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IUCN 2008: T22723786A77574068
Camarhynchus heliobates, Mangrove Finch
Assessment by: BirdLife International
View on www.iucnredlist.org
Citation: BirdLife International. 2015. Camarhynchus heliobates. The IUCN Red List of Threatened
Species 2015: e.T22723786A77574068. http://dx.doi.org/10.2305/IUCN.UK.20154.RLTS.T22723786A77574068.en
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THE IUCN RED LIST OF THREATENED SPECIES™
Taxonomy
Kingdom
Phylum
Class
Order
Family
Animalia
Chordata
Aves
Passeriformes
Emberizidae
Taxon Name: Camarhynchus heliobates (Snodgrass & Heller, 1901)
Common Name(s):
• English:
Mangrove Finch
Taxonomic Source(s):
SACC. 2006. A classification of the bird species
#http://www.museum.lsu.edu/~Remsen/SACCBaseline.htm#.
of
South
America.
Available
at:
Identification Information:
14 cm. Dull, brownish finch. Dull brownish upperparts, more olive on rump. Whitish below with faint
streaking. Pale, pointed bill and dark legs. Males can get black hoods with age as do other tree finch
species Similar spp. Very similar to Woodpecker Finch Cactospiza pallida, but has smaller bill, some faint
streaking on underparts and is slightly browner. Woodpecker finches are not known to get black hoods.
Song is best way to differentiate from Woodpecker Finch. Voice Sequence of two-five tur notes, each
phrase being repeated up to three times.
Assessment Information
Red List Category & Criteria:
Critically Endangered B1ab(i,ii,iv,v)+2ab(i,ii,iv,v); C2a(i); D ver 3.1
Year Published:
2015
Date Assessed:
October 1, 2015
Justification:
This species has an extremely small, severely fragmented range, and potentially as few as two viable
subpopulations. Recent surveys suggest that the number of locations and mature individuals are both
declining, and consequently it qualifies as Critically Endangered.
Previously Published Red List Assessments
2013 – Critically Endangered (CR) – http://dx.doi.org/10.2305/IUCN.UK.20132.RLTS.T22723786A49626449.en
2012 – Critically Endangered (CR)
2010 – Critically Endangered (CR)
2009 – Critically Endangered (CR)
2008 – Critically Endangered (CR)
2004 – Critically Endangered (CR)
© The IUCN Red List of Threatened Species: Camarhynchus heliobates – published in 2015.
http://dx.doi.org/10.2305/IUCN.UK.2015-4.RLTS.T22723786A77574068.en
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2000 – Critically Endangered (CR)
1996 – Endangered (EN)
1994 – Endangered (EN)
1988 – Threatened (T)
Geographic Range
Range Description:
This species is restricted to the Galápagos Islands, Ecuador. Historically, it was known from at least six
mangrove patches on east Fernandina and east, south and west Isabela (Vargas 1997). Recent surveys
have failed to record the species on Fernandina, and it seems likely that it is now extinct as a breeding
bird on the island - the last reported sighting may have been in 1971 (Grant and Grant 1997). In 1997
and 1998, surveys on Isabela found breeding populations in only two areas, Playa Tortuga Negra and
Caleta Black on the north-west coast of the island, with estimated populations of 37 and 21 pairs
respectively (Grant and Grant 1997, Vargas 1997). Subsequent surveys have estimated the population at
36 and 16 pairs in 1999 (Vargas 1999), 24 and 14 pairs in 2007 (B. Fessl in litt. 2007), and perhaps the
most thorough surveys to date recorded c. 40 pairs in each in 2009 (Fessl et al. 2010). Surveys in the
fairly extensive mangroves on the south-east coast of Isabela found three to five territories which
probably contained breeding birds, but further areas of potentially suitable habitat remain unsurveyed
(Dvorak et al. 1997, Dvorak et al. 2004). In 2008 several other historical sites were surveyed including
Punta Espinoza (Fernandina), Bahia Elizabeth, Punta Moreno and Bahia Urbina, but the only site at
which birds were located was Cartago Bay (Fessl et al. 2010, G. Young and B. Fessl in litt. 2008), from
which the species is now thought extirpated, with no records from the area since 2009 (G. Young in litt.
2012).
Country Occurrence:
Native: Ecuador (Galápagos)
© The IUCN Red List of Threatened Species: Camarhynchus heliobates – published in 2015.
http://dx.doi.org/10.2305/IUCN.UK.2015-4.RLTS.T22723786A77574068.en
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Distribution Map
© The IUCN Red List of Threatened Species: Camarhynchus heliobates – published in 2015.
http://dx.doi.org/10.2305/IUCN.UK.2015-4.RLTS.T22723786A77574068.en
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Population
The population is estimated to number 50-100 individuals (G. Young in litt. 2013) and 40-80 mature
individuals (F. Cunninghame and G Young in litt. 2013).
