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Por: Dora Nancy Padilla-Gil | Fecha: 2017

New records of sixteen species of water bugs are reported, belonging to 10 genera and seven families. Expansions of the geographical distribution are presented for 12 species and three species are recorded for the first time from Colombia: Ovatametra fusca Kenaga, 1942; Ovatametra gualeguay Bachmann, 1966 and Pseudosaldula saxicola Schuh and Polhemus, 2009, a diagnose and illustrations are included for each one of these species. Maps show the geographical distribution of all species.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros

Por: Wolfgang Buitrago | Fecha: 2016

Se presentan los resultados de una caracterización rápida de los anuros presentes en ocho localidades de los complejos paramunos de Los Nevados, Chilí-Barragán y Las Hermosas, ubicados en los departamentos de Quindío, Valle del Cauca y Tolima, cordillera Central de Colombia. Registramos 263 individuos pertenecientes a 11 especies de anuros de las familias Craugastoridae y Bufonidae. La riqueza local fue pobre (3-5 especies) pero la mayoría de especies (8 de 11) son endémicas para Colombia y al menos dos (Osornophryne percrassa y Pristimantis simoteriscus) están catalogadas con algún riesgo de amenaza. La mayoría de especies son de actividad nocturna-arbórea y reproducción terrestre; se amplía el rango de distribución conocido para tres especies (Pristimantis simoterus, Pristimantis obmutescens, Pristimantis vicarius). Además, presentamos un compendio actualizado de los anuros registrados en el ecosistema de páramo de Colombia. Nuestros registros contribuyen con información básica sobre la presencia actual de especies en estos ecosistemas y aportan a una línea base para el establecimiento de eventuales planes de monitoreo.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros

Por: Germán Camargo Ponce de León | Fecha: 2017

Along the vertical gradients from the Xeridas plateau to the canyons of the lower Chicamocha and the upper Sogamoso rivers, three landscapes are identified: high plateau, hanging valleys and canyon, corresponding to socio-ecosystemic scenarios. Physical environment, vegetation and degree of alteration of the systems that conform these landscapes are described. The history of disturbance from prehispanic to present times and the resulting patterns of ecological change point to a sequence of different means of transformation that overlap historically in this system, and that can be interpreted as a stratified landscape with a trend of degradation that continues today. The restoration model is constructed at three scales, macro, mid and micro: landscape, micro-drainages, and individual properties. The objective is to introduce at each scale a regenerative trajectory aiming to restore a dynamic equilibrium between the components of conservation, regeneration, production and shelter articulated along vertical corridors of the canyons and oriented by fair water use and conservation by highlands and lowlands.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros

Por: Claudia A. Medina-Uribe | Fecha: 2016

The species list of dung beetles of the dry forest of Colombia from the Entomological Collection of the Alexander von Humboldt Institute is presented. A total of 19.797 specimens of 68 species, the largest number of species registered for different localities in dry forest in Colombia, were reviewed. The taxonomic problems within the subfamily Scarabaeinae in Colombia are discussed; and a unique code for each morpho-species is proposed to further the the standardization of identification for records that cannot be identified to species. Only 35 species (51 %) could be identified to species, the others were codified.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros

Por: Luz A. Pulido-Herrera | Fecha: 2016

Potential areas of distribution of the common cattle tick Rhipicephalus (Boophilus) microplus in the Altiplano Cundiboyacense are presented, using two algorithms of ecological niche modeling (Maxent and Classification Trees). The algorithms were complementary, with excellent and significant returns, registering AUC (0.70 and 0.90 Maxent Classification Trees), and low values of omission errors (0.00% and 4.6% Maxent Classification Trees). The landscape along with the presence of the host, altitude, precipitation, temperature and humidity of the first wet quarter, were the most important variables in modeling. The north-eastern region of the Altiplano has the best potential for the establishment of this species.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros

Por: Juan David Amaya-Espinel | Fecha: 2017

The quantification and classification of the risk of extinction for a species within a country or region and the publication of red list are fundamental tools for preventing and managing the loss of biodiversity on a sub-global scale of anthropogenic activity. Colombia may be considered a regional leader in the development of this type of risk analysis (i.e. red books published in 2002 and recent re evaluations of birds and freshwater fish); however, there are many challenges to increasing taxonomic coverage, periodic assessments, sustainability and also the influence on conservation planning and management in Colombia. This working paper presents a proposal to create, implement and consolidate an -Operative System for Risk Extinction Analysis and Monitoring of the Colombian Wildlife to address more effectively the challenges outlined above. It originates from research that identified progress and gaps on this issue in Colombia in relation to other countries of the world and also from discussions and recommendations by South America fauna experts. Based on these elements, the proposal presents objectives, guidelines, instances, roles, activities and work schemes that should be considered relevant to increase the rigor, transparency, periodicity, sustainability and impact of the wildlife risk assessments in Colombia. The system here presented is preliminary and should be amply consulted and discussed in order to make the necessary adjustments to obtain a definite working model for Colombia.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros

