Oilbird Steatornis caripensis is the only known
nocturnal avian frugivore; a cave-dwelling species
that forms colonies in caves or crevices, usually
(see below) where no daylight penetrates5,13,19–21.
It occurs from Costa Rica and Panama, across the
tropical Andes, on Trinidad, and in the Guianas, in
varied habitats to 3,080 m2,3,12,13,19–22. In Ecuador,
most colonies are on the east slope of the Andes,
with the only conrmed colony away from there in
an inter-Andean valley (Quebrada de Alchipichi,
prov. Pichincha15). However, in Colombia colonies
have also been recorded from the west slope1,8,13,16,19.
Scattered records of wandering birds suggest
the presence of additional colonies elsewhere in
Ecuador, with reports across the west and east
Andean slopes7,10,15,16 and the Cordillera de la
Costa, an isolated range in coastal Ecuador6. Here,
we present new data that signicantly extend
the altitudinal and geographic ranges of Oilbird
in Ecuador, including the discovery of four new
Two of these newly discovered colonies are
the rst for the west Andean slope. In north-west
Ecuador, AS-U & AA-T visited a property 30 km
north-east of Armenia (Table 1) on 30 March
2008. They were taken to a steep canyon (40–50
m high and 3–5 m wide) with several waterfalls:
50–60 birds were roosting on the rock walls. Six
to eight pairs had chicks or juveniles, and a naked
chick was found dead in the stream. Vegetation
around the canyon provided sufcient cover to
limit light for most of the day, except between
10h00 and 11h00, when most birds are exposed
to sunlight. In south-west Ecuador, BAT learnt of
a colony in the inter-Andean valley of Yunguilla,
at Chalcapac (Table 1). Two visits (August 2005,
February 2007) to the area conrmed that Oilbirds
occupied crevices on the rock wall at the conuence
of the ríos Rircay and Burro. Pastures dominate
the landscape here but some native forest persists
in inaccessible areas. Local people conrmed that
Oilbirds are year-round residents and nests have
been found. Individuals from this colony may
account for records in El Oro and Loja provinces16.
Two new colonies were found on the east
Andean slope. GB-J learnt from Quichua
indigenous people the location of a colony (<30
birds) in the Pusuno Valley, Cordillera de Galeras
(Table 1). Two juveniles captured for oil extraction
were given to him in March 2001. The large cave
network in the area may host additional colonies.
This locality is the easternmost in Ecuador and the
rst reported colony for prov. Napo. On 5 March
2008, AS-U was taken to an Oilbird cave by Shuar
indigenous people, c.3.5 km from Shaime, in the
southern Cordillera del Cóndor (Table 1). About 40
birds were present, with 5–6 pairs having juveniles.
The cave lies within hilly terra rme forest; the
entrance is 2 m high by 4–5 m wide, descends for
3–4 m to the bottom, and is crossed by a small
New data on the distribution of Oilbird Steatornis caripensis
Diego F. Cisneros-Heredia, Pierre-Yves Henry, Galo Buitrón-Jurado, Alejandro Solano-Ugalde,
Agustina Arcos-Torres and Boris A. Tinoco
Received 12 January 2011; ﬁnal revision accepted 30 June 2011
Cotinga 34 (2012): OL 28–31
published online 10 March 2012
Reportamos nuevos datos que extienden signicativamente el rango altitudinal y de distribución
del Guácharo Steatornis caripensis en Ecuador. Presentamos información sobre cuatro colonias
reproductivas recientemente descubiertas, dos en la vertiente occidental de los Andes (prov.
