PhoCarpodacus mexicanus

House Finches, small brown birds (the male has red, orange, or yellow cap, breast and rump), are common permanent residents in much of Texas. Their story is one of the most fascinating in modern ornithology. The species was once mostly sedentary and in western North America. About 1940 a few dozen House Finches were brought from Los Angeles, CA, to New York City by cage-bird dealers. The dealers released their captives on Long Island, NY, when they feared a raid by federal authorities. The population increased slowly and then began an explosive expansion. By 1981 the eastern breeding range of House Finch covered the Northeastern and Mid-Atlantic states, and Virginia as well as parts of adjacent states. Development of the ability to migrate south in winter by House Finches probably facilitated this expansion. By 1992 the western boundary had reached the western edge of southern Minnesota, Iowa, Missouri, and parts of Arkansas, Louisiana, Nebraska and Oklahoma (Hill 1993). Population expansion has continued since then, but more slowly (Sauer et al. 2003).

House Finch males achieve an adult-like plumage in their first fall molt, in contrast to Purple (C. purpureus) and Cassin’s (C. cassinii) finches which achieve red plumage only in their second fall. The ability of both sexes to attract mates in the first summer after hatching may have aided their rapid range expansion. Variation in the color of males is determined by their diets. Yellow and orange plumages are more common in arid areas.

DISTRIBUTION. In Texas the TBBA data gathered from 1987-1992 and Breeding Bird Survey (BBS) maps indicate House Finches are widespread west of the 100th meridian (the east boundary of the Panhandle). South of the 32nd parallel, the edge of the historic range continued east to the 97th meridian, south to the 30th parallel, then roughly southwest to the Rio Grande River at the 28th parallel. Results from the BBS routes agrees with the TBBA map as closely as one might expect, given the coarser scale of the BBS method.

Elsewhere in North America House Finches breed at densities of 2 birds or more per BBS route in south British Columbia eastward to the Canadian Rockies, then south though Washington, western Oregon, California, Arizona and New Mexico. Areas of House Finch population are also found in southern Idaho, Nevada, Utah, Colorado and western Nebraska.

In the east highest summer population densities are found from eastern Wisconsin, Michigan, extreme southern Ontario, New York, Vermont, New Hampshire, and southern Maine, south to southern Illinois, Kentucky and Virginia with additional populations in the highlands of the Carolinas, Tennessee and Georgia. Many of these eastern birds migrate to the south for the winter (Sauer et al. 2003). In Mexico House Finches are permanent residents south to Oaxaca and Veracruz (Howell and Webb 1995).

SEASONAL OCCURRENCE. This species in Texas is a permanent resident, so Possible and Probable records are also useful in defining the range of House Finch. Eggs have been collected from March 18 to August 4 (Oberholser 1974). Of 37 instances of Confirmed breeding found by TBBA field workers most dates were from May, June, and July within the overall period of April 1 to July 28. House Finches in the western United States may raise several broods per year (Harrison 1979). Data are not available on the presence in winter of migrants from other states.

BREEDING HABITAT. House Finches in west Texas breed in a variety of habitats from 120 to 2100 m (400 to 7000 ft). The species adapts readily to towns and cities. The birds prefer drier areas with less than 90 cm (35 in) of rain annually (Oberholser 1974). Nests have been found in many situations including on tree limbs, in bird boxes, on projections from structures, even in an old Cliff Swallow (Petrochelidon pyrrhonota) nest. House Finches may reuse nests for a second brood in the same or another year. The cup is usually well constructed of plant fiber (grasses, forbs, rootlets) lined with finer material. The clutch size is 3-6, usually 5 eggs, which are incubated by the female for 12-14 days (Oberholser 1974, Harrison 1979). Young birds leave the nest 12-15 days after hatching (Kaufman 1996).

STATUS House Finches are uncommon to locally common throughout most of Texas. The species is still rare to very rare in the contact zone (running from the east edge of the Balccones Escarpment to the central Gulf Coast) where the eastern and western populations meet (Sauer et al. 2003, Lockwood and Freeman 2004), Oberholser (1974) described an earlier range expansion in Texas to the eastern Edwards Plateau and Austin, in the 1930’s. With the adaptability of this species to suburban and farm situations, it should be present in Texas for many years.

Abundance data from the BBS show averages per 40 km (25 mile) route as high as 4-10 birds per route (Sauer et al. 2003). Since males defend only a small area around the nest (Hill 1993), in sites with many nests under-counting may occur. Long-term trend data are ambiguous; the expanding east Texas population could obscures possible declines elsewhere in the state.  Text by Robert C. Tweit (2004)

Literature cited:
Harrison, H. H. 1979. A field guide to western birds’ nests. Houghton Mifflin, Boston, MA.

Hill, G. E. 1993. House Finch (Carpodacus mexicanus). In The birds of North America, No. 46 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.

Howell, S. N. G., and S. Webb. 1995. A guide to the birds of Mexico and Northern Central America. Oxford University Press, New York.

Kaufman, K. 1996. Lives of North American birds. Houghton Mifflin, Boston MA.

Lockwood, M. W. and B. Freeman. 2004. The TOS handbook of Texas birds. Texas A&M University Press, College Station.

Oberholser, H. C.  1974.  The bird life of Texas. University of Texas Press, Austin.

Sauer, J. R., J. E. Hines, and J. Fallon. 2003. The North American Breeding Bird Survey, results and analysis 1966-2002. Version 2003.1. USGS Patuxent Wildlife Research Center, Laurel MD (URL= http://www.mbr-pwrc.usgs.gov/bbs).