Population attributes of Littoraria angulifera (Gastropoda: Littorinidae) in mangroves in Bahia State, northeastern Brazil

Abstract Littoraria angulifera (Lamarck, 1822) is an estuarine gastropod of tropical occurrence, which lives mainly on trunks of mangrove tree species. This study aimed to evaluate the population attributes of this species, such as abundance, space-time distribution, sex ratio and recruitment in mangroves in Bahia State, northeastern Brazil. The specimens were collected monthly throughout 2018, on trunks of the red mangrove Rhizophora mangle L. at two heights and on two horizontal levels. Specimens that were on the marine grass Spartina alterniflora Loisel were also collected. After counting, biometrics and sexing, the specimens were returned alive to the environment. The average size and weight of L. angulifera was higher (p<0.05) in places with taller and less sparse trees and the vertical distribution on the trunks showed a preference for strata close to the soil. Both results are related to shading and protection against desiccation. Females were more abundant than males, at an approximate sex ratio F: M of 1.4: 1. Recruits were observed throughout the period, showing continuous reproduction of the species with a recruitment peak in spring (September to November). The study revealed the importance of keep the mangroves intact to allow the maintenance of the natural stocks of the species.

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Diel dynamic of phytoplankton functional groups in a tropical water supply, Extremoz Lake, northeastern Brazil

Acta Limnologica Brasiliensia ◽

10.1590/s2179-975x2014000400004 ◽

2014 ◽

Vol 26 (4) ◽

pp. 356-366 ◽

Cited By ~ 1

Author(s):

Thársia da Silva Pinto ◽

Vanessa Becker

Keyword(s):

Vertical Distribution ◽

Functional Groups ◽

Northeastern Brazil ◽

Severe Drought ◽

Dry Period ◽

Drought Period ◽

Tropical Water ◽

Phytoplankton Functional Groups ◽

The Vertical Distribution ◽

Dry And Rainy Seasons

AIM: This study analyzed - the diel and vertical dynamics of phytoplankton functional groups in a natural tropical lake (Extremoz Lake, northeast Brazil), to investigate and understand the driver factors of the community during a severe drought period. METHODS: Sampling of the abiotic variables and phytoplankton was performed at intervals of 6 hours over 24 hours in vertical profiles, in dry and rainy seasons (according to the historical average). The phytoplankton species were grouped according to the functional groups' approach sensu Reynolds et al. (2002). RESULTS: October/12 was considered as a dry period (18.4 mm), while March/13, due to the historical average, as a rainy season, due to the low rainfall during the study period (15.7 mm), it was called severe drought. The lake showed thermal and chemical destratification in both periods. Phytoplankton biomass was higher in the dry season and their vertical distribution was stratified in both periods. In both samplings there were less algal biomass during the night. Phytoplankton functional groups of mixed and shallow systems (S1, L0 and K) were descriptors throughout the study period with higher biomass always registered in the group S1, represented by Planktolyngbya limnetica (Cyanobacteria). CONCLUSION: The lack of seasonality observed in this study, due to prolonged drought, may have influenced the pattern of homogeneous behavior in both samplings. This pattern strongly influenced the vertical distribution of phytoplankton in the two periods, with a constancy of dominance of functional descriptors groups.

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Nesting Substrate Characteristics of Partamona seridoensis Pedro & Camargo (Hymenoptera: Apidae) in Areas of Dry Forest in Brazil

Sociobiology ◽

10.13102/sociobiology.v64i1.1143 ◽

2017 ◽

Vol 64 (1) ◽

pp. 26 ◽

Cited By ~ 2

Author(s):

Carlo Rivero Moura Fernandes ◽

Alerson Brito Almeida ◽

Marco Antonio Del Lama ◽

Celso F Martins

Keyword(s):

