Este estudo teve como objetivo avaliar a distribuição espaço-temporal, biologia populacional e dieta de Menticirrhus americanus da baía de Caraguatatuba. Foram realizadas coletas mensais entre agosto de 2003 a outubro de 2004, utilizando redes de arrasto em duas áreas previamente selecionadas. A área norte é mais expostas à atividade de onda e é influenciada por um rio, constituindo um pequeno estuário. Por outro lado, a área sul é relativamente protegida da energia das ondas e sofre pouca influência dos rios. Os indivíduos coletados foram medidos e identificados macroscopicamente quanto ao sexo e o estádio gonadal. A abundância da espécie foi comparada entre as áreas e entre os meses de coleta. Para a dieta os itens alimentares encontrados foram identificados e quantificados. M. americanus apresentou proporções equivalentes nas duas áreas de estudo, sendo mais abundante em abril de 2004, seguido por dezembro de 2003 e janeiro de 2004. A população região é composta por indivíduos imaturos, e os poucos indivíduos maduros ou em maturação capturados não apresentaram padrão de distribuição ao longo do ano. A espécie mostrou uma dieta variada, alimentando-se de vermes (nemertideos, sipúnculos e equiúros), moluscos (bivalves e cefalópodes), poliquetas, crustáceos e peixes. A presença de nematóides intactos na porção do intestino sugere uma relação parasitária. Os resultados demonstraram que os indivíduos de Menticirrhus americanus estiveram uniformemente distribuídos nas áreas norte e sul e também ao longo do ano. A espécie pode ser considerada predadora e carnívora, mostrando preferência na alimentação por espécies bentônicas de fundos não consolidados, tais como geicerídeos e outros poliquetas, crustáceos e sifões de bivalves.

This study evaluated the spatio-temporal distribution, population biology and diet of Menticirrhus americanus in Caraguatatuba Bay. Samples were taken monthly between August 2003 and October 2004, by trawling in two previously selected areas. The northern area is more exposed to wave activity and is influenced by a river, functioning as a small estuary. In contrast, the southern area is relatively sheltered from wave energy and influenced to a lesser degree by smaller rivers. The fishes' length was measured, and the sex and gonadal stage macroscopically identified. The abundance of this species was compared between areas and among months. The diet was identified and quantified. M. americanus occurred in equal proportions in the two study areas, being most abundant in April 2004, followed by December 2003 and January 2004. The population was dominated by small immature individuals. The few individuals in maturation or mature that were captured showed no seasonal pattern of distribution. This species had a varied diet, feeding on worms (nemerteans, sipunculans and echiurans), mollusks (bivalves and cephalopods), polychaetes, crustaceans and fish. The presence of intact nematodes in the intestine suggests that these are parasites. The results demonstrated that M. americanus has a homogeneous spatial and temporal distribution in Caraguatatuba Bay, being uniformly distributed between the south and north areas as well as across the months. This species can be considered a carnivorous predator, showing a preference for consuming benthic sandy-beach species such as glycerids and other polychaetes, crustaceans, and bivalve siphons.

The composition and seasonal variation of brachyuran and anomuran species associated with mussel farms were evaluated at Praia da Cocanha, São Paulo between May 2007 and February 2008. Nine mussel ropes were sampled at random in each quarter, and 1,208 organisms were identified, comprising five families and 28 species. The most numerous species was the porcellanid Pachycheles laevidactylus (18.5%), followed by the xanthids Acantholobulus schmitti (16.6%), Hexapanopeus paulensis (11.3%), Panopeus americanus (10.2%), and Menippe nodifrons (8.4%). The exotic crab Charybdis hellerii was recorded throughout the study period. The ecological descriptors, except Pielou evenness index, varied significantly over the time. The highest abundance and diversity of the species were recorded during November and February. This pattern was reversed for Berger-Parker dominance, with the lowest values recorded in February. The development of epifauna was correlated with the different stages of the mussel farms, since the mean size of mussels and consequently the abundance of epibiotic organisms and the structural complexity on the mussel ropes increased from May (seeding) until February (harvest). Despite this, the temporal population variations in recruitment patterns of the different epibionts should not be overlooked. The results indicated that the mussel farms provided favorable conditions for the development of these crustacean groups, which could be used in environmental monitoring programs and / or be exploited for the aquarium trade.