Aline do Vale Barreto

Population ecology of the blue crab Callinectes danae (Crustacea: Portunidae) in a Brazilian tropical estuary

This paper aims at describing the population ecology of the swimming crab Callinectes danae Smith, 1869 in one of the most productive estuaries of Brazil, the Santa Cruz Channel. These crabs were monthly collected from January to December/2009 at four stations along the channel, two in the upper and two in the lower estuary. A total of 2373 specimens of C. danae were collected during the study. Males had a larger average carapace width than non-ovigerous females (60.0 ± 15.6 mm and 52.9 ± 12.4 mm, respectively), an adaptation that gives greater protection for females during the copulation. Overall sex ratio did not differ significantly from 1:1. However, evaluating sex-ratio by sampling area, males and juveniles of both sexes occurred preferentially in the upper estuary (p < 0.05), while adult females, including ovigerous, inhabited the lower estuary, an area of major marine influence (p < 0.05). While juveniles look for estuarine waters due to the benefit from the shelter and abundance of food, ovigerous females migrate to areas of greater depth and higher salinity in order to provide a more favorable environment for embryonic and larval development and to enhance larval dispersal. Recruitment of juveniles was continuous along the year, but intensified from March to June and, with less intensity, from October to December.

Reproductive period of the swimming crab Callinectes danae at the Santa Cruz Channel, a highly productive tropical estuary in Brazil

The aim of this study was to analyze reproductive aspects of Callinectes danae in one of the most productive estuarine systems in the Northeast Brazil, Santa Cruz Channel. A total of 1.573 individuals, being 756 females (23 ovigerous) and 817 males were examined from January to December 2009. Mature males and females, as well as couples of C. danae, occurred in all months of the year. Ovigerous females occurred in nearly all months. The reproductive activity, based on the macroscopic observation of the gonads, occurs continuously, with distinguishable peaks in February, March and September. Ovigerous females were only recorded nearest to the sea, while couples were only in the inner estuary. Thus, a migration pattern is proposed, with couples mating inside the estuary, followed by a migration of females to the area of greater marine influence for egg laying and, probably, larval release. After this, probably the females of do not return to the estuary, characterizing habitat partitioning. The present study is the first contribution on the reproductive period of C. danae in an estuarine ecosystem of the Brazilian northeast coast, and elucidates some aspects of its reproductive behavior.

Estádios de desenvolvimento dos órgãos reprodutivos dos machos de Panulirus echinatus Smith (Decapoda: Palinuridae)

Esta pesquisa caracteriza os estadios de desenvolvimento dos testiculos e canais deferentes da lagosta Panulirus echinatus Smith, 1869 a partir da relacao entre seus aspectos macroscopicos, microscopicos e a relacao gonadossomatica (RGS). Atraves de amostragem mensal (novembro de 1999 a outubro de 2000) foram capturados 1716 machos, empregando-se redes de espera de fundo. Retirou-se a regiao dorsal da carapaca para avaliacao dos orgaos reprodutivos. Os testiculos e canais deferentes foram dissecados, pesados, fixados em solucao de Bouin e submetidos aos procedimentos histologicos. A analise microscopica dos orgaos reprodutivos foi avaliada pela presenca ou ausencia de espermatozoides nos testiculos e canais deferentes. Esta, quando associada a macroscopia (mudanca de cor, tamanho, diâmetro e desenvolvimento de espermatoforo) e a relacao gonadossomatica (RGS), possibilitou a caracterizacao de tres estadios de desenvolvimento: imaturo, intermediario e maturo. Ficou evidenciada que a maturidade dos testiculos precedeu a maturidade dos canais deferentes. Para avaliar se a RGS e um bom indicador quantitativo dos estadios de maturidade, um teste t (a = 0,05) foi usado e constatou diferenca significativa nas medias da RGS. A RGS pode ser utilizada como indicadora dos estadios de maturidade para P. echinatus.

Produção de pós-larvas de Macrobrachium amazonicum (Heller, 1862) (Decapoda, Palaemonidae), sob condições controladas de laboratório

Studies on production of post-larvae of the prawn Macrobrachium amazonicum under controlled laboratory conditions were developed at the Departamento de Oceanografia da Universidade Federal de Pernambuco, from September 1980 to February 1982. Experiments were undertaken in aquaria and tanks where the salinity and density of the populations had been changed. The best production was obtained with salinity 14/00 with a density of 38 larvae per litre. The food provided for larvae was crushed fish and nauplii of Artemia salina. Out of 13 experiments a total of 20,000 post-larvae of Macrobrachium amazonicum were obtained.

Biometric relationships of the spotted lobster, Panulirus echinatus , from Tamandaré coastal reefs, Pernambuco State, Brazil

Biometric relationships were recorded for 2431 male and female Panulirus echinatus sampled at Tamandare coastal reefs, Pernambuco, Brazil. The following body measurements were taken: carapace length and width, abdomen length and width, total length, third and fifth pereiopod length, cephalothorax-abdomen and total weight. Twelve relationships were studied to compare the biometric characteristics of males and females. Eleven of them showed difference between the sexes. Comparing sexes with the same carapace length, males have a heavier cephalothorax and longer third and fifth pereiopods than females, whereas females are longer, wider, and have a heavier abdomen than males. For genders with the same total length, males are heavier and have a longer carapace than females, while females have a larger abdomen. For genders with the same abdomen length, males have a heavier abdomen than females. The relationships TWg/TL and A Wg/AL showed positive allometric growth for the males. All other relationships involving weight, presented negative allometric growth for both sexes.

Desenvolvimento dos ovários da lagosta Panulirus echinatus (Crustacea: Palinuridae) baseados nas análises macroscópica, microscópica e relação gonadossomática (RGS)

The developmental stages of the ovaries of the lobster Panulirus echinatus Smith, 1869 were characterized using macroscopic and microscopic features and the gonadosomatic relation (GSR). Based on monthly samples (November, 1999 to October, 2000), a total of 711 females were captured using gillnets. The dorsal region of the carapace was removed to evaluate the ovaries, which were dissected, weighted, preserved in Bouins solution, and submitted to histological procedures. The microscopic analysis of the ovaries was assessed by the presence of germinative cells in different developmental phases. When this analysis was combined with macroscopical observations (changes in color and volume of the gonads in the cephalothorax) and GSR, five developmental stages could be identified: immature (I), intermediate (II); pre-maturation (III); mature (IV) and post-spawning stage (V). Statistical analyses confirmed that GSR can be used as an indicator of developmental stage.