- Order: Trogoniformes
- Family: Trogonidae
- Polytypic 2 Subspecies
The Resplendent Quetzal primarily is frugivorous, although it occasionally take insects or lizards, especially to feed young. The Resplendent Quetzal forages in the midstory of the forest (Stotz et al. 1996). Wheelwright (1983) found the costaricensis subspecies in Monteverde, Costa Rica feeds on fruits of 41-43 plant species in 17 families. Nearly half of these species were part of the Lauraceae family. The mocinno subspecies in Chiapas, Mexico forages on 32 species of plants (Solorzano et al. 2000). Avila et al. (1996) and Wheelwright (1983) found over half of the total number of fruit items in the quetzal's diet were from Lauraceae.
The Resplendant Quetzal forages primarily by sallying for fruit, plucking it from trees on the wing. Quetzals also occasionally sally for fruits from understory shrubs or pursue lizards on the ground (Wheelwright 1983). Its large flight muscles - 21% of the total body mass- reflect its primarily aerial foraging mode (Wheelwright 1983). Additionally, the quetzal's digestive track has unique adaptations presumably associated with eating fruit with large seeds. Wheelwright (1983) found the esophagus to have a thin wall, elasticity, and rings of circular muscles, likely to aid in the regurgitation of large seeds. Quetzals lack a crop, and the intestine and caecal sacs often are full of fruit skins, probably indicating bacterial digestion (Wheelwright 1983). The flexible mandible and clavicle of the bird enable it to swallow wider fruit than predicted based on the gape.
The Resplendent Quetzal has been described as wary and cautious by Bowes and Allen (1969), who found it to sit motionless for long periods of time and orient itself so the bright red on the underside would not be visible to an intruder. It will turn its head from side to side, looking in each direction for 1-3 minutes.
Skutch (1944) observed male quetzals to commonly take flight by dropping backward off a branch. LaBastille et al. (1972) reported this behavior in both males and females.
Preening was noted on occasion by LaBastille et al. (1972), and it was described as pecking under and around the wings and breast. They once noted a female leave the nest hole, preen for five minutes, and then return to the hole.
The average territory defended by a quetzal includes a 305 m radius around the nest tree (Bowes and Allen 1969). Bowes and Allen (1969) estimated the average home range to be 15 to 25 acres per pair.
Bowes and Allen (1969) observed a female quetzal attack a stuffed quetzal placed outside her nest hole. Wheelwright (1983) observed both sexes chase off Emerald Toucanets (Aulacorhynchus prasinus).
During spring the male performs flight displays, flying above the canopy and then ascending while vocalizing (Skutch 1944). Wheelwright (1983) observed that some pairs had formed before returning to the breeding area in higher elevations of Costa Rica while some birds still were unpaired. Among the unpaired birds, Wheelwright (1983) observed up to four males simultaneously chasing females. LaBastille et al. (1972) also witnessed courtship chasing while vocalizing. Copulation is believed to occur in association with the pair's shared nest building activities (Wheelwright 1983).
Social and interspecific behavior
The species generally is solitary; Bowes and Allen (1969) never saw more than three together. Occasionally may aggregate at food sources. Wheelwright counted up to 20 individuals in a heavily fruited tree during the breeding season.
While Wheelwright (1983) indicated nest failure to be high (67-78%) and likely primarily from the long-tailed weasel (Mustela frenata), he also noted defense against squirrels and Emerald Toucanets (Aulacorhynchus prasinus). He suggested that snakes, botflies, and larger animals also may predate the nests. In contrast, he believed the predation on adults to be limited and reported only two cases of predation on an adult: one by an unidentified hawk and one brooding adult taken by a margay (Leopardus wiedii). Bowes and Allen (1969) suggested the quetzal predators may include red-bellied squirrel (Sciurus aureogaster), kinkajou (Potus flavus), and the Ornate Hawk-Eagle (Spizaetus ornatus), as well as other hawks and owls.
