Abstract
It appeared to be an easy climb as the old decayed Quamwood tree (Schizolobium parahybum), situated in the Chiquibul Forest Reserve in the Central American country of Belize, was a mere forty feet tall and without branches. Soon, however, I would realize that a far greater hinderance to climbing would be encountered. As l completed the final adjustments on my tree climbers I could hear the screaming of distant scarlet macaws. Only red specks in the sky, these large parrots were flying from their roosting area to· feed in the interior of the tropical deciduous forest. This old tree, for a softwood, was very firm, making the climb to the top a rather easy task. Half way up the tree, however, I felt a sharp pain in my right leg and upon glancing down discovered that I was slowly being covered with large biting black ants. Despite the annoying pain caused by the ants, I was determined to complete my objective of documenting the growth and development of the white-crowned parrot, (Pionus senilis). With the nest cavity now at waist level I carefully reached in, remembering the local belief that snakes den up in tree cavities during the day, and removed three young parrots. Covered only with pinfeathers, they would be placed in a cotton sack and lowered to the ground. After being weighed and photographed they were hoisted back up the tree and reunited with their cavity. The entire process may have taken only five minutes, but being covered with the angered ants made it seem like hours. This sequence was repeated at this site, and several others, countless times throughout the breeding season.
This parrot was not the only avian species to realize the protection that these insects so freely provided. In every study tree (all were Quamwood) another cavity, usually within several feet from the parrots', was being occupied. The tree most frequently observed was also the home of a pair of ferruginous pygmy-owls (Glaucidium brasilianum). Only 6Yz inches in length, the silent residents of the Quamwood appeared to view my research as a bit disturbing, but not worth getting worked up about. During the final weeks of the investigations they would simply tilt their heads downward and view my climbing about. Never flying off, they soon lost interest with the whole event. Within a few minutes, they would retract their bodies back into the cavity. Only one attempt was made to observe the development of the young owls. And only one small white egg was discovered at the bottom of a very deep cavity. Since my ground crew frequently shouted that the tree appeared to be breaking loose, I decided to give up further attempts.
The ants never harmed the young parrots or the adult owls, but were driven into an uncontrollable rage by the appalling impact of my tree spikes as they pierced the tree. Only seconds after I began my ascent, a black stream of ants would flow down the tree to greet me. Arriving on the ground after such a reception meant rapidly changing clothes.
The smallest of the seven species in the .genus Pionus, the whitecrowned parrot ranges from southern Mexico along the caribbean slope to Panama. Also called the white-capped parrot, it is found in a variety of habitats ranging from lowland rainforest and savannah woodlands to semi-open areas. Its plumage is green with purplish-blue on the wings and tail. A small patch of red is found on the undertail feathers. Its most frequently relied upon field mark is the white on the forehead, forecrown, and chin up to the middle of the throat. The sexes are...