Anurans trophic dynamic and guild structure in tropical dry forests of the Caribbean region of Colombia

Studies on the exploitation of trophic resources allow to establish interactions between predators and predator-prey, and this dynamic can present fl uctuations over time and space. We analysed stomach contents of 19 anuran species from tropical dry forests of Colombia, quantifi ed the overlap between species and identifi ed anuran trophic guilds. Most of the species were generalists in diet (89.5%), some with strong prey dominance and only two species were classifi ed as specialists. Two anurans guilds were identifi ed according to diet structure and habitat use: “ground foraging anurans, consuming Formicidae and Isoptera” and “arboreal ‘sit-and-wait’ predators, primarily consuming arachnids”. A considerable number of species did not clearly group in community trophic structure analysis. The level of taxonomic resolution with that preys are worked affects analysis of trophic niches segregation when analyzing regional and local patterns. Anuran species of tropical dry forest in the Colombian Caribbean display trophic resources partitioning at the level of species and/or morphospecies, as a mechanism of coexistence

Habitat modification effects on anuran food webs in the Colombian tropical dry forest

Habitat loss and transformation are major threats to biodiversity and ecosystem functioning, but their effects on species interaction are often poorly understood. We evaluated effects of habitat transformation and seasonality on anuran-prey food webs in Colombian dry-forests. We asked whether anthropic transformation (anthropic vs natural) and/or seasonality (dry, minor and major rain seasons) affect predator load on arthropods, the occurrence of energetic bottlenecks, and the diet overlap of anurans. We selected six dry forest sites in the Caribbean of Colombia, sampled anurans, and identified their stomach contents to construct anuran-prey food webs. We show that the global structure of food webs was affected by disturbance and seasonality, but not by their interaction. Prey vulnerability was higher in anthropic habitats. Habitat transformation enhanced diet overlap among predators, but there was not a differential effect of habitat type according to seasonality for network metrics. Our study shows a strong effect of natural vegetation modification in tropical dry forest on anuran-prey food webs, while seasonality did not seem to further mediate these effects

Trophic Relationships among Five Species of Anura in the Colombian Caribbean Tropical Dry Forest: A Spatial and Temporal Approach

Species of Bufonidae and Leptodactylidae are common in the Colombian tropical dry forest. Although some of them are associated with active foraging and consumption of termites and ants, their trophic ecology is mostly unknown. The diet of five anuran species of Bufonidae (Rhinella horribilis, R. humboldti) and the leptodactylid subfamily Leiuperinae (Engystomops pustulosus, Pleurodema brachyops, and Pseudopaludicola pusilla) was examined at six sites of the Colombian Caribbean in fragments of dry forest and different land uses. A total of 310 food items were identified. The greatest contribution was represented by Coleoptera, Hymenoptera (Formicidae), Isoptera, and Diptera. The species differed in number and volume of prey. Except for Pseudopaludicola pusilla, which behaves as a generalist predator, species had high intake of termites and ants. Engystomops pustulosus preferred termites, Pleurodema brachyops had high consumption of ants and termites, and the two bufonid species were myrmecophagous. Except for Pseudopaludicola pusilla, predator and prey size was related. Most species have overlapping diets (spatially and temporally) when analyzing food items identified at the order level. However, the richness of different prey within these orders allows the coexistence of species. The diet of these species presents similar trends in different habitats throughout their distribution area

Observations about the diet of Elachistocleis pearsei and Elachistocleis panamensis in two disturbed areas of northern lowlands of Colombia

Se describe la dieta de 2 especies de Elachistocleis para tierras bajas del norte de Colombia. Debido a las características de su dieta (composición, volumen promedio, número de presas por estómago y registro en otros congéneres), E. pearsei y E. panamensis son forrajeros activos y especialistas en el consumo de termitas y hormigas.The diet of 2 species of Elachistocleis in the lowlands of Northern Colombia is described. Due to the characteristics of their diet (composition, volume, average number of prey per stomach, and the records of another related species) E. pearsei and E. panamensis are active foragers, and termite-and ant-eating specialists.Fil: Blanco Torres, Argelina. Universidad Nacional de Colombia; ColombiaFil: Duré Pitteri, Marta Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Bonilla, María Argenis. Universidad Nacional de Colombia; Colombi

Pithecopus hypochondrialis (Orange-legged Leaf Frog): Diet

Pithecopus hypochondrialis is an arboreal frog found in the foothills of the eastern Andean cordillera and savannas of the Orinoquia región in Colombia, through western and eastern Venezuela and parts of the Guianas, and in Brazilian Amazonia between 169–1125 m elev...Fil: Pachón Forero, Sara. Universidad de la Salle;Fil: Blanco Torres, Argelina. Universidad de la Costa.; ColombiaFil: Duré Pitteri, Marta Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentin

Interacción depredador-presa en anuros de bosque seco tropical del caribe colombiano

En este espacio propiciado por el Departamento de Ciencias Naturales y Exactas, se habla sobre la investigación realizada en el bosque seco tropical del caribe colombiano, donde se tomaron muestras de anfibios depredadores como lo son las ranas, sus rasgos morfológicos, locomoción, reproducción, ecología y cinemática. También se estudian las presas: insectos como arañas, escarabajos, hormigas, sus mecanismos de defensa, capacidad de escape, movilidad y ecologíaDepartamento de Ciencias Naturales y Exacta

Pithecopus hypochondrialis (Orange-legged Leaf Frog): Diet

Pithecopus hypochondrialis is an arboreal frog found in the foothills of the eastern Andean cordillera and savannas of the Orinoquia región in Colombia, through western and eastern Venezuela and parts of the Guianas, and in Brazilian Amazonia between 169–1125 m elev...Fil: Pachón Forero, Sara. Universidad de la Salle;Fil: Blanco Torres, Argelina. Universidad de la Costa.; ColombiaFil: Duré Pitteri, Marta Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentin

