Diet Selection by the Fossorial Rodent Ctenomys mendocinus Inhabiting an Environment with Low Food Availability (Mendoza, Argentina)

Abstract

Abstract The seasonal diet of Ctenomys mendocinus was determined in a habitat of the Andean Precordillera, through microhistological analyses of stomach contents and in relation to food availability. Diet included 23 genera of plants and only 6 of them were consumed with frequencies higher than 4%. The grasses Stipa and Elymus comprised about 80% of the diet. A high proportion of aerial plant material was registered throughout the year suggesting a tendency to forage on the surface. Dietary selectivity was evidenced by a preferential consumption of grasses and avoidance of shrubs. Moreover, most dietary items frequently used were eaten in proportions that differed from their availabilities. This non-opportunistic feeding behavior, specialized in a few dietary items, did not agree with the one expected for a subterranean rodent inhabiting an environment with severe climatic conditions, low food availability and patchy distribution of food resources.