Justification of Red List Category
Once numbering only 13 birds in the wild, this parrot has been saved from extinction. Conservation action has increased the population since 1975, but it remains Critically Endangered because the number of mature individuals remains tiny. Hurricanes Irma and Maria had significant detrimental impacts on the ongoing population recovery and trends are currently uncertain. If the remaining population and future released birds continue to breed in the wild and numbers remain stable or increase, the species may warrant downlisting in the future.
As of 2011, the population numbered c.50-70 individuals spread over two areas, roughly equivalent to 33-47 mature individuals. In 2013, this had increased to c.80-100 individuals in the wild (64-84 at Río Abajo and 15-20 at El Yunque). However, following Hurricanes Irma and Maria in 2017 large areas of habitat were destroyed and the impact on the species's population remains uncertain. The population at El Yunque has not yet been found in its former range, and 17 out of 22 individuals that had recently been released with transmitters have been found dead (Paravisini-Gebert 2018); there are not currently believed to be any birds in the wild in this region. The Río Abajo population has fared much better and persisted successfully despite the hurricanes' impacts, comprising 126-139 individuals by the end of 2019 (M. Lopez-Flores in litt. 2019). The entire Río Abajo population however is derived from released birds, which are not counted as mature individuals until they have bred successfully in the wild (IUCN 2011). Successful breeding has been recorded, including post-Hurricane Maria (Gilardi 2018), and the size and range of the flock has been witnessed to be increasing however, due to the late age of first breeding in this species, it is likely that the majority of the population still comprises introduced individuals (Breining 2009; Valentin 2009; T. White in litt. 2012). As a result, the total number of mature individuals remains uncertain and is tentatively assumed to remain below 50 due to the large proportion of reintroduced individuals and severe impacts of Hurricanes Irma and Maria.
An increase of 1-19% was estimated to have occurred over the last ten years, based on regular counts of the total wild population, largely as the result of successful reintroductions from the Iguaca and Río Abajo aviaries (M. Lopez-Flores in litt. 2019). However, following the impacts of Hurricanes Irma and Maria that hit the island in 2017, the population in El Yunque is considered to have been lost (Paravisini-Gebert 2018) whilst contrastingly, the population in Río Abajo persists and is likely increasing (Milpacher 2017; M. Lopez-Flores in litt. 2019). The overall impact of these hurricanes, and concurrent ongoing reintroductions, therefore remains uncertain and the population trend is considered unclear.
This species is endemic to Puerto Rico (to U.S.A.), and once occurred throughout the forested parts of the island. An endemic subspecies gracilipes occurred on Culebra, but became extinct in 1912. Once abundant, there has been a drastic decline, which reduced the population to c.2,000 by the 1930s and an all-time low of 13 birds in 1975. It has been confined to the Luquillo Mts (El Yunque National Forest) since the 1960s, and the present occupied range of 16 km2 represents only 0.2% of its former distribution (Snyder et al. 1987). Conservation action has prevented the species's extinction, although recovery has been slow and the population remains tiny. In 1989, Hurricane Hugo cut the wild population from 47 to about 23. By the beginning of 1992, there were a minimum of 22-23 parrots in the wild and 58 in captivity, with a record fledging success in July 1992 taking the wild total to 39 or 40 individuals. In 2000, the population numbered 40 wild birds, plus 10 recently re-introduced birds and 100 in captivity, held in two aviaries (Davis 2000; T. White in litt. 2012). In 2001, thieves broke into an aviary and stole a number of captive adults. In 2004, the wild population numbered 30-35 individuals (Arendt 2000). In 2006, 20 birds were released in the Río Abajo State Forest marking the beginning of a second population in the wild (Velez-Valentin and Boyd 2006). A further 26 birds were released here in December 2007 and 19 more in December 2008, with the first two successful nests recorded in the wild at Río Abajo in 2008 (T. White in litt. 2005, 2008, 2012). As of 2011, the population numbered c.50-70 wild individuals spread over two areas, and about 280 captive individuals (Breining 2009; T. White in litt. 2012). In 2013, there were 64-84 adults and 16 chicks at Río Abajo and a further 15-20 individuals at El Yunque. In that year, the first natural nest in 42 years was recorded in Río Abajo (V. Anadon in litt. 2013; Coto 2013). 400 individuals were recorded in captivity in 2013 (Coto 2013), including a record 107 chicks produced in captivity (Anon. 2013a). In the same year, at least three captive-bred birds were released in the Río Abajo Forest and were subsequently found to be flocking with approximately 150 Orange-winged Amazons Amazona amazonica away from the original release site (Anon. 2013b). In May 2014, two young birds were discovered in a natural nesting hole outside the boundary of a national park (Anon. 2014b). The impacts of Hurricanes Irma and Maria, which hit the island in 2017, on the species are not yet fully known, but the population at El Yunque is no longer known from its natural range and it is considered that there are no longer any wild individuals in the region; 300 individuals persist within the Iguaca aviary however (Paravisini-Gebert 2018; M. Lopez-Flores in litt. 2019). The population at Río Abajo however, persists and alongside the 212 individuals held within the aviary, a population of 126-139 wild individuals are thought to be inhabit the region's forests (Milpacher 2017; M. Lopez-Flores in litt. 2019).