Solorzano et al. (2000) found that the primary reproductive activities occur when fruits are most abundant. Similarly Wheelwright (1983) noted that breeding in Costa Rica corresponded with the peak of fruiting of Lauraceae trees. Thus, the breeding season falls between March and June, depending on location (Johnsgard 2000). Nesting is delayed in poor fruit years (Wheelwright 1983).
Nests are cavities, excavated in dead trees or stumps by the male and female. They appear like that of a large woodpecker (Skutch 1944). Wheelwright (1983) found the average height in Costa Rica to be 8.8 m in a limb or trunk of a tree. Bowes and Allen (1969) found the average nest height in Guatemala to be 9.5 m. If the same snag was used in a successive year the height of the cavity was lowered to accommodate decay (Wheelwright 1983). Nest cavities generally measure 10 cm at the entrance, with the nest 20 cm back, and a total depth of 30 cm (Bowes and Allen 1969). One pair began excavating five sites in a month before finally selecting one (Wheelwright 1983). Wheelwright (1983) found 43 nest sites in Costa Rica: 74% in forest, 12% in forest or pasture edge, and 14% in snags in the open.
The clutch size of the Resplendent Quetzal is two eggs (Skutch 1944, LaBastille et al. 1972). The few reported single clutch nests may represent incomplete clutches (Johnsgard 2000). Eggs are light blue and subelliptical with a mean of 38.9 mm x 32.4 mm (LaBastille et al. 1972). Nests are not lined, and eggs rest on loose fragments at the bottom of the cavity (Skutch 1944).
In addition to nest building, the male and female share in incubation. Skutch (1944) observed one nest that was incubated for 17-18 days, while Wheelwright (1983) observed two nests that were incubated for 18-19 days. Skutch (1944) and LaBastille et al. (1972) both observed double shifts with the female incubating over the night and the middle of the day and the male incubating in the morning and evening. In total the male sits six to seven hours each day (Skutch 1944). No nest exchange ritual is employed (LaBastille et al. 1972).
Like other young trogons, Resplendent Quetzal young are born with no down and tightly closed eyes (Skutch 1944). At two days they begin to have pin feathers, and at seven days the contour feathers are breaking from their sheaths. At eight days their eyes open. At ten days the flight feathers (remiges and rectrices) pushed out from the sheaths. On their fourteenth day the young quetzals were well-covered in feathers. At eighteen days green feathers are apparent.
Both parents are involved in provisioning of the young. Initially they spent long periods brooding with infrequent provision of food; later they alternated bringing food every hour (LaBastille et al. 1972). Among the trogons, the Resplendent Quetzal has the best studied nestling diet (Collar 2001). Wheelwright (1983) observed that the male brought more food items than the female and more were insects. The female brought more fruits. Wheelwright also observed shorter return times for parents providing fruits than animal items. Yet, even late in the nestling period, over half of the items give to the nestling were insects or lizards. At one nest, Skutch (1944) found that at sixteen days the mother stopped brooding her chicks in the night and began feeding them less. In the last 5-6 days, the entire duty of feeding the young was left to the male. Chicks fledged at one disturbed nest at 23 days and at 29 days at two others (Skutch 1944).
Resplendent Quetzals raise two clutches each year (Skutch 1944, Bowes and Allen 1969, Wheelwright 1983). Wheelwright (1983) indicated nest failure to be high (67-78%), but there is no information about brood parasitism. All three nests studied by LaBastille et al. (1972) and the two studied by Bowes and Allen (1969) failed. For more information on nest predation, see Predation.
Populations and Demography
The population estimate for the Resplendent Quetzal is 20,000 to 49,999 (BirdLife International 2009); yet, monitoring is called for to produce an up-to-date population estimate.
There is no information related to topics such as age at first breeding, life span and survivorship, dispersal, or population regulation.
Dayer, Ashley A.. 2010. Resplendent Quetzal (Pharomachrus mocinno), Neotropical Birds Online (T. S. Schulenberg, Editor). Ithaca: Cornell Lab of Ornithology; retrieved from Neotropical Birds Online: http://neotropical.birds.cornell.edu/portal/species/overview?p_p_spp=284856