Niche overlap and resource partitioning among five sympatric bufonids (Anura, Bufonidae) from northeastern Argentina

The niche overlap and resource partitioning were analyzed for five sympatric bufonids from Northeastern Argentina: Rhinella schneideri, R. bergi, R. fernandezae, R. granulosa, and Melanophryniscus cupreuscapularis. The primary objectives were to analyze the diet and pattern of coexistence relative to the microhabitats among species. The bufonids, which are primarily terrestrial, exhibited a preference for small, hard prey such as formicids or coleopterans. The smallest species preferably consumed ants, while R. schneideri preferred beetles. Significant differences were detected for the diets of these five species. In addition, significant overlap in the trophic niche was noted for all species except between R. granulosa and R. schneideri. Studying the diet behaviors and trophic parameters of sympatric species provides important data for understanding the community and for the development of conservation guidelines.Analisamos a sobreposição de nicho e a partilha de recursos entre cinco cinco espécies simpátricas de bufonídeos do nordeste da Argentina: Rhinella schneideri, R. bergi, R. fernandezae, R. granulosa e Melanophryniscus cupreuscapularis. O principal objetivo foi analisar a dieta e o padrão de coexistência entre as espécies em relação aos micro-habitats. Os bufonídeos, primariamente terrestres, mostraram preferência por presas duras e de pequeno porte, como formigas e coleópteros. As espécies menores consumiram preferencialmente formigas, enquanto R. schneideri preferiu besouros. Foram detectadas diferenças significativas entre as dietas das cinco espécies. Além dis-so, houve sobreposição significativa entre os nichos tróficos de todas as espécies, exceto entre R. granulosa e R. schneideri. O estudo do comportamento alimentar e dos parâmetros tróficos de espécies simpátricas fornece dados importantes para a compreensão da estrutura das comunidades e para o delineamento de estratégias de conservação

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

Consideraciones ecológicas sobre la dieta, la reproducción y el parasitismo de Pseudopaludicola boliviana (Anura, Leptodactylidae) de Corrientes, Argentina

The main objectives of this paper were to update the distribution range of Pseudopaludicola boliviana in Argentina, to determine its diet composition and the feeding patterns, to analyze some reproductive variables as mature ova count and diameter in relation to female snoutvent length, to describe the advertisement call for Argentinean populations, and to identify and to localize its helminth parasites. Eleven prey types were identified; dipterans were more important both in number (23.53%) and in volume (41.30%); other important preys were collembolans, arachnids and coleopterans. The trophic niche width was 7.15 and the standardized trophic niche value was 0.61. Ovarian complement (number of mature ova for female) ranged from 50 to 319 (mean 175.3 ± 86.12), while ovum diameter ranged from 0.2 to 0.4 mm (mean 0.27 ± 0.062). The nuptial call is composed by five notes. The dominant frequency ranged from 3.488 to 5.927 kHz; emphasized frequency fluctuated between 4.942 and 5.224 kHz. A total of 10 helminth species (larvae and adults) were found in 54 (96%) infected frogs. Helminths were represented by Trematoda (7 species), Cestoda (1), Nematoda (1), and Acanthocephala (1)

Estructura trófica y aspectos ecológicos de los gremios de una comunidad de anfibios de la provincia de Corrientes

En el presente trabajo de tesis se estudiaron 26 especies de anuros correspondientes a las 4 familias (Microhylidae, Bufonidae, Leptodactylidae e Hylidae) presentes en la provincia de Corrientes, Argentina. La finalidad de este estudio fue determinar la manera en que las diferentes especies de una comunidad comparten y explotan sus recursos, para lo cual se consideraron los parámetros tróficos de cada una de ellas relacionándolos con el microhábitat que ocupan. Los lugares de colecta elegidos pertenecen a un área que se extendió 30 Km. al noroeste de la provincia de Corrientes (27°30' S, 58°45' O), en la zona comprendida entre las localidades de San Luis del Palmar, Paso de la Patria y la ciudad de Corrientes, con una extensión aproximada de 300 Km².Facultad de Ciencias Naturales y Muse

Trophic, reproductive and parasitological aspects of the ecology of Leptodactylus chaquensis (Anura: Leptodactylidae) in Argentina

We studied the trophic and reproductive ecology and document the helminth fauna of the Cei's white-lipped frog, Leptodactylus chaquensis, from north-eastern Argentina. This frog is a generalist predator, using an intermediate strategy between active foraging and sit and wait predation. The diet consisted of 17 types of prey and was dominated numerically and volumetrically by coleopterans. The number of mature ova per female (ovarian complement) ranged from 3113 to 16234, and the ovum diameter varied from 0.4 to 1.2 mm. The testes mass ranged from 0.32 to 1.54 g, and the species has an explosive reproductive pattern. The parasite fauna was rich, consisting of 20 species of helminths (twelve trematodes, one cestodes, six nematodes and one acanthocephalan), the kidneys, lungs and large intestine being the organs most infected. The trophic niche breadth and the habitats where this species is living structured the parasite communityFil: Kehr, Arturo Ignacio. 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: Hamann, Monika I.. 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: Kehr, Arturo Ignacio. 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: Gonzalez, Cynthya Elizabeth. 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: 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