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Puerto Rican Amazon (Amazona vittata) - Wiki
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Puerto Rican Amazon
From Wikipedia, the free encyclopedia
[Photo] Puerto Rican Amazons (Amazona vittata). Created by the U.S. Fish and Wildlife Service.
The Puerto Rican Amazon (Amazona vittata), also known as the Puerto Rican Parrot, is an endemic parrot of the archipelago of Puerto Rico belonging to the Amazona genus of the Psittacidae family. Another common name for the Puerto Rican Amazon is Iguaca, an onomatopoeic name given by Ta??nos that resembled the sound the parrots make when they take flight.
Measuring 28 to 30 cm (11-12 in) in size, the Puerto Rican Amazon is predominantly green in color with a red forehead and white rings around the eyes. It is small for an Amazon parrot.
Initially widespread and abundant, the Puerto Rican Amazon declined drastically in the 19th and early 20th centuries with the removal of most of its native habitat. The species is the only remaining native parrot in Puerto Rico and one of the ten most endangered bird species in the world. Conservation efforts were started in 1968 to save this species from likely extinction. As of 2006 the total wild population is estimated at 44 individuals.
Taxonomy and naming
The Puerto Rican Amazon was described by Dutch ornithologist Pieter Boddaert in 1783. It belongs to the large neotropical genus Amazona, commonly known as Amazons; these birds have also been given the generic epithet of 'parrot' by the AOU, hence Puerto Rican Parrot is an alternative common name. The Ta??no people have called it the Iguaca after its call.
It has been divided into two subspecies:
A. v. vittata is the nominate and only extant subspecies, inhabiting Puerto Rico and formerly nearby Vieques Island.
A. v. gracilipes inhabited Culebra Island and is unclear whether it was distinct.
Description
The Puerto Rican Amazon has green feathers with blue edges, a red forehead and white ovals around the eyes. The underside of its feathers have a slightly different hue with the wings' underside feathers, which can be seen during flight, being brightly blue and the tail's being yellow-green. Sexual dimorphism is not present in this species. Aside from invasive DNA-sexing sexes can only be distinguished by behavioral differences during the breeding season. Puerto Rican Amazons measure from 28 to 30 cm (11???12 in) and weigh from 250???300 g (9???10.5 oz) with an average of 275 g (10 oz). The Puerto Rican Parrot, compared to other Amazona species, is small but is of a similar size to other Amazona species of the Greater Antilles. Its closest relatives are believed to be the Jamaican Black-billed Amazon (Amazona agilis) and the Hispaniolan Amazon (Amazona ventralis).
Population and distribution
At the time of Columbus's arrival to Puerto Rico in 1493 the Puerto Rican Amazon was widespread and abundant. Evidence suggests that it may have also inhabited the island of Antigua and the Virgin Islands. During the latter half of the 19th century most of Puerto Rico's virgin forests, historical habitat of the species, were cleared to allow for agricultural development, primarily for sugar production. In the early 20th century the species was extirpated from Puerto Rico's smaller islands???-Culebra (1912), Vieques and Mona???-and became restricted to five locations: two in karst-limestone areas, two in high montane rain forests and one in mangrove forest at the foot of the Caribbean National Forest. By 1940 the species was restricted to primary forest at the Luquillo Mountains in the Caribbean National Forest.
Historically the species occurred in eight mature or old-growth forests in Puerto Rico at all elevations and in holes in cliffs and other diverse habitats at lower elevations. The species could be found at medium elevations at the Guajataca State Forest until 1910 and in the Rio Abajo State Forest until the 1920s and at high elevations in the Carite State Forest until the 1930s. The present elevation for the species is between 396 and 823 meters (1,300 and 2,700 feet). Since the species needs mature forests with open-cavity trees for reproduction, dwarf and second growth forests are not inhabited. The current range of the species is 16 km², 0.2% of its former range.
Early population estimates vary greatly with some authorities claiming more than one million individuals while others propose a more modest amount of 100,000 individuals. During the first 150 years of Spanish rule the human population was small. In 1650, when the population of the island was 880 people, the species was still abundant throughout the archipelago. After 1650 the human population increased exponentially, and the Puerto Rican Parrot population started to decline. Heinrich Moritz Gaede, a German naturalist, declared that by 1836 the parrot population had noticeably declined. In the 1950s the population declined to 200 individuals. This trend continued, reaching an absolute low of 13 individuals in 1975. A short-lived recovery followed and in August 1989 the population was estimated at a minimum of 47 individuals. However, on September 18, 1989, Hurricane Hugo struck the northeast coast of Puerto Rico inflicting heavy casualties on the remaining individuals. In the aftermath of the hurricane the population was estimated at 23 individuals. Presently, the population is estimated at 44 individuals.
Behavior
Like other Amazons, the Puerto Rican Amazon is gregarious, and territorial around its nest.
