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1.
PLoS One ; 17(9): e0273750, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36099258

RESUMEN

Leopardus tigrinus is among the least known carnivore species in the Neotropics, including considerable taxonomic uncertainty. Here we model the distribution, connectivity and overlap with existing conservation areas for the species in Colombia. Using a Species Distribution Modeling approach, we estimated current potential range of the species in Colombia and identified potential habitat blocks remaining in the country. In addition, we designed a connectivity network across the available cores, using a circuit theory approach, to evaluate habitat linkage. Finally, we defined a prioritization scheme for the remaining habitat cores and assessed the level of coverage of protected areas for the country. L. tigrinus is potentially present across the three Andean branches of Colombia, with still considerable continuous habitat cores, mostly located on the eastern and central Andean ranges. Most habitat cores are theoretically connected, but nearly 15% are isolated. Priority areas were located across the eastern and central ranges, but with very significant and promising cores in the northern eastern and western ranges. Current level of protection indicates nearly 30% of the range is "protected", but only about 25% is under national strict protected areas. Evolution of this coverage showed some periods of significant increase but interestingly the number of cores grew at a faster rate than overall proportion protected, likely indicating numerous discontinuous fragments, and not contiguous functional landscapes. This represents the most updated assessment of the distribution and conservation status for the species in Colombia, and indicates the numerous conservation opportunities, especially in most populated areas of the country. We found unique business environmental passive's opportunities, including compensation and development potential, which are becoming more available in the country.


Asunto(s)
Carnívoros , Tigres , Animales , Colombia , Conservación de los Recursos Naturales , Ecosistema
2.
PeerJ ; 8: e8414, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31998562

RESUMEN

We used data from eight years of camera trapping at Rancho El Aribabi, a cattle ranch and conservation property in northern Sonora, Mexico, to examine the ecology of the northern-most known breeding population of ocelots (Leopardus pardalis). Ocelots were found mostly in two discrete and disjunct areas: a riverine riparian canyon at just less than 1,000 masl elevation and along arroyos in an oak-mesquite savanna in the Sierra Azul at 1,266-1,406 masl. An ocelot was also detected at a site between those two areas, in an area of a Sonoran desertscrub-foothills thornscrub ecotone at 1,300 masl. At least 18 ocelots, both males and females, were detected during the 2007-2011 and 2014-2018 sampling periods. A female with a kitten was documented in 2011. No individual ocelots were photographed in both areas, which are separated by a minimum of 11.29 km, and no individuals were photographed in both time periods. In a binary logistic regression, key environmental variables predicting ocelot presence were, in order of importance, distance to a paved road, distance to human habitation, proximity to water, and an anthropogenic influences index that was dominated by cattle. Another analysis corroborated the finding regarding ocelot presence and cattle. Contrary to previous studies, ocelot presence was not tied to vegetation cover close to the ground. We present information about the types of habitats and sites ocelots used, short-term movements, daily and seasonal activity patterns, and behavior, including occurrence of different individuals at or near the same site over short periods of time. We discuss ocelot home range, density, and movements, but small sample sizes and study design problems limit the value of estimates derived from our work. Rancho El Aribabi is a private, conservation ranch for which the owners have made voluntary conservation commitments that provide habitat and protection for ocelots and other animals and plants. This northern-most known breeding population is a likely source of ocelots that are periodically detected in southeastern Arizona. Our results should help facilitate conservation of the ocelot in other semi-arid areas of northwestern Mexico and adjacent USA.

3.
Acta biol. colomb ; 24(2): 403-406, May-ago. 2019. graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1010869

RESUMEN

ABSTRACT Atelopus varius was believed to be extinct in Costa Rica until the rediscovery of a population within the Las Tablas Protected Zone (LTPZ) in 2008. This rediscovery represented a research and conservation opportunity, including contributing new information about the species' natural history. There are few reported species that prey on A. varius. This report presents a new predation record by a species of water bug (Abedus spp.) on an adult harlequin frog (A. varius). This is only the second confirmed predator for the species. These water bugs have been reported to prey on anurans during reproductive seasons, but in this case, the event occurred on A. varius out of their reproductive season. The effects of water bug predation on the only known reproductive population of this Critically Endangered species needs to be assessed to consider appropriate conservation measures to prevent further decline of the species.


