Abstract
Golden-headed quetzals (Pharomachrus auriceps) are strikingly beautiful members of the Trogon family. They inhabit humid cloud forests of the sub-tropical portions of the Andes range in Venezuela, Colombia, Ecuador, Peru and northern Bolivia. (This is a colder, wetter environment than the habitat of their more familiar and glamorous relative, the resplendent quetzal (Pharomachrus mocinno).) All quetzals are arboreal and according to published reports, their diet in the wild consists mainly of small avocado-like fruits, lizards and insects. Nests are located in rotten tree cavities and the birds themselves are rather secretive and sedentary. The average length of P auriceps is 35 cm. Females are somewhat duller versions of the males, lacking extensive iridescent coloration on their heads, and having less elaborate development of the rump and tail feathers. In addition, the beak coloration is dark brown in females and juveniles and bright golden yellow in adult males. The Trogon family consists of eight genera and 34 species (20 New-World, 11 Asian and three African). The quetzals comprise the neo-tropical genus Pharomachrus. As with all other members of this unique family, with the exception of a few individuals, quetzals have generally proven difficult to establish and maintain in captivity. As a result, they are seldom available and few specimens have been exhibited in zoos or maintained in private collections. We were, therefore, not surprised when a review of the literature indicated that of the 34 trogon species, only one successful breeding has been reported in captivity: the resplendent quetzal in a private collection in Costa Rica in 1941 (Delacour, 1943).
Of all loosely defined grouping of bizarre and unusual birds known as softbills, my personal interest has always focused on four distinct families: touracos (Musopbagidae), birds of paradise (Paradisaeidae), cocks of the rock (Cotingidae), and trogons (Trogonidae).
Earlier in my zoo career, I was fortunate to have the opportunity to work with and successfully breed representatives from all of these groups with the exception of the trogons. I was, therefore, quite excited when in December of 1981, we were able to acquire a single female of P auriceps for the zoo's collection from Hendee Zoological in Chicago. We were assured at the time the female was purchased that a male would be available in the near future. We were hopeful, and even somewhat optimistic, that we could breed this species provided, of course, that we could keep them alive.
Upon her arrival, the female quickly proved that quetzals are, indeed, delicate and tedious birds to maintain. The zoo quarantine period was difficult for both this female and her keepers. The diet instructions received from Hendee consisted of: cubed whole wheat bread, puffed rice cereal, chopped banana, avocado, soaked dog chow and a vitamin/mineral supplement. These were the only items they had been able to persuade her to eat. We soon learned, to our dismay, that these were eaten none too well.
This particular specimen was unbelievably sedentary. In fact, I often wondered, when I observed her through the window of the quarantine ward, if she was indeed alive or whether her keepers, in fear of my not uncommon fits of rage, had taken her carcass to a taxidermist and were simply moving her realistically-stuffed body from perch to perch in a daily basis. As the Houston Zoo had previously received a degree of notoriety in the press for exhibiting fake coral snakes my suspicions in this direction were not totally unfounded.
In March of 1982, a juvenile male was received from Hendee. This bird was placed in our quarantine building in a flight adjacent to the female. By then, with our now somewhat vast experience associated with the stresses and traumas oftrogan husbandry, the male's conditioning and quarantine were relatively uneventful. This was perhaps due to the fact that he was a younger bird and seemed to adapt more easily to his captive environment. He accepted a broader range of diet items, occasionally flew around his cage, and even more amazingly, often vocalized. His animation did little, however, to stimulate the female, and I continued to think she might actually be a realistically mounted taxidermy specimen. Both birds completed their quarantine in mid-April and were subsequently transferred to the Tropical Bird House.
During their quarantine we noticed that the female's left eye was becoming cloudy and obviously she could not see well. Examination revealed that a cataract had developed. Due to her visual impairment, the decision was made not to release the pair into our large, mixed species, walk-through aviary as was originally intended. (This proved to be a prudent decision as by spring of the following year, the female was totally blind in her left eye.)
The pair was, ultimately, placed in a 3m x 3m x 2. 7m high glass-fronted,
planted exhibit. The back wall of this exhibit was wire and looked out into the walk-through aviary. The exhibit contained a small pool with running water, a skylight and supplemental fluorescent lighting. After trying several wooden nest boxes and fiberglass simulated logs, in which the pair showed little interest, a natural palm log with a hollow core was installed. The I.Sm tall log was mounted vertically with the base resting on the floor of the exhibit. The hollow core was filled with leaves, pine needles and bark mulch to within one cm of the entrance hole and a perch was attached just below the exterior opening. The top was covered with a removable lid.
Through a slow and tedious process of coaxing, the diet now accepted by the pair consisted of ZuPreem Bird of Prey Diet, avocado, grapes, raisins, soaked dog chow/cat chow mix, bananas, papaya/cantelope mix and tomatoes. Although mealworms and crickets were offered regularly, few were eaten. Chopped pinkies were also fed but seldom touched. Moths and other flying insects were totally ignored. We became concerned that if the quetzals nested, providing the right nestling food would be a difficult problem. Most field observations indicate that chicks are reared on only live foods up to ten days of age. We, therefore, persisted in trying to find other foods that would be accepted, but to no avail.
The pair appeared to adapt well to their exhibit. Their plumage became brighter after each molt and the male's tail feathers lengthened. The two birds, however, were never observed sitting together, allo-preening or otherwise sharing an interest in each other or their nesting site. I still wondered whether the female's body cavity was stuffed with cotton balls or excelsior.
In early April 1985, the male was noticed pulling at fibers around the entrance to the nest log and he gradually began entering and removing materials from the cavity. The female showed no interest in this cavity until July of 1985 when she was also observed pulling at the loose fibers around the nest hole. I was finally convinced after three and a half years that she was actually a real living bird. On 15 August, 1985 the female began entering the log for brief periods while the male perched at the entrance. By 12 September, the female was remaining in the log for longer periods of time. When the nest was opened for inspection, we discovered that all of the material had been removed from the cavity right down to the ground level.
We did not wish to disturb the pair's efforts, but knowing that if eggs were laid and hatched, we would never be able to reach the eggs or chicks due to the depth of the cavity, we debated whether to repack the hollow. On 16 September, the log was refilled. This time the lower half was packed with dried leaves and the top half wth clean pine shavings. The male almost immediately began removing the shavings and by the following day he had excavated to a depth of 20. 3 cm. Thereafter digging slowed. On 26 September, the male was seen dropping a leaf from the hole to the outside which meant he was down to the leaf level. Three days later, both birds were seen removing leaves. Excavation continued until the cavity eventually reached a depth of 45.7 cm below the nest. A keeper's arm could barely reach the nest from the removable top of the log.
References
Delacour, Jean. 1943. Quetzals. Avicultural Magazine, 5th Series. Volume 8, Number 6, 165-168. e