The biggest or the most abundant? Predation of the Black Drum Pogonias cromis (Perciformes, Sciaenidae) on benthic organisms in southern Brazil

Predators that consume larger prey acquire a greater net return of energy per individual, even though they are less abundant. The objective of this work is to analyze the feeding biology of Pogonias cromis in southern Brazil, in order to test for the occurrence of ontogenetic changes in diet as fish reach larger sizes, by consuming larger prey as they grow. Between August 2014 and May 2016, 347 specimens were collected from catches of the fishing fleet that operate in the Patos lagoon estuary and in the adjacent marine area of Cassino beach, that use artisanal fishing gillnets. The prey-specific relative importance index, food overlap, niche breadth and prey length preference were calculated for three length classes, class 1 (27.8–48.73 cm), class 2 (48.73–69.66 cm) and class 3 (69.66–90.60 cm). A total of 13 food items (6 species of crustaceans, 5 species of mollusks, fish fragments and non-animal fragments) were identified, where two species of mollusks (Heleobia australis and Erodona mactroides) represented 90.49% of the diet. The overlap index was moderate between classes 1 and 2, high between 2 and 3 and moderate between 1 and 3. There was a low niche breadth at the population level and for each length class. There were no significant differences in the length of prey consumed among classes. The data obtained here indicates that P. cromis can be classified as a predator specialized in mollusks, with low tendency to ontogenetic changes in southern Brazil. Considering information from the population of P. cromis from Argentina, it can be inferred that the species in the waters of southern South America is a benthic predator adapted to local conditions.

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Temporal Variability of Suspended-Solids Concentration in the Estuarine Channel of Patos Lagoon, Southern Brazil

Water ◽

10.3390/w13050646 ◽

2021 ◽

Vol 13 (5) ◽

pp. 646

Author(s):

Rafael André Ávila ◽

Priscila Mulattieri Suarez Orozco ◽

Mauro Michelena Andrade ◽

Osmar Olinto Möller

Keyword(s):

Temporal Variability ◽

Suspended Solids ◽

Southern Brazil ◽

Patos Lagoon ◽

Reliable Technique ◽

Acoustic Data ◽

Solids Concentration ◽

Estuarine Hydrodynamics ◽

Inflow Conditions

The assessment of suspended-solids dynamics is crucial for the effective monitoring of estuarine environments. As the recurring in-situ sampling is usually problematic, the calibration of the backscattering from acoustic Doppler profilers has shown to be a reliable technique to estimate the suspended-solids concentration (SSC) in estuaries and rivers. In this study, we obtained a linear model that provides SSC estimates for the estuarine channel of Patos Lagoon by calibrating turbidity and acoustic data with in-situ concentration samples. The model output was analyzed in terms of its relationship with estuarine hydrodynamics and temporal variability. In this estuary, the supply of suspended solids is known to be due the runoff from its main tributaries, but also through the exchanges between the estuary and the coastal ocean. Both sources provide sediments and organic solids which affect water quality, geomorphology, and harbor operations. Results show that SSC is strongly linked to estuarine hydrodynamics, where concentrations increase with streamflow. During outflow periods, higher concentrations are associated with river runoff, whereas with inflow conditions they are induced by southern and southwesterly winds. However, relationship between SSC and streamflow is asymmetrical, meaning that the largest concentrations are majorly linked to outflow currents and downstream transport.

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Diet and feeding strategy of the dusky grouper Mycteroperca marginata (Actinopterygii: Epinephelidae) in a man-made rocky habitat in southern Brazil

Neotropical Ichthyology ◽

10.1590/s1679-62252011005000006 ◽

2011 ◽

Vol 9 (1) ◽

pp. 161-168 ◽

Cited By ~ 11

Author(s):

Mario V. Condini ◽

Elisa Seyboth ◽

João P. Vieira ◽

Alexandre M. Garcia

Keyword(s):

