Forage use in domestic cattle (Bos indicus), capybara (Hydrochoerus hydrochaeris) and pampas deer (Ozotoceros bezoarticus) in a seasonal Neotropical wetland

The impact of livestock grazing on native wildlife remains a topic for considerable debate. In the Brazilian Pantanal extensive cattle ranching has been practised since the mid-18th century and cattle live alongside a diverse group of medium to large sized terrestrial mammalian herbivores. This study examined the use, similarity and selection of forage resources among cattle (Bos indicus), pampas deer (Ozotoceros bezoarticus) and capybara (Hydrochoerus hydrochaeris) in a paddock in the central region of the Brazilian Pantanal. Plants consumed were identified through micro-histological analysis of faecal samples collected from three species over several seasons, and quadrats (0.5 m × 0.5 m) were allocated to patches within each of the main landscapes to measure availability of resources. Overall, cattle were classified as grazers, capybara as mixed feeders, pampas deer as browsers. 126 plants were identified in faecal samples of the three species. Similarity indices were highest between domestic cattle and the capybara and lowest between these two species and the deer. Diets were more similar between the species during the wet season (period of resource abundance) than during the dry season (period of resource scarcity). Overall animals selected different forage species H. amplexicaulis and L. hexandra were the only plants selected by all three herbivores. In this study, the presence of cattle does not appear to be as detrimental to wild herbivores as suggested by other examples in the literature.