Amazona imperialisimperial amazon(Also: imperial parrot)

Geographic Range

The Imperial Amazon (Imperial Parrot, Sisserou) is endemic to the island of Dominica in the Lesser Antilles. Formerly more widely distributed over the island, it is now confined to Mount Diablotin in northern Dominica, especially the upper Picard River Valley (Devil's Valley) on the northwest side of the mountain.

(Collar, et al 1992, Forshaw 1973)

NOTE: SELECTED TERMS ARE DEFINED IN THE "COMMENTS" SECTION OF THIS NARRATIVE.

Habitat

The Imperial Amazon is a montane species living primarily at elevations from 600 to 1300 meters. Occasional sightings have been made as low as 150 to 300 meters. These parrots dwell in primary rainforest canopy, descending from the canopy only in response to shortages in their normal food supplies (see under "Behavior").

(Collar, et al 1992)

Physical Description

TYPICAL MEASUREMENTS

(in mm unless othewise noted)

Body: 45 cm.

Wing: male 286, female 284.

Tail: male 169, female 166.

Tarsus: male 31, female 32.

Exposed culmen: male 39, female 39.

Eggs: 46 x 39.

GENERAL DESCRIPTION

A stocky bird, typically parrot-like in appearance with a large head, large bill with hooked upper mandible, and a short, square tail. See below for plumage description.

ADULT PLUMAGE

Head feathers, except cheeks and ear coverts dark maroon-purple tipped with black; ear coverts reddish-brown; cheeks brownish-maroon edged with black; breast and abdomen feathers purple with black margins; flank and thigh feathers green with greenish-blue tips; undertail coverts olive-green with greenish-blue tips; mantle, back, rump and uppertail coverts green edged with black; wings green with red carpel edge, dark maroon speculum across bases of outer secondaries, primaries violet-blue with green bases and brown tips, secondaries green becoming violet-blue towards the tips, underwing coverts green with blue tips, undersides of flight feathers green; tail reddish-brown with greenish-blue tips, central feathers and bases of lateral feathers suffused with green; bill greyish-horn; iris yellow to orange-red; legs grey.

IMMATURE PLUMAGE

Occiput, nape and hindneck green; posterior of cheeks greenish; iris brown.

(Forshaw 1973)

Reproduction

Pairs of Imperial Amazons occupy and defend a nesting territory throughout the year, making their presence known with self-advertising display flights. Absences from the territory are more frequent from September through December. The breeding season is February through June, especially March through May. This coincides with the dry season and the season of greatest food abundance, which in turn supports feeding of nestlings and fledglings. Imperial Amazons have been observed nesting in cavities high in the trunks of the dominant forest trees of their habitat, chataignier (Sloanea berteriana) and gommier. In addition, there are unconfirmed reports of nest sites in the tops of dead mountain palm tree trunks.

The reproductive rate of this species is low. A pair may only nest every other year, normally fledging one young from a clutch of two eggs. Age of first breeding is unknown, nor is it known wether nest site availability is a limiting factor.

(Collar, et al 1992)

Behavior

Imperial Amazons are very shy and difficult to approach. They are usually found in pairs or small flocks, sometimes with Red-Necked Amazons (A. arausiaca), also native and endemic to Dominica. They are especially unobtrusive from July to November. They normally feed in the forest canopy, but were observed feeding near ground level on shrubs and vines in 1979 and 1980 (see "hurricanes" in the "conservation" section). Their plumage blends very well with foliage, making them difficult to see when feeding in the treetops. Times of greatest activity are 0600-1000 and 1600-1900. They normally roost in large chataignier or gommier trees, the same trees being used year after year. The calls of the Imperial Amazon are a variety of harsh screeches, trumpeting squawks, shrill whistles and shrieks. As with most parrots, none of its calls are melodic or song-like.

(Forshaw 1973, Collar, et al 1992)

Communication and Perception

Food Habits

Imperial Amazons feed on fuits, seeds, nuts, berries, blossoms and shoots. Especially favored are the fruits and seeds of bois cote (Tapura antillana), gommier (Dacryodes excelsa), kaklin (Clusia venosa), mangle (Symphonia globulifera) and mountain palms (Euterpe dominicana and E. globosa), including the young shoots of these last two. In addition, they feed on the fruits and seeds of balate (Pouteria palladia), bois bande (Richeria grandis), bois blanc (Simarouba amara), bois diable (Licania ternatensis), bois riviere (Chimarrhis cymosa) and carapite (Amanoa caribaea).

(Collar, et al 1992, Forshaw 1973)

Conservation Status

The Imperial Amazon is considered a relict species. Because of its endemism on Dominica and the destruction of its habitat, its range will always be small. This, in combination with its low reproductive rate, means that the Imperial Amazon will always be relatively rare. Due to the species' inherent shyness and very rugged home terrain, population estimates carry a fair degree of uncertainty. A 1990 estimate put the entire population at around eighty birds. The most recent field work (as of 1999) estimates a population of under 200 individuals. Threats to this species' survival are multiple.

HABITAT LOSS

Habitat protection is extremely important to the continued existence of the Imperial Amazon. Adequate habitat is needed to support and rebuild the population, as well as a buffer zone in between the parrots and human activity. Parrot habitat has been extensively logged for valuable timber, charcoal production and conversion to cropland. One estimate states that more forest has been lost on Dominica during the 1980's that in the previous 1000 years. Selective logging is little better than clearcutting, as the trees most needed for the parrots' survival are targeted. Also, logging operations do extensive damage to the remaining vegetation and open up the forests to further human disturbance. In some cases of converting forest to farming, aerial spraying of banana crops has reportedly led to poisoning and blindness in parrots. In some formerly forested areas of Dominica, replanting of dominant native rainforest trees is feasible, especially those areas not converted to agriculture. This would benefit the parrot populations but must be considered part of a long-term strategy, as these trees are slow-growing. As of January 2000 the creation of Morne Diablotin National Park on Dominica will be finalized. This park, first proposed in 1976, is a tremendous step forward in setting aside vital habitat for both of Dominica's endangered parrots.

