Distribution

Breeding Range

Northeastern population breeds at relatively few, strictly coastal locations (Fig. 1). Since 1977, between Québec (Is. Madeleines) and New York (Long I.), about 80% of the population has bred at 2 large (>1,000 pairs) colonies (Great Gull I., NY; and Bird I., MA); remainder of northeastern population breeds in about 15–20 smaller colonies (see Appendix 1). Isolated recent records from New Jersey (formerly a very rare breeder; JB) and N. Carolina (once).

Caribbean population (see Fig. 2) breeds from w. Florida Keys, Cuba, Hispaniola, Jamaica, Puerto Rico, Virgin Is., and Bahamas (many islands) through Lesser Antilles (St.-Barthélemy, Antigua, Guadeloupe, Martinique, St. Lucia [probable], Grenadines; Evans 1990) to islands off Central America (Belize), and from Netherlands Antilles and islets off Venezuela east to Tobago. In Florida Keys, described as “breeding summer resident on the Dry Tortugas, Key West, and occasionally certain other Florida Keys” (Stevenson and Anderson 1994: 295). Not known to breed in Mexico (Howell and Webb 1995), or at any inland sites; very few inland records in any season.

Winter Range

Poorly known. Rare north of South America. Sight records from s. Florida rejected by Stevenson and Anderson (1994). Most northeastern birds probably winter on coast of South America; some possibly at sea (Nisbet 1984). Recently found wintering in large aggregations with Common Terns at Mangue Seco (border of Sergipe and Bahia, Brazil; Hays et al. 1997 .). Two band recoveries from Pacific coast of Colombia (Hays 1971, Nisbet 1984). Many records from West Indies and Guyana, mainly of migrants (Nisbet 1984); few in winter (Hays et al. 1997). Southernmost record in s. Bahia, Brazil, at 18°S in Mar 1995 (Hays et al. 1997).

Few data on winter distribution of Caribbean population. Some mingle with northeastern birds on coast of Brazil (H. Hays pers. comm.). Birds banded as young in U.S. Virgin Is. were recovered in Guyana in Sep–Oct (Nisbet 1984).

Breeding Range

In Europe, from Britain and Ireland to Azores and Canaries (Cramp 1985). Small, endangered population in South Africa (Cape Province). Indian Ocean from Seychelles, Kenya and Tanzania (relatively large colonies; Urban et al. 1986), Madagascar, and Oman to Burma and w. Australia. South China Sea and w. Pacific Ocean from s. Japan and Thailand to Java Sea, n. and e. Australia (Great Barrier Reef) to Loyalty Is., possibly Fiji (Higgins and Davies 1996). Few breeding sites known in Indonesia and Malaysia.

Winter Range

Most populations migratory. For Palearctic populations, poorly known, but range includes w. Africa from Gambia to Cameroons, e. Africa off Kenya, and Timor, Java Sea, and Coral Sea (Serventy et al. 1971, Glutz von Blotzheim and Bauer 1982, Gochfeld 1983, Cramp 1985, Higgins and Davies 1996).

Like most terns, disappeared from most North American coastal breeding sites in nineteenth century because of market gunning and millinery trade; recovered and spread along Atlantic Coast in mid-twentieth century because of protection. Declined in 1960s and 1970s (Nisbet 1980), apparently stabilizing thereafter; declined in Nova Scotia after 1980 and on w. Long I., NY, after 1992, but increased in Maine (see Appendix 1).

Formerly bred in Bermuda (until 1890), Virginia (to 1930s), New Jersey (maximum 10 pairs in 1970s, only 1 in 1980, none since). Formerly more widespread in Europe and w. Mediterranean. Most tropical populations poorly documented, but a recent survey suggests few major changes since 1930s (A. del Nevo pers. comm.).

No information.