By Margaret Cotrufo, Assistant Librarian
The brightly colored yellow and black American Goldfinches (Carduelis tristis) have been busy nesting at Prairie Ridge. Yes, nesting this late in the summer! The Goldfinch is one of the last members of the passerine family to begin building a nest in North Carolina. One reason for this late nesting seems to depend on the flowering of the thistle plant. The downy material from the seeds of thistle and milkweed plants is used as a lining for the nest, while the seeds provide a high protein food for the nestlings.
Mated pairs of goldfinches choose a suitable nest site, often found about 10-feet from the ground in trees or shrubs in open areas such as on the outskirts of fields. The nest is an open cup of rootlets and plant fibers lined with plant down, often woven so tightly that it can hold water.
Many seed-eating song birds rely on high protein foods such as insects to feed their young. Unlike other seed-eating birds Goldfinches are so strict with their vegetarian diet that nest parasite species such as Brown-headed Cowbirds (Molothus ater) seldom survive on the all-seed diet that goldfinches feed their young.
As summer comes to an end be sure to look for evidence of these late nesting birds.
Find out more about the natural happenings at Prairie Ridge at our What Time Is It In Nature Archive.