Estas colecciones contienen artículos científicos sobre Costa Rica, pero no necesariamente de investigaciones hechas en ACG http://hdl.handle.net/11606/455 2026-04-15T17:43:52Z 2026-04-15T17:43:52Z Monge Velázquez, Michelle Langen, Tom Sáenz, Joel http://hdl.handle.net/11606/1553 2022-10-31T17:33:55Z 2022-04-30T00:00:00Z

Seasonal High Road Mortality of Incilius luetkenii (Anura: Bufonidae) Along the Pan-American Highway Crossing the Guanacaste Conservation Area, Costa Rica Monge Velázquez, Michelle; Langen, Tom; Sáenz, Joel The Pan-American Highway in Costa Rica is currently undergoing expansion in capacity as a response to growth in vehicle traffic associated with growing international trade. This highway bisects the Pacific lowlands Tropical Dry Forest of the Guanacaste Conservation Area, a World Heritage site of the United Nations Educational, Scientific and Cultural Organization, with notably high biodiversity, including herpetofauna. As wildlifevehicle collisions are one of the main direct causes of animal mortality, we quantified the species composition, seasonality, and location of amphibians and reptiles killed along a 30 km segment of the highway running through the conservation area. From August 2016 to February 2017, we mapped roadkill hotspots using Kernel Density Estimation (KDE) with KDE+ software. We detected 1,298 carcasses of 28 species, including seven anuran, one caecilian, three lizard, 15 snake, and two turtle species; the Neotropical Yellow Toad (Incilius luetkenii) comprised over half the total roadkill. The two most severe roadkill hotspots were short road segments near seasonally flooded depressional wetlands where I. luetkenii and other anurans breed. We urge construction of mitigation measures including barriers and subterranean passages to conserve amphibian populations, especially if the Pan-American Highway will be widened at these sites.

2022-04-30T00:00:00Z Hilje, Branko Sánchez, Natalie V. Bayne, Erin M. Sánchez-Azofeifa, Arturo http://hdl.handle.net/11606/1435 2020-11-10T21:40:16Z 2020-05-26T00:00:00Z

Bird Assemblage Recovery in a Chronosequence of Tropical Dry Forests in Costa Rica Hilje, Branko; Sánchez, Natalie V.; Bayne, Erin M.; Sánchez-Azofeifa, Arturo Research Highlights: While forest structure recovery in successional tropical forests is well studied, the recovery of fauna and changes in species composition and assemblage along forests succession is not well understood in many areas of the Neotropics like tropical dry forests (TDFs). Background and Objectives: To compare bird species richness and assemblage in tropical dry forests (TDFs) of different ages of recovery from cattle ranching and relate both to forest structural characteristics. Materials and Methods: To sample bird species richness and assemblage in 16 successional forest of different ages (i.e., 20, 30, 40, and 60 years old) using autonomous sound recording units in the TDFs in Costa Rica. Results: A total of 64 species of birds was detected across all forest age classes. The highest species richness was found in the 20-year-old class. Species richness decreased as canopy openness increased, suggesting low forest structural complexity and low availability of perches, nesting sites and food sources. However, bird assemblages were similar among the different forest age classes, suggesting that age itself was not a strong predictor, likely because of high variation in structure within age classes. Conclusions: TDFs can recover structural characteristics important to birds in only a few decades, supporting a rapid bird species assemblage recovery. However, this seems to depend on the starting conditions of the site prior to being recovered. Young TDFs, 20 years old, provide similar habitats for birds as 60-year-old forests do. These findings provide relevant information on the influence of TDF recovery after severe human impact on a highly threatened ecosystem.

2020-05-26T00:00:00Z Basurto, Xavier http://hdl.handle.net/11606/491 2018-04-10T19:52:28Z 2013-01-01T00:00:00Z

Bureaucratic Barriers Limit Local Participatory Governance in Protected Areas in Costa Rica Basurto, Xavier The importance of local participation in biodiversity governance was recently recognised by the International Union for Conservation of Nature (IUCN) through the incorporation of Indigenous Peoples' and Local Community Conserved Territories and Areas (ICCAs) as a protected area category. This paper explores what barriers ICCAs might face in their successful implementation within already existing protected area systems. I look at this issue in the context of the decentralisation of biodiversity governance in Costa Rica and examine the internal makeup of four different conservation areas within the National System of Conservation Areas. My findings suggest that it is not enough to enact legal reforms allowing and encouraging local participation. Successfully involving local participation requires attention to the class-based relationships within the protected area bureaucracy that create incentives (or not) to link with the local rural citizenry affected by these areas. In three out of four conservation areas, the dominant social class and urban-rural dynamics combined with a lack of accountability mechanisms have discouraged any real rural involvement and empowerment for decision-making. The strategy of the one area that succeeded at sorting these obstacles to incorporate local participation is described in detail.

2013-01-01T00:00:00Z Werden, Leland K. Alvarado-J., Pedro Zarges, Sebastian Calderón-M., Erick Schilling, Erik M. Gutiérrez-L., Milena Powers, Jennifer S. http://hdl.handle.net/11606/458 2018-02-28T16:36:59Z 2017-04-04T00:00:00Z

Using soil amendments and plant functional traits to select native tropical dry forest species for the restoration of degraded Vertisols Werden, Leland K.; Alvarado-J., Pedro; Zarges, Sebastian; Calderón-M., Erick; Schilling, Erik M.; Gutiérrez-L., Milena; Powers, Jennifer S. 1. Tropical dry forests (TDFs) are critically endangered, and their restoration is understudied. Large-scale passive restoration efforts in north-west (NW) Costa Rica have catalysed TDF regeneration but are not effective on degraded Vertisols, where active restoration is necessary due to high content of shrink–swell clays that impede regeneration following degradation. 2. We established a large-scale restoration experiment in degraded former pastures in NW Costa Rica to determine (1) the restoration potential of native TDF tree species on Vertisols, (2) if plant functional traits elucidate mechanisms behind interspecific variability in species performance and (3) if affordable and readily available soil amendments increase seedling survivorship and growth. We planted 1,710 seedlings of 32 native species coupled with five amendments aimed at ameliorating root-zone microclimatic conditions: sand, rice hulls, rice hull ash, hydrogel and unamended controls. For each species, we quantified a suite of resource-acquisition and ecophysiological functional traits, and monitored survival and growth seasonally over 2 years. 3. Interspecific survivorship after 2 years ranged widely (0%–92.5%). Functional traits including wood density, photosynthetic parameters and upregulation of integrated water-use efficiency, explained interspecific variation in survivorship and growth at distinct ontogenetic stages. Easily measured leaf traits, however, were not good predictors of restoration potential. 4. Hydrogel and sand amendments increased initial seedling survival, but after 2 years no differences among treatments were found. 5. Synthesis and applications. We have shown it is possible, albeit challenging, to restore tropical dry forest (TDF) on degraded Vertisols. Our results support the use of functional trait-based screenings to select tree species for restoration projects as tree species with high survivorship and growth in this stressful environment have overlapping ecophysiological functional traits. Furthermore, practitioners should consider water-use and phytosynthetic traits when designing initial species mixes for TDF restorations.

2017-04-04T00:00:00Z