Historically, the species occurred in montane and lowland forest and mangroves. It is now restricted to forest at elevations of 200-600 m. It breeds between late February and July, when it nests in large, deep tree-cavities and lays 3-4 eggs (Raffaele et al. 1998; Arendt 2000). Since 2001, all known nesting in the wild has occurred in artificial cavities (White et al. 2006) until in 2013, the first natural nest in 42 years was recorded in Río Abajo (V. Anadon in litt. 2013; Coto 2013).
Suitable forested habitat for this species has almost entirely been lost. Hunting for food, pest control and the cage-bird trade have had crippling effects in the past (T. White in litt. 2012). The principal threats are now competition for nest-sites, loss of young to parasitic botflies, predation and natural disasters such as hurricanes (Raffaele et al. 1998; Arendt 2000). Red-tailed Hawks Buteo jamaicensis predate parrots and hamper releases of captive-bred individuals. Predator-aversion training prior to release has improved the survival of captive-reared birds after release into the wild (White et al. 2005); nevertheless raptor predation claimed 21% of all released individuals between 2000 and 2002 and is considered to have removed one of the two remaining individuals from the now absent El Yunque National Park population (M. Lopez-Flores in litt. 2019). The species formerly suffered from competition for nesting cavities with Pearly-eyed Thrasher Margarops fuscatus, but this has been significantly reduced by specially designed artificial nesting cavities (T. White in litt. 2012). Predation by alien invasive mammals is also having a serious impact upon productivity, with six fledglings taken by Small Indian Mongooses Herpestes auropunctatus and one nest failure from Black Rats Rattus rattus during 2000-2003 (Engeman et al. 2006); the Luquillo Forest of El Yunque has the amongst the highest Black Rat densities of any site studied globally (J. Thompson in litt. 2019). Although predation events have not been documented, feral cats Felis catus, which are well-documented around the world as devastating bird predators, are also common in parrot habitat in El Yunque National Forest, and represent another threat from an invasive mammal. Parrots regularly disappear without identification of a cause, while cats and mongooses are capable of inflicting unidentifiable losses (R. M. Engeman in litt. 2012). The Puerto Rican Boa comprises an additional potential nest predator (J. Thompson in litt. 2019). It has been suggested that hurricanes are the most serious limiting factor preventing population recovery, and climate change may cause the frequency of hurricane events to increase. Such devastating hurricane impacts are apparent in the aftermath of Hurricanes Irma and Maria with the wild population of Amazona vittata no longer present in El Yunque (M. Lopez-Flores in litt. 2019). Furthermore, rainfall hampers the recovery programme, as chicks that fledge either during or before a major rainfall event have a much higher mortality rate than chicks that fledge during drier periods (Breining 2009).
Conservation Actions Underway
CITES Appendix I. A recovery programme for the species has involved a partnership between the U.S. Fish and Wildlife Service, U.S. Forest Service and the World Wide Fund for Nature in conjunction with the Puerto Rico Department of Natural and Environmental Resources (White et al. 2012). Major intervention to preserve the species began in 1968, involving provision of highly successful artificial nest sites, control of nest predators and competitors, and captive breeding and reintroduction. The success of newly fledged parrots is monitored using radio telemetry (Meyers 1996).
