Peces del oriente de Antioquia, Colombia

The eastern Antioquia region of Colombia's central mountain range, is characterize by steep altitudinal gradients and rich hydrological resources, with the majority of the drainage flowing into the middle Magdalena River. To compile a taxonomic list of the fish of eastern Antioquia, three sources of information were used: i) the revision of unpublished literature available in regional libraries, ii) revision icthyological collections with vouchers of the region, and iii) specific field work in unstudied aquatic systems. A total of 103 species belonging to eight orders and 25 families were found. The majority of the species found belonged to the families Characidae, Astroblepidae, Loricariidae and Trichomycteridae. Of the species collected, 32 are new records for the region and four are apparently new to science. Eight exotics species are introduced, now established in natural systems. With this study the total for the region increased considerably above the 49 species that had been previously reported in literature, much of which is from the 1980's. It is important to increase collecting efforts in the eastern Antioquia region, due to the underestimation of it's fish biodiversity

Peces del oriente de Antioquia, Colombia

The eastern Antioquia region of Colombia's central mountain range, is characterize by steep altitudinal gradients and rich hydrological resources, with the majority of the drainage flowing into the middle Magdalena River. To compile a taxonomic list of the fish of eastern Antioquia, three sources of information were used: i) the revision of unpublished literature available in regional libraries, ii) revision icthyological collections with vouchers of the region, and iii) specific field work in unstudied aquatic systems. A total of 103 species belonging to eight orders and 25 families were found. The majority of the species found belonged to the families Characidae, Astroblepidae, Loricariidae and Trichomycteridae. Of the species collected, 32 are new records for the region and four are apparently new to science. Eight exotics species are introduced, now established in natural systems. With this study the total for the region increased considerably above the 49 species that had been previously reported in literature, much of which is from the 1980's. It is important to increase collecting efforts in the eastern Antioquia region, due to the underestimation of it's fish biodiversity.La región del Oriente de Antioquia, ubicada en la cordillera Central de Colombia, se caracteriza por un amplio gradiente altitudinal, presentando gran riqueza hídrica, donde la mayoría de sus cuencas drenan hacia la cuenca media del río Magdalena. Con el objetivo de elaborar un listado taxonómico actualizado de los peces del Oriente de Antioquia, se usaron tres fuentes de información: i) revisión de la información disponible en bibliotecas regionales; ii) revisión de colecciones que tuvieran registros del área estudiada; iii) colectas puntuales en cuencas sin información previa. Se registran 103 especies pertenecientes a ocho órdenes y 25 familias. Las familias que presentaron la mayor riqueza fueron Characidae, Astroblepidae, Loricariidae y Trichomycteridae. De las especies colectadas 32 son registros nuevos para la región y aparentemente cuatro de ellas son nuevas especies. Ocho de las especies han sido introducidas y se encuentran en ambientes naturales. El número total de especies aumenta considerablemente el número registrado en la literatura recopilada (49 especies), siendo que la mayor parte de estos documentos fueron producidos en la década de 1980 a 1990. Es importante aumentar los muestreos en el oriente de Antioquia, pues su riqueza de peces ha sido subestimada

Checklist of the freshwater fishes of Colombia

Data derived from the literature supplemented by examination of specimens in collections show that 1435 species of native fishes live in the freshwaters of Colombia. These species represent 14 orders and 47 families. Orders with the largest numbers of species in the Colombian continental ichthyofauna are the Characiformes (637 species), Siluriformes (524 species), Perciformes (124 species), and Gymnotiformes (74 species), with the remaining 10 orders having from 1 to 35 species. At the family level, the Characidae has the greatest number of species (399 species), with this followed by the Loricariidae (166 species), Cichlidae (114 species), Pimelodidae (54 species), and Trichomycteridae (54 species); the remaining 42 families having 1 to 52 species. Present data indicate that 311 of the species occur solely at locations within Colombia. Continued descriptions of new species from the continental waters of Colombia demonstrate that the present total underestimates the species-level diversity of the ichthyofauna. The 1435 species living in Colombian freshwaters represent approximately 5% of all freshwater and marine fish species now recognized worldwide and approximately 29% of the freshwater fish species known to inhabit the drainages across the expanse from the southern border of Mexico through to Chile and Argentina. Various historical and ecological factors potentially contributing to the species-level richness of the Colombian freshwater fish fauna are discussed (e.g. geology, climate, physiography, water chemistry)

Peces de la cuenca del río Pauto, Orinoquia colombiana

This paper presents an updated list of the fishes of the Pauto river basin, Casanare. The update process was realized by collections in the field in the middle and lower part of the basin, revision of reference collections and secondary information available. A total of 182 species are recorded. Of these species, 60 are new records for the Pauto river basin. Only one species is included in the Red Book of freshwater fishes of Colombia. At the regional level, 52 species were identified as ornamental, and 24 are used as food; 8 species are exploited for both purposes. Based on the results, it is indispensable to re-evaluate the importance of the Pauto river basin as an area of interest for regional conservation

