Finches
Finches
Cardueline finches in North America
Finches are species of arboreal, perching birds that make up the large, widespread family, the Fringillidae. There are two subfamilies in this group, the largest being the Carduelinae or cardueline finches, a geographically widespread group that contains more than 130 species. The subfamily Fringillinae or fringillid finches consists of three species of chaffinches that breed in woodlands of Eurasia.
Species of finches occur in North and South America, Africa, Europe, and Asia. In addition, a few species have been introduced beyond their natural range, to Australasia.
Species of finches can occur in a wide range of habitats, including desert, steppe, tundra, savannas, woodlands, and closed forests. Finches that breed in highly seasonal, northern habitats are migratory, spending their non-breeding season in relatively southern places. A few other northern species wander extensively in search of places with abundant food, and breed there. Other species of more southerly finches tend to be residents in their habitat.
It should be noted that in its common usage, the word “finch” is a taxonomically ambiguous term. Various types of seed-eating birds with conical bills are commonly referred to as finches, including species in families other than the Fringillidae. For example, the zebra finch (Taeniopygia guttata ) of Asia is in the waxbill family, Estrildidae, and the snow finch (Montifringilla nivalis ) is in the weaver-finch family, Ploceidae. The “typical” finches, however, are species in the family Fringillidae, and these are the birds that are discussed in this entry.
Biology of cardueline finches
The cardueline or typical finches are smallish birds, with a strong, conical beak, well designed for extracting and eating seeds from cones and fruits. These finches also have a crop, an oesophageal pouch used to store and soften ingested seeds, and a muscular gizzard for crushing their major food of seeds. They eat buds, soft fruits, and some insects.
Most species of finches are sexually dimorphic, with male birds having relatively bright and colorful plumage, and the female being more drab, and cryptic. This coloration helps the female to blend into her surroundings while incubating her eggs, a chore that is not shared by the brightly colored male.
Species of finches occur in Europe, Asia, Africa, and the Americas. However, the greatest diversity of species occurs in Eurasia and Africa.
Cardueline finches typically occur in flocks during their non-breeding season. Many of the northern species of finches are highly irruptive in their abundance, sometimes occurring in unpredictably large populations, especially during their non-breeding season. These events of great abundance are associated with a local profusion of food, for example, at times when conifer trees are producing large quantities of cones and seeds. Crossbills, siskins, and redpolls are especially notable in this respect.
The flight of cardueline finches is strong, and often occurs in an up-and-down, undulating pattern. This flight pattern may be exaggerated during nuptial and territorial displays.
Male cardueline finches defend a territory during their breeding season, mostly by singing, often while the bird is in flight. The songs of most species are loud and melodious. The nest is cup-shaped, and may be placed in a tree, shrub, on the ground, and sometimes in a cavity in piles of rocks. The clutch size is larger in northern species and populations, and can be as few as three and as large as six. The female incubates the bluish-tinged eggs, but she is fed by the male during her seclusion. Both sexes share in the rearing of the young birds.
Cardueline finches in North America
Fifteen species in the Fringillidae breed regularly in North America, all of them cardueline finches. The most prominent of these are discussed below.
The pine grosbeak (Pinicola enucleator ) breeds in conifer-dominated and mixedwood forests across northern North America, and as far south as California and New Mexico. The pine grosbeak is a relatively large, robin-sized finch. Males are a pinkish red color, with black wings, while females are a more cryptic grayish olive. This species has a holarctic distribution, also occurring widely in Europe and Asia, ranging from Scandinavia to Japan.
The purple finch (Carpodacus purpureus ) breeds in a wide range of coniferous and mixedwood forests, and also in open but treed habitats, such as orchards and regenerating cutovers. The plumage of males is a bright purple-red, especially around the head, while females are a streaked olive in coloration. The purple finch breeds widely across the central regions of North America. Cassin’s finch (C. cassinii ) is a closely related, similar-looking species of open coniferous
forests of the western mountains. The house finch (C. mexicanus ) is also a western species, with males being rather rosy in their plumage. In recent decades, the house finch has greatly expanded its range into eastern North America. This process was initiated by introductions of this species to Long Island in 1940, by cagebird dealers who were hoping to establish a local population of house finches to supply the pet trade.
The rosy finch (Leucostricte arctoa ) breeds in western North America, from the Aleutian Islands of Alaska, south through British Columbia and Alberta to Oregon and Montana. This species breeds in upland, rocky tundras, and then descends in the winter to lowlands with a more moderate climate. The rosy finch will frequent bird feeders in the wintertime.
The crossbills (Loxia spp.) are interesting finches, with unique mandibles that cross at their rather elongated tips. This unusual bill is very effective at prying apart the scales of conifer cones, particularly those of species of pines, to extract the nutritious seeds that are contained inside. The red crossbill (L. curvirostra ) ranges very widely, breeding in coniferous forests in North America, across Europe and Asia, in North Africa, even in montane forests in the Philippines.
The white-winged crossbill (L. leucoptera ) occurs in more-open coniferous and mixedwood forests, and it also breeds widely across North America and in Eurasia. Males of both species of crossbills are red colored, with black wings, while females are a dark olive-gray.
The crossbills are also interesting in that they are irruptive breeders and will attempt to nest at almost any time of year, as long as there is a good, local supply of conifer seeds. Northern populations will even breed in the wintertime. Crossbills are great wanderers and can show up unpredictably in large numbers in years when their food is locally abundant, and then disappear for several years, breeding elsewhere until the local crop of pine cones increases again.
