http://hdl.handle.net/11606/456 Artículos que son de acceso abierto y están disponibles para bajar libremente 2026-04-16T10:32:50Z http://hdl.handle.net/11606/1553 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 http://hdl.handle.net/11606/1435 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