Ontogenetic variation in the diet of the anuran community from a semi-arid environment in the southeastern Chihuahuan Desert

Abstract

Although ontogeny influences dietary composition and trophic niche breadth in many anurans, its effects on diet have been little analyzed in sympatric species. In this study, we analyzed interspecific and ontogenetic variation in dietary composition and trophic niche width in an anuran community from a semi-arid environment. We found a more profound effect of species identity than body size on dietary composition, with the diet of four species dominated by formicids, that of two others by coleopterans and formicids, and that of the remaining species not dominated by specific prey types. We found ontogenetic changes in dietary composition in three of four species analyzed, in which consumption of some small insects decreased as predator size increased, regardless of species. Additionally, we did not find ontogenetic change in prey number consumed in any of the four species, but prey size increased with increasing predator size in all of them. Most species exhibited a narrow trophic niche, which was even narrower in adults in three of the four species analyzed. Costello’s modified plots revealed a high variation among individuals in termite consumption in Anaxyrus punctatus, and in more prey types in Spea multiplicata. Our results suggest that this community is not size-structured, and that ontogenetic diet shifts are mainly caused by passive sampling toward prey of different sizes. Finally, comparisons with previous data revealed an interpopulation pattern, in which trophic niche width contracts as aridity increases, possibly because of an increase in interspecific competition for trophic resources.

Non‐native stinging ant interactions with native anurans

“…Given that prey type and size sometimes, but not always, correlates with anuran body size (Bush & Menhinick, 1962; Luría‐Manzano & Ramírez‐Bautista, 2019; Womack & Bell, 2020), we measured the body size of each individual anuran [snout–vent length (SVL)].…”

“…Given that prey type and size sometimes, but not always, correlates with anuran body size (Bush & Menhinick, 1962;Luría-Manzano & Ramírez-Bautista, 2019;Womack & Bell, 2020) The anurans were housed individually in glass terrariums. The terrariums were lined with loose coconut fibre and each contained a plastic water dish and a plastic hide.…”

Respuestas de la diversidad taxonómica y funcional a la transformación del paisaje: relación de los ensamblajes de anfibios con cambios en el uso y cobertura del suelo

“…Además, esta especie, aunque se asocia a la vegetación riparia (Rueda-Almonacid et al, 2004), no depende de los cuerpos de agua para su reproducción (modo reproductivo de desarrollo directo), rasgo que facilita utilizar coberturas como algunos cultivos con cierta estructura vegetal que le permita refugiarse de la acción directa del sol y el viento. Hay que considerar la variación ontogenética en la identidad de las especies, su dieta y tamaño corporal, dado que es en las interacciones bióticas (inter e intraespecíficas) donde se estructuran finalmente los ensamblajes (Blüthgen, 2010;Luría-Manzano y Ramírez-Bautista, 2019b).…”

Exploring temporal patterns in fish feeding ecology: Are ontogenetic dietary shifts stable over time?

“…An important handicap for the current knowledge regarding theory and key concepts in trophic theory is related to the sampling efforts and duration of research programs. Studies on, e.g., insects, amphibians, reptiles, mammals, and fishes typically cover short time frames spanning from one to a few consecutive years (e.g., Eloranta et al 2010;Klecka and Boukal 2012;Schriever and Williams 2013;Luría-Manzano and Ramírez-Bautista 2019), whereas studies using long-term perspectives are scarcer in the literature despite some noteworthy exceptions from freshwater (e.g., L' Abée-Lund et al 2002;Saksgård and Hesthagen 2004;Winfield et al 2012;Riccialdelli et al 2013;Hanson et al 2018) and marine (e.g., Michalsen et al 2008;Holt et al 2019;Townhill et al 2021) fish model organisms. Overall, long-term studies constitute a small fraction (5-6%) of research efforts in aquatic systems (Xenopoulos 2019).…”