BirdLife species factsheet for Black-billed Amazon
Black-billed Amazon (Amazona agilis) is endemic to Jamaica, where it occurs from Cockpit Country to Mount Diablo and in the John Crow Mountains. It inhabits wet limestone forest and forest edge, but also uses cultivated land and plantations adjacent to forest for foraging (Collar 1997, BirdLife Jamaica in litt. 1998, Juniper and Parr 1998). The population has preliminarily been placed in the band 10,000-19,999 individuals (S. Koenig in litt. 2008), roughly equating to 6,000-15,000 mature individuals, though this number requires confirmation.
The species is impacted by a variety of threats, which drive a rapid population decline. The species is projected to decline drastically by the end of the 21st century (Koenig 2008). Shifting cultivation, logging and bauxite mining have reduced suitable habitat (BirdLife Jamaica in litt. 1998, Juniper and Parr 1998). Bauxite mining concessions granted in 2008 in Cockpit Country, which supports the largest part of the population, are causing a gradual loss in forested habitat (Koenig 2008). The frequency of droughts is increasing as a consequence of climate change, which deteriorates the habitat quality and causes the range to contract, as individuals concentrate around fruiting trees near villages in the southern part of the range (L. Gibson in litt. 2020). Furthermore, instances of cross-breeding with Puerto Rican Amazon Amazona vittata are observed occasionally, possibly because hurricances and droughts drive individuals of Puerto Rican Amazon to Jamaica, where a small population may already have established in Cockpit Country (L. Gibson in litt. 2020, Cawley et al. in press). Black-billed Amazon is further threatened by nest predation by invasive species (including rats, mongooses and boas; Davis 1997, L. Gibson in litt. 2020, Cawley et al. in press). Trapping for the cage-bird trade is taking place, but only at low numbers (Wright et al. 2001, Gibson in press).
Black-billed Amazon is currently listed as Vulnerable under Criteria A3c; B1ab(i,ii,iii,v) (BirdLife International 2020). However, new information regarding the threats the species is facing and the population trend suggests that the species may warrant a change in Red List status. Therefore, it will be re-assessed against all criteria:
Criterion A – The species is undergoing a rapid decline at an accelerating rate, which is projected to continue over the next decades (Koenig 2008). This decline is caused by moderate rates of tree cover loss (Koenig 2008, Tracewski et al. 2016, Global Forest Watch 2020), deterioration of habitat quality due to a higher frequency of droughts, increased risk of hybridisation with Puerto Rican Amazon, an increase in invasive nest predators, and hunting for the pet trade (L. Gibson in litt. 2020, Cawley et al. in press). The rate of decline is placed in the band 50-79% over three generations (31.8 years; Bird et al. 2020)*, and Black-billed Amazon qualifies for listing as Endangered under Criterion A3ced+A4cde.
Criterion B – The Extent of Occurrence (EOO) for this species is 5,100 km2; the maximum Area of Occupancy (AOO), as calculated by a 4 km2 grid over the area of mapped range, is 3,156 km2. Hence, the EOO meets the threshold for Vulnerable (EOO < 20,000 km2). However, in order to be listed under this criterion, at least two further conditions have to be met.
Observational records of the species are fairly continuous throughout the range (eBird 2020), and therefore the species is not severely fragmented sensu ICUN (see IUCN Standards and Petitions Committee 2019). The species is facing a variety of threats (see Cawley et al. in press). The most severe threat, whose impacts can potentially extirpate large parts of the population within the next three generations, is thought to be the loss and deterioration of habitat due to high levels of logging and an increased frequency of droughts. Furthermore, nest predation by invasive species can have detrimental effects, including in areas that are to date relatively secure from logging and droughts. The species is therefore considered to occur at 6-10 locations**, and hence subcriterion a is met at the level of Vulnerable. The species’s EOO and AOO are contracting, the quality of habitat is deteriorating, and the species is projected to undergo a rapid decline (L. Gibson in litt. 2020), and subcriterion b(i,ii,iii,v) is met. The species is not known to undergo extreme fluctuations, and thus subcriterion c is not met. Therefore, Black-billed Amazon qualifies for listing as Vulnerable under Criterion B1ab(i,ii,iii,v).
Criterion C – The population size of Black-billed Amazon has been placed in the band 6,000-15,000 mature individuals. Assuming that the true population size is closer to the lower end of the estimate, this meets the threshold for listing as Vulnerable under Criterion C. However, to do so fully, a species must meet further conditions.
Due to the combined impacts of habitat deterioration and loss, hybridisation, hunting and predation by invasive species, Black-billed Amazon is projected to undergo a continuing decline with a likely rate of 50-79% over three generations; thus subcriterion 1 is met. Moreover, even though we have no direct information on the subpopulation structure, we can tentatively assume that the species forms only one subpopulation, and subcriterion 2a(ii) is met. Therefore, the species qualifies for listing as Vulnerable under Criterion C1+2a(ii).
Criterion D – The population size and range are too large to warrant listing as threatened under Criterion D, and therefore Black-billed Amazon is considered Least Concern under this criterion.
