Thesis (M.S.)--North Carolina State University, 2003. / Title from PDF t.p. (viewed on May 16, 2004). Includes vita. Includes bibliographical references (p. 58-63).

The following study is part of a larger study examining techniques that might be of use in the release program of the Puerto Rican Parrot (Amazona vittata), including marking, capturing, and radio-tracking. The portion of the study reported here documents the vocal behavior of A. vittata during the reproductive season and examines the possibility of using vocalizations to identify individuals, determine the sex of individuals and determine the location of an individual's breeding territory. Objectives of this study included: 1) cataloguing and categorizing the vocal repertoire of A. vittata, 2) determining whether the vocal repertoire was sex-specific and region-specific and 3) determining if an individual's vocal repertoire could be used to identify it. The vocal repertoire was characterized using a hierarchical method and 147 calls were described. The repertoire was found contain a high percentage (76 %) of graded calls. Evolutionary strategies that may explain the complexity of such a repertoire are discussed. The vocal repertoire was found to be both sex- and region-specific. Characteristics analyzed included time and frequency parameters of sonagrams. Three methods were used to determine the feasibility of vocal recognition of individuals. These methods included: bird-call pairing, sonagraphic analysis, and linear predictive coding. Sonagraphic analyses in combination with linear predictive coding techniques show the most promise as tools in voice recognition of the parrot, however, further research will be necessary to determine how reliable voice recognition may be as a method for identifying individuals in the field. / Master of Science

I determined abundance, movement and activity patterns of the Red-tailed Hawk (Buteo jamaicensis jamaicensis, RTHA) in Río Abajo Forest, Puerto Rico and surrounding lands during 2003-2004. Captive-reared Puerto Rican Parrots (Amazona vittata, PRPA) are scheduled for release in Rio Abajo Forest in 2006. Annual density of RTHAs (0.90 RTHAs/km2) was similar to the Caribbean National Forest (CNF; 1.29 RTHAs/ km2). RTHAs annual survival was high (0.89), and birds maintained compressed territories around the Rio Abajo Forest. Home ranges were 91% smaller than estimates reported for CNF, yet similar to those in North America. Approximately 98.3% of RTHA locations occurred outside the Río Abajo Forest boundaries. RTHAs exhibited random macrohabitat use patterns in north-central Puerto Rico. However, within their home ranges, RTHAs selected fragmented habitats with high patch and edge density, and avoided large tracts of dense closed canopy forest. Encounters between RTHAs and PRPAs may increase as parrots venture beyond the boundaries of Rio Abajo Forest.