Trend Justification
In 1997 surveys on Isabela found breeding populations in only two areas, Playa Tortuga Negra and
Caleta Black on the north-west coast of the island, with estimated populations of 37 and 21 pairs
respectively (Grant & Grant 1997, Vargas 1997); but from 2006 to 2009 territory mapping only revealed
a maximum of 27 and 15 pairs (B. Fessl et al. 2010). This equates to a decline of 20-29% over 10 years
(three generations). However, trends appear to have stabilised since, and the population may even now
be increasing (G. Young in litt. 2012).
Current Population Trend: Decreasing
Habitat and Ecology (see Appendix for additional information)
It inhabits dense mangrove swamps, where it feeds on insects, larvae, spiders and some vegetable
matter (Dvorak et al. 1997, Vargas 1997, Dvorak et al. 2004, Fessl et al. 2011). Its breeding season
coincides with the beginning of heavy rainfalls, normally in December and January, and generally lasts
until the end of the rainy season, around May, although successful nesting has been recorded as late as
September (G. Young in litt. 2011). Nests are placed in tall trees within patches of high mangroves that
are often flooded at high tide, a habitat that is rare on the Galápagos (Fessl et al. 2011). Mangroves used
by the species in the north-west appear to be structurally different from areas where it is absent
suggesting it has subtle habitat preferences and suffers from habitat degradation (Dvorak et al. 2004,
Fessl et al. 2011). It appears to favour mangrove with tall trees, relatively low canopy cover and
abundant leaf litter and dead wood (Dvorak et al. 2004, Fessl et al. 2011). A separation of the
mangroves from the sea seems to be crucial as this prevents the washing out of leaf litter etc., which
represents the species's preferred feeding substrates (Dvorak et al. 2004, Fessl et al. 2011).
Systems: Terrestrial
Threats (see Appendix for additional information)
This species is declining owing to predation and disease as a result of the presence of invasive species.
Rattus rattus abundance is high at both breeding sites and is believed to be the major reason for the
high nesting failure due to predation (70% in 2007) and low fledgling success (Fessl et al. 2010). Other
possible introduced predators include feral cats (especially important during the post-fledging phase),
Smooth-billed Ani Crotophaga ani and fire ants Solenopsis spp., although fire ants seemed to have been
successfully exterminated in 1997 (Grant and Grant 1997, Vargas 1997, 1999). The blood-sucking nest
parasite Philornis downsi represents a significant threat, as it is present in all nests and infestation is high
(with a mean of 42 parasites per nest). The first case of nesting mortality due to Philornis parasitisation
was recorded in 2007, and this threat is becoming relatively more prominent as invasive rodents are
now controlled (G. Young in litt. 2012). Avian pox may also represent a significant threat to the species,
which may also be inherently susceptible to the effects of inbreeding (Fessl et al. 2010). Research has
shown that the species favours structurally distinct mangroves and hence may be susceptible to human
modification of this habitat, and it may be especially susceptible to sea level rise driven by climate
change (D. Wiedenfeld in litt. 2012). Habitat loss through the felling of large trees and collection of
© The IUCN Red List of Threatened Species: Camarhynchus heliobates – published in 2015.
http://dx.doi.org/10.2305/IUCN.UK.2015-4.RLTS.T22723786A77574068.en
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wood for fires may be a threat near Puerto Villamil (Young et al. 2013).
Conservation Actions (see Appendix for additional information)
Conservation and Research Actions Underway
The habitat of this species is protected within the Galápagos National Park and, in 1979, the islands
were declared a World Heritage Site, although this was classified as threatened in 2007. An action plan
was published 2010 (in English and Spanish) following a workshop in 2008. Predator control is ongoing
as are studies into the control of Philornis downsi, with a workshop on this specific subject held in early
2012 (G. Young and B. Fessl in litt. 2008, G. Young in litt. 2011, Fessl et al. 2010, Charles Darwin
Foundation 2014). A study of breeding biology commenced in 1999 (Vargas 1999) and a follow up study
started in 2006. Blood samples are being analysed to investigate the genetic structure of the remaining
population and to clarify whether hybridisation is occurring, although preliminary results for the latter
are negative (H. Vargas and F. Cruz in litt. 2000). Preliminary results, however, do appear to indicate that
the species is highly inbred (Fessl et al. 2010).