Diet
Like almost all parrots, the Puerto Rican Amazon is a herbivore. Its diet consists of flowers, fruits, leaves, bark and nectar obtained from the forest's canopy. Presently, the species has been recorded to consume more than 60 different materials. Historically, because it had a larger range, its diet was more varied. Among the items it presently consumes are the pericarp of the seeds of sierra palm (Prestoea montana), tabonuco (Dacrycodes excelsa), and negra lora (Matayba domingensis); the fruits of bejuco de rana (Marcgravia sintenisii), camasey (Miconia sintenisii), cupey de altura (Clusia gundlachii), and palo de cruz (Rheedia portoricensis); the flowers of bejuco de rana, achiotillo (Alchornea latifolia), and Piptocarpha tetrantha; the leaves and twigs of cupeillo (Clusia grisebachiana), laurel sabino (Magnolia splendens), caimitillo verde (Micropholis garciniaefolia), and Piptocarpha tetrantha; the bark of bejuco de rana, cupeillo, and cachimbo cumun (Psychotria berteriana); and the buds of cuaba (Inga vera).
Reproduction
Puerto Rican Amazons are secondary cavity nesters; they nest in tree trunk cavities that cannot be made by themselves. The species mainly nests in palo colorado trees (Cyrilla racemiflora) with other trees, such as the laurel sabino (Magnolia splendens) and tabonuco (Dacryodes excelsa) used to a lesser extent. These trees are mature cavity forming trees which provide protection against predators and the entry of water. Recently, the species also nests in artificial wooden boxes designed as part of the recovery plan for the species. Nest height varies from 7 to 15 meters above ground. Males usually lead the search for nest sites and once a site is selected, the pair spend some time inspecting and cleaning it. No lining material is added to the nest.
Puerto Rican Amazons reach sexual maturity at 4 years of age in the wild and at 3 years in captivity. The species usually mates for life and normally reproduces once a year during the dry season, between the months of January and July. The female lays 2???4 eggs that she incubates exclusively for a period of 24 to 28 days. The chicks are fed by both parents until they leave the nest around 60 to 65 days after they hatch. Nonetheless, they remain dependent on their parents and travel with them until the next breeding season.
Threats and conservation efforts
The Puerto Rican Amazon is one of the ten most endangered bird species in the world. It entered the United States Endangered Species list on March 11, 1967, and in 1968 recovery efforts began to increase the population in the wild. In 1972, when the estimated population was 16 individuals, the United States Fish and Wildlife Service at the Luquillo Aviary began efforts to breed parrots in captivity. Conservation efforts have paid off remarkably. In June 2006 it was reported by the USFWS that its birds in captivity had successfully hatched 39 chicks (the yearly average is around 16). Presently, the total wild population is estimated at 44 individuals.
Threats
Arguably the main reason for the population decline of the Puerto Rican Amazon is man. Early settlers of Puerto Rico, such as the Ta??no, hunted it for food consumption but managed to maintain a healthy ecological balance. More recently, habitat destruction, capture of immature individuals for the pet industry, hunting, and predation have contributed to the sharp population decline. It is believed that the main reason for the decline of population is the clearing of mature forests for agricultural development.
Natural predators of the Puerto Rican Amazon include the Red-tailed Hawk (Buteo jamaicensis), the Broad-winged Hawk (Buteo platypterus), the Peregrine Falcon (Falco peregrinus) and the Pearly-eyed Thrasher (Margarops fuscatus). The thrasher has invaded Puerto Rico in the mid-20th century and become a problem for the parrots since 1973; to combat this, specially designed deep nests were prepared for the parrots in subsequent years to prevent competition from the invaders.
Competition from introduced honeybees (Apis melifera) for nesting cavities also represent a threat to the species. Introduced Black rats (Rattus rattus) and mongooses (Herpestes javanicus) may eat eggs and chicks and may also compete for nesting cavities.
Natural disasters, such as hurricanes, were not historically a threat to the Puerto Rican Parrot population, however, as a result of the fragmentation and reduction of the population these disasters are a threat to the species. In September 1989 Hurricane Hugo passed through the species's current range and reduced the population from 47 to 23 individuals.
Recovery plan
Due to the low population and endangered status of the Puerto Rican Amazon a recovery plan was drafted and implemented in 1968. Its main objective was to downlist the species to threatened status by the year 2020. Other objectives included the establishment of two separate, effective, wild populations (500 or more individuals for 5 years), the protection of habitat for those populations and the control of predators, parasites and competitors of the species.
In 1973, as part of the conservation efforts, a captive population was established in the Luquillo Aviary. Another captive population was established in 1993 when some individuals where transferred from the Luquillo Aviary to the Rio Abajo State Forest under the administration of the Puerto Rican Department of Natural Resources (Departamento de Recursos Naturales).
http://en.wikipedia.org/wiki/Puerto_Rican_Amazon
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