SABIIA - Sistema Aberto e Integrado de Informação em Agricultura (Sabiia)

Oliveira,Valéria de Albuquerque; Fontoura,Nelson Ferreira; Montag,Luciano Fogaça de Assis.

The present study analyzed the length-weight relationship and some aspects of the reproductive biology of Anableps anableps from the mouth of the Maracanã River, in the Brazilian state of Pará. The specimens were collected using two 30 m-long gillnets with 15 and 20 mm mesh size, as well as a 1 m-diameter hand net with a 10 mm mesh. A total of 865 specimens were collected, from which an adult sex ratio of 2.12 females per male was recorded (χ² = 13.07; p<0.05). Females presented positively allometric growth, whereas males were negatively allometric. In the additional analyses, the gonads of 371 female specimens were observed microscopically. Gonadal development was classified in three stages: immature (5.0%), maturing (12.0%), and mature (83.0%)....

Predicting size at first sexual maturity from length/weight relationship: a case study with an Amazonian catfish

Palavras-chave: "Four-eyed" fish; Reproduction; Viviparity.

Ano: 2011

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252011000400007

Freitas,Tiago Magalhães da Silva; Almeida,Vitor Hudson da Consolação; Montag,Luciano Fogaça de Assis; Fontoura,Nelson Ferreira.

ABSTRACT Relationship between length and weight (LWR) is used to describe aspects concerning the life cycle of fish, but does not considers possible changes during the lifetime mainly due to the sexual maturation. Thus, this study aims to identify the size at first maturity of Auchenipterichthys longimanus (Siluriformes: Auchenipteridae) and infer if the reproductive engagement could change growth pattern, concerning the LWR. Estimates of the size at first maturity (L 50 ) were made by visual identification of gonadal development and through the gonadosomatic index (G SI ). L 50 was estimated as 12.5 cm for males and 13.0 cm for females when applied visual identification of gonads development. L 50 estimates increased to 13.05 cm for males and 13.7 cm...

Seasonal changes in the gonadossomatic index, allometric condition factor and sex ratio of an auchenipterid catfish from eastern Amazonia

Palavras-chave: Amazonia; Auchenipteridae; Fish reproduction; Growth pattern; Sexual maturity.

Ano: 2016

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252016000400203

Freitas,Tiago Magalhães da Silva; Almeida,Vitor Hudson da Consolação; Montag,Luciano Fogaça de Assis; Rocha,Rossineide Martins da; Fontoura,Nelson Ferreira.

The aim of the present study was to evaluate the seasonal pattern of the gonadosomatic index (GSI), condition factor (K), and sex ratio in the catfish Auchenipterichthys longimanus (Siluriformes: Auchenipteridae) as an approach to identify its reproductive period. A total of 589 A. longimanus specimens (251 males and 338 females) were captured in the rivers of the Caxiuanã National Forest, in the Brazilian state of Pará, between July, 2008 and July, 2009. Among the male specimens, 171 were classified as adults and 80 as juveniles, while there were 249 adults and 89 juvenile females. Using a sinusoidal equation, analysis of the GSI revealed a reproductive asynchrony between the genders, with males attaining their highest GSI values in January, while females...

Feeding ecology of immature Lithodoras dorsalis (Valenciennes, 1840) (Siluriformes: Doradidae) in a tidal environment, estuary of the rio Amazonas

Palavras-chave: Auchenipterichthys longimanus; Hydrological seasons; Reproduction; Siluriformes.

Ano: 2011

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252011000400015

Barbosa,Thiago Augusto Pedroso; Barthem,Ronaldo Borges; Montag,Luciano Fogaça de Assis.

Studies of feeding ecology are important for the evaluation of interactive processes in fish communities. This study evaluated the feeding ecology of Lithodoras dorsalis (Doradidae) from streams within the Amazon estuary delta (Brazil), a macro-tidal area, on different pluviometric periods. A total of 371 young specimens was collected during 12 months of sampling (July 2010 to June 2011). The species diet was composed of 28 food items analyzed by Repletion Index, Alimentary Index and Niche Breadth. Young L. dorsalis was classified as herbivore with a frugivory tendency due to the high importance of fruit and seeds in its diet. Food intake varied among sampled months, with the lowest intake being recorded during the rainy-dry season transition period, and...

Feeding ecology of Auchenipterichthys longimanus (Siluriformes: Auchenipteridae) in a riparian flooded forest of Eastern Amazonia, Brazil

Palavras-chave: Diet; Doradidae; Feeding Index; Rock-bacu; Thorny catfish.

