Results 41 to 50 of about 246 (148)

Proposal of a non-lethal visual census method to estimate freshwater stingray abundance

Universitas Scientiarum, 2016
There is not a current method to estimate South American freshwater stingray’s abundance. Therefore we designed a census method and tested it in the field.
Mónica Andrea Morales-Betancourt, Carlos Andrés Lasso-Alcalá   +1 more
doaj   +1 more source

Trophic ecology and metabolism of two species of nonnative freshwater stingray (Chondrichthyes: Potamotrygonidae)

Hydrobiologia, 2020
The stingrays Potamotrygon amandae and Potamotrygon falkneri are nonnative species established in the Upper Parana basin. Although they are widely distributed, few studies on their diets or respective metabolic responses exist. Therefore, the aim was to evaluate the dietary composition, trophic niche breadth and lipid/protein concentrations in muscle ...
Cibele Diogo Pagliarini, Cristiéle da Silva Ribeiro, Lucas Spada, Rosilene Luciana Delariva, Jumma Miranda Araújo Chagas, Luciano Alves dos Anjos, Igor Paiva Ramos   +6 more
openaire   +3 more sources

SERUM COMPOSITION OF FRESHWATER STRINGRAYS (POTAMOTRYGONIDAE) ADAPTED TO FRESH AND DILUTE SEA WATER

The Biological Bulletin, 1973
1. Juvenile freshwater stingrays of the family Potamotrygonidae are unable to survive in salinities in excess of 20.6‰ when gradually acclimated.2. No differences were observed in blood pH or hematological parameters when fish adapted to a salinity of 14.5‰ were compared with freshwater controls.3. Significant increases were found in serum sodium (21%),
Griffith, Robert W, Pang, Peter K T, Srivastava, Anil K, Pickford, Grace E   +3 more
openaire   +2 more sources

Bioecología de la raya de agua dulce Potamotrygon magdalenae (Duméril, 1865) (Myliobatiformes) en la Ciénaga de Sabayo, Guaymaral, Colombia

Revista U.D.C.A Actualidad & Divulgación Científica, 2011
A pesar de la representatividad de Potamotrygon magdalenae en Colombia, por encontrarse a lo largo de la cuenca del río Magdalena y sus afluentes, esta raya no ha sido objeto de estudios previos, desconociéndose la mayor parte de sus aspectos bio ...
Herly Bibiana Ramos Socha, Marcela Grijalba Bendeck   +1 more
doaj   +1 more source

Ornamental fishing in the region of Barcelos, Amazonas: socioeconomic description and scenario of activity in the view of “piabeiros” [PDF]

Brazilian Journal of Biology, 2019
The Negro river basin is considered the largest area of extractive of ornamental fish in Brazil. This area has fundamental importance for the populations from the Amazon.
D. S. Ladislau, M. W. S. Ribeiro, P. D. S. Castro, P. H. R. Aride, A. J. V. Paiva, M. F. Polese, A. B. Souza, L. A. Bassul, H. D. Lavander, A. T. Oliveira   +9 more
doaj   +1 more source

DIVERSIDADE DE RAIAS DE ÁGUA DOCE (Chondrichthyes : Potamotrygonidae) NO ESTUÁRIO AMAZÔNICO

Arquivos de Ciências do Mar, 2008
Um levantamento sobre registros de ocorrência de raias de água doce (Potamotrygonidae) no estuário amazônico foi realizado utilizando-se dados  bibliográficos, informações de coleções científicas disponíveis on-line e amostragens de campo. Os resultados indicaram a presença de oito espécies nominais: Plesiotrygon iwamae, Paratrygon aiereba,Potamotrygon
Maurício Pinto De Almeida, Ronaldo Borges Barthem, Anderson da Silva Viana, Patrícia Charvet Almeida   +3 more
openaire   +1 more source

Spatiotemporal eDNA Monitoring of Marine Biodiversity in a Hyperurbanised Coastal Environment

Environmental DNA, Volume 7, Issue 4, July–August 2025.
Using environmental DNA and a metabarcoding approach, we amplified and sequenced the cytochrome oxidase subunit I (COI) gene for invertebrates and the 16S rRNA gene for vertebrates. Our spatiotemporal analyses over a year and across four sites in Singapore revealed distinct communities between sites and timepoints for both the COI and 16S rRNA assays ...
Zhi Ting Yip, Zheng Bin Randolph Quek, Danwei Huang   +2 more
wiley   +1 more source

Serum chemistry, thyroxine concentration, and blood cell morphology of wild, young Blackchin Guitarfish Glaucostegus cemiculus sampled on the eastern Mediterranean coastline

Journal of Aquatic Animal Health, Volume 36, Issue 3, Page 281-299, September 2024.
Abstract Objective The Blackchin Guitarfish Glaucostegus cemiculus is endemic to the Mediterranean Sea and is critically endangered, but relevant routine laboratory data are unavailable. Our objectives were to determine the packed cell volume (PCV), comprehensive serum chemistry analytes, and serum total thyroxine (sTT4) concentration; compare serum ...
Nevo Schwartz, Danny Morick, Barak Azrieli, Aviad Scheinin, Dan Tchernov, Itamar Aroch   +5 more
wiley   +1 more source

Aplicación del modelo de pérdida de ADN para el diseño de cebadores en Potamotrygon magdalenae (Potamotrygonidae)

Acta Biológica Colombiana, 2021
El diseño de cebadores es fundamental para amplificar regiones de genes debido a que la especificidad que mantienen cebador-secuencia de interés puede causar el éxito o fracaso en la reacción de PCR.
Iván Yesid López-Ardila, Francisco José Martínez-Pérez, Fernando Rondón-González   +2 more
doaj   +1 more source

Vulnerability of Eastern Tropical Pacific chondrichthyan fish to climate change

Global Change Biology, Volume 30, Issue 7, July 2024.
This assessment identifies sharks' vulnerability to climate change in a data‐poor tropical region and suggests management actions. Abstract Climate change is an environmental emergency threatening species and ecosystems globally. Oceans have absorbed about 90% of anthropogenic heat and 20%–30% of the carbon emissions, resulting in ocean warming ...
Florencia Cerutti‐Pereyra, Elizabeth J. Drenkard, Mario Espinoza, Brittany Finucci, Felipe Galván‐Magaña, Ana Hacohen‐Domené, Alexander Hearn, Mauricio E. Hoyos‐Padilla, James T. Ketchum, Paola A. Mejía‐Falla, Ana V. Moya‐Serrano, Andres F. Navia, Diana A. Pazmiño, Deni Ramírez‐Macías, Jodie L. Rummer, Pelayo Salinas‐de‐León, Oscar Sosa‐Nishizaki, Charles Stock, Andrew Chin   +18 more
wiley   +1 more source