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Valle del Guamuez, Colombia

The upper Cauca River valley (VARC) is considered a region of high diversity of waterbirds, due to the occurrence of different types of natural and artificial wetlands, the latter including reservoirs, lakes, ponds and rice fields. I document the occurrence of four duck species in some artificial wetlands located in Cauca and Valle del Cauca departments: Comb Duck, Yellow-billed Pintail, Green-winged Teal and Northern Pintail. These records are noteworthy because Knob-billed duck and Yellow-billed Pintail are considered threatened species in Colombia and are little studied; the record of Green-winged Teal is the first for the VGRC and the second one for Colombia. The Northern Pintail records are the most recent for this duck in Colombia. Documenting the records of these species is intended to attract interest to this group of waterbirds that need more information regarding their distributions in this country. © 2015, Asociacion Colombiana de Ornitologia. All rights reserved.

Morris-Pocock J.A.,Queens University | Steeves T.E.,University of Canterbury | Estela F.A.,Asociacion Calidris | Anderson D.J.,Wake forest University | Friesen V.L.,Queens University
Molecular Phylogenetics and Evolution | Year: 2010

To test the hypothesis that both physical and ecological barriers to gene flow drive population differentiation in tropical seabirds, we surveyed mitochondrial control region variation in 242 brown boobies (Sula leucogaster), which prefer inshore habitat, and 271 red-footed boobies (S. sula), which prefer pelagic habitat. To determine the relative influence of isolation and gene flow on population structure, we used both traditional methods and a recently developed statistical method based on coalescent theory and Bayesian inference (Isolation with Migration). We found that global population genetic structure was high in both species, and that female-mediated gene flow among ocean basins apparently has been restricted by major physical barriers including the Isthmus of Panama, and the periodic emergence of the Sunda and Sahul Shelves in Southeast Asia. In contrast, the evolutionary history of populations within ocean basins differed markedly between the two species. In brown boobies, we found high levels of population genetic differentiation and limited gene flow among colonies, even at spatial scales as small as 500 km. Although red-footed booby colonies were also genetically differentiated within ocean basins, coalescent analyses indicated that populations have either diverged in the face of ongoing gene flow, or diverged without gene flow but recently made secondary contact. Regardless, gene flow among red-footed booby populations was higher than among brown booby populations. We suggest that these contrasting patterns of gene flow within ocean basins may be explained by the different habitat preferences of brown and red-footed boobies. © 2009 Elsevier Inc. All rights reserved.

Gomez C.,SELVA Investigacion Para la Conservacion en El Neotropico | Bayly N.J.,SELVA Investigacion Para la Conservacion en El Neotropico | Gonzalez A.M.,University of Saskatchewan | Abril E.,Jorge Tadeo Lozano University, Bogota | And 9 more authors.
Ornitologia Colombiana | Year: 2011

Research on Nearctic-Neotropical migratory birds in Colombia has strengthened in the last decade although most work has been centered on boreal migrants. Achievements are reflected in recent publications, in the studies presented at national ornithology conferences, and in the publication of the National Plan for Conservation of Migratory Species. However, there are still significant information gaps and challenges that must be addressed to guide the conservation of migratory bird populations in decline. During the III Colombian Ornithological Congress in 2010, twelve talks were presented during a symposium on migratory birds. The differentiation of studies between winter and migration periods stood out as a novelty, as well as the presentation of projects aimed at answering questions about the ecology of species instead of showing exclusively descriptive data. Discussions during the symposium generated new research questions and identified current gaps in knowledge. The main conclusion was that there is a need to generate information about the less studied migratory systems like the Neotropical austral, intratropical and local systems. For all systems we need a more comprehensive assessment of species' distribution ranges during stationary periods (or winter) and migration. Habitat use and relative habitat quality for different species, considering body condition and survival between periods, must be investigated as well. Studies on migratory strategies, migratory routes, survival during winter and migration, and on migratory connectivity, should be replicated in more species and locations because they are critical to understanding the mechanisms regulating populations and the conservation needs of each species. Finally, coordinated efforts, the publishing of research findings and the establishment of national and international alliances will be crucial to increase our knowledge on Nearctic-Neotropical-Austral migrants in Colombia.

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