RESUMEN Atelopus varius se consideró extinto en Costa Rica, hasta el redescubrimiento de una población en la Zona Protectora Las Tablas (ZPLT). Este hallazgo representa una oportunidad de investigación y conservación, incluyendo contribuir nueva información acerca de la historia natural de la especie. Hay pocas especies reportadas que depredan A. varius. Este reporte presenta un registro de depredación del chinche de agua (Abedus spp.), sobre un adulto de Sapo Arlequín (A. varius), como el segundo depredador confirmado de la especie. Usualmente, los chinches de agua depredan anuros durante su época reproductiva, pero este evento ocurrió fuera de la época reproductiva de A. varius. Los efectos de la depredación de chinches acuáticos sobre la única población reproductiva conocida de esta especie Críticamente Amenazada necesitan ser evaluados para considerar acciones de conservación.

4.
Integr Zool ; 7(4): 381-388, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23253369

RESUMEN

Baird's tapir (Tapirus bairdii) is currently endangered throughout its neotropical range with an expected population decline >50% in the next 30 years. We present the first density estimation of Baird's tapir for the Talamanca mountains of Costa Rica, and one of the first for the country. Ten stations with paired cameras were established in Valle del Silencio within Parque Internacional La Amistad (PILA). Seventy-seven tapir pictures of 15 individuals comprising 25 capture-recapture events were analyzed using mark-recapture techniques. The 100% minimum convex polygon of the sampled area was 5.7 km(2) and the effective sampled area using half mean maximum distances moved by tapirs was 7.16 km(2) . We estimated a tapir density of 2.93 individuals/km(2) which represents the highest density reported for this species. Intermountain valleys can represent unique and important habitats for large mammal species. However, the extent of isolation of this population, potentially constrained by steep slopes of the cordillera, remains unknown. Further genetic and movement studies are required to understand meta-population dynamics and connectivity between lowland and highland areas for Baird's tapir conservation in Costa Rica.


Asunto(s)
Ecosistema , Especies en Peligro de Extinción , Perisodáctilos/fisiología , Árboles , Animales , Costa Rica , Fotograbar , Densidad de Población
5.
Conserv Biol ; 23(6): 1418-26, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20078642

RESUMEN

Modern global temperature and land cover and projected future temperatures suggest that tropical forest species will be particularly sensitive to global warming. Given a moderate greenhouse gas emissions scenario, fully 75% of the tropical forests present in 2000 will experience mean annual temperatures in 2100 that are greater than the highest mean annual temperature that supports closed-canopy forest today. Temperature-sensitive species might extend their ranges to cool refuges, defined here as areas where temperatures projected for 2100 match 1960s temperatures in the modern range. Distances to such cool refuges are greatest for equatorial species and are particularly large for key tropical forest areas including the Amazon and Congo River Basins, West Africa, and the upper elevations of many tropical mountains. In sum, tropical species are likely to be particularly sensitive to global warming because they are adapted to limited geographic and seasonal variation in temperature, already lived at or near the highest temperatures on Earth before global warming began, and are often isolated from cool refuges. To illustrate these three points, we examined the distributions and habitat associations of all extant mammal species. The distance to the nearest cool refuge exceeded 1000 km for more than 20% of the tropical and less than 4% of the extratropical species with small ranges. The biological impact of global warming is likely to be as severe in the tropics as at temperate and boreal latitudes.


Asunto(s)
Calentamiento Global , Mamíferos/fisiología , Temperatura , Clima Tropical , Animales , Biodiversidad , Conservación de los Recursos Naturales , Extinción Biológica , Geografía , Fenómenos de Retorno al Lugar Habitual , Estaciones del Año
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