FORAGING PATTERNS OF CAPYBARAS IN A SEASONALLY FLOODED SAVANNA OF VENEZUELA

The foraging behaviour of capybaras (Hydrochaeris hydrochaeris) was as sessed in relation to habitat and season in a flooded savanna of Venez uela from February (dry season) 1993 to June (rainy season) 1994. Dire ct observations were carried out to record group movements and foragin g activities of individual capybaras when feeding on specific plant sp ecies. The time devoted to feeding upon some species was recorded in r elation to total foraging time (feeding + searching). Capybaras spent similar times feeding on reeds (Eleocharis interstincta; Cyperaceae) a nd Paratheria prostrata (Poaceae) patches during the dry season though plant quality was different. During the rainy season, reeds were almo st ignored by the animals which fed mainly on Hymenachne aplexicaulis, a grass with a significantly higher content of energy and protein. Ca pybaras fed for longer time during the dry season but more selectively during the rainy season. Capybaras were the dominant grazers in this flooded savanna as inferred from the comparative effects they produced in the height, biomass and quality of the pasture in relation to thos e effects produced by other vertebrate herbivores, namely, cattle, fer al horses and asses.