Howler monkeys (Alouatta Lacèpéde, 1799) are folivores-frugivores with flexible diets depending on conditions. Here, we compare the diets of Alouatta caraya (Humboldt, 1812) in two riparian forests (island and mainland), in Porto Rico region, Upper Paraná River, Southern Brazil. Howlers were followed from October 2004 to September 2005 in the riparian forest of a 1,050 ha island and in the continuous riparian forest on the mainland (left bank of the river). The "scan sampling" method with instantaneous samples every 15 minutes was used. Besides vines, diet breadth was similar: 17 species consumed on the island versus 16 species on the mainland. Both consumed leaves followed by fruits more than any other food type (leaves: island - 65%, mainland - 49%,... |