Análise Da Frota Pesqueira Artesanal Da Comunidade Da Raposa, São Luis, Ma

The artisanal fishery fleet of Rapôsa, Brazil, (lat: 2° 24\' S; long: 44° 04\' W) was surveyed from November 1987 to August 1988. This is the principal fishing community on the coast of Maranhão with 194 boats representing the potential fishing effort and 27 others engaged in transport activities. This fleet may be classified according to its length hull and propulsion characteristics. Four strata were defined in this fleet: 1 - Canoes with open "biana" hull and "bianas" sailing rig; 2 - Canoes with open "biana" hull and "curicaca" sailing rig; 3 - Flush decked "biana" and motor powered boats with less than 40 HP; and 4 - Motor powered boats with more than 40 HP. The hull length and the net length are suggested as fishing power measures for the evaluation of fish resources exploited by the Raposa fleet, particularly: Scomberomorve brasiliensis, Macrodon ancylodon and Cynoscion acoupa.Entre novembro de 1987 e agosto de 1988, realizou-se um censo da frota artesanal da Rapôsa, principal comunidade pesqueira do litoral maranhense. Esta frota está composta por 221 embarcações) das quais 186 operam na pesca. É uma frota estruturalmente heterogênea, segundo o tipo de casco e o tipo de propulsão. As variações dos diferentes tipos, são representáveis pelo comprimento do barco. Definiram-se 4 estratos dentro desta frota, que são1. Bianas abertas com vela biana; 2. 3iana aberta com vela curicaca; 3. Guanas fechadas e botes com potência de motor menor de 40 HP e 4. Botes com mais de 40 HP. As possíveis medidas de poder de pesca são o comprimento da embarcação e o comprimento de rede, as quais servirão de base para avaliação dos recursos pesqueiros explorados pela frota analisada, principalmente Scomberomorus brasiliensis, Macrodon ancylodone Cynoscion acoupa

Hacia un manejo pesquero integral en la cu enca del Río Apure, Venezuela

The goal of this study was to make recommendations to the fishery resource management in western savannas of Venezuela. We propose a new approach for sustainable development of hydrobiology resources, using precautionary, adaptive, ecosystem and co-management ideas adjusted to current economic, social, and cultural traditions, and put them into action through pilot projects at different scales. In Venezuela, although fisheries have a considerable history, ecology, fishery and economic fisheries management tools have seldom been applied to tools of inland fisheries management. Any fisheries management plan for the Apure River drainage, must have a set of strategies and tactics O objetivo deste trabalho e recomendar acoes para a ordenacao dos recursos pesqueiros nas Planicies Ocidentais da Venezuela, procurando seu desenvolvimento sustentável, a traves de novos enfoques (precautorio, adaptativo, ecossistemico e manejo participativo), ajustando os interesses economicos sociais e culturais da sociedade, com o uso dos recursos hidrobiologicos mediante projetos pilotos pontuais em diferentes escalas. Na Venezuela, a pesar de ter uma consideravel trajetoria pesqueira, escassamente tem sido utilizadas ferramentas ecologicas, economicas ou pesqueiras, para o manejo das pesqueiras continentais. Portanto, um planejamento do manejo pesqueiro para a bacia do rio Apure, deve compreender um for implementation, to guarantee the protection, conservation, and propagation of the fisheries resources, for both migratory or non-migratory fishes. To that end we suggest a set of directives needed to implement a hybrid fisheries management system in the Apure Basin that incorporates the advantages of adaptive management and participatory co-management using synchronic management. In Venezuela the institutional and legal framework already exists to implement effective fisheries management, but political will to is lacking too bring fishermen, managers and research scientists together to make sustainable fisheries management a reality in the Apure Basin

Reproductive biology of Tambaqui, Colossoma macropomum Cuvier, 1818 (Teleostei, Serrasalmidae), in the lower Amazon, Brazil

