 41 associated species were identified. The highest biomass stock was observed during the dry season. On Stella Maris, the region with the highest biomass stock was FRR; on Itacimirim, TP had the highest biomass value. This study permits the assumption that seasonality, microhabitat, hydrodynamic and micro scale factors contribute to variation in biomass stock in H. musciformis populations.

Plastic pollution risks in an estuarine conservation unit

ABSTRACT Ivar do Sul, J.A. and Costa, M.F. Plastic pollution risks in an estuarine conservation unit. Plastics enter the marine environment mostly from land-based sources, often via estuaries. However, studies related to plastic debris pollution remain rare within these environments. An estuarine beach comprised within a Marine Conservation Unit (MCU) in the Northeast coast of Brazil was studied during one year regarding plastic pollution. Petroleum derived products were >95% of all items, as commonly reported for other coastal and marine habitats. Monthly totals of marine debris presented an average of 10.8±1.63 items.100m−2, much lower than reported in the literature for other estuarine beaches. Three main sources were identified: fisheries, local users and human settlements along the river basin. The most frequent (56%) size category was 11–100cm2, but fragmented items alone were 83% of observed items. The main impact on the estuarine and visiting biota expected is the ingestion of plastic items and fr...

Threats to sea turtle populations in the Western Atlantic: poaching and mortality in small-scale fishery gears

ABSTRACT Guebert, F.M., Barletta, M. and Costa, M.F., 2013. Threats to sea turtles in the Western Atlantic: poaching and mortality in small-scale fishery gears. Interactions between small-scale fishery activities and sea turtles were investigated in coastal fishers' population of the South and Northeast Brazilian coast, Western Atlantic. Data were collected using semi-structured questionnaires (N=418). The presence of four sea turtle species was confirmed in the studied areas: Chelonia mydas, Caretta caretta, Eretmochelys imbricata and Dermochelys coriacea. Adults are commonly seen in the water, and nesting females and hatchlings on beaches, especially at the Northeast region. The presence of the three most easily distinguishable ontogenetic phases (hatchlings, juveniles and adults) confirms the importance of the estuaries and adjacent areas for sea turtles feeding, gathering, nesting, growing and resting grounds. Fishing was considered the most important threat to sea turtles (77%). Gillnets with small m...

Pronounced Particularity: A Comparison of Governance Structures on Lord Howe Island and Fernando de Noronha

This paper compares and contrasts the management systems and governance structures of two island sites with national and international World Heritage recognition: Lord Howe Island (off the mid-east coast of Australia) and Fernando de Noronha (off the north-east coast of Brazil). Using historical and contemporary references, the paper explores the manner in which two distinct approaches to governance are implicated in the daily living of community members, and considers their socioeconomic activities. We use the case of tourism and World Heritage management as examples of the complexities involved in the different forms of governance structures adopted by these two small oceanic islands: similar in nature and official status, but significantly different when the outcomes of their governance practices are analysed. In the final part of the paper, we suggest mechanisms and approaches that can promote sustainable local engagement with island issues.

Survey of the manatee´s (Trichechus manatus, Linnaeus, 1758) distribution, occurrence and status of conservation in the northeast coast of Brazil

In the early 80's the first survey was conducted on the distribution of marine manatees in Brazil, which pointed out the north and northeast coasts as areas of occurrence, and recorded its disappearance in the Espirito Santo and Bahia States. Considering the absence of recent data, this study aimed to update existing information on the distribution and areas of occurrence of the Trichechus manatus in the Northeastern coast of Brazil, as well as evaluating the conservation status of species and to support the work of preserving this sirenian. The survey was conducted during the years 1990 and 1991 from the coast of Sergipe to Piaui. A questionnaire with eight questions was used being applied to fishermen. When we confirm the importance of location for the occurrence of the manatee, nautical raids were carried out in order to spot the animals, environments and recognition of the major threats to the species. The displacements along the study area were performed by a 4x4 Toyota Bandeirante, called "Igarakue." After 16 months of activities, the mobile unit "Igarakue" had travelled almost all the villages and coastal regions of seven northeastern states (Sergipe, Alagoas, Pernambuco, Paraiba, Rio Grande do Norte, Ceara and Piaui), with 552 interviews conducted in 199 locations . Worryingly it was observed the disappearance of the species in the Sergipe State, the isolation of populations present in the Alagoas State and the presence of discontinuous areas along the distribution in other states. The estimated abundance for the study area, with the minimum number of 117 specimens and a maximum of 242 specimens, where data showed a decrease in the total number of manatees sighted in recent decades. The marine environment has been indicated as the site of highest number of sightings and it was observed in the northeastern coastal region the presence of habitats favorable to the occurrence of the species. However, the siltation of rivers and bars, the rectification of river beds for agricultural purposes, deforestation of mangroves, pollution of water resources are some of the factors noted that compromise threatens habitats of manatees and sea irreversibly therefore the species. The harpoon was the main form of capture recorded in the history of hunting, but has not been widely used. The mortality of the animals is linked to events surrounding the stranding of puppies, accidental capture in fishing nets and stalls, hauls made by motorized boats and the use of explosives in fishing activities. From the results obtained, it is recommended the continuation of awareness campaigns along the northeast coast, the monitoring in the main areas of occurrence, the creation of protected areas, environmental education and the inclusion of sites with the highest occurrence of manatees and marine priority areas in the National Plan of Coastal Management.

Prey selectivity of the octocoral Carijoa riisei at Pernambuco, Brazil

This study was designed to evaluate prey selection (type and size) by the octocoral Carijoa riisei at Porto de Galinhas beach, Northeast Brazil, relating prey availability in plankton with the content inside polyps. Diatoms and cyanophytes were the predominant items found in both polyp gastric cavity and plankton. A correlation between prey abundance in the plankton and in the gastric cavity of C. riisei polyps was observed. Mastogloia sp. showed the highest positive electivity index (0.99). Benthonic items were found, with 0.51% of total consumed preys. The size amplitude of prey items in the plankton was similar to those found inside the polyps, although the mean prey size in the polyps (112.7 µm) was significantly lower than the value found in the plankton (240.5 µm). Thus, the study indicates some size selectivity in this species or at least size limitation. From the results, we concluded that the octocoral C. riisei is an opportunistic polyphagous species in the Brazilian northeast coast, showing suspensivorous passive filtering feeding habit with a preference for small prey items and evidencing its important ecological role in the reefal ecosystem as responsible for bidirectional energy transference between pelagic zones and the benthos.

Prey selectivity of the octocoral Carijoa riisei at Pernambuco, Brazil

This study was designed to evaluate prey selection (type and size) by the octocoral Carijoa riisei at Porto de Galinhas beach, Northeast Brazil, relating prey availability in plankton with the content inside polyps. Diatoms and cyanophytes were the predominant items found in both polyp gastric cavity and plankton. A correlation between prey abundance in the plankton and in the gastric cavity of C. riisei polyps was observed. Mastogloia sp. showed the highest positive electivity index (0.99). Benthonic items were found, with 0.51% of total consumed preys. The size amplitude of prey items in the plankton was similar to those found inside the polyps, although the mean prey size in the polyps (112.7 µm) was significantly lower than the value found in the plankton (240.5 µm). Thus, the study indicates some size selectivity in this species or at least size limitation. From the results, we concluded that the octocoral C. riisei is an opportunistic polyphagous species in the Brazilian northeast coast, showing suspensivorous passive filtering feeding habit with a preference for small prey items and evidencing its important ecological role in the reefal ecosystem as responsible for bidirectional energy transference between pelagic zones and the benthos.