Hoarding patterns of sigmodontine rodent species in the Central Monte desert (Argentina).

GIANNONI, S. M.; CAMPOS, V.; ANDINO, N.; RAMOS CASTILLA, M.; OROFINO, A. ; BORGHI C.E.; DE LOS RÍOS, C.; CAMPOS, C. M.

AUSTRAL ECOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2012

1442-9985

Hoarding food is an important strategy of rodents in desert environments characterized by unpredictable and poor food resource availability. In the Monte desert, Prosopis produces abundant food, unevenly in time and space, in the form of pods and seeds. Sigmodontine rodents (Graomys griseoflavus, Akodon molinae, Eligmodontia typus, and Calomys musculinus) use Prosopis propagules extensively, and they could be predators or dispersers depending on how they handle and where they leave the propagules. The objectives of this study were: 1) to know what rodent species transported propagules; 2) to evaluate what hoarding pattern was used by species that transport propagules (larder and scatterhoarding); and 3) to analyze in which condition were propagules left by the rodent species, both at the food source and in caches. Our results showed that all four species transported propagules, with G. griseoflavus and E. typus being the species that carried more seeds. Our study supported the evidence that food caching is common among species and that many species both larderhoard and scatterhoard food. G. griseoflavus and A. molinae, the largest species, larderhoarded more than did the smaller E. typus. These results uphold the hypothesis that larger species will show greater propensity to larderhoard than smaller species. Considering the interaction between seed-hoarding patterns and plants, E. typus was the species that could most improve germination because it scatterhoarded propagules and left seeds out of pods. In contrast, G. griseoflavus could have a negative impact on plant populations because this was the species that predated more seeds and larderhoarded a high percentage of them. The smallest C. musculinus was the species that less transported propagules, and left them as seeds inside pods or pod segments mainly at the food source, which makes seeds more vulnerable to predation.