Pichincha y Azuay) y dos en la vertiente oriental (prov. Napo y Zamora-Chinchipe); dos registros
que extienden el rango altitudinal de la especie hasta 3.650 m; un gran conjunto de registros que
conrman la presencia de la especie en el área de Quito, extendiendo su rango regular en Ecuador
hacia los valles interandinos del norte, entre 2.750 y 3.100 m de altitud; y nuevos registros en la
vertiente noroccidental de los Andes que complementan la información de la presencia estacional
de los guácharos en esa región. Discutimos sobre la naturaleza de los registros en relación con
las capacidades de movimiento de la especie, hipotetizando si corresponden a viajes de forrajeo
diarios, movimientos estacionales o individuos errantes. Algunas colonias de guácharos pueden
estar en peligro de desaparecer debido a la destrucción de los hábitats, pero el conocimiento sobre
esta especie en Ecuador es muy fragmentado, sin información conable respecto a su estado de
conservación. Hacemos un llamado urgente a los investigadores para que incrementen sus esfuerzos
de estudio sobre estas fascinantes aves. Dado que son usadas por comunidades indígenas locales,
las colonias de estas aves podrían convertirse en una atracción turística rentable y apreciada, si son
estudiadas, manejadas y cosechadas sustentablemente.
New data on the distribution of Oilbird in Ecuador
Many records from Quito (prov. Pichincha)
extend the regular range in Ecuador to the inter-
Andean valleys at 2,750–3,100 m. Ridgely &
Greeneld16 reported the main altitudinal range of
Oilbird in Ecuador as 700–2400 m, with wanderers
reaching 2,600 m. They overlooked reports by
Salvadori & Festa18 and Ortiz-Crespo15 of specimens
collected within Quito. Recent records (Table 1)
attest that the species still regularly occurs there. A
specimen (QCA 774, Museo Zoología, Universidad
Católica Ecuador) was collected in November 1985
in the city. Singles were observed in February 1994
(roosting in a small ravine at Parque Metropolitano
de Quito—PMQ), May 1994 (roosting on a
Eucalyptus), August 1998 (ying at night), January
and July between 1997 and 2002 (ying birds at
night or roosting by day on abandoned buildings in
the lower part of Bosque Protector del Pichincha),
November 2008 (roosting on a Prunus serotina
in Ashintaco ravine, PMQ), January 2009 (ying
almost nightly in the Cumbayá Valley, near Quito),
October 2009 (roosting by day on a building near
PMQ), April 2010 (ying at night in the lower part
of Bosque Protector del Pichincha) and June 2010
(ying at night at Cumbayá). Additionally, three
were captured, on 22 December 1993, 11 April
1996 and 15 June 1997, in city gardens and taken
to Aves&Conservación and released in the xeric
valley of the río Guayllabamba (north of Quito) or
Two records extend the altitudinal range to
3,650 m. Around 15 June 2004, an Oilbird with
a broken wing was found by local people at the
village of Pulug (Table 1), an inter-Andean valley
in the watershed of the río Chambo. The bird died
a few days later and P-YH examined it on 1 July
2004. The landscape is dominated by agricultural
lands with sparse Eucalyptus. On 5 May 2001,
GB-J found a dead bird at the edge of Papallacta
lagoon (Table 1). It was rather well preserved and
exhibited the typical size and coloration of the
species. This record is the highest anywhere in the
New records were also made on the north-west
slope of the Andes. Small groups (<5) or singles
were recorded annually, mainly in August–March
in 1998–2005, and also in April 2010, at Río
Guajalito Protected Forest (Table 1), a montane
cloud forest. Despite regular visits (at least ten
days, six times p.a.), larger numbers (5–25) were
detected only three times, in October–February
1998–2005 (DFCH et al. pers. obs.). In February
2009, March 2009 and January 2010, small groups
(4–8) were observed at Yunguilla (Table 1), which
records complement the data of Freile & Chaves10
concerning seasonal occurrence of Oilbirds on the
north-west Andean slope of Ecuador.
These opportunistic records from several ‘new’
areas for the species in Ecuador should be discussed
in the light of the species’ known movements.
Oilbirds are highly mobile, ranging far from their
colonies when foraging. Movements have been
classied as follows: (i) daily foraging travels, (ii)
seasonal movements, and (iii) wandering. Daily
foraging travels are well studied in Venezuela.
