The male Rose-breasted Grosbeak is conspicuous, not only because of his bright coloring, but also because of his singing. He will sing throughout his courtship with the female, during nest building and even while sitting on the nest (when incubating the eggs and brooding the young). The female will sing while building the nest as well. Traces of old nests are sometimes seen quite near the new nests, implying that this bird may return to the same area for nesting year after year.

Species Characteristics:
Length: 7.25 in to 8in (18.4 cm to 20.3 cm)
Physical characteristics: The male in his breeding-season plumage is quite striking. His head and back are black; his wings and tail are black with large white patches. His underparts are white, aside from a bright red breast patch. The female has grayish-brown upperparts, and a whitish breast and belly with heavy dark streaking. There is a buff crown stripe. Both sexes have a large, conical bill and bright pink linings at the base of the undersides of their wings.
Voice:
Song is a melodic warble similar to the song of the American Robin, but steadier and richer in tone.

Breeding habitat:
This species prefers to breed in deciduous forest, often in second-growth, scrubby or shrubby woodland, by streams or forest edges.

Mating system:
Monogamous; 1 - 2 broods are produced per year.

Nest:
The nest is a loosely built cup made from twigs and other plant material, and lined with rootlets and hair. The male may choose the nesting site, but both sexes participate in building the nest.

Eggs:
3 - 6 eggs, which are pale green, blue or bluish-green in color, are laid in a clutch. They are marked with browns or purples and are usually wreathed. 25mm (1.0''). Chick development The eggs are incubated by both sexes. They hatch in 13 to 14 days. The chicks are altricial at hatching and are cared for by the male and female. They will leave the nest after 9 - 12 days. They continue to be cared for by the parents for a few more weeks. If the female is starting a second brood, the male will care for the fledged young.

Diet:
The diet consists of insects, seeds and some fruits and flowers. This species gleans while hovering or will glean on the ground. The female tends to forage higher off the ground than the male.

Parasites
An undescribed species of feather mite of the genus Pterodectes (Proctophyllodidae) and the louse Brueelia pallidula (Piaget) (Philopteridae) were collected from grosbeaks caught at Purchase Knob, North Carolina, during the summers of 2005 and 2006 (Reeves et al. 2007).

Parasites of the genus Leucocytozoon, a parasitic protozoan that circulates in the host?s blood and infects internal organs, were visually confirmed in a blood sample from a grosbeak caught at Gregory Bald on the state line in 2001 (det. P. E. Super). Avian pox-like symptoms have been observed in park birds from Purchase Knob.

Conservation Biology:

Breeding: The Rose-breasted Grosbeak breeds from Northern British Columbia, east across southeastern Canada, and south into the northeastern corner of the United States. Its range dips down into the mountains of Georgia.
Winter: This bird is a neotropical migrant and winters from southern Mexico to Ecuador and Venezuela in South America.

The Rose-breasted Grosbeak is a common breeding bird species in the Park. This species is absent during the winter months, but is common during fall and summer migration. It is more common on the North Carolina side of the Park than on the Tennessee side of the Park, and is often found in lower - middle elevation forests in the Park.
A survey of breeding birds in the Park, performed from 1996-1999, ranked Rose-breasted Grosbeak as the 36th most common species out of 113 species observed during the breeding season. Estimates from this survey indicate that overall Rose-breasted Grosbeak density in the Park during the breeding season is approximately 0.043 pairs/hectare. Densities peak between 2,000 - 3,000 feet and then decline rapidly to low densities above 4,000 feet.
The population of this species is declining in some areas, particularly in the East.
The Rose-breasted Grosbeak is also a common cowbird host.

References:

Alsop, F. J. III. 1991. Birds Of The Smokies. Great Smoky Mountains History Association, Gatlinburg, Tennessee.

Committee on Classification and Nomenclature of the American Ornithologists' Union. 2000. Forty-second supplement to the American Ornithologists' Union Check-list of North American Birds. The Auk 117: 847-858.

Committee on Classification and Nomenclature of the American Ornithologists' Union. 2002. Forty-third supplement to the American Ornithologists' Union Check-list of North American Birds. The Auk 119: 897-906.

Committee on Classification and Nomenclature of the American Ornithologists' Union. 1998. Check-list of North American Birds: the Species of Birds of North America from the Arctic through Panama, including the West Indies and Hawaiian Islands, 7th ed

Ehrlich, P. R., D. S. Dobkin, and D. Wheye. 1988. The Birder's Handbook: a Field Guide to the Natural History of North American Birds. Simon and Schuster, Inc., New York.

Elphick, C., J. B. Dunning, Jr., and D. A. Sibley, eds. 2001. The Sibley Guide to Bird Life and Behavior. Alfred A. Knopf, New York.

Gough, G. A., Sauer, J. R., Iliff, M. Patuxent Bird Identification Infocenter. 1998. Version 97.1. Patuxent Wildlife Research Center, Laurel, MD. http://www.mbr-pwrc.usgs.gov/id/framlst/infocenter.html.

Reeves, W. K., L. A. Durden, C. M. Ritzi, K. R. Beckham, P. E. Super, and B. M. O?Connor. 2007. Ectoparasites and other ectosymbiotic arthropods of vertebrates in the Great Smoky Mountains National Park, USA. Zootaxa.

Sibley, D. A. 2000. The Sibley Guide to Birds. Alfred A. Knopf, New York.

Stupka, A. 1963. Notes on the Birds of the Great Smoky Mountains National Park. University of Tennessee Press.