The House Finch (Haemorhous mexicanus) is a moderately sized member of the finch family, Fringillidae. Adult birds measure between 12.5 to 15 centimeters in length, with a wingspan stretching from 20 to 25 centimeters. Their body mass can range from 16 to 27 grams, with an average weight around 21 grams. They possess a long, square-tipped brown tail and exhibit a brown or dull-brown coloration across their back, with deep gray shading on the wing feathers.
Adult males are distinguished by their reddish heads, necks, and shoulders, with this color sometimes extending to the belly and back. The intensity of the male's coloration varies with the seasons and diet, ranging from pale straw-yellow to bright orange and deep red. Adult females have brown upperparts with streaked underparts.
House Finches are found in urban and suburban areas, as well as semi-open regions in the west, from southern Canada to Oaxaca, Mexico.
Originally native to Mexico and the southwestern United States, House Finches have been introduced to eastern North America and Hawaii. They are permanent residents throughout their range, with some northern and eastern populations migrating southward.
These finches are known to forage on the ground or in vegetation. They are also frequent visitors to bird feeders, especially those stocked with sunflower or nyjer seed. House Finches are known to be aggressive in defending feeding territories.
The House Finch has a cheerful and melodic song, characterized by a long, jumbled warbling composed of short notes.
During courtship, males may feed the females, mimicking the feeding of chicks. Females lay clutches of eggs from February through August, with 2 to 6 eggs per brood. The female incubates the eggs for about 12 to 14 days, and both parents feed the young.
The House Finch can be confused with the Purple Finch and Cassin's Finch, but can be distinguished by its longer, less notched tail and different song.
Their diet consists mainly of grains, seeds, and berries. They are particularly fond of weed seeds such as nettle and dandelion, and may also consume small insects like aphids.
The IUCN Red List classifies the House Finch as Least Concern, with an estimated population ranging from 267 million to 1.7 billion individuals across North America.
House Finches may be affected by parasites such as Plasmodium relictum and Mycoplasma gallisepticum. They are also hosts to the mite Pellonyssus reedi, particularly in nests later in the season. The Brown-headed Cowbird may parasitize their nests, but the cowbird chicks rarely survive due to the finch's plant-based diet for their young.