Navegando por Assunto "Rio Caeté - PA"

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Acesso aberto (Open Access)
Biologia e estrutura populacional das espécies da família sciaenidae (Pisces : Perciformes), no estuário do rio Caetê município de Bragança, Pará-Brasil
(Universidade Federal do Pará, 1999-03) CAMARGO-ZORRO, Mauricio; ISAAC, Victoria Judith; http://lattes.cnpq.br/3696530797888724
This study aimed to assess the average biomass and spatial and temporal distribution of the family Sciaenidae fishes in the estuary of the Caeté River, northern of Brazil, with special reference to the species Stellifer rastrifer, Stellifer naso, Macrodon ancylodon and Cynoscion microlepidotus. Age at first sexual maturity (L50), spawning season, the length-weight relationships, food diet, population consumption by biomass (Q/B), population structure and dynamics were estimated. 6 Bimonthly samples were taken in the estuarine area of the Caeté River, from October 1996 to August 1997. The average biomass of the family Sciaenidae was 0,840g/m². The spatial distribution in the system was related to spawning and recruitment. Juveniles of S. rastrifer, S. naso e M. ancylodon occurred inside some areas in the estuary, although larger individuals were abundant outside where salinity is higher. The L50 values were 10cm, 10,7cm e 21,5cm respectively. Two spawning periods in a year were found, which determine the recruitment of two cohorts, with different growth parameters. The length-weight relations were allometric and no differences were found by sex. An ontogenetic change was found in the diet composition of these species; young prey zooplancton and adults feed predominantly on larval stages of decapodes and poliquetes, and juveniles of fishes. Diet overlaps changed during the ontogenic development of each species. The relation Q/B indicated that S. rastrifer and S. naso consume more food in relation to the body size, in opposite to the larger species like M. ancylodon and C. microlepidotus. The fishes of the Caeté River presented higher growth and low longevity when compared to the same species inhabit the higher latitudes.
Acesso aberto (Open Access)
Comparative morphology of the first zoea of twelve brachyuran species (Crustacea: Decapoda) from the Amazon region
(2013-06) SOUZA, Adelson Silva de; COSTA, Rauquírio André Albuquerque Marinho da; ABRUNHOSA, Fernando Araujo
The laboratory-hatched first zoeal stage of twelve brachyuran species collected in the estuarine area of the Caeté River in the Amazonian region are described and illustrated in the present study: P. americanus Saussure, 1857, Eurytium limosum (Say, 1818), Sesarma curacaoense De Man, 1892, S. rectum Randall, 1840, Armases rubripes (Rathbun, 1897), Aratus pisonii (H. Milne Edwards, 1837), Ocypode quadrata (Fabricius, 1787), Uca rapax (Smith, 1870), U. maracoani (Latreille, 1802), U. thayeri Rathbun, 1900, Ucides cordatus (Linnaeus, 1763) and Pachygrapsus gracilis (Saussure, 1858). Through intraspecific comparisons of the respective larval stage, an identification key was generated and provided. Most of the studied species presented morphological differences (e.g. type and presence or absence of setae) when compared to the same species previously described in the literature.
Acesso aberto (Open Access)
A comunidade zooplanctônica em um canal de maré no estuário do rio Caeté, Bragança (Pará, Brasil)
(Universidade Federal do Pará, 1999-04-30) PERES, Ariadne da Costa; ISAAC, Victoria Judith; http://lattes.cnpq.br/3696530797888724
There are few studies mede about zooplankton in estuaries of Bragança region, Pará State. This work was done in a tidal creek, named Furo do Chato, next to Ajuruteua, Bragança's district which is part of Pará State seashore and aimed to study lhe zooplankton qualitative and quantitative composition, as well as lhe sazonal variations and the environmental effect variables of the zooplankton composition. From August/96 to January/97 every three weeks for a period of 24 hours, zooplankton samples were taken every two hours. Furo do Chato is a tida l creek with strong coaste! influence. Hence the great majority of lhe zooplankton categories found are from coaste! water. Besides holoplankton and meroplankton components, lhe zooplankton samples from Furo do Chato has a strong bentonic component. Ten phyla were identified: Protozoa, Mollusca, Chordata, Annelida, Cnidaria, Arthropoda, Urochodata, Chaetognatha, Nematoda e Bryozoa. The Copepoda class had higher representative, even for density, biomass as well as occurrence frequency in the community. The most abundant and frequent Categories (>40%) were Pseudodiaptomus marshi, Acartia lilljeborgi, Acartia tansa, Harpacticoida, Sagitta sp., Oikopleura dioica, Cnidaria, Isopoda, crabs zoeas, shrimps post-larvae and fish larvae. The average densities and biomass were low (1,07 indiv./m³ e 16,43 mg/m³). The zooplankton community is more abundant in the transition months than in the dry period. The highest abundances took place at night and during the spring lides. Tide, salinity and different moon phases did not infiuence in the zooplankton as a whole, but only in some categories isolated.
