This paper has identified, for the first time in a member of the Rhodophyta, a vacuolar organelle containing enzymes that are involved in the mevalonate pathway-an important step in red algal isoprenoid biosynthesis. These organelles were named mevalonosomes (Mev) and were found in the cortical cells (CC) of Plocamium brasiliense, a marine macroalgae that synthesizes several halogenated monoterpenes. P. brasiliense specimens were submitted to a cytochemical analysis of the activity of the 3-hydroxy-3-methylglutaryl-CoA synthase (HMGS). Using transmission electron microscopy (TEM), we confirmed the presence of HMGS activity within the Mev. Because HMGS is necessary for the biosynthesis of halogenated monoterpenes, we isolated a hexanic fraction (HF) rich in halogenated monoterpenes from P. brasiliense that contained a pentachlorinated monoterpene as a major metabolite. Because terpenes are often related to chemical defense, the antifouling (AF) activity of pentachlorinated monoterpene was tested. We found that the settlement of the mussel Perna perna was reduced by HF treatment (2.25 times less than control; 40% and 90% of fouled surface, respectively; P = 0.001; F9,9 = 1.13). The HF (at 10 μg · mL(-1) ) also inhibited three species of fouling microalgae (Chlorarachnion reptans, Cylindrotheca cloisterium, and Exanthemachrysis gayraliae), while at a higher concentration (50 μg · mL(-1) ), it inhibited the bacteria Halomonas marina, Polaribacter irgensii, Pseudoalteromonas elyakovii, Shewanella putrefaciens, and Vibrio aestuarianus. The AF activity of P. brasiliense halogenated monoterpenes and the localization of HMGS activity inside Mev suggest that this cellular structure found in CC may play a role in thallus protection against biofouling.

The bluefish, Pomatomus saltatrix (Linnaeus, 1766), was used as a species-specific model to study morphometric relationships between otolith size and relative growth variables. Length-weight relationships between Otolith (Length-OL, Height-OH, and Weight-OW) and fish measurements (Total Length-TL and Total Weight-TW) were determined for fishes captured monthly during the year 2015 off the southeastern coast of Brazil. The ANCOVA and Kruskal-Wallis analysis did not indicate significant differences in the relative growth constants between sexes and length frequency distributions (p > 0.05). The condition factor also did not present significant differences between sexes, and right and left otolith measurements (p > 0.05). A total of 398 specimens were sampled: TL = 43.6-67.0 cm, TW = 365-2400 g, OL = 9.65-15.25 mm, OH = 3.65 - 5.45 mm and OW = 0.03-0.11 g. The LWR for grouped sexes was TW = 0.050TL2.55 and otoliths OW = 6.17E-05OL2.59. The best adjustments were TL vs OL (r2 = 0.90); OL vs OW (r2 = 0.90); TW vs OW (r2 = 0.81); and TW vs OL (r2 = 0.80). These results showed that such relationships are helpful tools for predicting the fish size and weight from otoliths, which may be used in food habits and paleontology studies, and other fisheries management applications.

The bluefish, Pomatomus saltatrix (Linneus 1766) is captured by industrial, artisanal, and recreational fisheries throughout its distribution range. The reproductive biology of P. saltatrix in the southwestern Atlantic was studied using 1,102 specimens captured by the Brazilian commercial fleet between March 2014 and December 2015. The recruitment period was identified from records of juveniles in experimental beach seine hauls carried out on sandy beaches in the external sector of Guanabara Bay for four years (2012–2015). Based on the reproductive indices and on the macro- and microscopic analyses of the gonads, spawning peaks were identified in autumn and spring. The size at first maturity was estimated at 35.5, 38.3, and 37.4 cm for females, males, and general, respectively. Ovary analyses and measurements of the oocyte diameters indicated that bluefish are multiple spawners with asynchronous oocyte development. The batch fecundity estimate was 202,752.5 eggs and ranged from 9,800.9 to 426,787.0 eggs. The species reproduces throughout the entire study area, but it is more active in the south of Arraial do Cabo. The young-of-the-year were recorded on shallow water in all seasons, with modal peaks in the summer months. The parameters estimated in this study expand and update information on this species, providing important data for the evaluation and fisheries management of the stock of P. saltatrix in the southwestern Atlantic.

O objetivo deste trabalho foi apresentar o diagnóstico da frota de cerco em operação no Sudeste e Sul do Brasil, caracterizando o acesso formal das embarcações, bem como a oferta de matéria-prima ao mercado. A frota autorizada foi analisada por meio do número de embarcações por modalidade de permissionamento e pelas características físicas das embarcações em 2020. A oferta de matéria-prima foi avaliada pelos dados referentes aos anos 2018 e 2019 do monitoramento pesqueiro, executado no Rio de Janeiro, Santa Catarina e São Paulo. As atividades da frota de cerco e o escoamento da matéria-prima para o mercado estão concentradas nos estados do Rio de Janeiro e Santa Catarina. Na última década, a frota de cerco foi significativamente expandida, com maior impacto sobre a sardinha-laje (Opisthonema oglinum) como espécie-alvo, especialmente em Santa Catarina. Essa frota apresenta capacidade de pesca menor do que a da frota autorizada para a sardinha-verdadeira (Sardinella brasiliensis), que cresceu em menor intensidade. Diante da redução da captura da sardinha-verdadeira, os principais recursos explorados foram a sardinha-laje, em Santa Catarina, e a sardinha-boca-torta (Cetengraulis edentulus), no Rio de Janeiro. O excesso de capacidade de pesca e o uso desordenado de recursos alternativos geram preocupação quanto à manutenção dos estoques e da cadeia produtiva.