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Research about Columbia

Source-linked reports with geographic coverage including Columbia.

7 recordsLinked to original sources
USGS2023

Two new species of small-eared shrews of the Genus Cryptotis Pomel, 1848, from the Colombian Andes (Mammalia: Eulipotyphla: Soricidae)

Shrews (Mammalia: Eulipotyphla: Soricidae) reach the southern limit of their New World distribution in the Andes and eastern coastal highlands of northern South America. South of Honduras, the family is represented only by species of the genus Cryptotis Pomel, 1848. In South America, soricids are restricted to moist, high-elevation environments above 1000 m, and their distribution appears to be discontinuous. Study of specimens from a previous gap in the known geographical range of shrews in the Central Cordillera of southwestern Colombia reveals the presence of two unique populations that are distinguishable from each other and their congeners by a combination of morphological and morphometrical characters. They are described herein as, Cryptotis huttereri, n. sp. and Cryptotis andinus, n. sp. Both species are members of the Cryptotis thomasi group, one of five species groups of small-eared shrews defined partly on the basis of postcranial morphology and potential locomotor behavior. Although species in the C. thomasi group share similar postcranial architecture, as exemplified by the morphology of the forelimb, the group appears to be polyphyletic, implying convergence in locomotor behavior, possibly one uniquely adapted for Andean-type montane habitats. Recognition of C. huttereri and C. andinus brings the total number of known South American soricids to 19 species, with 11 species occurring in Colombia. Of those, seven species are endemic to that country.

Annals of the Carnegie Museum↗
USGS2022

The new lava dome growth of Nevado del Ruiz (2015–2021)

The morphology of the summit of Nevado del Ruiz volcano (Colombia) and its active Arenas crater is the product of complex interactions between effusive and explosive eruptions, and the dynamics of the summit glacier. Here, we document the morphologic evolution of the summit of Nevado del Ruiz, and the growth of its dome, from a variety of methods: monitoring data (2010 to 2021), photogrammetry, remote sensing, and quantitative modeling. The present morphology of Arenas crater, with small terraces limited by the walls of the crater, various vents of ash emission, and zones of fumarolic activity, has been shaped by the activity following the eruptions of 1845, 1985, 1989, 2012 and the volcanic unrest of the last 10 years. The latest emplacement of a lava dome at the bottom of the main crater began in 2015. The dome grew, with fluctuations in its extrusion rate between ~0.19 m 3 /s (November 2015) and 0.02 m 3 /s (February 2018), until December 2019, reaching a diameter of ~130 m, a maximum height of ~60 m, and a volume of 1.7 ± 0.2 × 10 6 m 3 .

Nevado del Ruiz volcano↗
USGS2012

Characterization of West Nile viruses isolated form captive American flamingoes ( Phoenicopterus ruber ) in Medellin, Colombia.

Serum samples from a total of 71 healthy captive birds belonging to 18 species were collected in July of 2008 in Medellin (Colombia) and tested for flaviviruses. Eighteen of 29 samples from American Flamingoes (Phoenicopterus ruber) were positive for West Nile virus (WNV) by reverse transcription-polymerase chain reaction. Selected positive samples were serially passaged and WNV was confirmed by immunofluorescence. Two isolates (524/08, 9835/08) were characterized in vitro and in vivo. Sequence analysis revealed WNV with 16 nucleotide substitutions resulting in six amino acid changes when compared with the NY99 strain. Colombian (COL) viruses were more closely related to Louisiana isolates from 2001. When compared with attenuated strains isolated from Texas, COL isolates differed in their plaque size and temperature sensitivity phenotype. The COL viruses were pathogenic in embryonated chicken eggs and Balb/c mice.

Medellin↗
USGS2009

The reintroduction of the Andean condor into Colombia, South America: 1989-1991

From 1989 to 1991,22 captive-reared Andean condors Vultur gryphus were released into three protected areas in the Andes of Colombia, South America. The goals of this reintroduction programme were to re-establish populations of these birds in protected habitat where the species had been extirpated, and to train local biologists in the conservation techniques necessary to recover their native condor. All birds were hatched, reared and released according to the protocols established by the US Fish and Wildlife Service and the California Department of Fish and Game for the California condor Gymnogyps californianus. At the time of release, the birds ranged in age from 11 to 26 months. Each bird was fitted with individually numbered wing tags and wing-mounted radio transmitters. Of the 22 released animals, 19 currently survive – a substantial increase to the wild population in Colombia, which had been estimated by Colombian biologists to number only 20 individuals.

Oryx↗
USGS1967

Phosphate rock in Colombia - a preliminary report, with a section on the phosphate occurrence at Turmeque

Exploration for phosphate rock in Colombia was successfully carried out in 3 1/2 months by the U.S. Geological Survey and the Inventorio Minero of the Servicio Geologico Nacional, under the auspices of the U.S. Agency for International Development. A modern theory of exploration based on model studies of phosphorite deposits is that phosphate is deposited in the miogeosyncline adjacent to the foreland or craton, where parts of the ocean are deep, where deposition of clastic material is at a minimum, and where upwelling currents deposit a suite of rocks characterized by chert, black shale, carbonate rock, and phosphorite. Although phosphate is found in rocks of all geologic periods, economic deposits are known only in certain of: the periods--one of these being the Late Cretaceous. As previous work had demonstrated that phosphate is present in Colombia only in rocks of Cretaceous age, and is most abundant in rocks of Late Cretaceous age--the La Luna Formations and Guadalupe--in the Cordillera Oriental, work was accordingly confined to the Cordillera Oriental and to rocks of Late Cretaceous age. Particular emphasis was paid to facies changes in the miogeosyncline; the field investigation pointed to the area in Norte de Santander where the best phosphorite was found. Phosphate deposits were found in both the geosynclinal and the platform facies in Upper Cretaceous rocks spread through a large area of the Cordillera Oriental, from Huila in the south to Norte de Santander in the north, a distance of more than 600 kilometers.

Open-File Report↗