Peces de la cuenca del río Pauto, Orinoquia colombiana

This paper presents an updated list of the fishes of the Pauto river basin, Casanare. The update process was realized by collections in the field in the middle and lower part of the basin, revision of reference collections and secondary information available. A total of 182 species are recorded. Of these species, 60 are new records for the Pauto river basin. Only one species is included in the Red Book of freshwater fishes of Colombia. At the regional level, 52 species were identified as ornamental, and 24 are used as food; 8 species are exploited for both purposes. Based on the results, it is indispensable to re-evaluate the importance of the Pauto river basin as an area of interest for regional conservation.Se presenta un listado actualizado de los peces de la cuenca del río Pauto, departamento del Casanare (Colombia). La actualización se realizó mediante colectas en campo en la parte media y baja de la cuenca, así como la revisión de colecciones de referencia e información secundaria disponible. Se registran 182 especies. De éstas especies 60 corresponden a nuevos registros para la cuenca del río Pauto. Sólo una especie está incluida en el Libro Rojo de peces de agua dulce de Colombia. De las especies registradas 52 son consideras como especies ornamentales a nivel regional y 24 de importancia para consumo, ocho especies son explotadas con doble propósito. Basado en los resultados obtenidos es indispensable re-evaluar la importancia de la cuenca del río Pauto como área de interés para la conservación a nivel regional

Fragmentation of Andes-to-Amazon connectivity by hydropower dams

Andes-to-Amazon river connectivity controls numerous natural and human systems in the greater Amazon. However, it is being rapidly altered by a wave of new hydropower development, the impacts of which have been previously underestimated. We document 142 dams existing or under construction and 160 proposed dams for rivers draining the Andean headwaters of the Amazon. Existing dams have fragmented the tributary networks of six of eight major Andean Amazon river basins. Proposed dams could result in significant losses in river connectivity in river mainstems of five of eight major systems—the Napo, Marañón, Ucayali, Beni, and Mamoré. With a newly reported 671 freshwater fish species inhabiting the Andean headwaters of the Amazon (>500 m), dams threaten previously unrecognized biodiversity, particularly among endemic and migratory species. Because Andean rivers contribute most of the sediment in the mainstem Amazon, losses in river connectivity translate to drastic alteration of river channel and floodplain geomorphology and associated ecosystem services

Peces de la cuenca del río Orinoco. Parte I: Lista de especies y distribución por subcuencas

Para efectos del presente trabajo y en función de los datos disponibles hasta la fecha, se consideran las siguientes subcuencas y/o regiones para la cuenca del Orinoco, desde su nacimiento hasta su desembocadura en el océano Atlántico: Alto Orinoco, Casiquiare, Ventuari, Atabapo, Inírida, Guaviare, Vichada, Sipapo, Tomo, Cataniapo, Bita, Meta, Parguaza, Cinaruco, Suapure, Capanaparo, Arauca, Apure, Cuchivero, Manapiare, Zuata, Caura, Pao, Aro, Caris, Caroní, Morichal Largo, Delta y Orinoco (Mapa)

Review: Strategies for enteric methane mitigation in cattle fed tropical forages

Methane (CH4) is a greenhouse gas (GHG) produced and released by eructation to the atmosphere in large volumes by ruminants. Enteric CH4 contributes significantly to global GHG emissions arising from animal agriculture. It has been contended that tropical grasses produce higher emissions of enteric CH4 than temperate grasses, when they are fed to ruminants. A number of experiments have been performed in respiration chambers and head-boxes to assess the enteric CH4 mitigation potential of foliage and pods of tropical plants, as well as nitrates (NO3−) and vegetable oils in practical rations for cattle. On the basis of individual determinations of enteric CH4 carried out in respiration chambers, the average CH4 yield for cattle fed low-quality tropical grasses (>70% ration DM) was 17.0 g CH4/kg DM intake. Results showed that when foliage and ground pods of tropical trees and shrubs were incorporated in cattle rations, methane yield (g CH4/kg DM intake) was decreased by 10% to 25%, depending on plant species and level of intake of the ration. Incorporation of nitrates and vegetable oils in the ration decreased enteric CH4 yield by ∼6% to ∼20%, respectively. Condensed tannins, saponins and starch contained in foliages, pods and seeds of tropical trees and shrubs, as well as nitrates and vegetable oils, can be fed to cattle to mitigate enteric CH4 emissions under smallholder conditions. Strategies for enteric CH4 mitigation in cattle grazing low-quality tropical forages can effectively increase productivity while decreasing enteric CH4 emissions in absolute terms and per unit of product (e.g. meat, milk), thus reducing the contribution of ruminants to GHG emissions and therefore to climate change

A database of freshwater fish species of the Amazon Basin

The Amazon Basin is an unquestionable biodiversity hotspot, containing the highest freshwater biodiversity on earth and facing off a recent increase in anthropogenic threats. The current knowledge on the spatial distribution of the freshwater fish species is greatly deficient in this basin, preventing a comprehensive understanding of this hyper-diverse ecosystem as a whole. Filling this gap was the priority of a transnational collaborative project, i.e. the AmazonFish project - https://www.amazon-fish.com/. Relying on the outputs of this project, we provide the most complete fish species distribution records covering the whole Amazon drainage. The database, including 2,406 validated freshwater native fish species, 232,936 georeferenced records, results from an extensive survey of species distribution including 590 different sources (e.g. published articles, grey literature, online biodiversity databases and scientific collections from museums and universities worldwide) and field expeditions conducted during the project. This database, delivered at both georeferenced localities (21,500 localities) and sub-drainages grains (144 units), represents a highly valuable source of information for further studies on freshwater fish biodiversity, biogeography and conservation