The home range of a breeding colony extended
over c.97 km2, with a max. distance between
feeding localities of 150 km and max. daily foraging
distance of c.200 km in one night4,11,17; the records
from Quito, Pulug and Papallacta are all within
150 km of a known colony, and may all reect birds
engaged in daily foraging. Seasonal movements
are still poorly documented and understood. At
some colonies, most birds engage in post-breeding
migrations (whereas some remain year-round at
the colonies4). Post-breeding migration probably is
inuenced by local food shortages4,5,17,18,21. This is
the case at Venezuelan, Colombian and Ecuadorian
colonies, where Oilbirds perform post-breeding
migrations, unlike Trinidad colonies which occupy
nesting caves year-round4,5,11,13,19–21. Birds on
post-breeding migration have been found at caves
Table 1. Localities mentioned in the text for new records of Oilbird Steatornis caripensis in Ecuador.
Name Province Coordinates Elevation (m) Type
Chalcapac Azuay 03°14.8’S 79°12.4’W 1,320 Colony
Pulug Chimborazo 01°32’S 78°42’W 3,280 Dead bird
Río Pusuno Valley Napo 00º52S 77º35W 1,200 Colony
Papallacta Napo 00°22S 78°10W 3,650 Dead bird
Tiputini Biodiversity Station Orellana 00°37’S 76°10’W 190–270 Sight records
30 km north-east of Armenia Pichincha 00º13’N 78º43’W 900 Colony
Quito Pichincha 00º13’S 78º30’W 2,750–3,100 Sight records
Guajalito Pichincha 00°14’S 78°49’W 1,900–2,100 Sight records
Shaime Zamora-Chinchipe 04º20’S 78º39’W 900 Colony
New data on the distribution of Oilbird in Ecuador
45 km from their colonies11 and birds recorded at
Guajalito could be seasonal migrants. Wandering
movements usually involve individuals or small
groups foraging far from their breeding or roosting
caves, in areas where the species is rare. In
Ecuador, such individuals have been reported
in the eastern lowlands, e.g., at Cuyabeno16 and
Tiputini Biodiversity Station (Table 1; regular
records mainly in June–August, in 1999–2010, of
singles either ying at night or roosting on trees by
day; DFCH pers. obs.).
It has been suggested that Oilbirds can inhabit
agricultural areas3,4,11,17. However, extensive habitat
destruction and expansion of agriculture coupled
with total forest removal is doubtless negatively
affecting Ecuadorian colonies, as in Venezuela,
where three colonies in heavily modied areas
have become extinct3,4. There are no reliable data
on the conservation status of Ecuadorian colonies,
but extensive habitat destruction in inter-Andean
valleys (e.g., Alchipichi and Chalcapac) could also
provoke extinction in the short term. Colonies
on Andean slopes are probably more ‘insulated’,
being located in forested areas, but it remains to
be quantied how chick harvesting and habitat
modication affect populations, especially where
habitat fragmentation is intense.
Improved knowledge on the distribution of
Oilbird in Ecuador will require the discovery,
preservation and evaluation of colonies, foraging
and post-breeding areas. Surveys at colonies should
be undertaken during the breeding season to
evaluate their true size. Oilbirds make fascinating
research subjects; they are used by indigenous
communities, and could become highly appreciated
and protable tourism attractions, if adequately
studied and sustainably harvested.
We thank Catalina Landeta Salgado, Fanny Paucar
Muñoz, David Parra, the Mamallacta family,
Francisco Sánchez, Xavier Fernandes de Córdova,
Maria Elena Heredia, Laura Heredia, Roberto Phillips,
Andrés León-Reyes and Vlastimil Zak for eld work
participation and support; Santiago Burneo and Luis
Coloma for permission to examine the QCA collection,
and Hugo Balseca for sharing his data.
1. Albuja. L. & de Vries, T. (1977) Aves colectadas y
observadas alrededor de la Cueva de los Tayos,
Morona-Santiago, Ecuador. Rev. Univ. Católica
2. Bosque, C. (1978) La distribución del Guácharo en
Venezuela. Bol. Soc. Venez. Espel. 9: 29–48.
3. Bosque, C. (1986) Actualización de la distribución
del Guácharo (Steatornis caripensis) en
Venezuela. Bol. Soc. Venez. Espel. 22: 1–10.
4. Bosque, C. & Ramírez, R. (1988) Post-breeding
migration of Oilbirds. Wilson Bull. 100: 675–677.
5. Bosque, C., Ramírez, R. & Rodríguez, D. (1995)
The diet of the Oilbird in Venezuela. Orn.
