Abstract
Introduction
Toucanets, along with toucans and aracaris, belong to the New World family Ramphastidae, which is comprised of six genera and forty-one species.
As the term implies, the toucanet is a smaller version of the toucan, and may often appear not to be related at all. Certainly the emerald toucanet fits here, for it is one of the smallest of the Ramphistids, whose bill more closely resembles that of a large barbet rather than the flamboyant blade of the more closely related toco toucan - a fellow family member.
Description
The emerald toucanet (A ulachorynchus prasinus) is almost entirely emerald green with the following exceptions: throat light greenish white, tips of tail feathers, underside of tail and vent reddish brown, legs and feet gray, eye ring and iris black, upper mandible of beak predominantly yellow with central portion brown, lower mandible maroon brown
tipped in yellow. Sexes are indistinguishable except for beak length, the female's being shorter.
In captivity the emerald green color fades to a bluish green unless the birds are color fed with a carotinoid base food additive as is commonly done with flamingoes, scarlet ibis and red factor canaries.
Range
The Emerald toucanet has a limited distribution as Ramphastids go. It ranges from southeastern Mexico (state of Vera Cruz) to northern Nicaragua. It inhabits the humid mountain forests of the highlands and locally the wooded foothills. When not breeding the emerald is found in small flocks in the forest canopy foraging for fruit and berries. They nest in hollow trees during March to April laying two white eggs.
Captive Environment
A large 16' x 16' x 9' flight was prepared as a potential breeding facility for one pair
of emerald toucanets. The rear wall of the flight as well as the adjoining four feet of both walls and roof were constructed of plywood, forming a solid shelter against wind and rain. The remainder oft he flight walls and roof were constructed of Y2" x 1/2" mesh welded wire stretched over frames of redwood 2 x 4's. The flight was completely open on the inside allowing unlimited access between shelter and screen area. No other heat or weather precautions were taken.
ln the open portion of the flight in one corner a multi-forked branch was hung, which became the night roost for the pair. In the shelter a perch of ·Yi" dowel was suspended six feet from the ground.
In one corner of the shelter a six foot long palm log of undetermined species was erected. This log had previously been hollowed out to a depth of two to three feet and was donated by Dale Thompson in 1977. It had previously housed woodpeckers and crimson-rumped toucanets.
Near the opposite side of the shelter, away from the nest log a feeding station was provided. This station consisted of a platform two feet from the ground and was secured to a small post. By placing a mild insecticide such as Malathion dust around the post, ants were deterred from dining on the fruit offered the toucanets.
The flight was devoid of any vegetation except for bermuda grass and spontaneous weeds growing on the ground. Subsequent experiences with planted flights for Ramphastids has taught that they will playfully pluck all leaves off whatever plants are provided, unless the plants are hardy, fast growing, outnumber the birds significantly, and the birds weary of the pastime.
Breeding
Into the above flight was placed a single pair of emerald toucanets obtained in 1976. In the spring of 1977 the birds twice attempted to rear young, but were unsuccessful as reported in a previous issue of Watch bird.
In early May 1978 the pair was once again observed actively excavating the log nesting cavity. By mid-May the birds were incubating eggs, though they would usually leave the nest at the sound of approaching visitors. The hen did most of the
incubation and brooding of the young.
On May 27, 1978 the faint sounds of young nestlings could be heard. Since it is not exactly known when incubation began, no definite incubation period was determined, however, it is somewhere between two to three weeks.
On June 15th nestling sounds ceased.
An inspection of the nest was made by laying the log on the ground and gently tilting the bottom skyward until the contents rolled to the entrance hole (the only access to the log). Two babies appeared alive and well. Both young had developed pinfeathers, though one was significantly larger than the other.
On July 2, 1978 the first youngster appeared at the nest entrance, but did not fledge until July 3rd. Once the first youngster left the nest, the second youngster appeared at the nest entrance, fledging the following day.
During the first few days out of the nest, the young toucanets were very flighty and uncoordinated. At the slightest disturbance they would fly into the wire through which their beaks would protrude, causing beak damage and ultimately breaking off the beak tips in both birds. These tips, fortunately, regrew and resumed their normal appearance within six months. It was nearly a month after fledging before the clumsy, panic flying behavior ceased.