Structure and Composition of Wild Black Howler Troops (Alouatta caraya) in Gallery Forests of the Argentinean Chaco

Abstract

The genus Alouatta occurs from the south of Mexico to northern Argentina and from the South American Pacific Coast to the Brazilian Atlantic Forest. A. caraya is the southernmost species, inhabiting central and southern Brazil, eastern Bolivia, Paraguay, and northern Argentina. Although there are adequate demographic data from populations in the forests of the Río Paraná in Argentina, the data are comparatively limited for populations in the Argentinean Chaco. In this preliminary study we describe the composition and structure of wild troops of A. caraya that inhabit the gallery forests along the Riacho Pilagá in Formosa Province and compare them with data obtained from this area two decades ago.