This study analysed the reproductive biology of the tambaqui Colossoma macropomum in the Lower Amazon. 1232 individuals were collected from October 1994 to February 1996 from landings in Santarém in Pará State. Individuals between 20 and 120cm total length were weighted, measured, sexed and classified according to their maturity stage. Fecundity and spawning type were determined to analysing intra-ovarian oocytes of 10 adult females. Colossoma macropomum is a total spawner. There are changes at different levels: macro and microscopic cycles according to hydrological periods. Mature individuals occurred between november and february, indicating that spawning take place during this period, at the beginning of flood. The sexual rate changes with the size of fishes. Males are more frequent between 40 and 75cm, and the females between 80 and 115cm. The length/weight relationship indicates differences in the growth between males and females. The average fecundity was estimated on 1.007.349 eggs per female. There is a significant relationship between fecundity and total weight. The equation founded to tambaqui in the Lower Amazon was F = 885347 + 9,16 W1.Analisaram-se aspectos da biologia reprodutiva do tambaqui (Colossoma macropomum) na região do Baixo Amazonas. Foram coletados 1232 exemplares entre outubro de 1994 e fevereiro de 1996, nos mercados e frigoríficos de Santarém no Estado do Pará. Indivíduos entre 20 e 120 cm foram pesados, medidos e observados o sexo e o estágio de maturidade. O tipo de desova e a fecundidade foram determinados através da análise dos ovócitos intraovarianos de 10 fêmeas maduras. Colossoma macropomum possui desova total. Existem variações macro e microscópicas cíclicas dos ovários associadas ao período hidrológico. A desova coincidiu com o início do período das chuvas. A proporção sexual varia com o tamanho dos peixes. A relação comprimento/peso indica diferenças nas estratégias de crescimento para ambos os sexos. O menor macho sexualmente maduro mediu 62 cm e o maior 95 cm, no caso das fêmeas, 70 cm e 112 cm respectivamente. A fecundidade média absoluta calculada para o tambaqui foi de 1.007.349 ovócitos (s = 67.279). Existe uma relação linear entre a fecundidade (F) e o peso total (W1) sendo a equação F = 885347 + 9,16 W1

Estimation of growth parameters of five fish species (Actinopterygii) caught in the central Amazon

For some tropical fishes, the information on growth parameters is still scarce, and few or no records are available in FishBase. Therefore, the objective of this study was to estimate the growth curves for Brycon amazonicus (Spix et Agassiz, 1829), Piaractus brachypomus (Cuvier, 1818), Prochilodus nigricans Spix et Agassiz, 1829, Semaprochilodus insignis (Jardine, 1841), and Semaprochilodus taeniurus (Valenciennes, 1821), and to build the auximetric plots for each of the families to which these species belong: Characidae, Prochilodontidae, and Serrasalmidae. Samples were obtained from commercial catches landed in the Port of Manaus. Growth parameters were estimated using the Electronic Length Frequency Analysis (ELEFAN) routine of the Length Frequency Distribution Analysis (LFDA) program. Twenty-six sets of growth parameters were thus estimated, and 66 further sets were located in the literature and FishBase. Prochilodontidae and Serrasalmidae showed a strong inverse relation between the variables composing the auximetric plots. © 2018, Scientific Society of Szczecin. All rights reserved

Plasticity in the shape and growth pattern of asteriscus otolith of black prochilodus Prochilodus nigricans (Teleostei: Characiformes: Prochilodontidae) freshwater Neotropical migratory fish

ABSTRACT Using morphometric measurements and wavelets functions, the asterisci otoliths of curimatã, Prochilodus nigricans were analysed to identify the variation in shape and growth increment of individuals from Solimões, Japurá and Negro rivers of the Amazon basin, Brazil. The morphometric and morphological analyses did not reveal evidences of population segregation among rivers, but variations were found in the estimation of otolith growth increment. Also, the otolith shape showed a high variability between individuals, identifying four morphotypes. Morphotype 1 shows a more oval shape with a posterior zone clearly rounded; Morphotype 2 shows the posterior zone rounded, but the anterior end is more elongated; Morphotype 3 shows a completely different shape, elliptic-pentagonal and Morphotype 4 shows the posterior zone rounded, but the anterior end is more elongated and it is the pattern with antirostrum and rostrum more pointed and a deep notch. Therefore, the otolith shape exhibited a phenotypic plasticity that it was not associated with the metabolism of otolith growth. Whereas the otolith shape indicated a homogeneity in the sound perception through Amazon basin, the growth rates revealed an adaptive mechanism to environmental conditions or migratory process of this species.</div

