The House finch (Haemorhous mexicanus) is a small songbird native to North America. This species and the other "American rosefinches" are placed in the genus Haemorhous.
Adult House finches have long, square-tipped brown tails and are a brown or dull-brown color across the back with some shading into deep gray on the wing feathers. Breast and belly feathers may be streaked; the flanks usually are. In most cases, adult males' heads, necks, and shoulders are reddish. This color sometimes extends to the belly and down the back, between the wings. Male coloration varies in intensity with the seasons and is derived from the berries and fruits in its diet. As a result, the colors range from pale straw-yellow through bright orange (both rare) to deep, intense red. Adult females have brown upperparts and streaked underparts.
House finches are found in southern Canada, across the U.S.A., and Mexico. These birds are mainly permanent residents throughout their range but some northern and eastern populations migrate south. House finches inhabit urban and suburban areas, as well as various semi-open areas in the west from southern Canada to the Mexican state of Oaxaca.
House finches are active during the day and usually spend time in small groups or flocks. They feed mainly on the ground or in vegetation and are frequent visitors to bird feeders throughout the year, and often congregate at hanging nyjer sock feeders. House finches communicate using visual postures and vocalizations. Their song is a rapid, cheery warble or a variety of chirps. Males sing during courtship, while the female is constructing the nest, and during the incubation periods. Females usually sing during the courtship period.
House finches are herbivores (granivores, frugivores) and primarily eat grains, seeds, and berries, being voracious consumers of weed seeds such as nettle and dandelion. They may sometimes consume small insects such as aphids.
House finches are monogamous and form pairs. Their breeding season occurs between March and August. Females are typically attracted to males with the deepest pigment of red on their heads. During courtship, the male will touch bills with the female. He may then present the female with choice bits of food, and if she mimics the behavior of a hungry chick, he may actually feed her. The male also feeds the female during breeding and incubation of the eggs and raising of the young, and the male is the primary feeder of the fledglings. House finches nest in cavities, including openings in buildings, hanging plants, and other cup-shaped outdoor decorations. Sometimes nests abandoned by other birds are also used. Nests may be re-used for subsequent broods or in the following years. The nest is built by the female, sometimes in as little as two days. It is well made of twigs and debris, forming a cup shape, usually 1.8 to 2.7 m (5 ft 11 in to 8 ft 10 in) above the ground. The female may produce two or more broods per year with 2 to 6 eggs per brood, most commonly 4 or 5. The eggs are pale bluish-green with few black spots and a smooth, somewhat glossy surface. Incubation takes 12-14 days and is done by the female. The chicks hatch altricial; they are pink with closed eyes and tufts of fluffy down. The female always feeds the young, and the male usually joins in. The young are silent for the first 7 or 8 days, and subsequently, start peeping during feedings. Before flying, the chicks often climb into adjacent plants and usually fledge at about 11 to 19 days after hatching. Dandelion seeds are among the preferred seeds fed to the young. While most birds, even ones with herbivorous leanings as adults, tend to feed their nestlings animal matter in order to give them the protein necessary to grow, House finches are one of the few birds who feed their young only plant matter.
There are no major threats to House finches at present.
According to Wikipedia resource, the total population size of the House finch is anywhere between 267 million to 1.7 billion individuals. Currently, this species is classified as Least Concern (LC) on the IUCN Red List, and its numbers today are increasing.
House finches help to disperse seeds throughout their ecosystem and also provide food for local predators such as birds of prey, snakes, squirrels, rats, and domestic cats.