A Darwin Initiative funded Mangrove Finch project coordinated by Galápagos National Park, Durrell
Wildlife Conservation Trust and the Charles Darwin Foundation began in 2007 (G. Young in litt. 2007)
with the aim of clarifying the need and proceedings for a breeding or translocation project. Possible
sites for reintroduction have been visited on Isabela and habitat suitability assessments undertaken.
Remote mapping of mangrove has taken place throughout Isabela with the aim of locating suitable sites,
and captive trials have used Woodpecker Finch in order to train personnel and develop husbandry
techniques that were then transferred to Mangrove Finch (G. Young and B. Fessl in litt. 2008). The first
trial translocation took place in May 2010 when nine wild-trapped birds were taken to Bahia Urbina (25
km south of Playa Tortuga Negra) following intense rat control at this site (Cunninghame et al. 2011).
Translocated birds proved hardy and, while able to find sufficient food and habitat at release site, may
have returned to their source site (where one male was recorded after c.6 months). A conservation
education programme has engaged local schoolchildren, and produced a film highlighting the species's
importance. A course has been run for local guides (G. Young in litt. 2011). In 2014, the head-starting
and release of young was trialled and plans are in place to continue this in 2015 (G. Young in litt. 2014).
Conservation and Research Actions Proposed
Continue to survey for further populations. Establish yearly monitoring at Playa Tortuga Negra and
Caleta Black. Continue control measures for rats, wasps, ants, cats and fire ants at Playa Tortuga Negra
and Caleta Black, and monitor effects on the population (Grant and Grant 1997). Further study the
impact of Philornis downsi on adults and nestlings, and develop effective control methods, which may
include application of control agents directly into nests (D. Wiedenfeld in litt. 2012), pheromone
disturbance, or the release of sterile males (Charles Darwin Foundation 2014). Study the impact of
Galapagos Hawk Buteo galapagoensis. Facilitate printing of the species action plan in Spanish and
English (G. Young in litt. 2011). Restore the Ramsar site at Vilamill. Establish translocation techniques to
re-establish individuals at former sites following rat control, using head-started young birds less likely to
return to their natal site (G. Young in litt. 2012). A recent study found that some species of Darwin's
finches can be encouraged to 'self-fumigate' their nests through the provision of permethrin-treated
cotton fibres, resulting in the significantly fewer P. downsi and more successfly fledged offspring. It is
suggested this may be an effective method of reducing nestling mortality for the Mangrove Finch
(Knutie et al. 2014).
© The IUCN Red List of Threatened Species: Camarhynchus heliobates – published in 2015.
http://dx.doi.org/10.2305/IUCN.UK.2015-4.RLTS.T22723786A77574068.en
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Credits
Assessor(s):
BirdLife International
Reviewer(s):
Symes, A.
Contributor(s):
Cruz, F., Fessl, B., Vargas, H., Young, G., Wiedenfeld, D. & Cunninghame, F.
Facilitators(s) and
Compiler(s):
Benstead, P., Bird, J., Harding, M., Isherwood, I., McClellan, R., Pople, R., Sharpe, C
J, Symes, A., Khwaja, N. & Wright, L
© The IUCN Red List of Threatened Species: Camarhynchus heliobates – published in 2015.
http://dx.doi.org/10.2305/IUCN.UK.2015-4.RLTS.T22723786A77574068.en
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Bibliography
Charles Darwin Foundation. 2014. Philornis downsi: Buscando Una Solución. Available at:
https://youtu.be/38QmSV6WAVY. (Accessed: 07/08/2015).
Cunninghame, F.; Young, H. G.; Fessl, B. 2011. A trial conservation translocation of the Mangrove Finch
in the Galápagos Islands, Ecuador. In: Soorae, P.S. (ed.), Global reintroduction perspectives 3, pp. 151156. Environment Agency, Abu Dhabi.
Dvorak, M.; Tebbich, S.; Fessl, B. 1997. Mangrove Finch Survey 1997 on the south-eastern coast of
Isabela, Galápagos Islands.
Dvorak, M.; Vargas, H.; Fessel, B.; Tebbich, S. 2004. On the verge of extinction: a survey of the mangrove
finch Cactospiza heliobates and its habitat on the Galápagos Islands. Oryx 38: 171-179.
Fessl, B.; Loaiza, A. D.; Tebbich, S.; Young, H. G. 2011. Feeding and nesting requirements of the Critically
Endangered Mangrove Finch Camarhynchus heliobates. Journal of Ornithology 152: 453-460.
