Data Zone
Justification of Red List category
This species has a small population, which is split further into two small subpopulations. 95% of the overall population is additionally confined to one subpopulation only. It is threatened by the loss and degradation of its habitat, as well as being recently susceptible to climatic events. Consequently, it has been uplisted to Endangered.
Population justification
The remaining pine forest on Abaco and Grand Bahama islands has been estimated between c.360 km2 (Tracewski et al. 2016) and c.500 km2 (Global Forest Watch 2020). However, following Hurricane Dorian, potential remaining habitat is thought to be lower at 227-455 km2 on Abaco, and only 5-23 km2 on Grand Bahama (measured as the extent of non-catastrophically impacted forests remaining; B. Watson, G. Wallace, W. Hayes, and S. Johnson in litt. 2020). The most recent information of population density for the Bahama Warbler, obtained during a survey in 2007, reports 3.6 individuals/km2 on Grand Bahama Island (Lloyd and Slater 2011). This value, however, does not account for non-territorial males and assumes a 1:1 sex ratio (J. Lloyd in litt. 2011). Nevertheless, in the absence of further information, the population density on both islands is tentatively assumed to be 3.6 individuals/km2. Taking into account both remaining habitat following Hurricane Dorian and recent density estimates therefore suggests that 817-1,638 individuals are on Abaco (representing 95% of the population) and 18-83 individuals are on Grand Bahama (B. Watson, G. Wallace, W. Hayes, and S. Johnson in litt. 2020); assumed to form two subpopulations. The overall population therefore numbers 835-1721 individuals, converted to 557-1147 mature individuals and placed in the band of 500-1,200 mature individuals.
Trend justification
The population is inferred to be in decline due to loss and fragmentation of its habitat. There is evidence that the species declined by around 30% between 1969 and 2007 on Grand Bahama (J. Lloyd in litt. 2011). According to remote-sensed data on tree cover loss, an estimated 2.4-6.3% of forest was lost within the species's range over ten years to 2019 (Tracewski et al. 2016, Global Forest Watch 2020). However, following landfall of Hurricane Dorian in September 2019, which caused extensive damage to both Abaco and Grand Bahama's pine forests that was not included in the remote-sensed data, overall forest loss over the past decade is likely to now have been higher (B. Watson, G. Wallace, W. Hayes, and S. Johnson in litt. 2020). It is therefore assumed here that forest loss will likely have been at least 10% or potentially higher in the past and over the next 10 years. The species is additionally thought to now be largely confined to Abaco (representing over 95% of the population). Thus, the overall population is suspected to be undergoing a decline that is placed here in the band of 10-15% decline over 10 years.
This species is endemic to Grand Bahama and Abaco (Great Abaco and Little Abaco) in the northern Bahamas. Surveys in the Caribbean Pine forests of Grand Bahama have found the species to be patchily distributed and existing at low densities (Lloyd and Slater 2011), with relatively higher densities found in the central regions of Grand Bahama (W. K. Hayes in litt. 2011). Its population is thought to have declined since the onset of major logging of pine forests in the mid-20th century (W. K. Hayes in litt. 2011). Large-scale deforestation is suggested to have reduced the area covered by Caribbean Pine forest to 360-500 km2, of which c.400 km2 are situated on Abaco and c.140 km2 on Grand Bahama (Tracewski et al. 2016, Global Forest Watch 2020). More recently however, due to the landfall of Hurricane Dorian, remaining habitat is thought to be restricted to 227-455 km2 on Abaco and 5-23 km2 on Grand Bahama (B. Watson, G. Wallace, W. Hayes, and S. Johnson in litt. 2020).
The species is restricted exclusively to mature stands of Caribbean Pine Pinus caribaea (McKay et al. 2010), where it is patchily distributed and occurs at low densities (Lloyd and Slater 2011). It mainly feeds on insects and other invertebrates (del Hoyo et al. 2020).
The species’s restriction to Caribbean Pine forests makes it highly dependent on the fate of these forests. Overall, pine forests are among the most threatened ecosystems in the Caribbean. They are rapidly cleared for infrastructural developments, mainly for roads as well as for tourism and residential developments. Particularly areas in the vicinity of Freeport and Lucaya on Grand Bahama have been affected (Lloyd and Slater 2011, W. K. Hayes in litt. 2011). Large areas of pine forest have been fragmented and their structure and composition have been altered by changing fire regimes, human activity, hurricanes and subsequent saltwater intrusion (Lloyd and Slater 2011, W. K. Hayes in litt. 2011). Caribbean Pine forests are at high risk of further development and renewed logging (McKay et al. 2010, White 2011). It has been suggested that around half of the existing suitable habitat on Grand Bahama Island may be at risk, which may also hold true for Abaco Island (J. Lloyd in litt. 2011). The recent landfall of Hurricane Dorian in 2019 is additionally thought to have incurred extensive loss to remaining pine forests, including significant crown loss, trees knocked over, and in the worst case, completely unrecoverable (B. Watson, G. Wallace, W. Hayes, and S. Johnson in litt. 2020). 22.5% of pine forests on Abaco were considered 'catastrophically damaged', with 86% of the overall Abaco pine forest range to be 'impacted' by Hurricane Dorian (L. Williams per B. Watson, G. Wallace, W. Hayes, and S. Johnson in litt. 2020). The recent establishment of the Shiny Cowbird (Molothrus bonariensis) is suggested to be a potential threat to the species (del Hoyo et al. 2020).
Conservation Actions Underway
No targeted conservation actions are known for this species.
Conservation Actions Proposed
Carry out surveys, especially on Abaco, in order to refine the population estimate. Conduct regular surveys at selected sites to monitor population trends. Monitor rates of habitat loss and degradation. Challenge detrimental development proposals and raise awareness of the importance of pine forest conservation. Protect areas of suitable habitat. Strengthen protection for habitat already covered by reserve designations. Incorporate management for the species's conservation into forestry plans.
Text account compilers
Fernando, E., Hermes, C.
Contributors
Hayes, W.K., Johnson, S., Lee, D.S., Lloyd, J., Symes, A., Taylor, J., Wallace, G. & Watson, B.
Recommended citation
BirdLife International (2024) Species factsheet: Bahama Warbler Setophaga flavescens. Downloaded from
https://datazone.birdlife.org/species/factsheet/bahama-warbler-setophaga-flavescens on 22/12/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 22/12/2024.