The selectivity of gillnets for the inhabiting forage fish community in the Santa Cruz Channel (PE, Brazil) was estimated an experiment using three mesh sizes (30, 40 and 50 mm). The SELECT was used to estimate retention curves through four models: normal location, normal scale, lognormal and gamma. Aggregated as catches in all fisheries, 28 species were identified. Selectivity parameters for species Opisthonema oglinum, Anchovia clupeoides and Cetengraulis edentulous were estimated. The normal scale model gave the best fit for all species studied. In the case of O. oglinum fishing in the Santa Cruz Channel the catches of young individuals are particularly significant in gillnets with a 30 mm mesh size. However, a possible increase in mesh size indicates little change in the length structure of the catch for larger sizes, but catches would certainly be reduced. Thus, regulations with increased mesh size should result in non-viability of fishing continuity with reduced catches.

The purpose of this paper was evaluate the palatability of the meat of tambaqui of different ages and environments, both from natural and cultivated systems. In order to carry out the consumers' acceptability test concerning the tambaqui meat from different feeding, 14 wild fish and 14 cultivated ones were used, with average weight ranging from 0.8 to 8.5 kg, already killed, cut and fresh. The samples were separated according to the environment (wild and cultivated), stored in thermal box and processed as standard fried ribs. The total of 200 untrained tasters of both genders was consulted, with the intention of finding the common public's opinion. The evaluated items were: flavor, color, smell and texture. The samples from pisciculture obtained better acceptability results regarding young fish's meat (63.5%), and the adult's (78.0%), as compared to the same age groups for the natural environment fish with 49.7% and 61.0% of the total evaluated, respectively. Thus, the sensorial analysis demonstrated a greater preference for cultivated tambaqui's meat, with emphasis on the items flavor and texture, which can be attributed to feeding quality (fish food with 28% of crude protein) and husbandry employed in the farming system

Dinâmica da pesca de peixes pelágicos de pequeno porte no estuário do canal de Santa Cruz (Pernambuco-Brasil) Dynamics of fishing small pelagic fish in the Santa Cruz canal estuary (Pernambuco-Brazil

A type of dredge was introduced as fishing gear along the extractive bank of Mangue Seco - PE from which the largest annual catch of Anomalocardia flexuosa in the world is extracted. This study was carried out with the objective of estimating the selectivity of the new fishing gear and quantitatively evaluating the length classes most compromised by the catches, especially considering 20 mm as the reference value. Specimens larger than this size are most likely to be mature. For the selectivity estimation, the methodology using codends (16 or 20 mm) and small meshed cover (2 mm) was used. To estimate the selectivity parameters, a logistic regression and the Bayesian approach were used. The transition between the state in which the specimen is invulnerable to the fishing gear and vulnerable occurs between 10 and 18 mm, using a 16 mm mesh, and using a 20 mm mesh, this transition is between 14 and 20 mm. Dredgers with 16 mm and 20 mm mesh compromise a large proportion of specimens smaller than 20 mm. If the intention is to protect this part of the population, measures such as total restriction of the 16 mm mesh and use of the 20 mm mesh should be necessary only in the months of less catching incidences, or increasing the mesh to 25 mm.

This research analyzed the biometrics and reproductive characteristics of a group of Hypancistrus sp. L-333 (King Tiger Plecos) in order to gather biological information and aid the rearing of the species in captivity, thus supporting its natural conservation. This species has a natural distribution that is restricted to the lower Xingu River, and is currently threatened by the hydroelectric projects in the region. The acquired specimens were measured, weighed and classified according to sex based on morphometric characteristics (evidence of secondary sexual characteristics) that were later confirmed by dissection. A total of 32 individuals, 16 males and 16 females were identified. Although the length-weight ratio did not present significant differences, the results revealed that the species has secondary sexual dimorphism. The odontodes were more developed in the mid-lateral region of the body, post-dorsal region, caudal peduncle and in the first ray (ossified) of the pectoral fin in males. Histological analyses of the gonads confirmed that all of the fish were adult individuals. The diameter of the oocytes ranged from 0.14 to 2.0 mm, presented three distinct modes, and were synchronous in more than two groups, which evidences batch spawning. Fecundity was low, between 35 and 54 oocytes in the largest batch. This information is novel and important for the identification of reproductive groups, and is aimed at breeding in captivity so that these resources can be exploited in a sustainable way, without harming the already threatened natural stocks.