Annulus formation on scales and seasonal growth of the Central Amazonian anostomid Schizodon fasciatus

Annulus formation on the scales of the Central Amazonian anastomid fish Schizodon fasciatus was studied with respect to periodic variations in growth rates caused by seasonal inundation or associated biological processes. Monthly samples from fish markets were analysed with regard to marginal scale increment, feeding index, condition factor, gonadosomatic index, and body cavity fat content. There was a significant variation in all indices which was related to seasonal change in water level. Fat storage was related to energy requirements especially during gonad maturation. Fastest growth was observed during the period of falling water level. The formation of scale growth marks corresponded to the period of gonad maturation between January and February. The results indicate the formation of only one single growth mark on scales per year

Landscape variables affecting fishery yield in lake systems of the Central Amazon region, Brazil

According to fisheries data, lakes are important systems for fish production in the Amazon basin. However, there is no information about the relationship between landscape variables and fishing yield that allows foresight into potential resource exploitation in this environment. The present study aims to evaluate this relationship with the hypothesis: lakes of different shapes give the same fishery yield in the Amazon, after considering the effects of lake size, distance to the river, fishing effort, fuel and ice used. Fishery data from 1994 to 1996 were analyzed with regard to 3228 trips on 50 lakes of the main white water tributaries of the Amazon basin. Analysis of covariance was applied to test this hypothesis. With variables such as fishing grounds access, fishing effort and lake shape the model explained a significant 72% of variabilities in the fisheries yield. Fishing yields among lake systems were different, thus the null hypothesis was rejected (P < 0.05). Results indicate that dendritic lakes far distant from the main river have greater productivity than floodplain lakes because there are more habitats of fish refuge for reproduction and feed available to the fish; there are also more limitations to access by predators. © 2008 Blackwell Verlag

Fish communities in central Amazonian white- and blackwater floodplains

In Amazonian floodplains, the flood cycle of the river is becoming the dominant season al factor, and fish communities are found to fluctuate greatly over the year. During inundation, fish migrate into floodplain forests to feed on fruits and seeds, in an area more than 300 000 km2 in size. To document patterns of species diversity, distribution, abundance and temporal dynamics and in order to describe the ecological importance of the inundated forest, floodplain fish were captured using variously sized gill nets in white and black water areas inside and outside the floodplain forests during low, rising, high and falling water level in 1990 and 1991. Dominance varies to some extent in white water between floodplain forest (0.06) and open water (0.11) while it is unchanged in black water (0.04). Black water fish communities were more diverse. Most abundant among white water fish were Liposarcus pardalis, Pygocentrus nattereri, and Pellona flavipinnis, for example, or Plagioscion squamosissimus, Serrasalmus rhombeus, and Serrasalmus manueli in black water. Among the most abundant white water fish, Colossoma macropomum, Mylossoma duriventre and Osteoglossum bicirrhosum occurred almost exclusively in inundated forests. Of the black water species there were a large number of species which were captured only in inundated forest, such as Geophagus cf. altifrons, Hoplias malabaricus, Osteoglossum bicirrhosum and Uaru amphiacanthoides. Catches varied with sample site, water level and direction of water level change. The average CPUE in white and black water was 190 and 41 g fish m-2 and day, respectively, with maximum yields at low water and minimum yields at high water. Comparing rising and falling water levels, a significantly higher quantity of fishes was captured at falling water level. In black water, fish catches from the floodplain forest exceeded the open water catch by 183 to 550%, depending on season. Differences in respect of white water are smaller (106-281%). Fish communities in the area under investigation seem to be stochastically assembled, with significant differences between white and black water only. Many fishes move into the floodplain forest not only to feed but probably also for other reasons to seek shelter, for example