Neotrop. 6: 67–80.
6. Carrasco, L., Cook, A. & Karubian, J. (2008) Range
extensions for eight species of bird in the Mache-
Chindul mountains, Ecuador. Cotinga 29: 72–76.
7. Carrión, J. M. & Ortiz-Crespo, F. (1991)
Introduccion a las aves del Ecuador. Quito:
8. Chwinda, A., Flanagan, J., Jiggins, C., Sukanga,
T. & Willis, J. (1997) Manejo sostenible de
una cueva de tayos Steatornis caripensis en la
Cordillera del Cóndor. Cotinga 8: 8–9.
9. Fjeldså, J. & Krabbe, N. (1990) The birds of the
high Andes. Copenhagen: Zool. Mus., Univ. of
Copenhagen & Svendborg: Apollo Books.
10. Freile, J. F. & Chaves, J. A. (2004) Interesting
distributional records and notes on the biology
of bird species from a cloud forest reserve in
north-western Ecuador. Bull. Brit. Orn. Club
11. Gutiérrez, P. C. (1994) Mitochondrial-DNA
polymorphism in the Oilbird (Steatornis
caripensis, Steatornithidae) in Venezuela. Auk
12. Herrera F. F. (2003) Distribución actualizada de
las colonias de guacharos (Steatornis caripensis)
en Venezuela. Bol. Soc. Venez. Espel. 37: 31 – 40.
13. Hilty, S. L. & Brown, W. H. (1986) A guide to
the birds of Colombia. Princeton, NJ: Princeton
14. McAtee, W. L. (1922) Notes on the food of the
Guacharo (Steatornis caripensis). Auk 39:
15. Ortiz-Crespo, F. (1979) Discovery of an Oilbird
colony in the western drainage of the Ecuadorian
Andes. Auk 96: 187–189.
16. Ridgely, R. S. & Greeneld, P. J. (2001) The
birds of Ecuador. Ithaca, NY: Cornell University
17. Roca, R. (1994) Oilbirds of Venezuela: ecology
and conservation. Cambridge, MA: Nuttall
18. Salvadori, T. & Festa, E. (1900) Viaggio del Dr.
Enrico Festa nell’Ecuador. XXII. Uccelli, Parte
terza – Trochili-Tinami. Boll. Mus. Zool. Anat.
Comp. 15(368): 1–54.
19. Snow, B. K. (1979) The Oilbirds of Los Tayos.
Wilson Bull. 91: 457–461.
20. Snow, D. W. (1961) The natural history of the
Oilbird, Steatornis caripensis, Trinidad. W. I.
Part 1, General behavior and breeding habits.
Zoologica 46: 26–48.
21. Snow, D. W. (1962) The natural history of the
Oilbird, Steatornis caripensis, in Trinidad, W. I.
Part 2. Population, breeding ecology and food.
Zoologica 47: 199–221.
22. Thomas, B. T. (1999) Family Steatornithidae
(Oilbird). In: del Hoyo J., Elliott, A. & Sargatal,
J. (eds.) Handbook of the birds of the world, 5.
Barcelona: Lynx Edicions.
New data on the distribution of Oilbird in Ecuador
Diego F. Cisneros-Heredia
Universidad San Francisco de Quito, Colegio de
Ciencias Biológicas & Ambientales, Campus Cumbayá,
Edif. Darwin, of. DW-010A, calle Diego de Robles y Vía
Interoceánica, CP 17-1200-841, Quito, Ecuador; King’s
College London, Department of Geography, London,
UK; and, Aves&Conservación (BirdLife Ecuador),
UMR 7179 CNRS MNHN CF, Département Ecologie et
Gestion de la Biodiversité, Muséum National d’Histoire
Naturelle, 91800 Brunoy, France.
Museo de Zoología, Ponticia Universidad Católica del
Ecuador, Escuela de Biología, Ponticia Universidad
Católica del Ecuador, Quito, Ecuador.
Alejandro Solano-Ugalde and Agustina Arcos-
Fundación Imaymana, Quito, Ecuador.
Boris A. Tinoco
Universidad del Azuay, Escuela de Biología del Medio
Ambiente, Cuenca, Ecuador.