title: Diet of a sigmodontine rodent assemblage in a Peruvian montane forest.
abstract: Knowledge of feeding habits of small rodents is necessary for understanding food webs, trophic structure, and plant-animal interactions in Neotropical forests. Despite several studies that have investigated community structure and feeding behavior of rodents, large gaps remain in our understanding of their guild occupancy. Our objective was to investigate the diets of 7 species of small (< 100g) sympatric sigmodontine rodents in a high (3,500 m) Andean montane rainforest in Peru. We qualitatively and quantitatively assessed diet items in fecal samples from livetrapped rodents from 2009 to 2012. Frequency data for 4 diet categories indicated that all 7 species of rodents contained 4 diet categories in fecal samples: arthropods (88%), remains of leaves and fibers from plants (61%), intact seeds (with or without fruit pulp; 50%), and mycorrhizal spores (45%). Omnivory was found to be a strategy used by all species, although contingency table analysis revealed significant differences among and within species in diet categories. Cluster analysis showed 2 main groupings: that of theThomasomysspp. plusCalomys sorellusgroup which included high amounts of intact seeds and plant parts in their fecal samples, and those of the generaAkodon,Microryzomys,Oligoryzomys, which included a greater proportion of arthropods in their fecal samples, but still consumed substantial amounts of fruit and plant parts. Intact seed remains from at least 17 plant species (9 families) were found in fecal samples. We concluded that this assemblage of sigmodontine rodents is omnivorous but that they likely play an important role as frugivores and in seed dispersal in tropical montane forests in Peru. El conocimiento de los hábitos alimenticios de roedores pequeños es necesario para comprender cadenas alimenticias, estructura trófica, e interacciones planta-animal en los bosques neotropicales. A pesar de que numerosos estudios han investigado la estructura de comunidades y el comportamiento de forrajeo en roedores, aún existen grandes vacíos en nuestra comprensión de sus gremios tróficos. Nuestro objetivo fue investigar las dietas de siete especies de pequeños (< 100 g) roedores sigmodontinos simpátricos en un bosque montano andino a 3.500] m en Perú. Cualitativamente y cuantitativamente evaluamos la dieta en muestras fecales de roedores capturados entre el 2009 y el 2012. Datos de frecuencia para cuatro categorías de dieta indicaron que las siete especies de roedores consumieron cuatro categorías de dieta: artrópodos (88%), pedazos de hojas y fibras de plantas (61%), semillas intactas (con o sin pulpa de frutos; 50%), y esporas de micorrizas (45%). Omnivoría fue la estrategia utilizada por todas las especies, aunque el análisis con tablas de contingencia reveló diferencias significativas entre y dentro de especies en categorías de dieta. El análisis de agrupación presentó 2 grupos principales: el grupoThomasomysspp. yCalomys sorellus, que incluye una gran proporción de semillas intactas, y partes de plantas en las muestras fecales y el grupo que incluye los génerosAkodon,MicroryzomysyOligoryzomys, el cual incluyó una proporción mayor de artrópodos en sus muestras fecales, pero con niveles altos de semillas intactas. Semillas intactas de al menos 17 especies de plantas (9 familias) fueron encontradas en las muestras fecales. Concluimos que este ensamble de roedores sigmodontinos es omnívoro y que probablemente las especies juegan un rol importante como frugívoros y en la dispersión de semillas en los bosques montanos tropicales en el Perú.
authors.affiliation: Andean and Marine Biodiversity Monitoring and Assessment Program, Center for Conservation Education and Sustainability, Smithsonian Conservation Biology Institute , 9099 Woodcrest Dr., Brecksville, OH 44141 , USA (CTS).
authors.forename: Catherine Teresa
authors.initials: CT
authors.lastname: Sahley
authors.affiliation: Andean and Marine Biodiversity Monitoring and Assessment Program, Center for Conservation Education and Sustainability, Smithsonian Conservation Biology Institute , 9099 Woodcrest Dr., Brecksville, OH 44141 , USA (CTS).
authors.forename: Klauss
authors.initials: K
authors.lastname: Cervantes
authors.affiliation: Andean and Marine Biodiversity Monitoring and Assessment Program, Center for Conservation Education and Sustainability, Smithsonian Conservation Biology Institute , 9099 Woodcrest Dr., Brecksville, OH 44141 , USA (CTS).
authors.forename: Victor
authors.initials: V
authors.lastname: Pacheco
authors.affiliation: Andean and Marine Biodiversity Monitoring and Assessment Program, Center for Conservation Education and Sustainability, Smithsonian Conservation Biology Institute , 9099 Woodcrest Dr., Brecksville, OH 44141 , USA (CTS).
authors.forename: Edith
authors.initials: E
authors.lastname: Salas
authors.affiliation: Andean and Marine Biodiversity Monitoring and Assessment Program, Center for Conservation Education and Sustainability, Smithsonian Conservation Biology Institute , 9099 Woodcrest Dr., Brecksville, OH 44141 , USA (CTS).
authors.forename: Diego
authors.initials: D
authors.lastname: Paredes
authors.affiliation: Andean and Marine Biodiversity Monitoring and Assessment Program, Center for Conservation Education and Sustainability, Smithsonian Conservation Biology Institute , 9099 Woodcrest Dr., Brecksville, OH 44141 , USA (CTS).
authors.forename: Alfonso
authors.initials: A
authors.lastname: Alonso
keywords: Akodon; Calomys; Microryzomys; Oligoryzomys; Sigmodontinae; Thomasomys; rodent frugivory; tropical forest