About Haemorhous mexicanus (P.L.Statius Müller, 1776)
The house finch (Haemorhous mexicanus) is a moderately sized finch. It measures 12.5 to 15 cm (5 to 6 inches) in length, with a wingspan ranging from 20 to 25 cm (8 to 10 inches). Its body mass varies between 16 to 27 g (9⁄16 to 15⁄16 ounces), with an average weight of 21 g (3⁄4 ounce). Standard measurements for the species are: wing chord 7 to 8.4 cm (2+3⁄4 to 3+1⁄4 inches), tail 5.7 to 6.5 cm (2+1⁄4 to 2+1⁄2 inches), culmen 0.9 to 1.1 cm (3⁄8 to 7⁄16 inches), and tarsus 1.6 to 1.8 cm (5⁄8 to 11⁄16 inches). Adult house finches have a long, square-tipped brown tail, with brown or dull-brown backs and deep gray shading on wing feathers. Breast and belly feathers may be streaked, and flanks are usually streaked. For most adult males, the head, neck, and shoulders are reddish; this red color sometimes extends to the belly and down the back between the wings. Male coloration intensity changes with the seasons, and the color comes from berries and fruits in the bird's diet. As a result, male color ranges from rare pale straw-yellow or bright orange to deep, intense red. Adult females have brown upperparts and streaked underparts. The house finch's song is typically a series of high-pitched musical jumbles that ends with a distinct high note, wheer. In flight, house finches produce a soft cheet or wheat call, while perched birds give a more drawn-out version of this call. Most house finches are permanent residents across their range, though some migrate south, and adult females travel longer migration distances than males. Their breeding habitat includes urban and suburban areas across North America, as well as various semi-open areas in western North America from southern Canada to the Mexican state of Oaxaca. The population in central Chiapas may be descended from escaped cage birds. Analysis of over a century of house finch nest records from California found that egg-laying happens significantly earlier in warmer springs. House finches were originally only residents of Mexico and the southwestern United States. They were introduced to eastern North America in the 1940s, when they were sold illegally in New York City under the marketing name "Hollywood finches". Vendors and owners released the birds to avoid prosecution under the 1918 Migratory Bird Treaty Act. Since release, house finches have become naturalized in eastern North America, and have displaced the native purple finch and even the non-native house sparrow across largely unforested land of the eastern United States. In the 19th century, house finches were introduced to Hawaiʻi, and are now found on all major Hawaiian islands except Niʻihau and Kahoʻolawe. The Partners in Flight database estimates there are 40 million house finches across North America. Cases of naturalization from escaped or released cage birds have also been recorded in Europe, including a 2020 record in Murcia, Spain.
