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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)
Other Physical Features: endothermic ; bilateral symmetry
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)
Terrestrial Biomes: rainforest ; mountains
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.
Biogeographic Regions: neotropical (Native )
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)
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)
Perception Channels: visual ; tactile ; acoustic ; chemical
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)
CITES: appendix i
IUCN Red List of Threatened Species: endangered
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)
Key Reproductive Features: iteroparous ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; oviparous
The imperial amazon (Amazona imperialis) or Dominican amazon, also known as the sisserou or sisserou parrot, is a parrot found only on the Caribbean island of Dominica.[3] It has been designated as the national bird of Dominica.[4] The species is critically endangered. In 2019, it was estimated there were only about 50 mature individuals left in the wild.
The imperial amazon measures an average of 48 cm (19 in) in length.[5] With males weighing an average of 900 g (32 oz) and females 650 g (23 oz), the species is large for its genus.[5]
Being of the family Psittacidae, the sisserou has zygodactyl feet and a thick, hooked bill with a muscular tongue.[6] This bill is fashioned in such a way that, using its hinged mandibles and tongue, the sisserou can easily move food around in its mouth.[6]
Males and females have identical plumage: the chest is a dark shade of purple, and the upper parts and feathers are a dark shade of green, with black-edged feather tips.[5] The eye-ring is dark brown, with the eye being a mix of orange and red.[5] Juvenile appearance does not differ much, with a higher occurrence of green plumage and strictly brown eyes.[5]
The call of the sisserou resides in the higher frequencies, a loud and even "squeaky" mix between shriek, squawk, and trill.[5] They are shy, difficult to approach, and usually travel in groups of three or fewer.[5][7] They sometimes flock together with red-necked amazons.[7] They are good climbers and strong flyers with powerful wings.[8] They prefer to perch on the tops of trees.[8] They are difficult to detect, as they are well camouflaged by their plumage.[3]
Between February and April, nesting occurs and the female will lay a clutch of two white eggs in a deep cavity inside a rainforest tree,[5] returning to the same tree year after year. For 26–28 days, the female will incubate the eggs.[5] During fledging, which occurs between June and early September, both parents will take care of and feed the chicks until they are fully feathered and ready to leave the nest.[5] The chicks use typical "begging calls" when hungry, to which either parent will respond with food.[9] Usually only one chick survives to fledging and, typically, sisserou pairs fledge a single chick every other year; however, there have been documented exceptions.[9]
These parrots mate for life and are extremely faithful to each other.[8] They might seek another mate only after a mate dies. However, the bird may grieve to death rather than find a new mate.[8]
The sisserou's diet consists of fruits, seeds, nuts, berries, blossoms and palm shoots.[3] Their favorite foods include the fruits of Dacryodes species, Licania ternatensis, Richeria grandis, Amanoa carboea, Simarouba amara, Symphonia globulifera, Pouteria pollida, Tapuru atillan, the flowers and seeds of Chimarcis cymosa, and the nuts and young shoots of Euterpe palms.[10] Usually, they feed in the morning and evening.[10]
The imperial amazon is endemic to the Caribbean island nation of Dominica in the Lesser Antilles where it inhabits mountain forest areas above 2,100 ft (625 m).[8] It is the island's national bird[11] and also appears on the country's flag.[12] The species frequently occurs in the Morne Diablotins in northern Dominica, especially the upper Picard River Valley on the northwest side of the mountain.[7] A small population has been reintroduced in the Morne Trois Pitons National Park.[13]
Imperial amazons are found primarily in mountain rainforest, sometimes in elfin forest.[10] They occur mostly at elevations of 600–1300 m above sea level.[7] However, there have been reports of them at 150 to 300 meters in elevation because of food storage or foraging preferences.[10]
The imperial amazon is a critically endangered species. There are estimated to be only about 50 mature individuals left in the wild as of 2019.[14] There have been many efforts to help the habitat for these parrots. With the help of Dominica's Forestry, and the Wildlife and Parks Division and the Rare Species Conservatory Foundation (RSCF), areas such as the Northern Forest Reserve and the Central Forest Reserve are protected.[15] However areas adjacent to the Northern Forest Reserve and the Central Forest Reserve remain unprotected.[15] Efforts are being made to help make other areas of Dominica protected. Many of the organizations have helped create groups of people to raise awareness, provide education, and conduct research.[16] The educational programs held in Dominica have reduced the bird trade.[16] The first successful breeding of this species by humans was conducted in 2011.[15] The captive-bred parrot developed fully in 12 weeks and resembled the wild imperial amazon parrots.[17] No one really knew what the reproductive potential of these parrots was. The imperial amazon has the lowest reproductive potential of any of the Amazona species.[17]
A major cause of population decline has been hurricanes. Hurricane David of August 1979 was one of the strongest that hit Dominica and impacted the population. Another hit was by Hurricane Maria in September 2017, which caused extensive damage on the island, affecting habitat.[18]
Habitat loss is caused by human disturbance in the forest, with selective logging and the deforestation. Trapping for food and trade is still a threat, even though education programmes have reduced the local market greatly. Illegal animal trading is a big market, and these birds are hunted to be sold on the black market. In the 1900s there were efforts to ban all illegal bird captivity and trading, but foreign traders still try to hunt this bird; some are successful. The development of plantations has also reduced their habitat, especially the cultivation of bananas (Snyder et al. 2000). Encroachment of human development has been a big issue as well, and conservationists are trying save the birds' preferred habitat.[19]
Nesting cavity competition with red-necked amazons and owls creates a tough living environment for imperial amazons. They mate only for a couple of months of the year, and guard their nests the rest of the year. A good quality nesting site is key to the survival and upbringing of their offspring.
Imperial amazons are preyed on by boa constrictors, broad-winged hawks, common opossums and rats.
The hypothetical or extinct Guadeloupe amazon (A. violacea) may be the same bird as the imperial amazon, if not a close relative. Based on old descriptions alone, the information on the Guadeloupe amazon, pairs well with what is observed about the imperial amazon. A bone found on Marie-Galante (between Dominica and Guadeloupe) has been assigned to A. violacea and suggests that A. imperialis either inhabited, or was traded between, all three islands in prehistoric times.[20]
{{cite web}}: CS1 maint: url-status (link) The imperial amazon (Amazona imperialis) or Dominican amazon, also known as the sisserou or sisserou parrot, is a parrot found only on the Caribbean island of Dominica. It has been designated as the national bird of Dominica. The species is critically endangered. In 2019, it was estimated there were only about 50 mature individuals left in the wild.
