Indirect estimation of landscape uses by Lama guanicoe and domestic herbivorous through the study of diet composition in South Patagonia

G MARTÍNEZ PASTUR; R SOLER ESTEBAN; MV LENCINAS; L BORRELLI

PORTUGAL

Conferencia; Landscape ecology conference; 2010

Herbivory is central in ecosystem function studies, and herbivores through browsing influence over regeneration and vegetation composition. Understanding diet selection behaviour along the year is important to predict herbivore impacts on regeneration and vegetation dynamics under different scenarios of forest and grazing management. The objective was to evaluate diet composition of herbivorous, and correlate them to the use of different vegetation types along the year. The study was conducted in 100 km² of Tierra del Fuego Island (Argentina) where 205 floristic surveys were obtained. Feces of native (Lama guanicoe) and domestic (Bos taurus and Ovis aries) herbivorous were collected. Four laboratory samples per species and season were analyzed, each one composed by five fecal collection. Samples were mixed, dried and ground in a mill (1 mm) for microhistological analysis. Browsing occurred all around year, where native and domestic herbivorous alternate the uses of different environments. Native species preferred Nothofagus pumilio forests, except in winter, where domestic species had major predominance. Beside this, all the herbivorous species included grasses founded in open environments (grasslands and peatlands) in their diet. The knowledge of diet and plant distribution at landscape level allows us to propose management strategies for native and domestic herbivorous.