The olive finch (''Arremon castaneiceps'') is a species of
bird
Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweigh ...
in the family
Passerellidae
New World sparrows are a group of mainly New World passerine birds, forming the family Passerellidae. They are seed-eating birds with conical bills, brown or gray in color, and many species have distinctive head patterns.
Although they share t ...
. Until recently, it was placed in the
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
''
Lysurus''.
It is found in the
Andes
The Andes, Andes Mountains or Andean Mountains (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long, wide (widest between 18°S – 20°S ...
of
Colombia
Colombia (, ; ), officially the Republic of Colombia, is a country in South America with insular regions in North America—near Nicaragua's Caribbean coast—as well as in the Pacific Ocean. The Colombian mainland is bordered by the Car ...
,
Ecuador
Ecuador ( ; ; Quechua: ''Ikwayur''; Shuar: ''Ecuador'' or ''Ekuatur''), officially the Republic of Ecuador ( es, República del Ecuador, which literally translates as "Republic of the Equator"; Quechua: ''Ikwadur Ripuwlika''; Shuar: ''Eku ...
and far northern
Peru
, image_flag = Flag of Peru.svg
, image_coat = Escudo nacional del Perú.svg
, other_symbol = Great Seal of the State
, other_symbol_type = Seal (emblem), National seal
, national_motto = "Fi ...
where its natural
habitat
In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...
is subtropical or tropical moist
montane forest
Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures fall as elevation increases, causing the ecosystem to stratify. This stratification is a crucial f ...
. The olive finch is listed as Near Threatened by the
IUCN Red List
The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...
.
The olive finch is related to the
sooty-faced finch and ornithologist
Carl Eduard Hallmayr even suggested they should be classified as the same species.
Distribution and Habitat
The olive finch is found in humid, low mountain forests, often near ravines, forest edges, rivers, and streams. It is found at elevations between 700-2200 meters in Columbia, 800-1800 m in Ecuador, and 750-1800 m in Peru.
Appearance
The olive finch has olive green plumage with a chestnut crown and nape.
The face and throat are dark gray, and the wings and tail are darker in color than the rest. The tail is more rounded compared to other
Arremon
''Arremon'' is a genus of neotropical birds in the family Passerellidae. With the exception of the green-striped brushfinch which is endemic to Mexico, all species are found in South America, with a few reaching Central America.
These sparr ...
species. A juvenile olive finch presents similarly to adults but with a duller crown, olive throat and face, and uneven plumage coloration. More specific information on the bird’s molt and its timing is not available for this species. It has a brown or dark brown iris, black or dark gray bill, and black tarsi and toes.
The olive finch has a length of 15.5-16.5 cm from the beak to end of its tail. Its linear measurements include a wingspan of 82-83 mm for males and a wingspan of approximately 76 mm for females, along with an average tail length of 66 mm. Their mass is between 34.5-39 grams for males and 32-35 grams for females.
Breeding and Nesting
The olive finch breeding season takes place in March, April, and June. Nests are large domes with a side entrance, often covered in moss, vines, ferns, or roots, and made of woven root pieces, bamboo leaves and fresh fern leaves. Nests are located on stream banks or vegetation near running water. Clutches contain 2 eggs which are mostly white but sometimes have small red-brown speckles concentrated near the larger end of the egg. Little information on sexual behavior exists but they are often seen in pairs.
Diet
The olive finch forages in the understory of the forest,
along with on the ground moving by hopping.
Little is known on the diet of the olive finch but it is presumed to include seeds, along with reported findings of insect parts in its stomach contents.
References
{{Taxonbar, from=Q1934333
olive finch
Birds of the Colombian Andes
Birds of the Ecuadorian Andes
olive finch
olive finch
Taxonomy articles created by Polbot