Fessl, B.; Tebbich, S. 2002. Philornis downsi - a recently discovered parasite on the Galápagos
archipelago - a threat for Darwin's finches? Ibis 144: 445-451.
Fessl, B.; Young, H. G.; Young, R. P.; Rodríguez-Matamoros, J.; Dvorak, M.; Tebbich, S.; Fa, J. E. 2010. How
to save the rarest Darwin's finch from extinction: the Mangrove Finch on Isabela Island. Philosophical
Transactions of the Royal Society B: Biological Sciences 365: 1019-1030.
Grant, P. R.; Grant, R. 1997. The rarest of Darwin's Finches. Conservation Biology 11: 119-216.
IUCN. 2015. The IUCN Red List of Threatened Species. Version 2015-4. Available at: www.iucnredlist.org.
(Accessed: 19 November 2015).
Knutie, S.A., McNew, S.M., Bartlow, A.W., Vargas, D.A. and Clayton, D.H. 2014. Darwin’s finches combat
introduced nest parasites with fumigated cotton. Current Biology 24(9): R355-R356.
McCarthy, M. 2009. Desperate bid to save finches that changed the world. Available at:
#http://www.independent.co.uk/environment/nature/desperate-bid-to-save-finches-that-changed-theworld-1722941.html#.
Vargas, H. 1997. Mangrove Finch conservation project.
Vargas, H. 1999. Mangrove Finch conservation project.
Young, H.G., Cunninghame, F., Fessl, B. and Vargas, F.H. 2013. Mangrove Finch Camarhynchus heliobates:
An Obligate Mangrove Specialist from the Galápagos Islands. In: G. Gleason and T.R. Victor (eds),
Mangrove Ecosystems: Biogeography, Genetic Diversity and Conservation Strategies, Nova, New York.
Citation
BirdLife International. 2015. Camarhynchus heliobates. The IUCN Red List of Threatened Species 2015:
e.T22723786A77574068. http://dx.doi.org/10.2305/IUCN.UK.2015-4.RLTS.T22723786A77574068.en
Disclaimer
To make use of this information, please check the Terms of Use.
© The IUCN Red List of Threatened Species: Camarhynchus heliobates – published in 2015.
http://dx.doi.org/10.2305/IUCN.UK.2015-4.RLTS.T22723786A77574068.en
7
External Resources
For Images and External Links to Additional Information, please see the Red List website.
© The IUCN Red List of Threatened Species: Camarhynchus heliobates – published in 2015.
http://dx.doi.org/10.2305/IUCN.UK.2015-4.RLTS.T22723786A77574068.en
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Appendix
Habitats
(http://www.iucnredlist.org/technical-documents/classification-schemes)
Habitat
Season
Suitability
Major
Importance?
1. Forest -> 1.7. Forest - Subtropical/Tropical Mangrove Vegetation Above
High Tide Level
Resident
Suitable
Yes
Threats
(http://www.iucnredlist.org/technical-documents/classification-schemes)
Threat
Timing
Scope
Severity
Impact Score
5. Biological resource use -> 5.3. Logging & wood
harvesting -> 5.3.3. Unintentional effects:
(subsistence/small scale)
Ongoing
Majority (5090%)
Unknown
Unknown
Stresses:
1. Ecosystem stresses -> 1.1. Ecosystem conversion
1. Ecosystem stresses -> 1.2. Ecosystem degradation
Ongoing
Whole (>90%)
Stresses:
2. Species Stresses -> 2.1. Species mortality
Ongoing
Whole (>90%)
Stresses:
2. Species Stresses -> 2.1. Species mortality
Ongoing
Whole (>90%)
Stresses:
2. Species Stresses -> 2.1. Species mortality
Ongoing
Whole (>90%)
Stresses:
2. Species Stresses -> 2.3. Indirect species effects ->
2.3.2. Competition
Ongoing
Whole (>90%)
Stresses:
2. Species Stresses -> 2.3. Indirect species effects ->
2.3.7. Reduced reproductive success
Ongoing
Whole (>90%)
Stresses:
2. Species Stresses -> 2.3. Indirect species effects ->
2.3.7. Reduced reproductive success
8. Invasive & other problematic species & genes ->
8.1. Invasive non-native/alien species -> 8.1.2.
Named species (Felis catus)
8. Invasive & other problematic species & genes ->
8.1. Invasive non-native/alien species -> 8.1.2.
Named species (Crotophaga ani)
8. Invasive & other problematic species & genes ->
8.1. Invasive non-native/alien species -> 8.1.2.
Named species (Solenopsis geminata)
8. Invasive & other problematic species & genes ->
8.1. Invasive non-native/alien species -> 8.1.2.
Named species (Polistes versicolor)
8. Invasive & other problematic species & genes ->
8.1. Invasive non-native/alien species -> 8.1.2.
Named species (Philornis downsi)
8. Invasive & other problematic species & genes ->
8.1. Invasive non-native/alien species -> 8.1.2.
Named species (Rattus rattus)
© The IUCN Red List of Threatened Species: Camarhynchus heliobates – published in 2015.
