CONICET | Buscador de Institutos y Recursos Humanos

The lesser rhea (family Rheidade) is a fightless large bir of South America, threatened due to habitat loss, hunting and egg collecting, with special concern in Northern Patagonia. Diet and food availability were estimated throughout the year by micro-histological analysis and point-quadrad transects in a landscape inside and another outside the Payunia Reserve, the northernmost part of the Rhea pennata pennata distribution. Significant differences were detected by Kruskall-Wallis ANOVA, food selection by Chi-square test and Bailey´s confidence interval. A strong food selection charactherized the diet of lesser rheas, dominated by leaves of shrubs and forbs, complemented by dicot seeds and a few insects overlap with other herbivores in Payunia. Dietary changes agree with the expeted from the selective quality hypothesis. Food availability was better inside than outside the proteted area, with probable conservation effects for lesser rheas. Seeds, forbs and soft grasses could be for lesser rheas some key food resources to survive during unfavorable season in arid environments without "mallines " as Payunia . Shrubby patches, with high availability of preferred food items (tall shrubs and forbs), stood out as key habitats. Therefore, avoiding fire and woody plant removal is crucial for the conservation of lesser rheas in the northern of its range.