Feeding Strategy ◽

Marine Species ◽

Southern Brazil ◽

Patos Lagoon ◽

Additional Tool ◽

Rocky Habitat ◽

Dusky Grouper ◽

Dietary Shifts ◽

Rocky Habitats ◽

Rocky Bottoms

The dusky grouper (Mycteroperca marginata) is a marine species usually associated with rocky bottoms and reefs. The present work investigated the diet and feeding strategy of a dusky grouper population inhabiting a 4.5 km long pair of rocky jetties located in the mouth of Patos Lagoon estuary. No prior research has been conducted in such man-made habitat and the current study provides a basis for comparative studies on the diet of the dusky grouper populations inhabiting natural vs. man-made rocky habitats. Similarly with previous studies on natural substrates, crabs and fishes were the main food categories consumed (%IRI = 85.1 and %IRI = 12.6, respectively), whereas shrimps and mollusks had lower importance in the diet (%IRI = 1.9 and 0.4, respectively). As previously reported for dusky grouper populations inhabiting reefs and rocky bottoms, the present work revealed conspicuous size related dietary shifts. Blue crabs and fishes become increasingly important food items in the diet of larger individuals (> 500 mm, TL). Finally, it was found that the studied dusky population has a generalist feeding strategy with a high between-individual variation in prey consumption. Such strategy remained similar across the size increment of the species. Our findings suggest that man-made rocky substrates provide suitable feeding grounds for the dusky grouper in southern Brazil and could be used as an additional tool in the conservation efforts of this endangered species.

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AGROCLIMATIC ZONING OF EUROPEAN AND ASIAN PEAR CULTIVARS WITH POTENTIAL FOR COMMERCIAL PLANTING IN SOUTHERN BRAZIL

Revista Brasileira de Fruticultura ◽

10.1590/0100-29452017312 ◽

2017 ◽

Vol 39 (2) ◽

Author(s):

MARCOS SILVEIRA WREGE ◽

IVAN DAGOBERTO FAORO ◽

FLÁVIO GILBERTO HERTER ◽

CRISTINA PANDOLFO ◽

IVAN RODRIGUES DE ALMEIDA ◽

...

Keyword(s):

Fruit Quality ◽

Climate Risk ◽

Southern Brazil ◽

Climatic Zones ◽

Local Conditions ◽

Asian Pear ◽

Commercial Interest ◽

The World ◽

Chilling Hours ◽

Production Problems

ABSTRACT Pear is among the fruits of major commercial interest in the world and one of the most imported in Brazil. Brazilian production is very small and the fruit quality is low, due to production problems. The success of culture in the country, among other factors, may be linked to the choice of cultivars, pollinating and rootstocks better adapted to local conditions, and thus depend on the particulars of an agricultural zoning. The aim of this study was to identify, in southern Brazil, homogeneous climatic zones with potential for growing of European and Asian pears, through climate risk studies. The regions were defined by the seasonal availability of chilling hours (<7.2 °C) accumulated during the period from May to September and the monthly risk of drought. The analysis allowed the recognition of four homogeneous areas for the production of pears in southern Brazil.

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Activity budgets and distribution of bottlenose dolphins (Tursiops truncatus) in the Patos Lagoon estuary, southern Brazil

Latin American Journal of Aquatic Mammals ◽

10.5597/lajam00121 ◽

2007 ◽

Vol 6 (2) ◽

Cited By ~ 10

Author(s):

P. H. Mattos ◽

L. Dalla Rosa ◽

P. F. Fruet

Keyword(s):

Tursiops Truncatus ◽

Bottlenose Dolphins ◽

Southern Brazil ◽

Activity Budgets ◽

Patos Lagoon ◽

Patos Lagoon Estuary

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Archaeological Earthen Mound Complex in Patos Lagoon, Southern Brazil: Chronological Model and Freshwater Influence

Radiocarbon ◽

10.1017/rdc.2017.5 ◽

2017 ◽

Vol 59 (1) ◽

pp. 195-214 ◽

Cited By ~ 11

Author(s):

Rafael G Milheira ◽

Kita D Macario ◽

Ingrid S Chanca ◽

Eduardo Q Alves

Keyword(s):

