The distribution of the house finch in Kansas and studies of competition between the house finch and the house sparrow in Kansas during the winter.

Abstract

The winter distribution of the house finch (Carpodacus mexicanus) in Kansas was reviewed from Christmas bird counts (CBC's) that were published in the Kansas Ornithological Society Bulletin. The house finch entered the state from the southwest and has rapidly expanded across Kansas in a northeasterly direction. The house finch was first recorded on a CBC in 1955 in Clark County. The site that has the longest continuous record of house finch sightings is Morton County/cimarron National Grasslands in the southwestern corner of the state. In 1990, the number of house finch sightings on the CBC was 2,807 and the number of counts recording house finches was 23, both the largest numbers recorded for the house finch in Kansas. At present, a second population of house finches may be invading Kansas from the east, however, the majority of house finches in Kansas probably came from the southwest. Competition may occur between the house finch and the house sparrow (Passer domesticus). Analysis of the Kansas Winter Bird Feeder Survey has shown the house finch to outnumber the house sparrow in five southwestern Kansas counties. To test whether the house finch is having an effect on the house sparrow in Kansas, a study was performed in an aviary with same-sex dyads of house finches and house sparrows under winter conditions. The house finch was the more aggressive of the two, but a large variance occurred within individuals, leaving only threats and attacks by female house finches statistically significant in a nested analysis of variance. Given a choice of food, the house finch preferred thistle seed, and the house sparrow seemed to prefer millet seed.