Ano: 2015

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252015000200341

Freitas,Tiago Magalhães da Silva; Almeida,Vitor Hudson da Consolação; Valente,Roberta de Melo; Montag,Luciano Fogaça de Assis.

Feeding habits of the midnight catfish Auchenipterichthys longimanus collected in rivers of the Caxiuanã National Forest (Eastern Amazonia, Brazil) were investigated through the different hydrological periods (dry, filing, flood and drawdown). A total of 589 specimens were collected throughout seven samplings between July 2008 and July 2009, of which 74 were young males, 177 adult males, 89 young females and 249 adult females. The diet composition (Alimentary index - Ai%) was analyzed by a non-metric multidimensional scaling (nMDS) and by the analysis of similarity (ANOSIM), which included 37 items grouped into nine categories (Aquatic insects, Other aquatic invertebrates, Arthropods fragment, Fish, Plant fragment, Seeds, Terrestrial insects, Other...

Spatial and temporal variation of the diet of the flag tetra Hyphessobrycon heterorhabdus (Characiformes: Characidae) in streams of the Eastern Amazon

Palavras-chave: Amazon; Catfish; Hydrological seasons; Trophic ecology.

Ano: 2011

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252011000300016

Benone,Naraiana Loureiro; Lobato,Cleonice Maria Cardoso; Soares,Bruno Eleres; Montag,Luciano Fogaça de Assis.

ABSTRACT Spatial and temporal variations in streams promote large fluctuations of resource availability, thus affecting the diet of fishes. We evaluated the effects of hydrological periods and stream order within periods on the diet of the flag tetra Hyphessobrycon heterorhabdus. We analyzed 160 stomachs in eight streams ranging from 1st to 3rd order between dry and flood period. Sampled streams belonged to a well-preserved area in the Eastern Amazon. The flag tetra is omnivorous, with a tendency towards insectivory. During the dry period, the species exhibited a higher amount of autochthonous than allochthonous items. Fish consumed more allochthonous items in 1st and 2nd order streams in the dry period and in 1st and 3rd order streams in the flood period....

Population and reproductive parameters of the red-tailed catfish, Phractocephalus hemioliopterus (Pimelodidae: Siluriformes), from the Xingu River, Brazil

Palavras-chave: Feeding; Floodplain; Hydrological period; Riparian vegetation; Stream order.

Ano: 2020

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252020000400206

Freitas,Tiago Magalhães da Silva; Montag,Luciano Fogaça de Assis.

ABSTRACT A field study of the sex ratio, length-weight ratio, body size at first gonadal maturation, and the breeding season of the red-tailed catfish, Phractocephalus hemioliopterus, was carried out in the region of the middle Xingu River in the eastern Amazon basin. The fish were sampled quarterly from September 2012 to January 2014 using gillnets and long lines. The sex ratio was balanced, and while males and females were similar in standard length, the females were heavier than the males, on average. The males presented negative allometric growth, and the females, isometric growth. The estimated size at first maturity was 77.8 cm. The variation in the gonadosomatic index and the greater frequencies of mature specimens indicated a reproductive peak at...

Ecomorphological patterns of the fishes inhabiting the tide pools of the Amazonian Coastal Zone, Brazil

Palavras-chave: Amazon basin; Breeding season; Fishery; Gonadal maturity; Growth pattern.

Ano: 2019

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252019000200216

Soares,Bruno Eleres; Ruffeil,Tiago Octavio Begot; Montag,Luciano Fogaça de Assis.

The present study was based on the identification of the ecomorphological patterns that characterize the fish species found in tide pools in the Amazonian Coastal Zone (ACZ) in the Pará State, Brazil. Representatives of 19 species were collected during two field campaigns in 2011. The dominance, residence status, and trophic guild of each species were established, and morphometric data were obtained for up to 10 specimens of each species. A total of 23 ecomorphological attributes related to locomotion, position in the water column, and foraging behavior were calculated for the analysis of ecomorphological distance. Principal Component Analysis (PCA) was utilized for the evaluation of ecomorphological attributes that explained the variation among species....

Edge effects and the impact of wildfires on populations of small non-volant mammals in the forest-savanna transition zone in Southern Amazonia

Palavras-chave: Ecomorphology; Habitat use; Resource partitioning; Intertidal zone; Estuaries.