The common redpoll (Carduelis flammea ) breeds in coniferous boreal forests and high-shrub tundras of northern Canada, and in similar habitats in northern Europe and Asia. The hoary redpoll (C. hornemanni ) breeds further to the north in more sparsely vegetated tundras, also in both North America and Eurasia. The hoary redpoll breeds as far north on land as is possible in North America, at the very tip of Ellesmere Island. The pine siskin (C. tristis ) breeds further to the south in coniferous and mixedwood forests, as far south as the highlands of Guatemala in Central America.
The American goldfinch (Carduelis tristis ), sometimes known as the wild canary, is a familiar species that breeds widely in North America. The usual habitat is in disturbed situations, such as regenerating burns and cutovers, weedy fields, and shrubby gardens. Male American goldfinches are brightly colored with a yellow-and-black pattern, while females are a paler, olive-yellow. This species is rather partial to the seeds of thistles, which are herbaceous plants that tend to fruit late in the growing season. As a result, goldfinches breed rather late in the summer, compared with almost all other birds within its range. The lesser goldfinch (C. psaltria ) occurs in the southwestern United States and Mexico.
The evening grosbeak (Hesperiphona vespertinus ) breeds in conifer-dominated forests of southern Canada and the western United States. This yellow-and-black bird wanders widely in the wintertime in search of food, and it can sometimes occur in the southern states during this season.
Cardueline finches elsewhere
The common canary or wild serin (Serinus canaria ) is a famous songster, native to the Azores, Madeira, and Canary Islands off northwestern Africa. Wild birds have a gray-olive, streaked back, and a yellowish face and breast. However, this species has been domesticated, is available in a wide range of colors, and is commonly kept as a singing cagebird.
The European goldfinch (Carduelis carduelis ) is a common and widespread species in Europe, western Asia, and northern Africa. This red-faced bird is much-loved in Europe, and as a result several attempts were made by homesick European immigrants to introduce the species to North America. These introductions failed, which is probably just as well, because this species might have caused ecological damages by competing with native species of finches. The European greenfinch (C. chloris ) is another closely related species that is also widespread in Europe. Both of these finches are commonly kept as cagebirds.
The hawfinch (Coccothraustes coccothraustes ) is a widespread Eurasian species. The hawfinch has a large beak, used for crushing large, hard fruits of trees.
Fringillinae finches
The subfamily Fringillinae is comprised of only three species of finches that breed widely in Europe and Asia. These are superficially similar to the cardueline finches, but they do not have a crop, and they feed their young mostly insects, rather than regurgitated seeds and other plant matter.
The common chaffinch (Fringilla coelebs ) has a wide breeding range across northern Eurasia. The male chaffinch has a black head and back, an orange-buff breast, and a white belly, while the coloration of the female is less bright.
The brambling (Fringilla montifringilla ) is also a widespread breeder across northern Eurasia. The brambling also occurs during its migrations in western Alaska, particularly on some of the Aleutian Islands, where flocks of this species may be observed. The male brambling has a blue head, pinkish brown face and breast, a greenish rump, and black and white wings, while the female is a relatively drab, olive-gray.
The blue chaffinch (F. teydea ) only occurs in conifer forests on the Canary Islands. The male is a rather uniformly slate-blue, and the female is a darker gray.
Finches and humans
Because they are attractive and often abundant birds, are easy to feed, and usually sing well, species of finches have long been kept as cagebirds. The most famous of the pet finches is, of course, the canary, but goldfinches and other species are also commonly kept, particularly in Europe. The canary is available in a wide variety of plumages, postures, and song types, all of which have been selectively bred from wild-type birds to achieve some aesthetic goal, which as often as not is focused on the development of birds that are “different” and unusual. The most commonly kept variety of canary is colored bright yellow, and has a richly cheerful, melodic song.
Species of cardueline finches are among the more common species of birds that visit seed-bearing feeders. This is particularly true during the wintertime, when natural seeds can be difficult to find, because they are hidden under accumulated snow. Most of the finches of North America will visit feeders, but their abundance can vary tremendously from week to week and from year to year, depending on the regional availability of wild foods, and also on the weather.
Bird feeding has a rather substantial economic impact. Each year, millions of dollars are spent by North American homeowners to purchase and provision backyard feeders. This money is rather well-spent, in view of the aesthetic pleasures of luring finches and other wild birds close to the home, while
KEY TERMS
Holarctic —This is a biogeographic term, used in reference to species that occur in suitable habitat throughout the northern regions of North America, Europe, and Asia.
Irruption —A periodic, sporadic, or rare occurrence of a great abundance of a species. Some species of migratory finches are irruptive, especially in their winter populations.
also helping these attractive, native species of wildlife to survive their toughest time of the year.
A few species of finches are considered to be agricultural pests. The bullfinch (Pyrrhula pyrrhula ) of Eurasia can be especially important, because it eats the buds of fruit trees, and can cause considerable damages in orchards in some places within its range.
Some finches have become rare and endangered due to changes that humans have incurred to their habitats.
Resources
BOOKS
Beadle, D., and J.D. Rising. Tanagers, Cardinals and Finches of the United States and Canada: A Photographic Guide. Princeton, NJ: Princeton University Press, 2006.
Clement, P., A. Harris, and J. Davis. Finches and Sparrows: An Identification Guide. Princeton, NJ: Princeton University Press, 1993.
Ehrlich, P., D. Dobkin, and D. Wheye. The Birders Handbook. New York: Simon and Schuster, 1989.
Farrand, J., ed. The Audubon Society Master Guide to Birding. New York: Knopf, 1983.
Forshaw, Joseph. Encyclopedia of Birds. 2nd ed. New York: Academic Press, 1998.
Trollope, J. The Care and Breeding of Seed-eating Birds. Dorset, UK: Blandford Press, 1983.
Bill Freedman