Individual growth and mortality of Rhithropanopeus harrisii (Decapoda: Panopeidae) in the estuarine region of Patos Lagoon, Southern Brazil

Kalliapseudes schubartii (Crustacea: Tanaidacea) is a tube dwelling invertebrate living in estuarine soft bottoms with distribution along the south-east and southern Brazilian and Uruguayan coasts. Individual growth, and reproduction were examined by taking samples for a year in the estuarine region of the Lagoa dos Patos (southern Brazil). The von Bertalanffy model described growth of K. schubartii (K=4.54 y−1, L∞=13.22 mm). Reproductive activity was observed in spring and summer. No relationship was observed between total length of females and brood size. Eggs, embryos, and mancas were often observed in a marsupium. Relative growth analysis showed two levels of allometry in the growth of chelipeds of males.

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Effects of dredging operations on soft bottom macrofauna in a harbor in the Patos Lagoon estuarine region of southern Brazil

Brazilian Journal of Biology ◽

10.1590/s1519-69842005000400003 ◽

2005 ◽

Vol 65 (4) ◽

pp. 573-581 ◽

Cited By ~ 18

Author(s):

C. E. Bemvenuti ◽

L. G. Angonesi ◽

M. S. Gandra

Keyword(s):

Cluster Analysis ◽

Rio Grande ◽

Sampling Period ◽

Southern Brazil ◽

Soft Bottom ◽

Patos Lagoon ◽

Bottom Community ◽

Estuarine Species ◽

Estuarine Region

An evaluation was made of the effects of dredging on the soft bottom community in the channel of the Rio Grande harbor in the Patos Lagoon estuarine region of southern Brazil. During four seasonal cruises, samples were collected from nine biological stations, one of which was located outside the dredged area. Three macrobenthic samples were collected on each cruise from each station, using a 0.08 m² van Veen grab. A cluster analysis was applied to group summer and autumn cruise stations before the dredging period, revealing larger numbers of species (35-36 spp.) and higher densities of organisms. The station located outside the dredging area was always included in this group, regardless of the sampling period or conditions of salinity. Another group comprised the winter and spring stations during the dredging period. This group was characterized by stations with the fewest species (20-18 spp.) and the lowest and most variable organism densities. The efficient strategies of resilience of the dominant estuarine species may minimize the effects of dredging on the biota through the rapid recolonization of the soft bottom of the harbor channel.

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Reproductive biology of Neohelice granulata (Decapoda: Varunidae) in two salt marshes of the estuarine region of the Lagoa dos Patos Lagoon, southern Brazil

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s002531540800252x ◽

2008 ◽

Vol 89 (4) ◽

pp. 769-774 ◽

Cited By ~ 3

Author(s):

Roberta A. Barutot ◽

Fernando D'Incao ◽

Duane B. Fonseca

Keyword(s):

Reproductive Biology ◽

Salt Marshes ◽

Atlantic Coast ◽

Organic Matter Content ◽

Matter Content ◽

Southern Brazil ◽

Patos Lagoon ◽

Neohelice Granulata ◽

Males And Females ◽

Estuarine Region

Neohelice granulata is a crab found in salt marshes and mangroves of the south and south-eastern Atlantic coast of South America. Reproductive biology was studied by taking samples for two years at two salt marshes—‘Prainha’ and ‘Ilha’—in the estuarine region of Patos Lagoon (southern Brazil). Ovigerous females were found most of the year in both salt marshes with average CW ranging from 18.5 (Prainha) to 22.8 mm (Ilha). A significant linear relationship was found between log(CW) and log(number of eggs). Average size at the onset of maturation was 14.9 and 14 mm at Prainha, for males and females, respectively, while at Ilha it was 18.2 and 16.8 mm, for males and females, respectively. Results provided evidence of significant differences in reproductive traits between populations of the two salt marshes. Differences are likely related to the higher organic matter content found in the sediment from Ilha.

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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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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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