Distribution

Breeding Range

In e. U.S., almost exclusively coastal, nesting on barrier beaches, shell banks, spoil islands, and salt marshes (occasionally on mainland) from Massachusetts (small numbers) and Long Island, NY, along the Atlantic and Gulf coasts to s. Mexico (Tabasco) with isolated colonies in n. Yucatan (Fig. 1) (see details in Clapp et al. 1983, Howell and Webb in press). In Florida, frequently occurs inland, sometimes in large numbers; has bred inland near Belle Grande in s.-central Florida (Robertson and Woolfenden 1992) and at Okeechobee, FL (Langridge and Hunter 1986). Has bred in Connecticut (Zeranski and Baptist 1990).

Western population breeds from s. California (inland at Salton Sea, along coasts in San Diego and Orange counties) south to Nayarit, Mexico (Am. Ornithol. Union 1983, G. McCaskie pers. comm.). Suspected of breeding in small numbers in s. San Francisco Bay, based on migrating family groups seen in Monterey area (Roberson 1985), although banded birds in Santa Barbara are known to come north from San Diego and the Salton Sea. Reported breeding in Colima (Howell and Webb in press). Uncommon permanent resident in Oaxaca (Binford 1989). Recorded in Baja California only since 1979; a potential breeder there (Wilbur 1986).

Brown or sooty-tailed race, R. n. cinerascens, breeds in w. Ecuador and on large rivers in ne. South America (as far up the Amazon River as Leticia, Colombia) (Hilty et al. 1986), and wanders regularly to Chile (sometimes to the Straits of Magellan) and Trinidad, occasionally to Panama (1 record Ridgely and Gwynne 1989) and Costa Rica (Stiles and Skutch 1989), rarely to Grenada. White-tailed race, R. n. intercedens, breeds from Maranhão in e. Brazil to central Argentina (s. Buenos Aires Province), and possibly to Santa Cruz (Murphy 1936, Blake 1977).

Winter Range

Persists on Long Island, NY, into Dec, but rarely overwinters. Otherwise winters irregularly in small numbers from N. Carolina and commonly from S. Carolina (Post and Gauthreaux 1989) along the Gulf Coast (Clapp et al. 1983) south rarely to Panama and accidentally to Venezuela (Meyer de Schauensee et al. 1978); also on the Pacific Coast commonly to Costa Rica (Stiles and Skutch 1989); very rarely to Panama (Blake 1977, Ridgely and Gwynne 1989). Most or all birds in Netherlands Antilles are referable to R. n. cinerascens (Voous 1983). Rare and irregular in the West Indies south to Guadeloupe. Migrates mainly along coast. Casual inland in the U.S. and Mexican plateau (Williams 1982). Post-breeding or storm-driven wanderers casual in the Canadian Maritimes (Godfrey 1979) and to central California. During the years 1962–1972, reported at 65 of 1,282 Christmas Bird Count sites: highest concentrations in e. Florida and the Everglades, corresponding with the 10o C minimum Jan temperature isocline (Root 1988). Same pattern prevailed 1973–1977, with peak estimates of 1,344/10 party/h near Jacksonville, FL (Bystrak 1974).

No records (e.g., none for Britain and Europe) (Alström and Colston 1991).

The explorer, Samuel de Champlain, described skimmers on Cape Cod, MA, in July 1605 (Purdie 1882), too early in the year for postbreeding wanderers; species apparently nested also at Muskeget I., se. Massachusetts until 1830, but colonies probably eliminated by eggers (Forbush 1925). The hunting and millinery trade that extirpated herons, egrets, and terns from much of their range affected skimmers as well by eliminating their preferred nesting associates. Skimmers were not sought directly for feathers or food, although their eggs were prized (Forbush 1925). First recent breeding record on Cape Cod in 1956 (Hill 1965), although postbreeding groups of adults and immatures seen as early as 1936 (Griscom 1937). Has increased in Connecticut since 1960, but still few breeding records (Zeranski and Baptist 1990).

From about 1850 until the 1920s, when postbreeding wandering from the recovering s. New Jersey colonies became common, species only a scarce vagrant to Long Island, NY (Griscom 1923). First recent New York breeding record at Gilgo, Long Island in 1934, with 40 pairs breeding regularly by 1940 (Cruickshank 1942). New York population increased dramatically in 1960s and has since stabilized (Bull 1974) (MG, JB unpubl. data).

Common breeder in New Jersey in early 1800s, but apparently nearly absent between 1895 and 1915, recovering slowly thereafter (Stone 1937) to 2,000+ pairs by the 1970s (JB unpubl. data). Declined on Cobb’s Island, VA, from thousands in 1902 to 300 in 1909 (Howell 1911). A 1992 survey of the Virginia barrier islands produced a total of 2,422; an 18-yr survey mean through 1992 was 5,422 (Williams et al. 1993). Texas population variously reported as slowly declining (White et al. 1984) or stable (Custer and Mitchell 1987).

Unrecorded in California prior to 1962. At Salton Sea, first recorded in 1968 and began nesting in 1972. At San Diego, CA, first recorded in 1971, began nesting in 1976 (Garrett and Dunn 1981). Has nested at several sites on coast of Orange County (including Bolsa Chica Lagoon and Upper Newport Bay) since 1985. In 1986, one pair nested inland and well to the north in Kings Co., CA (Erickson et al. 1986). Murphy (1936) reported a dramatic decrease in populations along Pacific Coast of South America in the early 20th century.

Known from Tertiary strata of Patagonia (Pearson 1936).