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1.
PLoS One ; 19(3): e0300375, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38517860

RESUMEN

The jaguar (Panthera onca) is a charismatic species considered Vulnerable in Colombia but yet largely unknown in the country. The species is mostly threatened by the continuous decline in its habitats, mostly derived from deforestation and habitat loss, additional to hunting and conflicts with humans. Thus, the future of jaguars in Colombia depends on protecting and recovering existing habitats. The aims of this study were to 1) evaluate jaguar distribution and identify the remnant patches of habitat in Colombia, 2) define an ecological connectivity network within the country, and 3) propose a priority areas portfolio for the conservation and recovery of jaguars. We used a presence background model for estimating species potential distribution and subsequently identified remaining habitat patches across the country based on land cover and species-specific ecological attributes. We then created an ecological connectivity network based on circuit theory and following a multi-criteria approach identified jaguar priority areas for conservation (JPCA) and recovery (JPRA). Jaguar potential distribution comprises 1103122.43 km2, from which 56.71% maintain suitable patches of potential habitat. We identified 960 corridors between remnant patches of natural or semi-natural vegetation. Based on the criteria, JPCAs with greater importance were identified in each of the five Colombian regions. JPRAs were located mainly towards the Andean and Caribbean regions. These JPCAs and JPRAs could serve as a guide for designing and implementing management strategies for the long-term conservation and recovery of the species in Colombia.


Asunto(s)
Panthera , Animales , Humanos , Colombia , Conservación de los Recursos Naturales , Ecosistema , Región del Caribe
2.
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
3.
PLoS One ; 17(8): e0267589, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35930545

RESUMEN

Conservation biogeography, which applies principles, theories, and analyses of biodiversity distribution patterns to address conservation challenges, can provide valuable insight and guidance to policy making for protection of biodiversity at multiple scales. The temperate and tropical ecosystems of the Nearctic-Neotropical transition in the small western state of Colima, Mexico, support a mosaic of remarkably diverse fauna and flora and provide a rare opportunity to determine spatial distribution patterns of terrestrial vertebrate species, assess human-induced threats, and identify potential conservation strategies. We analyzed the spatial distribution patterns and correlated them with the current land cover and extent of the protected areas. Despite its limited geographic extension, 29% (866) of all vertebrates, and almost a quarter of both endemic and threatened species in Mexico, live in Colima. Our analysis identified clear high-richness concentration sites (i.e., "hotspots") coincident for all groups and that elevation and both temperate and tropical ecosystems composition exert significant influence on richness patterns. Furthermore, current species´ distribution also showed significant correlation with natural and disturbed landcover. Significant hotspots for all species groups coincided poorly with the limited protected areas in the state (only 3.8%). The current state of natural land cover (less than 16%) in the state, coupled with its remarkable biological importance, highlights the need for further complementary conservation efforts including expansion and creation of new protected areas, significant restoration efforts and other conservation measures to maintain this uniquely biogeographic and biological diverse region of the country.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Animales , Biodiversidad , Humanos , México , Vertebrados
4.
R Soc Open Sci ; 9(1): 201154, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35242340

RESUMEN

Protected areas (PAs) constitute one of the main tools for global landscape conservation. Recently, payments for environmental services (PES) have attracted interest from national and regional governments and are becoming one of the leading conservation policy instruments in tropical countries. However, the degree to which areas designated for PES overlap with areas that are critical for maintaining species' landscape connectivity is rarely evaluated. We estimated habitat distributions and connectivity for 16 of the 22 mammalian carnivores occurring in the Caribbean region of Colombia, and identified the overlap between existing PAs and areas identified as being important for connectivity for these species. We also evaluated the potential impact of creation of new PAs versus new PES areas on conserving connectivity for carnivores. Our results show that PAs cover only a minor percentage of the total area that is important for maintaining connectivity ( x = 26.8 % ± 20.2 s . d . ). On the other hand, PES, if implemented extensively, could contribute substantially to mammalian carnivores' connectivity ( x = 45.4 % ± 12.8 s . d . ). However, in a more realistic scenario with limited conservation investment in which fewer areas are set aside, a strategy based on implementing new PAs seems superior to PES. We argue that prioritizing designation of new PAs will be the most efficient means through which to maintain connectivity.

