Abstract
Greater Vasa Parrots (Coracopsis vasa) are unique and enchanting birds, although drably, dully and funearally plumaged in shades of soot, charcoal, and plain old dirty grey and blessed with a stentorian, unoiled hinge/demented donkey type voice. They are not exactly birds which delight either the eye or ear, however, their lack of rainbow hues and dulcet tones are the only negative things that can be said about them. Large, well proportioned and (in repose), elegant, they are active and engaging birds with very distinct characters and behavior.
Native to Madagascar and the Comoros Islands, they are described by Forshaw (Parrots of the World, 197 3) as being "found in the forests and savannah below 1,000 metres, being more abundant at lower altitudes (Rand, 1936)", and on the Comoros "Benson (1960) found that they are largely dependent on evergreen forests above 300 metres, frequently visiting open country to feed but probably not remaining there permanently''.
All of our birds appear to be of the nominate form Coracop sis vasa uasa, which are confined in the wild to eastern Madagascar.
Salt Lake City is fortunate in having an avicultural society which maintains an Endangered Species Committee. One of the functions of this committee is to acquire rare birds for placement in one of three regional zoological collections, in a concerted effort to develop breeding programs for these species. Greater Vasa Parrots were selected as the initial project species, primarily because of their (limited) island distribution with its concommitant ''threatened'' status, its avicultural rarity and the sudden flux of availability.
With funds raised by the Endangered Species Committee, a pair of birds was purchased in August of 1986. The hen of this pair, though clearly bonded to her mate and showing her breeding condition in her naked, yellow-skinned head, was incapable of flight, tailless and had a grossly deformed leg. Her most serious affliction, however, and the one which decided us to return her to the vendor was her heavily pied appearance. Available avicultural references and the "grapevine" indicate that this partial albinism is indicative of ongoing, increasing and debilitating metabolic dysfunction. Her replacement, a bird in good, though nonbreeding, condition was promptly sent upon her return.
A second, immaculate pair was obtained from the Lin-Deco Bird Farm in Florida on October 3rd, 1986 and acquired by the Tracy Aviary.
All of these birds were surgically sexed prior to shipment, as there is no sexual dimorphism apparent. The second pair was not so large as the first and gave us all the clear impression of being quite young birds, although they did not display the juvenile plumage described by Forshaw, "general plumage more brownish, feathers of underparts edged with chestnut, grey bill".
The "young" pair was placed in an aviary 10 x 6 x 8 feet high attached to a heated shelter 6 x 6 x 8 feet high with a sand floor inside and out, furnished with large sycamore (Platanus americanum) perches and a medium size garbage can nest box hung inside. Sharing the flight were a pair of Redlegged Partridge (Alectoris rufa).
The adult birds were placed in a large, triangular shaped aviary eight feet high, six feet wide at its narrowest point (leading into the 6 x 15 x 8 foot shelter), 30 feet long and 20 feet wide at its base. Perched in stout Sycamore with a turf covered exterior and sanded inside, this pair was provided with a 12" x 12" x 36" nest box in their shelter and a medium size garbage can outside. This pair shared their flight with two male Black Korhaan Bustards (Afra afroides).
The young pair have always been compatable. They have been seen at times playing like puppies, rolling around on the ground, growling and playing with twigs and with each other. They are much more frequently vocal than the adult pair and seem prepared to vigorously feed each other at any time of the year. The male (who is a little larger than the female in this pair) boisterously bounces around from perch to perch, braying loudly as he goes, lands suddenly by the female, grabs her bill and pumps his head in a feeding manner. Copulation has never been seen, neither bird has ever become bald and, despite long periods spent in the nest box, no eggs have been laid by this pair.
The adult pair have totally different characters. Although not nervous, they are much more secretive and sedate than the young pair (possibly due to being wild-caught adults as opposed to wild-caught babies or juveniles). The pair has never bonded. Worse, the female has intermittently harrassed the male into oven-ready baldness over his entire body, i.e., the male has plucked himself down to the skin as a stress reaction to the female's attitude. We have twice removed him from the aviary, whereupon he has allowed his plumage to regrow perfectly. We have also tried removing the female from the aviary with a similar regrowth of feathers in the male. Curiously, she has never been seen to attack the male physically, simply intimidate him with voice and posture.
This hostility was not immediately evident. In fact, three months after the pair was acquired, we started finding small quantities of what looked like regurgitated seed on the floor of their cage. Considering their apparent good health, we believed that courtship feeding was taking place when the keeper was not present. (Hindsight, of course, leads us to think that maybe the male had been throwing up through stress!)
However, the female, 13 months after we obtained her, started to spend increasing periods of time inside the nest box in the shelter. On the rare occasions she was visible, it could be seen that she was becoming increasingly bald. She was totally bald from cere to nape and down to eye level on the sides of her head by the....