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Platte River Status: A common permanent resident. The Platte River Valley serves as an important wintering area for local birds and those from more northerly areas. Periods of peak numbers, indicative of migratory movements, occur during late February to late April, and early September to mid November.

Breeding Range: Locally common in the Platte River Valley west to Lake McConaughy, on the Eastern Plain, and the Dissected Plain regions; uncommon and local in the Sandhills and Western Plain regions.

Breeding Population: This species ranked 29th in abundance with an estimated mean population of 19,000 breeding pairs which made up 0.6% of the total breeding bird population in 1980.

Habitat: Highest mean breeding densities were in shelterbelt (84.0 pairs/km²), followed by river channel island (39.2 pairs/km²), lowland forest (10.0 pairs/km²), residential (3.6 pairs/km²), alfalfa (0.3 pairs/km²) and corn (0.1 pairs/km²). American goldfinch is closely allied with the seeds of various thistles (Circisum sp) as a food source. In our study area, thistles occur most commonly in roadsides, field edges and about areas of human habitation. Graber and Graber (1963) reported densities of 418 birds/km² from edge habitats and 240/km² from orchards in Illinois.

Effect of Habitat Alteration: American goldfinches have benefited from the alteration of natural habitats which has provided extensive areas of field edge for foraging, and both man-made (shelterbelt) and man-influenced (river channel island) habitats which provide suitable nesting sites.

Nesting Data: We found 1 nest at the Mormon Island Crane Meadows on 12 August 1983. The nest contained 1 fresh egg. By 16 August, 5 eggs were present and on 7 September, 5 young birds nearly able to fledge were in the nest. Mean clutch size among four nests in Lincoln County was 2.0 eggs during 18 June to 17 August. Kansas egg dates range from 20 June to 10 September (Johnsgard 1979), while North Dakota nest dates range from 2 July to 15 August.