HURRICANES

While wildlife in the Caribbean has had many millenia to adapt to hurricanes, the weakening of populations through human activity can magnify the effects of natural threats to the point where what would otherwise be a temporary setback can threaten to eliminate entire species. Hurricane David of August 1979 was exceptionally strong, striking directly across Dominica and destroying five million trees in the southern forests alone. Trees that were not felled were stripped of fruit. Even on the most sheltered part of the island, four out of five known Imperial Amazon nest sites were destroyed, with similar effects elsewhere. Parrot populations on the island were reduced by half as a result, and previously viable populations of Imperials on Mount Anglais and Mount Watt were reduced to unviable numbers. The less powerful hurricane Allen struck Dominica in 1980, again stripping fruit off trees. By all accounts, Imperial Amazons failed to breed for two straight years. By 1985 all populations of Imperial Amazons outside of Mount Diablotin had disappeared. At current population levels, another hurricane with the power and trajectory of David could cause the extinction of the Imperial Amazon in the wild.

PREDATION

Possible predators of Imperial Amazons are Boas (Boa constrictor), Broad-Winged Hawks (Buteo platypterus), Opossums (Didelphis marsupialis) and Rats (Rattus sp.). Only Opossums are thought to have any possibility of being a serious threat. They are beleived to have been introduced in the nineteenth century.

COMPETITION

The Pearly-Eyed Thrasher (Margarops fuscatus) is a possible nest-site competitor, but it is apparently too uncommon in the Imperials' range to pose a serious threat. There is no evidence that Imperial and Red-Necked Amazons compete with each other in spite of overlapping ranges. Exotic parrot species kept as pets on Dominica could pose a threat if escapees establish populations. Stricter controls on the importation of exotic parrots may be needed.

HUNTING

Until the early 1980's hunting was the most significant population limiting factor for Imperial Amazons. They were commonly shot for food both by Dominicans and hunters from neighboring Guadelupe, especially in the rainy season when they were fat and excellent eating. Dominican laws restricting parrot hunting were first enacted at least as early as the nineteenth century. By 1914 the hunting of parrots was completely banned. In the wake of Hurricane David a total ban on hunting all wildlife was enacted. Conservation Officers were hired to enforce the ban, which has brought the hunting problem mostly under control. Since about 1981 there has been little evidence of hunting pressure.

TRADE

In the past, live parrots had been collected for the pet trade on Dominica through a practice called "wing shooting." Because of high prices offered for live birds (mostly by residents of the island) and the inaccessibility of nests for collecting young, many locals attempted to wing-shoot the birds, which resulted in the deaths of many parrots. Collecting parrots in any manner for the pet trade is now illegal on Dominica. A compulsory registration program of all captive birds (with amnesty) has closed the market for Imperial Amazons on the island. Smuggling parrots off of the island for the international pet trade does not appear to be a significant threat at this time. However, unscrupulous foreign bird collectors continue attempts to acquire both Amazona species from Dominica.

OTHER ACTIONS BEING TAKEN

Education and awareness initiatives were begun in earnest around 1980 on Dominica. The Dominica Forestry Division conducts school visits, public lectures, radio broadcasts, poster and tee-shirt distribution, circulates a conservation education newsletter and produces a play called "Parrot Poachers."

(Collar, et al 1992, Forshaw 1973, Reillo, pers.comm. 1999)

Other Comments

FOR MORE INFORMATION

For the most up-to-date information on the status of the Imperial Amazon and other endangered species, contact the Rare Species Conservatory Foundation in Loxahatchee, FL at www.rarespecies.org.

DEFINITIONS

cere: unfeathered, thick skin adjoining the forehead at the base of the upper mandible.

CITES: Convention on International Trade in Endangered Species.

coverts: the smaller feathers of the wing or tail that cover the bases of the larger feathers.

endemic: restricted to a given region.

exposed culmen: Length in a straight line from the tip of the upper mandible to the anterior edge of the cere.

montane: a biogeographic zone of relatively moist cool upland slopes below timberline in which large evergreen trees dominate.

nape: the back of the neck, lying between the occiput and back.

occiput: the back of the head, lying between the crown and nape.

relict: an isolated population that appears to be a fragment of a former widely distributed population.

speculum: a metallic or brightly colored patch comprising the upper surface of the secondary flight feathers.

tarsus: the third distal segment of the leg between the crus (shank, drumstick) and the toes, typically covered in scales and feathered only at the upper joint.

(Cox 1996, Woolf 1976)

Contributors

Cynthia Sims Parr (editor), Animal Diversity Web.

Jim Carbone (author), Eastern Michigan University.

Glossary

Neotropical

living in the southern part of the New World. In other words, Central and South America.

World Map

acoustic

uses sound to communicate

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

motile

having the capacity to move from one place to another.

mountains

This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

rainforest

rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

tactile

uses touch to communicate

visual

uses sight to communicate

References

Collar, N., L. Gonzaga, N. Krabbe, A. Madrono Nieto, L. Naranjo. 1992. Threatened Birds of the Americas. Washington, D.C.: Smithsonian Institution Press.

Cox, R. 1996. Birder's Dictionary. Helena, MT: Falcon Press.

Ed. by Woolf, H. 1976. Webster's New Collegiate Dictionary. Springfield, MA: G. & C. Merriam.

Forshaw, J. 1973. Parrots of the World. Neptune, NJ: T.F.H. Publications.