5.
PLoS One ; 16(10): e0255555, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34613994

RESUMEN

The jaguar (Panthera onca) is one of the most threatened carnivores in the Americas. Despite a long history of research on this charismatic species, to date there have been few systematic efforts to assess its population size and status in most countries across its distribution range. We present here the results of the two National Jaguar Surveys for Mexico, the first national censuses in any country within the species distribution. We estimated jaguar densities from field data collected at 13 localities in 2008-2010 (2010 hereafter) and 11 localities in 2016-2018 (2018 hereafter). We used the 2010 census results as the basis to develop a National Jaguar Conservation Strategy that identified critical issues for jaguar conservation in Mexico. We worked with the Mexican government to implement the conservation strategy and then evaluated its effectivity. To compare the 2010 and 2018 results, we estimated the amount of jaguar-suitable habitat in the entire country based on an ecological niche model for both periods. Suitable jaguar habitat covered ~267,063 km2 (13.9% of the country's territory) in 2010 and ~ 288,890 km2 (~14.8% of the country's territory) in 2018. Using the most conservative density values for each priority region, we estimated jaguar densities for both the high and low suitable habitats. The total jaguar population was estimated in ~4,000 individuals for 2010 census and ~4,800 for the 2018 census. The Yucatan Peninsula was the region with the largest population, around 2000 jaguars, in both censuses. Our promising results indicate that the actions we proposed in the National Jaguar Conservation Strategy, some of which have been implemented working together with the Federal Government, other NGO's, and land owners, are improving jaguar conservation in Mexico. The continuation of surveys and monitoring programs of the jaguar populations in Mexico will provide accurate information to design and implement effective, science-based conservation measures to try to ensure that robust jaguar populations remain a permanent fixture of Mexico's natural heritage.


Asunto(s)
Conservación de los Recursos Naturales/legislación & jurisprudencia , Panthera/fisiología , Política Pública/legislación & jurisprudencia , Animales , Ecosistema , México , Densidad de Población
6.
Integr Zool ; 15(6): 471-481, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32427390

RESUMEN

During the last century, the coyote (Canis latrans) has increased its distribution in Central America. Before the 1980s, it had not been recorded in Panama. New records show that coyotes have crossed the Panama Canal, indicating that continues to expand; therefore, there is a possibility that it will reach northern South America. Our objectives were to identify potential coyote colonization routes to South America, and the variables that favor its expansion. We hypothesized that habitat fragmentation benefits coyote expansion. We applied 7 algorithms to model the potential distribution of the coyote, using 196 presence records and 12 variables. The models with better performance were used to generate a consensus model. Using our consensus model and the areas with highest probability of presence, a potential colonization route was generated between Central America and northern South America. This route lies through southern Costa Rica, along the Pacific coast of Panama to the south, to the Andean mountains in northern Colombia. The variables that explained potential coyote distribution were human population density, altitude, and percentage of crops with positive influence, and tropical broadleaf forests with negative influence. These results indicate that human activities and deforestation are related to coyote distribution expansion. Actions can be implemented within the identified route to improve environmental management, in order to avoid the presence of the coyote in the ecosystems of northern South America.


Asunto(s)
Distribución Animal , Coyotes , Especies Introducidas , Algoritmos , Altitud , Animales , América Central , Ecosistema , Fenómenos de Retorno al Lugar Habitual , Humanos , Densidad de Población , América del Sur
7.
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.

8.
Acta biol. colomb ; 22(2): 242-245, mayo-ago. 2017. ilus, tab
Artículo en Español | LILACS | ID: biblio-886063

RESUMEN

RESUMEN Presentamos un nuevo reporte de la tortuga escorpión Kinosternon scorpioides scorpioides para el departamento de Norte de Santander, Colombia. Este espécimen fue colectado en el bosque seco tropical del departamento, el cual es uno de los ecosistemas más amenazados y menos protegidos del país; esto agravado por problemas locales de contaminación y de transformación del uso del suelo, motivos por los que la presencia y conservación de K. s. scorpioides se encuentra en riesgo.


ABSTRACT We present a new record of the Scorpion Turtle Kinosternon scorpioides scorpioides for the department of Norte de Santander, Colombia. This specimen was collected in the tropical dry forest of the department, which is one of the most threatened and least protected ecosystems in the country; this exacerbated by local problems related with pollution and land-use transformation, threatening the presence and conservation of K. s. scorpioides.