Acesso aberto (Open Access)
Descrição larval de caranguejos brachyura (Crustacea: Decapoda) da região Amazônica, obtido em laboratório
(Universidade Federal do Pará, 2011-07-11) SOUZA, Adelson Silva de; COSTA, Rauquírio André Albuquerque Marinho da; http://lattes.cnpq.br/4504677939464624; ABRUNHOSA, Fernando Araujo; http://lattes.cnpq.br/9557937645632227
Larvae of the mud crab P. lacustris were reared in laboratory from ovigerous females collected in the estuarine area of the Caeté River in the Amazonian region. The complete development of this species consisted of 4 zoeal and 1 megalopal stages, where each stage was described and illustrated in detail. The results were compared with those of other previous studies on larval development of the species belonging to the genus Panopeus and then briefly discussed. Besides the description of the complete development larval of P. lacustris, has been described and illustrated the first stage zoea of thirteen species of brachyuran crabs collected in the same estuary: P. lacustris Desbonne, 1867, P. americanus Saussure, 1857, Eurytium limosum (Say, 1818), Sesarma curacaoense De Man, 1892, Sesarma rectum Randall, 1840, Armases rubripes (Rathbun, 1897), Aratus pisonii (H. Milne Edwards, 1837), Ocypode quadrata (Fabricius, 1787), Uca rapax (Smith, 1870), Uca maracoani (Latreille, 1802), Uca thayeri Rathbun, 1900, Ucides cordatus (Linnaeus, 1763) e Pachygrapsus gracilis (Saussure, 1858). Only the zoea I of P. lacustris was not described again. The morphological characteristics of these species are compared with the original descriptions. To make easy the study of plankton-collected material, it was developed a key to identification of the species described in this study.
Acesso aberto (Open Access)
Dinâmica da paisagem e o processo de fragmentação florestal na bacia do Caeté
(Universidade Federal do Pará, 2018-02-23) SANTOS, Milena de Nazaré Silva; LIMA, Aline Maria Meiguins de; http://lattes.cnpq.br/6572852379381594
The Caeté River Basin is located in a very strategic region of the north-eastern region of Pará and has high levels of anthropization. In this scenario, the landscape has been transformed concomitantly to the processes of consolidation and expansion of the different types of land use and land cover. Thus, this work presents the landscape dynamics and forest fragmentation process for the Caeté Basin in the years 2004, 2010 and 2014 and its implications in the modulation of the contemporary space scenario. For this, the research is based on the following discussions: I - Comparison of land use and land use transition dynamics in the basin, using multitemporal analysis, based on TerraClass cartographic bases and Landsat / TM 5 satellite images, orbits 222 and 223, point 061, bands 3, 4 and 5, for the year 2004. II- Characterization and quantification of the fragments and configuration of the local landscape structure, based on landscape metrics and the use of the software Fragstats version 4.2. III- Identification of anthropic pressures and fragmentation reflexes on the Caeté-Taperaçu Conservation Unit. In 2004 the pasture, forest and occupation mosaic classes elucidated a percentage of 80.39% of the total area of the basin. In 2014 the areas contained in these same classes totaled 87.26%. The indicative presented demarcates the intense consolidated spatial dynamics on the basin. The indices calculated in this section confirmed the predominance of pasture in the Caeté basin, using the Class Area (CA) and Percentage of Fragments (PLAND) metrics. On the other hand, the Total Edge (ET) and Edge Density (ED) indices showed that the process of forest fragmentation in the basin has been attenuated, due to the predominant edge indices on the forest class. The Caeté-Taperaçu Conservation Unit presented a significant contribution to the processes of use and occupation in the region acting as an instrument to contain environmental impacts. The relevance of the research is represented by the integration of socio-environmental aspects associated with landscape dynamics, considering how human actions can affect the natural resource balance. It is hoped that data presented contribute as a subsidy for the integrated and participatory management of water resources.
Acesso aberto (Open Access)
Feeding and larval growth of an exotic freshwater prawn Macrobrachium equidens (Decapoda: Palaemonidae), from Northeastern Pará, Amazon Region
(2014-09) GOMES, Jean Neves; ABRUNHOSA, Fernando Araujo; COSTA, Anne Karoline Ribeiro; MACIEL, Cristiana Ramalho
In the present study, we carried out experiments on the diet of the freshwater prawn Macrobrachium equidens. We tested which type of food and which density of food is suitable for larval development. For the experiment on the type of food, eight treatments were carried out: (I) starvation, (AL) microalgae, (RO) rotifers, (AN) Artemia, (RO + AN) rotifers + Artemia, (AL + RO) microalgae + rotifers, (AL + AN) microalgae + Artemia, (AL + RO + AN) microalgae + rotifers + Artemia. For the experiment on the density of food, we used the type of food, which had resulted in a high survival rate in the previous experiment. Three treatments were carried out: 4, 8 and 16 Artemia nauplii /mL. The rate of feeding during larval development was observed. The survival, weight and percentage of juveniles of each feeding experiment were determined. We found that larvae are carnivores; however, they have requirements with respect to the type of food, because larvae completed their cycle from the zoeal to the juvenile stage only when Artemia nauplii were available. We also verified that the larvae feed mainly during the day-time, and are opportunistic with respect to the density of food offered.
