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. Areas of House Finch population are also found in southern Idaho, Nevada, Utah, Colorado and western Nebraska. Results from the BBS routes agrees with the TBBA map as closely as one might expect, given the coarser scale of the BBS method.Įlsewhere 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. 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. 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). Yellow and orange plumages are more common in arid areas.ĭISTRIBUTION. Variation in the color of males is determined by their diets. The ability of both sexes to attract mates in the first summer after hatching may have aided their rapid range expansion. cassinii) finches which achieve red plumage only in their second fall. House Finch males achieve an adult-like plumage in their first fall molt, in contrast to Purple (C. Population expansion has continued since then, but more slowly (Sauer et al. 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). Development of the ability to migrate south in winter by House Finches probably facilitated this 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. The population increased slowly and then began an explosive expansion. The dealers released their captives on Long Island, NY, when they feared a raid by federal authorities. About 1940 a few dozen House Finches were brought from Los Angeles, CA, to New York City by cage-bird dealers. The species was once mostly sedentary and in western North America. Their story is one of the most fascinating in modern ornithology. House Finches, small brown birds (the male has red, orange, or yellow cap, breast and rump), are common permanent residents in much of Texas.
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