2 research outputs found
Figure 1 in Diet composition of an invasive population of Lithobates catesbeianus (American Bullfrog) from Argentina
Figure 1. (A) Location of studied invasive population of Lithobates catesbeianus from San Juan (black dot); (B) typical environment where the bullfrogs were captured for this study, around the Castaño Viejo River.Published as part of Quiroga, Lorena Beatriz, Moreno, MarĂa Daniela, Cataldo, Ariel AnĂbal, AragĂłn-Traverso, Juan HĂ©ctor, Pantano, MarĂa Victoria, Olivares, Juan Pablo Segundo & Sanabria, Eduardo Alfredo, 2015, Diet composition of an invasive population of Lithobates catesbeianus (American Bullfrog) from Argentina, pp. 1703-1716 in Journal of Natural History 49 (27) on page 1705, DOI: 10.1080/00222933.2015.1005711, http://zenodo.org/record/400192
Diet composition of an invasive population of Lithobates catesbeianus
The American bullfrog Lithobates catesbeianus has been introduced around the world, with invasive populations reported from almost all South American countries. A population of this species was introduced in the Calingasta department of San Juan province, which is an arid environment in western Argentina. This work provides information on the dietary composition of an invasive population of L. catesbeianus, and compares the degree of dietary overlap between adults and juveniles. Stomach contents of 169 bullfrogs (82 adults and 87 juveniles) were analysed. Adults consumed 40 prey taxa and Hymenoptera (Insecta) was the most numerous prey item (41.8%), followed by Araneae (13.6%) and Aeglidae (13.4%). Juveniles consumed 29 prey taxa and Hymenoptera constituted the highest percentage in prey number (77.2%). The trophic overlap niche index at the same level shows a value of 0.64 overlap in dietary community between adults and juveniles of this bullfrog. Aeglidae was volumetrically the most important trophic item (25.4%), followed by Anura (25.02%). Our results showed that cannibalism in bullfrogs is more common than the consumption of native anurans, coinciding with that reported in other populations of introduced bullfrogs. The high similarity in the diets of both size classes and the association between the size of the predator and prey suggest that the impact caused by bullfrogs throughout their ontogeny is high andprobablyhasanimpactontheirprey.Freshwatercrabsarethemainitemsinthe diet of Lithobates catesbeianus in other introduced populations and are usually the most conspicuous at our study site. The crabs in freshwater ecosystems are part of the lowest trophic level in the food chain. The major threats to the southern regionâs freshwater crabs include deforestation, farming and exotic species. Lithobates catesbeianus has a generalist diet and high overlap between adults and juveniles.Fil: Quiroga, Lorena Beatriz. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - San Juan; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas FĂsicas y Naturales. Departamento de BiologĂa; ArgentinaFil: Moreno Avila, MarĂa Daniela. Universidad Nacional de San Juan. Facultad de Ciencias Exactas FĂsicas y Naturales. Departamento de BiologĂa; ArgentinaFil: Cataldo, Ariel Anibal. Universidad Nacional de San Juan. Facultad de Ciencias Exactas FĂsicas y Naturales. Departamento de BiologĂa; ArgentinaFil: Aragon y Traverso, Juan HĂ©ctor. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - San Juan; Argentina. Universidad Nacional de San Juan. Facultad de Ciencias Exactas FĂsicas y Naturales. Departamento de BiologĂa; ArgentinaFil: Pantano, MarĂa Victoria. Universidad Nacional de San Juan. Facultad de Ciencias Exactas FĂsicas y Naturales. Departamento de BiologĂa; ArgentinaFil: Olivares Toselli, Juan Pablo Segundo. Universidad Nacional de San Juan. Facultad de Ciencias Exactas FĂsicas y Naturales. Departamento de BiologĂa; ArgentinaFil: Sanabria, Eduardo Alfredo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - San Juan; Argentina. Universidad Nacional de San Juan. Facultad de FilosofĂa, Humanidades y Artes. Instituto de Ciencias BĂĄsicas; Argentin