9.
PLoS One ; 12(4): e0175931, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28441467

RESUMEN

Functional diversity represents a measure of diversity that incorporates the role of species in an ecosystem, and therefore its dynamics and resilience. Assessing its drivers and spatial variation represents an important step forward in our understanding of functional ecosystem dynamics and it is also necessary to achieve a comprehensive conservation planning. In this paper, we assessed mammal functional diversity for the 218 ecoregions within the Neotropical realm. We evaluated the overall influence and spatial variation of species richness, ecoregion extent, intervention and species at risk on functional diversity. Using ordinary least squares and geographically weighted regression modeling approaches, we found that intervened areas and threatened and non-threatened species are the most influential overall drivers of functional diversity. However, we also detected that these variables do not operate equally across scales. Our local analyses indicated both that the variation explained and local coefficients vary spatially depending on the ecoregion and major habitat type. As estimates of functional diversity are based on current distribution of all mammals, negative influence of intervened areas and positive influence of non-threatened species may reflect a potential degradation of functional processes for some ecosystems. Most generally, the negative influence of intervention together with the influence of threatened species indicates that some areas are currently more susceptible to functional diversity loss. Our results help to pinpoint key areas requiring urgent conservation action to reduce natural land-cover loss and areas where threatened species play influential roles on ecosystem functioning.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Especies en Peligro de Extinción , Extinción Biológica , Mamíferos , Distribución Animal , Animales , Ecosistema , Mamíferos/fisiología , Recursos Naturales , América del Sur , Clima Tropical
10.
Zootaxa ; 4059(3): 541-54, 2015 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-26701577

RESUMEN

Caiman crocodilus apaporiensis has been considered by several authors as an extreme of morphological variation within the Caiman crocodilus complex. Here, we evaluate its position in the Caiman crocodilus complex morphospace using morphological traits from head shape. We examined the holotype and seventeen paratypes of Caiman crocodilus apaporiensis Medem 1955 deposited at the Field Museum of Natural History. We performed multivariate morphometric analyses: principal component analysis (PCA) and discriminant function analysis (DFA), based on 21 cranial traits of of C. c. apaporiensis, C. yacare and the C. crocodilus complex (C. c. chiapasius, C. c. fuscus andC. c. crocodilus). We find a notable separation of C.c. apaporiensis from C. yacare and C. crocodilus complex in the morphospace. We suggest that geographic isolation might have driven this morphological separation from the C. crocodilus complex, but further analysis are necessary to confirm whether these differences are related with genetic differentiation within the complex. In addition, we suggest that environmental heterogeneity might drive the evolution of independent lineages within the C. crocodilus complex.


Asunto(s)
Caimanes y Cocodrilos/clasificación , Caimanes y Cocodrilos/anatomía & histología , Caimanes y Cocodrilos/crecimiento & desarrollo , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Femenino , Masculino , Tamaño de los Órganos
11.
PLoS One ; 10(5): e0124480, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25970293

RESUMEN

Costa Rica has one of the greatest percentages (26%) of protected land in the world. The National Protected Areas System (NPAS) of Costa Rica was established in 1976 and currently includes >190 protected areas within seven different protection categories. The effectiveness of the NPAS to represent species, populations, and areas with high species richness has not been properly evaluated. Such evaluations are fundamental to understand what is necessary to strengthen the NPAS and better protect biodiversity. We present a novel assessment of NPAS effectiveness in protecting mammal species. We compiled the geographical ranges of all terrestrial Costa Rican mammals then determined species lists for all protected areas and the estimated proportion of each species' geographic range protected. We also classified mammal species according to their conservation status using the IUCN Red List of Threatened Species. We found almost complete representation of mammal species (98.5%) in protected areas, but low relative coverage (28.3% on average) of their geographic ranges in Costa Rica and 25% of the species were classified as underprotected according to a priori representation targets. Interestingly, many species-rich areas are not protected, and at least 43% of cells covering the entire country are not included in protected areas. Though protected areas in Costa Rica represent species richness well, strategic planning for future protected areas to improve species complementarity and range protection is necessary. Our results can help to define sites where new protected areas can have a greater impact on mammal conservation, both in terms of species richness and range protection.


Asunto(s)
Distribución Animal/fisiología , Conservación de los Recursos Naturales/estadística & datos numéricos , Especies en Peligro de Extinción/estadística & datos numéricos , Mamíferos/fisiología , Animales , Biodiversidad , Conservación de los Recursos Naturales/legislación & jurisprudencia , Costa Rica , Especies en Peligro de Extinción/legislación & jurisprudencia , Humanos , Filogeografía , Dinámica Poblacional
12.
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
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