http://dx.doi.org/10.2305/IUCN.UK.2015-4.RLTS.T22723786A77574068.en
Unknown
Unknown
Unknown
Unknown
Unknown
Unknown
Unknown
Unknown
Unknown
Unknown
Unknown
Unknown
9
11. Climate change & severe weather -> 11.4. Storms
& flooding
Future
Majority (5090%)
Unknown
Unknown
Stresses:
1. Ecosystem stresses -> 1.2. Ecosystem degradation
1. Ecosystem stresses -> 1.3. Indirect ecosystem effects
Conservation Actions in Place
(http://www.iucnredlist.org/technical-documents/classification-schemes)
Conservation Actions in Place
In-Place Research, Monitoring and Planning
Action Recovery plan: Yes
Systematic monitoring scheme: No
In-Place Land/Water Protection and Management
Conservation sites identified: Yes, over entire range
Occur in at least one PA: Yes
Invasive species control or prevention: Yes
In-Place Species Management
Successfully reintroduced or introduced beningly: No
Subject to ex-situ conservation: Yes
In-Place Education
Subject to recent education and awareness programmes: Yes
Included in international legislation: No
Subject to any international management/trade controls: No
Conservation Actions Needed
(http://www.iucnredlist.org/technical-documents/classification-schemes)
Conservation Actions Needed
2. Land/water management -> 2.2. Invasive/problematic species control
2. Land/water management -> 2.3. Habitat & natural process restoration
3. Species management -> 3.2. Species recovery
3. Species management -> 3.4. Ex-situ conservation -> 3.4.1. Captive breeding/artificial propagation
Research Needed
(http://www.iucnredlist.org/technical-documents/classification-schemes)
© The IUCN Red List of Threatened Species: Camarhynchus heliobates – published in 2015.
http://dx.doi.org/10.2305/IUCN.UK.2015-4.RLTS.T22723786A77574068.en
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Research Needed
1. Research -> 1.2. Population size, distribution & trends
1. Research -> 1.5. Threats
1. Research -> 1.6. Actions
3. Monitoring -> 3.1. Population trends
Additional Data Fields
Distribution
Estimated area of occupancy (AOO) (km²): 1
Continuing decline in area of occupancy (AOO): Yes
Extreme fluctuations in area of occupancy (AOO): No
Estimated extent of occurrence (EOO) (km²): 1
Continuing decline in extent of occurrence (EOO): Yes
Extreme fluctuations in extent of occurrence (EOO): No
Number of Locations: 2
Continuing decline in number of locations: Yes
Extreme fluctuations in the number of locations: No
Lower elevation limit (m): 0
Population
Number of mature individuals: 40-80
Continuing decline of mature individuals: Yes
Extreme fluctuations: No
Population severely fragmented: Yes
No. of subpopulations: 2
Continuing decline in subpopulations: Yes
Extreme fluctuations in subpopulations: No
All individuals in one subpopulation: No
No. of individuals in largest subpopulation: 1-89
Habitats and Ecology
Continuing decline in area, extent and/or quality of habitat: Unknown
Generation Length (years): 3.8
© The IUCN Red List of Threatened Species: Camarhynchus heliobates – published in 2015.
http://dx.doi.org/10.2305/IUCN.UK.2015-4.RLTS.T22723786A77574068.en
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Habitats and Ecology
Movement patterns: Not a Migrant
© The IUCN Red List of Threatened Species: Camarhynchus heliobates – published in 2015.
http://dx.doi.org/10.2305/IUCN.UK.2015-4.RLTS.T22723786A77574068.en
12
The IUCN Red List Partnership
The IUCN Red List of Threatened Species™ is produced and managed by the IUCN Global Species
Programme, the IUCN Species Survival Commission (SSC) and The IUCN Red List Partnership.
The IUCN Red List Partners are: BirdLife International; Botanic Gardens Conservation International;
Conservation International; Microsoft; NatureServe; Royal Botanic Gardens, Kew; Sapienza University of
Rome; Texas A&M University; Wildscreen; and Zoological Society of London.
THE IUCN RED LIST OF THREATENED SPECIES™