VU
Cape Verde Swamp-warbler Acrocephalus brevipennis



Taxonomy

Taxonomic source(s)
AERC TAC. 2003. AERC TAC Checklist of bird taxa occurring in Western Palearctic region, 15th Draft. Available at: #http://www.aerc.eu/DOCS/Bird_taxa_of _the_WP15.xls#.
Cramp, S. and Simmons, K.E.L. (eds). 1977-1994. Handbook of the birds of Europe, the Middle East and Africa. The birds of the western Palearctic. Oxford University Press, Oxford.
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A., Fishpool, L.D.C., Boesman, P. and Kirwan, G.M. 2016. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 2: Passerines. Lynx Edicions and BirdLife International, Barcelona, Spain and Cambridge, UK.

IUCN Red list criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - B1ab(ii,iii)+2ab(ii,iii)

Red List history
Year Category Criteria
2017 Vulnerable B1ab(ii,iii)+2ab(ii,iii)
2016 Endangered B1ab(i,ii,iii)
2012 Endangered B1ab(i,ii,iii,iv,v)
2008 Endangered B1a+b(i,ii,iii,iv,v)
2004 Endangered
2000 Endangered
1996 Vulnerable
1994 Vulnerable
1988 Lower Risk/Least Concern
Species attributes

Migratory status not a migrant Forest dependency Does not normally occur in forest
Land mass type Average mass -
Extent of occurrence (EOO)

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 13,300 medium
Extent of Occurrence breeding/resident (km2) 1,300
Number of locations 3 -
Fragmentation -
Population and trend
Estimate Data quality Derivation Year of estimate
No. of mature individuals 1500-2000 poor estimated 2009
Population trend Unknown good -
Decline (3 years/1 generation past) - - -
Decline (5 years/1 generation past) - - -
Decline (10 years/1 generation past) - - -
Decline (10 years/3 generation future) - - -
Decline (10 years/3 generation past and future) - - -
Number of subpopulations 3 - - -
Largest subpopulations - - -
Generation length (yrs) 4.4 - - -

Population justification: The population was estimated at c.500 pairs in the early 1990s, and was thought to number 1,000-1,500 birds based on its known range in 2007 (C. J. Hazevoet in litt. 2007). However, conservative estimates of 500 pairs on Fogo mean that the total population is likely to be higher, likely numbering 1,500-2,000 mature individuals, roughly equivalent to 2,200-3,000 individuals in total.  Full censuses were never carried on Fogo or Santiago. The numbers on Santiago could be higher than previously thought because the bird is now known to occur in all vegetated areas of the island, whereas in the 1990s it was thought to be absent from the north of the island (H. Batalha in litt. 2016). On Fogo, a volcanic eruption in 2014 does not seem to have affected the extent of area occupied by the bird, but the bird is absent from areas where it had been previously found on the forest of Monte Velha following the forest fire of 2015. However, the size of the birds’ territories is unknown, and could be larger than in closely related species; this means that the numbers estimated based on replies to playbacks may or may not correspond to the actual numbers (in recent surveys, the same colour-ringed bird replied to playback lures from locations that could have considered two adjacent territories [H. Batalha in litt. 2016]). Surveys on S. Nicolau in three occasions in 2014 and 2016 found 12 – 13 territories each time, and the real number is not likely to be much higher.  There are probably a minimum of 20 birds and a maximum of 50 on that island.

Trend justification: Despite the discovery of a large population on Fogo in 2004 and a report from Tarrafal on Santiago, the overall population was suspected to be declining owing to habitat loss, although substantive evidence of this is lacking (C.J. Hazevoet in litt. 2007). The Fogo population favours coffee plantations and introduced crops and the population may yet prove to be stable.

While the population on S. Nicolau seems to have decreased between the time of its discovery, in the 1860s, and the 1920s, the numbers seem to have stabilised, with approximately the same numbers of birds found in 1998, 2004, 2014 and 2016 (H. Batalha in litt. 2016). On Santiago, the bird was considered to be absent from the northern part of the island in the 1980s and 1990s, but currently it can be found in all latitudes (Batalha et al. 2016); it is not clear whether the birds was really absent on the northern part of the island in the 1980s/1990s or were simply undetected, so current population trends are difficult to infer (H. Batalha in litt. 2016), and it is possible that the species may have as much as doubled in population size (C. Hazevoet in litt. 2012).


Country/territory distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
Cape Verde N Extant Yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Cape Verde Central mountain range of Ilha de São Nicolau
Cape Verde Pedra Badejo lagoons
Cape Verde Serra do Pico da Antónia

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Artificial/Terrestrial Arable Land suitable resident
Artificial/Terrestrial Arable Land suitable resident
Artificial/Terrestrial Plantations suitable resident
Artificial/Terrestrial Plantations suitable resident
Artificial/Terrestrial Rural Gardens suitable resident
Artificial/Terrestrial Rural Gardens suitable resident
Artificial/Terrestrial Urban Areas suitable resident
Artificial/Terrestrial Urban Areas suitable resident
Forest Subtropical/Tropical Dry suitable resident
Shrubland Subtropical/Tropical Dry suitable resident
Shrubland Subtropical/Tropical Moist suitable resident
Shrubland Subtropical/Tropical Moist suitable resident
Wetlands (inland) Bogs, Marshes, Swamps, Fens, Peatlands suitable resident
Wetlands (inland) Bogs, Marshes, Swamps, Fens, Peatlands suitable resident
Altitude 0 - 1384 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Climate change & severe weather Droughts Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation
Climate change & severe weather Droughts Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines
Stresses
Ecosystem degradation
Climate change & severe weather Storms & flooding Timing Scope Severity Impact
Future Minority (<50%) Rapid Declines Low Impact: 4
Stresses
Ecosystem degradation, Reduced reproductive success, Species mortality
Climate change & severe weather Storms & flooding Timing Scope Severity Impact
Future Minority (<50%) Rapid Declines
Stresses
Ecosystem degradation, Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Unspecified species Timing Scope Severity Impact
Future Minority (<50%) Slow, Significant Declines Low Impact: 3
Stresses
Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Unspecified species Timing Scope Severity Impact
Future Minority (<50%) Slow, Significant Declines
Stresses
Species mortality
Invasive and other problematic species, genes & diseases Problematic species/disease of unknown origin - Unspecified species Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Stresses
Species mortality
Natural system modifications Fire & fire suppression - Increase in fire frequency/intensity Timing Scope Severity Impact
Ongoing Minority (<50%) Rapid Declines Medium Impact: 6
Stresses
Ecosystem degradation, Ecosystem conversion, Species mortality
Other options Other threat Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Residential & commercial development Housing & urban areas Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Residential & commercial development Housing & urban areas Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines
Stresses
Ecosystem degradation, Ecosystem conversion

Utilisation
Purpose Primary form used Life stage used Source Scale Level Timing
Pets/display animals, horticulture - - International Non-trivial Recent

Recommended citation
BirdLife International (2019) Species factsheet: Acrocephalus brevipennis. Downloaded from http://www.birdlife.org on 22/05/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 22/05/2019.