Acesso aberto (Open Access)
Foregut morphology of Pseudothelphusidae and Trichodactylidae (Decapoda: Brachyura) from northeastern Pará, Brazil
(2010-04) ALVES, Soraya Tatiana Macêdo; ABRUNHOSA, Fernando Araujo; LIMA, Jô de Farias
The gross morphology of foregut was investigated and described in detail for four freshwater crab species: a pseudothelphusid, Fredius reflexifrons (Ortmann, 1897) and three trichodactylids - Sylviocarcinus pictus (H. Milne-Edwards, 1853), Valdivia serrata White, 1847, and Dilocarcinus septemdentatus (Herbst, 1783). In general, the gastric mills of freshwater crabs showed a similar degree of complexity in relation to other marine species of Anomura and Brachyura previously described in the literature. However, significant morphological differences were observed among the analyzed species, as in ossicle numbers, features and connection types. A total of 38 ossicles were described for S. pictus and V. serrata and 37 ossicles for D. septemdentatus and F. reflexifrons, respectively. The latter species can be distinguished from the others by the presence of a wide cardiac sac resembling two sacs. Most of the ossicles were connected through a rigid connection, and few ossicles were fused. The degree of calcification varied little among the studied species. The differences found among the species suggest that the morphological aspects of the foregut may be useful in the identification of similar species.
Acesso aberto (Open Access)
Influence of natural settlement cues on the metamorphosis of fiddler crab megalopae, Uca vocator (Decapoda: Ocypodidae)
(2010-06) SIMITH, Darlan de Jesus de Brito; ABRUNHOSA, Fernando Araujo; DIELE, Karen
Megalopae of many decapod crab species accelerate their development time to metamorphosis (TTM) when exposed to natural physical and/or chemical cues characteristic of the parental habitat. In the present study, the influence of natural settlement cues on the moulting rates and development TTM in megalopae of the fiddler crab Uca vocator was investigated. The effects of mud from different habitats (including well-preserved and degraded-polluted mangrove habitats) and conspecific adult 'odours' (seawater conditioned with crabs) on the induction of metamorphosis were compared with filtered pure seawater (control). 95 to 100% of the megalopae successfully metamorphosed to first juvenile crab stage in all treatments, including the control. However, the development TTM differed significantly among treatments. Settlement cues significantly shortened development, while moulting was delayed in their absence. The fact that megalopae responded to metamorphosis-stimulating cues originating from both adult and non-adult benthic habitats demonstrates that settlement in this species may occur in a wider range of habitats within the mangrove ecosystem, including impacted areas.
Acesso aberto (Open Access)
Sciaenidae fish of the Caeté River estuary, Northern Brazil: mitochondrial DNA suggests explosive radiation for the Western Atlantic assemblage
(2004) VINSON, Christina Cleo; GOMES, Grazielle Fernanda Evangelista; SCHNEIDER, Horacio; SAMPAIO, Maria Iracilda da Cunha
Sciaenids are fish which are normally abundant in tropical estuaries of the western Atlantic. Studies on the Caeté river estuary in the northern Brazilian state of Pará have revealed that in this area Sciaenidae is the dominant family, comprising almost 50% of all teleosts sampled. In this paper we present the results of the first phylogenetic study on South American estuarine sciaenids, during which we obtained mitochondrial gene 16S sequences from 15 species belonging to eight genera occurring in the Caeté estuary. Intergeneric nucleotide divergences varied from 5 to 15%, Lonchurus and Menticirrhus being the most divergent lineages. Nucleotide divergences were quite variable amongst species of the same genus, ranging from 1.2% (Stellifer microps x Stellifer naso) to 8.4% (Menticirrhus americanus x Menticirrhus littoralis). Cladograms based on maximum parsimony, minimum evolution and maximum likelihood depicted an explosive diversification pattern for the western Atlantic sciaenid assemblage. Our analysis further reveals a very close relationship between Bairdiella and Stellifer, a monophyletic clade which emerged during the more recent diversification events of the Sciaenidae family. The phylogenetic reconstruction suggests the need for a revision of the taxonomy and nomenclature of the Bairdiella/Stellifer group.
Acesso aberto (Open Access)
The complete larval development of Armases benedicti (Rathbun) (Decapoda, Sesarmidae), from the Amazon region, reared in the laboratory
(2006-06) LIMA, Jô de Farias; ABRUNHOSA, Fernando Araujo
The four zoeal and one megalopal stages of the wharf crab Armases benedicti (Rathbun, 1897) larvae reared in the laboratory are described and illustrated in detail. The mean duration for each larval stage was 3, 2, 4, 4 and 13 days, respectively. The duration of the larval period from hatching to the first juvenile was 26 days. Morphologically, A. benedicti is very similar to the reported species of genus. However, a small lateral spine is clearly observed in the carapace of zoeal stages of this species. This feature appears to be unique among the family Sesarmidae. Another distinctive character for this species is the zoeal setation of the maxilla endopod (2+2) in which most of the sesarmids have setation (2+3) except for Sesarma tetragonum (Fabricius, 1798). Other comparisons with previous larval studies of the genus Armases Abele, 1992 are briefly discussed.