Ano: 2013

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013000400845

Mendes-Oliveira,Ana Cristina; Santos,Paulo Guilherme Pinheiro dos; Carvalho-Júnior,Oswaldo de; Montag,Luciano Fogaça de Assis; Lima,Renata Cecília Soares de; Maria,Suzanne Lúcia Silva de; Rossi,Rogério Vieira.

The impact of fire and edge effects on the community of small non-volant mammals was investigated in transitional Amazon forest within a matrix of soybean plantations. The animals were live trapped on 24 line transects, of which 16 were distributed in unburned areas and 8 in a burned area. A total of 11 species was recorded, including six rodents and five marsupials. The abundance and richness of small mammals appeared to decrease in burned areas, although this impact appeared to mask edge effects. In the absence of fire impacts, a positive relationship was found between mammal abundance and the distance from the forest edge. The impact of the edge effect on the diversity of small mammals appears to be influenced by the type of anthropogenic matrix and the...

Feeding ecology of Dash-dot Tetra Hemigrammus belottii(Steindachner 1882) (Characiformes: Characidae) in the streams of the Urucu River basin, central Amazonia, Brazil

Palavras-chave: Cricetidae; Didelphidae; Diversity; Soybean matrix; Experimental fire.

Ano: 2012

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032012000300004

Gonçalves,Andrey Felipe Gomes; Prudente,Bruno da Silveira; Carvalho Filho,Fernando da Silva; Montag,Luciano Fogaça de Assis.

The present study describes aspects of feeding ecology of Dash-dot TetraHemigrammus belottii (Characiformes: Characidae) collected in the Urucu River basin in Coari, Amazonas (Brazil), aims to respond the following question: What is the influence of hydrological periods (dry and wet) and spatial distribution in the diet of H. belottii? The specimens were collected between 2006 and 2009 in seven streams in the Urucu basin using standard capture methods. Their stomachs were removed for diet composition analyses. The alimentary items were weighed and identified for subsequent analyzes related to feeding intensity by repletion index (RI%) and importance by alimentary index (AIi%). A total of 227 specimens were analyzed, with a mean standard length of 16.5±5.6...

Ictiofauna de campos alagados da Ilha do Marajó, Estado do Pará, Brasil

Palavras-chave: Allochthonous item; Amazon basin; Trophic ecology.

Ano: 2013

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032013000300141

Montag,Luciano Fogaça de Assis; Albuquerque,Adna Almeida de; Freitas,Tiago Magalhães da Silva; Barthem,Ronaldo Borges.

Os campos alagados ou savanas da ilha do Marajó é uma área disjunta do bioma Cerrado na Amazônia, e é considerada de grande importância para planos de manejo, conservação e preservação ambiental. A fim de ampliar o conhecimento ictiofaunístico da região, o presente estudo reuniu informações coletadas em campo, compiladas da literatura e selecionadas de coleções ictiológicas sobre a fauna de peixes da eco-região savana do Marajó. As coletas de campo ocorreram entre os anos de 2003 e 2005, e apresentaram como métodos a rede de mão, rede de arrasto, rede de tapagem e captura manual por técnica de mergulho, sendo que durante esse período foram amostrados os municípios de Ponta de Pedras, Chaves e Muaná. Além desses, outros quatro municípios também foram...

Length-weight relationship and reproduction of the guppy Poecilia reticulata (Cyprinodontiformes: Poeciliidae) in urban drainage channels in the Brazilian city of Belém

Palavras-chave: Peixes; Biodiversidade; Savana; Bacia Amazônica.

Ano: 2009

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032009000300024

Montag,Luciano Fogaça de Assis; Freitas,Tiago Magalhães da Silva; Raiol,Roberta Dannyele de Oliveira; Silva,Marlene Vasconcelos da.

This paper describes the length-weight relationship, size at first maturation (L), and breeding season of Poecilia reticulata found in drainage channels on the campus of the Federal University of Pará (UFPA) in the Brazilian city of Belém. A total of 1.936 specimens (942 males and 994 females) were collected in monthly samples of the study area between June, 2006, and March, 2007. Females were significantly longer and heavier than males. The length-weight relationship for males was established by the equation Pt = 5 × 10-5 × Ct2.397 and for females by Pt = 3 × 10-6 × Ct3.419. The estimated value of L was 17.5 mm for males and 20.4 mm for females, suggesting that males initiate reproductive activity at a smaller size than females. The abundance of mature...