Por: Catalina Gutiérrez-Chacón | Fecha: 2016

The dry enclave of Amaime River is one of the few places that remain as Tropical Dry Forest in the Valle del Cauca department, which is considered one of the most threatened ecosystems in the Neotropics. The site has been heavily transformed and threatened by anthropic means like continued burning for the suitability of land for agriculture and livestock, small short rotation crops among others. The aim of the study was to develop detailed inventories of avifauna, herpetofauna, mammalian fauna, and flora in relict sub-xerophytic forests of the enclave, therefore revealing the biodiversity of these remnants, their conservation status and potential threats in order to propose recommendations for conservation. Four sampling areas were selected with cover vegetation as thorny scrub vegetation, riparian forests and forest fragments. For registration and data collection mist nets, transects, direct observations and Sherman traps were used, additionally informal interviews with the community were performed. Despite the reduction of vegetation cover in the dry enclave of Amaime River, the forest fragments serve as shelter and feeding site for both transient species and typical dry and very dry forest wildlife.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Vegetación
Otros
Zoología
Aves

Por: Hipólito Alvarado-Álvarez | Fecha: 2016

A total of 6634 vascular plant specimens deposited in the UCOB Herbarium from Lara state until 2014 were reviewed in order to improve our knowledge about the flora. The most prominent collectors are Robert Smith, Hipólito Alvarado, Bolivia Mediomundo, Charles Burandt Jr., José Antonio Casadiego and Alcides Mondragón. 1659 species were recorded in 859 genera and 155 botanical families, accounting for 64.7% of the families, 36.5% of the genera and 11.3% of the Angiosperm species occurring in the country. Families with higher numbers of species were: Leguminosae (181), Poaceae (166), Asteraceae (125), Rubiaceae (95), Euphorbiaceae (65)and Malvaceae (54). Genera with higher numbers of species were: Paspalum (22), Miconia (20), Cyperus (19), Solanum (18), Piper (16), Senna (15) and Tillandsia (14). Of the total species, 308 are new records and four are endemic to Lara state. The most explored regions are: Serranía de Portuguesa, Serranía de Barbacoas, Serranía de Bobare and gallery forest of the Tocuyo River Basin. The most explored county was Morán (26.7 %), followed by Palavecino (18.8 %) and Iribarren (15,6 %), the least explored were Jiménez (3.7 %) and Torres (4.9 %) municipalities.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros

Por: Jonathan Álvarez | Fecha: 2016

The Magdalena-Cauca River basin has 213 species of freshwater fish, of which slightly more than 50% are endemic. This basin accounts for 80% of the Colombian population, holds 80% of the national GDP and within its channels are located the 84% of the hydroelectric plants that supply energy to Colombia. The Andean mountains generate altitudinal gradients in aquatic systems as well as its associated biota along the Magdalena-Cauca basin. To analyze the interaction between the altitudinal gradient in the distribution of species of freshwater fish and the location of existing reservoirs, it was performed an analysis of the altitudinal distribution of endemic and migratory fish species and their implications for their conservation based on the current and future state in the formation of reservoirs, using a review of case studies at global and national levels. It was found that the number of species is inversely proportional to altitude, while the endemics are directly proportional and reservoirs below 700 m altitude affect the conservation status of migratory species. A reservoir creates new species richness gradients and modifies the channels that are used by migratory species as spawning areas. We conclude that the development of the hydropower based on the use of water in the Andean rivers and another activities associated with economic development of Colombian society, has led to changes in freshwater aquatic systems in the Magdalena-Cauca basin, influences in the structure of the assemblages of species of fish and in the dynamic of migration and spawning of freshwater fish species important for artisanal fisheries.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros

Por: Magnolia Longo | Fecha: 2016

Para el establecimiento y el desarrollo de los macroinvertebrados en los sistemas leníticos es importante que los sustratos disponibles sean variados. Así, la biomas de los taxones es un reflejo de la producción del sistema. Este estudio evaluó la diversidad en cuatro sustratos: macrófita (Myriophyllum aquaticum), roca, sedimentos y materia orgánica, y se analizó la variación temporal de la biomasa y la abundancia con base en tres períodos hidrológicos. Se colectaron 2.957 individuos (17 géneros, 11 órdenes). Helobdella fue el taxón dominante aportando 90 % a la biomasa total de la comunidad, seguido de Hyalella, Tanytarsus y Centrocorisa. La conductividad, los sulfatos y la temperatura hídrica fueron determinantes para la biomasa. En la macrófita se encontró menor diversidad de H’ (0,03 nats.ind-1) y mayor dominancia (0,99); en el resto de sustratos la diversidad fue mayor (X = 1,5) y la dominancia menor (X = 0,24). Se encontraron diferencias significativas en los registros de biomasa entre sustratos más no entre campañas. En conclusión, el sustrato macrófita es el hábitat más utilizado por los macroinvertebrados pues alberga mayor cantidad de individuos; sin embargo, no presenta la mayor diversidad, a diferencia de los otros tres sustratos que evidencian mayor diversidad de taxones.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros