El Pitirre Volume #9 (3) Pages 5-6
Journal of “the Society Of Caribbean Ornithology”
An Unknown Parakeet on Hispaniola
by P. William Smith
P.O. Box 901341, Homestead, FL 33090, USA
In early afternoon of 26 March 1996, Larry Manfredi and I were driving down from the higher elevations of the Sierra de Bahoruco in southwestern Dominican Republic. About 9km east of El Aguacate border post on the road to Puerto Escondido, in a transition zone between mesic and xeric forest types at 500 m above sea level (a.s.1.), a passing hawk disturbed a large group of psittacines nearby. A flock of 10 parakeets (Aratinga) settled in a dead tree next to us. We soon realized that they were not Hispaniolan Parakeets (a. chloroptera), which now occur mostly at higher elevations in this region (Dod 1992; pers. obs.), but instead showed characters of the Olive-throated Parakeet (A. nana), a species found in Jamaica and Central America (Bond 1961, American Ornithologists’ Union 1983). None of the birds showed red anywhere, and all had largely burnt-olive underparts of subtly different shading. Otherwise the birds were mostly rich green (including lower flanks and undertail coverts), with blue flight feathers and long tails which were green above, yellowish-olive below. The orbital region was white and the beak pale horn. We returned to the area the following day and found at least as many similar birds about 2 km farther east, 10 km west of Puerto Escondido. They were mostly in pairs, feeding on the ripe fruit of gumbo limbo trees (Bursera simaruba).
The Olive-throated Parakeet is considered by some authorities to consist of two species, the Jamaican Parakeet (A. nana; sensu stricto) and the Aztec Parakeet (A. astec) of Mexico and Central America (e.g., Howell and Webb 1995). The differences between these taxa, which even Bond (1940) once considered separate species, are subtle and primarily based on measurements and color tones. Our descriptive notes seem inadequate to assign the birds we saw definitely to one form or the other, if indeed they should be assigned to either.
The Jamaican Parakeet is a fairly common and widespread resident of Jamaica, which lies about 200 km west of the westernmost point in Hispaniola and about 500 km west of the location where we saw these birds. Psittacines generally show diagnosable differences among insular populations, and it is unlikely that they can achieve lengthy overwater dispersal or vagrancy facilely (Wiley 1993). Such an explanation probably is unlikely to account for nana-like birds on Hispaniola.
If these birds themselves were released on Hispaniola or are descendants of birds released there in recent years, it would seem more likely that they would be Aztec rather than Jamaican Parakeets. Far more cage bird traffic originates in Central America than in Jamaica, where the Wildlife Protection Act prohibits capture or exportation of native birds (C. Levy, pers. comm.). A release might have been unintentional, even from a passing ship, and thus be untraceable. It also might have occurred in nearby Haiti, perhaps as a result of civil unrest there.
The most intriguing possibility is that these birds represent a relict of an ancient population on Hispaniola, hitherto overlooked. The parakeets were in a mostly xeric environment in an area where little collecting was done historically, at an elevation below the usual more mesic habitat of A. chloroptera. The nearest lower-elevation specimen of the Hispaniolan Parakeet apparently is from Polo, at 600 m a.s.1. about 50 km southeast of our observations (Wetmor and Swales 1931). Since several other avian genera or species show modern links in the Greater Antilles between only Hispaniola and Jamaica (e.g. Hyetornis, Siphonorhis, “ Kalochelidon,” Elaenia fallax, Myiarghus stolidus), an avifaunal link between those islands evidently existed at one time.
It may be fairly easy to resolve any question of these parakeets’ origin by collecting a small series and studying their skins against all known populations of Olive-throated Parakeets. If distinctive, then presumably they would represent long-isolated relicts. If like Aztec Parakeets, almost certainly they would have been released on the island. If like Jamaican Parakeets, however, it may be difficult to be certain how they got there. I hope Dominican wildlife authorities or others will begin this process. If distinct, almost certainly these parakeets are in need of protection. If exotic, on the other hand, perhaps they should be eradicated to protect the native A. chloroptera.
I thank Bill Beaty for facilitating our trip to Hispaniola, Storrs Olson and Bill Robertson for commenting on earlier drafts of this manuscript, Catherine Levy for updating me on wildlife law and practice in Jamaica, and Larry Manfredi for his companionship, especially for insisting that we study these parakeets carefully rather than simply pass them off as A. chloroptera.
American Ornithologists’ Union. 1983. Check-list of North American birds, sixth edition. AOU, Washington, D. C.
Bond, J. 1940. Check-list of birds of the West Indies. Academy of Natural Sciences, Philadelphia, Pennsylvania.
Bond, J. 1961. Birds of the West Indies, First American edition. Houghton Mifflin , Boston, Massachusetts.
Dod, A. S. 1992. Endangered and endemic birds of the Dominican Republic. Cypress House, Ft. Bragg, California.
Howell, S. N. G., and S. Webb. 1995. A guide to the birds of Mexico and northern Central America. Oxford University Press, Oxford.
Wetmore, A., and B. H. Swales. 1931. The birds of Haiti and the Dominican Republic. U. S. Nat. Mus. bull. 155.
Wiley, J. W. 1993. Natural range expansion and local extirpation of an exotic psittacine -- an unsuccessful colonization attempt. Ornitol. Neotrop. 4:43-54.