Criterion E – To the best of our knowledge no quantitative analysis of extinction risk has been conducted for this species. Therefore, it cannot be assessed against this criterion.
Therefore, it is suggested that Black-billed Amazon (Amazona agilis) be listed as Endangered under Criterion A3cde+4cde. It is here assumed that the species crossed the threshold for listing as EN during the period 2016-2020. We welcome any comments on the proposed listing and timing of change.
Please note that this topic is not designed to be a general discussion about the ecology of the species, rather a discussion of its Red List status. Therefore, please make sure your comments are relevant to the discussion outlined in the topic. By submitting a comment, you confirm that you agree to the Comment Policy.
*Bird generation lengths are estimated using the methodology of Bird et al. (2020), as applied to parameter values updated for use in each IUCN Red List for birds reassessment cycle. Values used for the current assessment are available on request. We encourage people to contact us with additional or improved values for the following parameters; adult survival (true survival accounting for dispersal derived from an apparently stable population); mean age at first breeding; and maximum longevity (i.e. the biological maximum, hence values from captive individuals are acceptable).
**The term ‘location’ refers to a distinct area in which a single threatening event can rapidly affect all individuals of the taxon present, with the size of the location depending on the area covered by the threatening event. Where a taxon is affected by more than one threatening event, location should be defined by considering the most serious plausible threat (IUCN 2001, 2012).
An information booklet on the Red List Categories and Criteria can be downloaded here and the Red List Criteria Summary Sheet can be downloaded here. Detailed guidance on IUCN Red List terms and definitions and the application of the Red List Categories and Criteria can be downloaded here.
Bird, J. P.; Martin, R.; Akçakaya, H. R.; Gilroy, J.; Burfield, I. J.; Garnett, S.; Symes, A.; Taylor, J.; Şekercioğlu, Ç. H.; Butchart, S. H. 2020. Generation lengths of the world’s birds and their implications for extinction risk. Conservation Biology online first view.
BirdLife International. 2020. Species factsheet: Amazona agilis. http://www.birdlife.org (Accessed 06 April 2020).
Cawley, R.; Gibson, L.; Wright, C.; White, O.; Rowe, D. in press. New and increasing threats may have significant impact on the distribution and abundance of Jamaica’s black-billed parrot (Amazona agilis). Oryx.
Collar, N. J. 1997. Psittacidae (Parrots). In: del Hoyo, J.; Elliott, A.; Sargatal, J. (ed.). Handbook of the birds of the world, pp. 280-477. Lynx Edicions, Barcelona, Spain.
eBird. 2020. eBird: An online database of bird distribution and abundance [web application]. eBird, Ithaca, New York. http://www.ebird.org (Accessed 06 April 2020).
Gibson, L. in press. Bycatch of the Day: Wild meat consumption, ecological knowledge, and symbolic capital among indigenous Maroon parrot hunters of Jamaica. Journal of Ethnobiology.
Global Forest Watch. 2020. Interactive Forest Change Mapping Tool. http://www.globalforestwatch.org (Accessed 06 April 2020).
IUCN. 2001. IUCN Red List Categories and Criteria: Version 3.1. IUCN Species Survival Commission. IUCN, Gland, Switzerland and Cambridge, U.K.
IUCN. 2012. IUCN Red List Categories and Criteria: Version 3.1. Second edition. IUCN Species Survival Commission. IUCN, Gland, Switzerland and Cambridge, U.K. www.iucnredlist.org/technical-documents/categories-and-criteria.
IUCN Standards and Petitions Committee. 2019. Guidelines for using the IUCN Red List Categories and Criteria. Version 14. http://www.iucnredlist.org/documents/RedListGuidelines.pdf.
Juniper, T.; Parr, M. 1998. Parrots: a guide to the parrots of the world. Pica Press, Robertsbridge, UK.
Koenig, S. E. 2008. Black-billed Parrot (Amazona agilis) Population Viability Assessment (PVA): A science-based prediction for policy makers. Ornitología Neotropical 19: 1-15.
Tracewski, Ł.; Butchart, S. H. M.; Di Marco, M.; Ficetola, G. F.; Rondinini, C.; Symes, A.; Wheatley, H.; Beresford, A. E.; Buchanan, G. M. 2016. Toward quantification of the impact of 21st-century deforestation on the extinction risk of terrestrial vertebrates. Conservation Biology 30: 1070-1079.
Wright, T. F.; Toft, C. A.; Enkerlin-Hoeflich, E.; Gonzalez-Elizondo, J.; Albornoz, M.; Rodrígues-Ferraro, A.; Rojas-Suárez, F.; Sanz, V.; Rujillo, A.; Beissinger, S. R.; Berovides A., V.; Gálvez A., X.; Brice, A. T.; Joyner, K.; Eberhard, J.; Gilardi, J.; Koenig, S. E.; Stoleson, S.; Martuscelli, P.; Meyers, J. M.; Renton, K.; Rodríguez, A. M.; Sosa-Asanza, A. C.; Vilella, F. J.; Wiley, J. W. 2001. Nest poaching in Neotropical parrots. Conservation Biology 15(3): 710-720.