Enemies.—Prowling mammals, the enemies of ground-nesting birds, and predatory hawks are a danger to the bird. In its relation to the cowbird, Friedmann (1929) reports the bird as “a very uncommon victim.” He says: “I have only six definite records, but the species is listed as a molothrine victim by Bendire and by Short. As many as four eggs of the Cowbird have been found in a single nest of this Warbler.”
Fall and winter.—We lose sight of the goldenwing early in the season. Silent amid the dense foliage of July and August, the bird is rarely seen. During the years between 1907 and 1920, when I kept a daily record of birds seen, I met it only four times in August and only twice in September, the latest September 12.
Dr. Alexander F. Skutch sends to A. C. Bent the following account of the bird in its winter quarters: “I am familiar with the golden-winged warbler in its winter home only in Costa Rica. In this country it winters on the Caribbean slope from the lowlands up to about 6,000 feet above sea-level, and on the Pacific slope at least in the region between 2,000 and 4,000 feet. While it appears to be nowhere abundant, I found it most numerous at Vara Blanca, on the northern slope of the Cordillera Central at an elevation of about 5,500 feet. Here on one day—November 2, 1937—I saw three individuals, the greatest number I have ever recorded. This is a region of dense vegetation, subject to much cloudiness and long-continued, often violent rainstorms—one of the wettest districts of all Central America. Most of the published records are from this generally wet side of the country. Yet the bird winters sparingly in the Basin of El General on the Pacific slope, which during the first 3 months of the year may be nearly rainless. While in the Tropics, it appears never to associate with others of its own kind, but at times may roam about with mixed flocks of other small birds. It may forage among low, fairly dense, second-growth thickets, or among the tangled vegetation at the forest’s edge, or at times in the forest itself, or in groves of tall trees, high above the ground. It investigates the curled dead leaves caught up among the branches, and devours such small creatures as it finds lurking in their folds. I have not heard it sing while in its winter home.
“In Costa Rica, it appears to arrive late and to depart early, not having been recorded before September 15, nor later than April 9. Early dates of fall arrival are: Costa Rica—San José (Cherrie), September 15 and October 2; La Hondura (Carriker), September 21; Basin of El General, October 18, 1936; Vara Blanca, October 5, 1937.
“Late dates of spring departure are: Costa Rica—Basin of El General, April 8, 1936, April 7, 1937, March 30, 1939, and April 9, 1943; Vara Blanca, April 9, 1938; Guápiles (Carriker), March 30.”
DISTRIBUTION
Range.—Eastern United States to northwestern South America.
Breeding range.—The golden-winged warbler breeds north to central Minnesota (Detroit Lakes, Onamia, and Cambridge); central Wisconsin (St. Croix Falls, New London, and Shiocton); northern peninsula or Michigan (McMillan and Mackinac Island); southern Michigan (Kalamazoo, Locke, and Detroit); southern Ontario (London and Port Rowan, has occurred north to Collingwood and Bowmanville); central New York (Medina, Rochester, and Waterford); central Vermont (Rutland), and northern Massachusetts (Winchendon, Newton, and Lynn). It has been found in summer and may possibly breed in southern New Hampshire (Concord and Durham); and southwestern Maine (Emery Mills and Sandford). East to eastern Massachusetts (Lynn, Boston, and Rehoboth); southern Connecticut (New Haven and Bridgeport); northern New Jersey (Morristown); central Pennsylvania (near State College); and south through the mountains to western North Carolina (Weaverville, Waynesville, and Highlands); northwestern South Carolina (Caesars Head and Highlow Gap); and northern Georgia (Young Harris, Margret, and Oglethorpe Mountain). South to northern Georgia (Oglethorpe Mountain and Rising Faun); central Tennessee (Maryland); northern Ohio (Steuben, Port Clinton, and Wauseon); northern Indiana (Waterloo); and northern Illinois (Riverside). West to northern Illinois (Riverside); central and western Wisconsin (Baraboo Bluffs and Durand); and central Minnesota (Minneapolis, Elk River, and Detroit Lakes). It has been noted in summer, or in migration, west to St. Louis, Mo.; Lake Quivira and Lawrence, Kans.; and Omaha, Nebr.
Winter range.—In winter the golden-winged warbler is found north to central Guatemala (Cobán); and northern Honduras (Lancetilla); casually or in migration to the Yucatán Peninsula (Campeche and Mérida). East to Honduras (Lancetilla); eastern Nicaragua (Escondido River); Costa Rica (Guápiles and Guayabo); central Panamá (Lion Hill, Canal Zone); and central Colombia (Santa Marta region, Bogotá, and Villavicencio); rare or accidental in western Venezuela (Mérida). South to central Colombia (Villavicencio and El Eden). West to northwestern Colombia (El Eden, Medellín, and Antioquia); western Panamá (Chiriquí); Costa Rica (El General and Nicoya); and central Guatemala (Cobán).