Conservation taxonomy, the study of organismal classification to clarify conservation priorities, seeks to define species and subspecies limits. Allopatric populations, such as those present on islands, pose special challenges to identifying taxonomic boundaries that can be be addressed using diagnostic criteria. Because some of the island populations of Cuban Parrot (Amazona leucocephala) are highly endangered, the five recognized subspecies need careful reevaluation. I measured 18 morphological and plumage characters from 188 museum specimens representing the six extant and one extirpated island populations. I also examined 11 spectrographic characters from the flight calls of 23 parrots representing all six extant populations. I relied largely on discriminate function analyses (DFA) to assess diagnosability and examine patterns of similarity among the populations.

Most morphological characters indicated sexual dimorphism, with males 1-4% larger than females. The plumage characters, in contrast, demonstrated complete absence of sexual dichromatism. Stepwise discriminant analyses including all specimens and 14 characters revealed substantial differentiation among island groups, with 81.4% of individuals classified correctly to island. Pairwise comparisons among islands showed reciprocal discrimination >80%, with the exception of Cuba/Cayman Brac (67%). Although currently lumped into a single subspecies, each of the three Bahamas populations (including an extirpated population) was equally distinct as the four other currently-recognized subspecies.

Parrots from each island possessed distinct flight calls, leading to full diagnosis for all but the Cuba/Isla de la Juventud populations. Diagnostic characters were usually qualitative (Abaco: paired syllables; Inagua: frequency jump; Cuba/Isla de la Juventud: subharmonics), but Cayman Brac calls had diagnostic syllables of long duration. Discriminant analyses indicated that the quantitative characters were most similar for Cuba, Isla de la Juventud, and Grand Cayman, with those from Abaco and Inagua (The Bahamas) and Cayman Brac being most distinct.

Collectively, the evidence supports the view that all island populations, including the extirpated population from Acldins Island (The Bahamas), warrant subspecies status. The Abaco population, which is unique among New World parrots in nesting on the ground, should be considered a candidate for elevation to full species. Current management practices should be revised to reflect the degree of diversity exhibited in this group.

LLU Discipline





School of Science and Technology

First Advisor

William K. Hayes

Second Advisor

Leonard Brand

Third Advisor

Kevin Nick

Degree Name

Master of Science (MS)

Degree Level


Year Degree Awarded


Date (Title Page)




Library of Congress/MESH Subject Headings

Parrots -- Conservation; Parrots -- Ecology; Parrots -- Flight; Parrots -- Cuba.



Page Count

xi; 57

Digital Format


Digital Publisher

Loma Linda University Libraries

Usage Rights

This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.


Loma Linda University Electronic Theses and Dissertations

Collection Website



Loma Linda University. Del E. Webb Memorial Library. University Archives

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