Habitat preferences of lesser rheas in Argentine Patagonia

BELLIS L. M,; NAVARRO J.L.; VIGNOLO P.E.; MARTELLA M.B.

BIODIVERSITY AND CONSERVATION

SPRINGER

Año: 2006 p. 3065 - 3075

0960-3115

This work reports the first results of a 3-year study (1998 – 2001) on habitat use andpreferences by wild lesser rheas (Rhea pennata pennata) in the ecotone Monte–Patagonian steppe ofArgentina. Ponds and four different habitat alternatives for lesser rheas were determined usingsatellite images and different structural vegetation characteristics: steppe, shrubland, shrub steppe,and mallines. Lesser rheas (adults, juveniles and chicks) used all habitats available to feed, althoughthey showed preference for mallines, open areas that offer good visibility and abundant foodresource. Rheas used shrub steppe and steppe for nesting, but they did not show preference foreither habitat type. Nest site had a higher percentage of vegetation cover than control sites. Lesserrheas apparently preferred concealed sites for nesting since they offer protection from severe climateconditions and from predators. Our results suggest that habitat preference by lesser rheascounterbalances profitability of feeding to the corresponding cost of predation..