All remaining habitat is protected in the El Yunque National Forest (formerly the Caribbean National Forest) (Snyder et al. 2000) and the Río Abajo Commonwealth Forest (T. White in litt. 2012). The population is monitored to help inform management decisions.
Controlling exotic mammalian predators (trapping and toxic baiting) has been shown to be a highly cost-effective way of conserving the species (Engeman et al. 2003, 2006; R. M. Engeman in litt. 2012). Trapping data has found the Luquillo Forest to have among the highest Black Rat densities studied in the world, and optimal rat baiting strategies have been devised for application during nesting. Economic analyses based on empirical production costs for captive-bred parrots showed very high benefit-cost ratios for predator management, estimating that the prevention of one parrot loss every 4–12 years more than offsets all forms of predator management (for all species) in the intervening time (Engeman et al. 2003).
There are two captive-breeding centres, one at El Yunque, which was first established in 1973 with a new facility constructed in 2007, and one at Río Abajo, constructed in 1989 with the first birds transferred from El Yunque to Río Abajo in 1993 (White et al. 2012). 300 birds are currently held at El Yunque with a further 212 individuals held at the Río Abajo aviary (M. Lopez-Flores in litt. 2019). The captive birds are being managed to preserve as much genetic diversity as possible. A release technique known as "precision release" was trialled with six birds in 2008. This involves releasing a small number of captive-reared subadult parrots at each active nest site immediately following the fledging of the chicks, and aims to promote immediate and close interaction between the wild parrots and released birds (T. White in litt. 2005, 2008). Nearly 100 birds have been released from the Río Abajo aviary in an attempt to establish a second population, which may be aided by lower annual rainfall at the site, lower levels of predation and a change in management techniques (T. White in litt. 2012). Although post-release mortality remains high, successful breeding has been recorded, including post-Hurricane Maria (Gilardi 2018), and the size and range of the flock is increasing (Breining 2009; Valentin 2009; T. White in litt. 2012). The newly establishing population at Río Abajo is located around the site of the Río Abajo aviary; it is thought that the presence of the captive birds has encouraged the released birds to establish their population nearby (White et al. 2012). Forty individuals were released at El Yunque between 2000 and 2004, eight in 2008 and six birds in 2010 (Vélez-Valentín 2011); a further 30-35 birds were planned for release in January 2020 (M. Lopez-Flores in litt. 2019). In 2013, plans were made to establish a third population on the island in the Maricao State Forest (western Puerto Rico) (Anon. 2014a).
Following Hurricanes Irma and Maria in 2017, parrots persist in the Río Abajo forest, but staff are providing supplementary food and providing shaded areas as much of the canopy has been destroyed (Milpacher 2017).
Conservation Actions Proposed
Continue to monitor population trends and establish the overall population trajectory following Hurricanes Irma and Maria (2017). Track the fate of released birds. Maintain the integrated conservation management programme. Improve synchronisation of breeding of wild and captive birds to increase the number of captive-bred chicks that can be fostered by wild parents (Thompson 2004). Integrate exotic mammalian predator control (Black Rats, Small Indian Mongooses, feral cats) into the existing conservation management programme, and monitor predator populations to study the efficacy of these measures (R. M. Engeman in litt. 2012).
30 cm. Green parrot with red forecrown, white eye-ring and blue two-toned primaries. Similar spp. Introduced Hispaniolan Parrot A. ventralis has white forehead, maroon belly and blue in wing extends on to secondaries. Red-crowned Parrot A. viridigenalis has more extensive red on crown and red-orange wing-patch, but is very local around the coast and unlikely to occur sympatrically. Voice Noisy. Wide variety of squawks and screeches. Bugling flight call.
Text account compilers
Wheatley, H., Everest, J.
Anadon, V., Ashpole, J, Benstead, P., Bird, J., Butchart, S., Calvert, R., Engeman, R., Isherwood, I., Khwaja, N., Lopez-Flores, M., Sharpe, C.J., Symes, A., Temple, H., Thompson, J., Wege, D., Westrip, J.R.S. & White, T.
BirdLife International (2021) Species factsheet: Amazona vittata. Downloaded from http://www.birdlife.org on 28/10/2021. Recommended citation for factsheets for more than one species: BirdLife International (2021) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 28/10/2021.