Vertical Distribution ◽

Dry Forest ◽

Northeastern Brazil ◽

Nest Entrance ◽

Parental Relationship ◽

Nesting Substrate ◽

First Time ◽

Bee Colonies ◽

The Vertical Distribution

For the first time the association between Partamona seridoensis and Constrictotermes cyphergaster is described. Partamona seridoensis occurs in xeric areas of Northeastern Brazil, and it is a termitophile species as its nests are built in active and inactive arboreal termite nests of the species C. cyphergaster. This study aimed to verify the characteristics of the nesting substrate used by P. seridoensis in two areas of dry forest (caatinga) in Cariri region, Paraíba state. It has been found that the vertical distribution of termites that contained colonies of P. seridoensis varied from 10 cm to 3.60 m, while the height of the nest entrance varied from 20 cm to 3.70 m. Commiphora leptophloeos, popularly known as imburana, was the support tree of 22 (43.1%) from 51 observed termite nests that harbored bee colonies. Most (44; 86.2%) of the host termites colonies were active. Most of the colonies showed the nest entrances not directed to the east/southeast. All colonies located were housed in large termite nests, whose volumes exceed 30 liters. In the two areas surveyed, frequently the entrances of the nests were directed to other nearby colonies, suggesting a parental relationship that should be further investigated.

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Seasonal variation of the crustacean fauna in the belowground and aboveground strata in a Halodule wrightii meadow of northeastern Brazil

Iheringia Série Zoologia ◽

10.1590/1678-4766e2017048 ◽

2017 ◽

Vol 107 (0) ◽

Author(s):

Kcrishna V. S. Barros ◽

Jesser F. Souza-Filho ◽

Ricardo J. C. Paiva ◽

Catarina L. Araújo-Silva ◽

Alexandre O. Almeida ◽

...

Keyword(s):

Spatial Distribution ◽

Seasonal Variation ◽

Vertical Distribution ◽

The Other ◽

Northeastern Brazil ◽

Halodule Wrightii ◽

The Vertical Distribution

ABSTRACT The different microhabitats provided by seagrasses and the habit of the species determinate the vertical distribution of crustaceans. This study verified the influence of the seasonality on the spatial distribution of the crustacean community associated with a Halodule wrightii meadow. From April 2006 to July 2007, we performed fifteen samplings in Goiabeiras Beach, Ceará State, each with five sectioned replicates in belowground and aboveground. Cumaceans and the amphipod Hyale media (Dana, 1853) had a higher frequency, density, and dominance than the other taxa, in both strata. The community exhibited gradual changes along the study, in both the belowground and aboveground strata, but the seagrass structure was not sufficient to explain the vertical distribution of the crustacean fauna along the time.

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Diel Pelagic Foraging by a Pandalid Shrimp (Pandalus montagui) off Resolution Island (Eastern Hudson Strait)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f92-066 ◽

1992 ◽

Vol 49 (3) ◽

pp. 565-576 ◽

Cited By ~ 5

Author(s):

C. Hudon ◽

D. G. Parsons ◽

R. Crawford

Keyword(s):

Sex Ratio ◽

Vertical Distribution ◽

Feeding Activity ◽

Bottom Trawl ◽

Staple Food ◽

Benthic Organisms ◽

Size Frequency Distribution ◽

Ratio Size ◽

Plankton Sampler ◽

The Vertical Distribution

The vertical distribution and diet of shrimp (Pandalus montagui) were investigated using a multistage plankton sampler (BIONESS) and were compared with those of shrimp captured on the bottom using a trawl. Massive nocturnal vertical migrations of shrimp were observed in association with intense pelagic feeding activity. The sex ratio, size frequency distribution, and diet of shrimp caught in the water column differed markedly from shrimp caught during their stay on the bottom. Pelagic migrants were mostly males (75%), extending their planktonic foray into morning hours, whereas ovigerous (12%) and nonovigerous (13%) females returned to the bottom at dawn. In the trawl, the representation of males (43%) and ovigerous females (45%) differed, but also fluctuated on a diel cycle. Stomachs of shrimp captured in the BIONESS were fuller and the contents were in better condition than found in shrimps captured in the bottom trawl. Pelagic shrimp fed opportunistically on a variety of zooplankters, using copepods as a staple food. Stomachs of shrimp from the bottom trawl contained chitinous debris, sand grains, and small amounts of benthic organisms. The occurrence of daily vertical feeding migrations results in the unavailability of a variable proportion of the total shrimp biomass to bottom trawls.

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