Phyllomedusa Venusta (Lovely Leaf Frog)

PHYLLOMEDUSA VENUSTA (Lovely Leaf Frog). DIET.Phyllomedusa venusta is an arboreal frog found in northern Colombia, the valley of Magdalena, the Darién on both sides of the ColombiaPanamá border, and western Venezuela. The species is common, but populations are decreasing due to deforestation by agricultural and livestock activities, illegal plantations, human establishments, and use of agrochemicals (Rodríguez-Mahecha et al. 2008. Guía Ilustrada de Fauna del Santuario de Vida Silvestre Los Besotes,Valledupar, Cesar, Colombia. Editorial Panamericana, Formas e Impresos, Bogotá, Colombia. 574 pp.). The food habits and many other aspects of its biology and ecology are unknown. Herein we describe the diet of P. venusta in the dry tropical forest of Colombia at three sites: 1) The Natural Reserve of Civil Society Campoalegre, Municipality Los Cordobas, Department of Cordoba (8.48502°N, 76.19520°W, WGS84; elev. 120 m); 2) Finca Los Mameyales, Municipality Piojó, Department of Atlántico (10.74480°N, 75.09279°W, WGS84; elev. 206 m); 3) Las Delicias farm, Municipality Aracataca, Department of Magdalena (10.58694°N, 74.14224°W, WGS84; elev. 197 m). We examined 28 stomachs of P. venusta collected during 0800–1200 h and 1600–1800 h within forests and disturbed areas. Samples were obtained during 2007 in the dry season (January–March), first rains (April–June), and heavy rains (September–December). SUL (mm), and maximum mouth width (mm) were recorded for each individual. We identified prey to lowest taxonomic level possible (family and genus), and their length and width were measured (complete prey only) using a digital caliper (nearest 0.1 mm). The individual volume of each prey item and the number of prey items per stomach for each prey category were recorded. Volume of each prey item was estimated using the formula of a prolate spheroid. Of the captured frogs, six were females and 22 were males (mean SUL = 67.60 ± 8.76 mm; mean mouth width = 21.76 ± 2.10 mm). The diet consisted of 16 types of prey and was dominated in volume and frequency by orthopterans. Acarina showed the highest numerical contribution (Table 1). It has been suggested that acariphagia occurs in small anurans in terrestrial habits. However, P. venusta is large and arboreal, suggesting that acariphagia is a trophic phenomenon not limited to the species defined by Simon and Toft (1991. Oikos 61:263–278). The large numbers of orthopterans and blattarians consumed are congruent with that reported for other Phyllomedusa spp. (Parmelee 1999. Sci. Pap. Nat. His. Mus. Univ. Kansas 11:1–59; Vaz-Silva et al. 2004. Herpetol. Rev. 35:160; Freitas et al. 2008. Biota Neotrop. 8:101–110). Considering the type and prey proportion, P. venusta appears to be a generalist predator with a sit-and-wait foraging strategy.Fil: Blanco Torres, Argelina. Universidad Nacional de Colombia; ColombiaFil: Duré Pitteri, Marta Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Bonilla, M. A.. Universidad Nacional de Colombia; Colombi

Variación espacial y temporal de la herpetofauna en ecosistemas de sabanas inundables de la Orinoquía-Colombia

Se comparó la diversidad de anfibios y reptiles en bosques de vega, de galería y sabanas y entre las épocas seca y de lluvias en ecosistemas de sabanas inundables. Se realizó un muestreo en tres sitios en cada época climática, mediante los métodos de encuentro visual y trampas de caída con barreras de interceptación. El esfuerzo de muestreo para cada cobertura fue de 252 horas de recorridos y 504 horas de trampas de caída. Se registraron 23 especies de anuros y 37 especies de reptiles: 10 serpientes, 13 lagartos, un anfisbénido, cuatro tortugas, y un cocodrilo. La mayoría son nuevos registros para la zona nororiental del departamento de Casanare. La mayor riqueza y abundancia se reportó en las sabanas. El clima no es una variable determinante en la riqueza, pero si en la abundancia de la herpetofauna. Las sabanas son de gran importancia para el mantenimiento de la estructura de los ensamblajes de herpetofauna a lo largo del ciclo anual, los bosques son zonas de refugios de diversidad durante el periodo de inundación.We compared the diversity of amphibians and reptiles in forest of vega, gallery forest and savannas in flooded savannas ecosystems. One sampling was conducted at three sites in each climatic season, using visual methods and encounter barriers of interception with pitfall traps. Sampling effort for each type of vegetation was 252 hours, and 504 hours of pitfall traps. A total of 23 species of anurans and 37 species of reptiles (ten snakes, thirteen lizards, one worm lizard, four turtles and one crocodilian) were recorded. Most are new records for the northeastern region of Casanare department. The greatest richness and abundance of herpetofauna were found in savannas. The weather is not a determining variable in the richness but in the abundance of the herpetofauna. Savannas are very important for maintaining the structure of herpetofauna assemblages throughout the annual cycle, forests are areas of maintenance of diversity during the flood period

Dieta de Craugastor raniformis Boulenger (Anura: Craugastoridae) en un area con bosque seco tropical del norte de Colombia

We characterize the diet of Craugastor raniformis, a terrestrial frog that inhabits the tropical dry forest in Colombia. The diet is constituted mostly of orthopterans, millipedes, arachnids and ants. Considering the morphological characteristics of this species, diet composition, gut vacuity index, trophic niche breadth and diversity, we consider this species would behave like a sit and wait predator