Archaeological Sites ◽

Human Intervention ◽

Southern Brazil ◽

Patos Lagoon ◽

Lagoon System ◽

Indigenous Groups ◽

Freshwater Influence ◽

Intense Activity

AbstractIn the present work, we assess the chronology of archaeological sites known as earthen mounds, commonly found at the Pampas biome, among the lowlands of Brazil, Uruguay, and Argentina. We focused on the Pontal da Barra settlement, which is a testimony of the long-term occupation of indigenous groups in the swamp and wet environment of Patos Lagoon, southern Brazil. A Bayesian chronological model based on the radiocarbon (14C) dating of 17 samples of fish otolith, 5 charcoal fragments, and 2 bones (human and dog) allowed determination of the beginning of the occupation as well as the occupational synchronism of the different mounds. The nature of the samples allows us to study the local 14C reservoir effect through the comparison between the group of marine and terrestrial samples, deriving a reservoir offset value of 63±53 14C yr for this particular area, indicating a strong freshwater influence in the lagoon system. We estimate the start of human intervention in the landscapes of southern Patos Lagoon to be around 2200 cal BP, with the most intense activity between 1800 and 1200 cal BP.

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Feeding activity of the cayenne pompano Trachinotus cayennensis (Cuvier 1832) (Perciformes, Carangidae) in estuaries on the western coast of the state of Maranhão, Brazil

Brazilian Journal of Biology ◽

10.1590/1519-6984.182683 ◽

2019 ◽

Vol 79 (2) ◽

pp. 311-320

Author(s):

A. C. L. Castro ◽

J. W. J. Azevedo ◽

H. R. S. Ferreira ◽

L. S. Soares ◽

J. R. Pinheiro-Júnior ◽

...

Keyword(s):

Size Range ◽

Eating Habits ◽

Feeding Activity ◽

The State ◽

Western Coast ◽

Ontogenetic Changes ◽

Importance Index ◽

Size Groups ◽

Subsequent Calculation ◽

Feeding Plasticity

Abstract The present paper addresses the feeding activity of Trachinotus cayennensis, collected in Lençóis Bay (1°18’S – 1°19’S; 44°51’W – 44°53’W) on the western coast of the state of Maranhão, Brazil. Sampling was conducted between June 2012 and June 2013 using driftnets with stretch mesh sizes from 95 to 100 mm. A total of 205 individuals (114 females and 91 males) were analyzed. Statistically significant differences in the sex ratio were found in June, September and December 2012. Food items were analyzed based on frequency of occurrence and volumetric method, with the subsequent calculation of the alimentary importance index. Three size groups were defined to determine possible ontogenetic changes in eating habits based on the size range of the individuals collected: I (˂ 29 cm), II (29.1 to 37.0) and III (≥ 37.1). Eleven food item categories were identified: mollusks, polychaetes, crustaceans, nematodes, insects, algae, bryozoans, ophiuroids, fishes, vegetal matter and sediments. The variety of items in the diet of T. cayennensis indicates considerable feeding plasticity and opportunistic behavior. Seasonal variations influenced the feeding pattern of the species, with greater feeding activity in the dry season. The considerable availability of resources in estuarine habitats of the western coast of Maranhão constitutes another factor that influences the feeding behavior of this species.

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The immunogenetics of multiple sclerosis. The frequency of HLA-alleles class 1 and 2 is lower in Southern Brazil than in the European population

Arquivos de Neuro-Psiquiatria ◽

10.1590/0004-282x20160100 ◽

2016 ◽

Vol 74 (8) ◽

pp. 607-616 ◽

Cited By ~ 4

Author(s):

Lineu Cesar Werneck ◽

Paulo José Lorenzoni ◽

Raquel Cristina Arndt ◽

Cláudia Suemi Kamoi Kay ◽

Rosana Herminia Scola

Keyword(s):

Multiple Sclerosis ◽

High Resolution ◽

Direct Sequencing ◽

Positive Association ◽

Statistical Correlation ◽

European Population ◽

Southern Brazil ◽

Bonferroni Correction ◽

Hla Alleles ◽

Class 1

ABSTRACT Objective To study the HLA of class 1and 2 in a multiple sclerosis (MS) population to verify the susceptibility for the disease in the Southern Brazil. Methods We analyzed patients with MS and controls, by direct sequencing of the genes related to HLA DRB1, DQB1, DPB1, A, B and C alleles with high resolution techniques. Results We found a lower frequency of all HLA alleles class 1 and 2 in MS and controls comparing to the European population. Several alleles had statistical correlation, but after Bonferroni correction, the only allele with significance was the HLA-DQB1*02:03, which has a positive association with MS. Conclusions Our data have different frequency of HLA-alleles than the previous published papers in the Southeast Brazil and European population, possible due to several ethnic backgrounds.

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