The Collaborative International Dictionary of English v.0.48:

Chachalaca \Cha`cha*la"ca\, n. [Native name, prob. given in
   imitation of its cry.] (Zool.)
   The Texan guan (Ortalis vetula). [written also
   chiacalaca.]
   [1913 Webster]

WordNet (r) 3.0 (2006):

chachalaca
    n 1: slender arboreal guan resembling a wild turkey; native to
         Central America and Mexico; highly regarded as game birds