American Oystercatcher Working Group


Author: Janell Brush (JB), Florida Fish and Wildlife Conservation Commission, Tallahassee, FL.

The Americas

Figure 1Breeding range. Figure 1. Along the Atlantic coast from Green Island, ME (Maine Dept Inland Fisheries and Wildlife, unpublished) south to St. Lucie Co., FL (Douglass and Clayton 2004); and on the Gulf Coast of Florida from Lee Co. north to Bay Co. (Douglass and Clayton 2004). A small population of breeding birds nest on coastal islands and occasionally along mainland shores in Alabama (R. Clay, pers. comm.). A 2006 breeding census conducted by the National Audubon Coastal Bird Conservation Program reported less than 20 pairs nesting on the barrier islands of Mississippi (Zdravkovic 2006). On off shore islands of e. Louisiana (S. Cardiff pers. comm.) and from Texas south to n. Veracruz, Mexico and on the n. coast of the Yucatan Peninsula (Howell and Webb 2007). Locally distributed permanent resident in the Caribbean on Andros Islands, and from Exuma south in the Bahamas (Prudenell-Bruce 1975, Buden 1992); also on offshore islands of Puerto Rico and the cays of the Virgin Islands (Raffaele 1989) and Martinique (D. McCrae pers. comm.). Occurrence variable; found sporadically in coastal areas of suitable habitat.

Resident on both coasts and offshore islands of Baja California from Isla San Geroimo south (Wilbur 1987), and along Pacific coast from Gulf of California south to Oaxaca, Mexico (Howell and Webb 2007). In Baja California their abundance is low and their distribution is marginal, occurring mainly in the islands Pacific Baja California, the majority of the breeding population in Northwest Mexico is distributed in the states of Sinaloa and Baja California Sur (Palacios et al. 2009). A few pairs resident on Los Coronados Is., just a few kilometers south of the Mexican border (Garrett and Dunn 1981). In Central America occurs locally along the Pacific coast of Costa Rica (breeding on Bolaños Island, Garrigues and Dean, 2007), and breeds in Panama south to Coiba Island and the Pearl Islands (Ridgely and Gwynne 1989). Also, regions of South America, south to S. Argentina (durnfordi) and Chile (pitaney). Also Galapagos Islands (galapagensis; Jehl 1985, Swash and Still 2005).

On the Atlantic coast, birds breed regularly, although in small numbers to New Hampshire and Maine and to New Brunswick and Nova Scotia (Mawhinney et al. 1999). On the Pacific coast, non-breeding strays have reached the Channel Islands off s. California (sometimes remaining for extended periods) and very rarely the California mainland (Garrett and Dunn 1981, B. Hoffman on LACo Birds listserve 2010).

Winter range. East Coast population winters regularly from Ocean Co., NJ, south; less commonly as far north as Long Island, NY and Connecticut, occasionally Massachusetts (Humphrey 1990, Veit and Petersen 1993). Wintering birds can be found throughout their range with largest winter concentrations on Southeast coast of New Jersey, the Eastern Shore of Virginia, the Bulls Bay region of South Carolina, The Altamaha River Delta in Georgia, and the Cedar Key area of Northwest Florida (Kain 1987; Post and Gauthreaux 1989; Sanders et al. 2004, Brown et al. 2005). Winter visitors have been recorded on both coasts of Mexico (Howell and Webb 2007), and migrants have been recorded on both coasts of Costa Rica (Stiles and Skutch 1989) as well as many Caribbean islands (Raffaele 2003). Populations on w. coast of Baja California and e. coast of Gulf of Mexico probably non-migratory. Strictly accidental inland, but has reached Lake Ontario, Idaho (Stephens and Stephens 1987) and the Salton Sea. Populations on w. coast of Baja California and e. coast of Gulf of Mexico probably non-migratory.

Outside The Americas

Not reported.

Historical Changes In Distribution

Historical status prior to 1900 unclear. Believed to have once nested along the entire Atlantic coast as far north as Labrador, but no substantiating records (Audubon 1835, Forbush 1912, Forbush 1925, Bent 1929, Griscom and Snyder 1955).

Virginia the northern limit of breeding range through early 1900s (Am. Ornithol. Union 1910, Post and Raynor 1964), although individuals observed then at Portland and Calais, ME (Forbush 1912, Bent 1929). Also, specimens collected near Boston Harbor (MA), in Marshfield, MA (in 1837), and on Monomoy I. (April 1885; Brewster 1885, Forbush 1912, 1925), and species reported to be common in the Boston Market (Forbush 1912). Thirteen records in Massachusetts from 1900-1955 (Bailey 1955, Griscom and Snyder 1955), more frequent from 1955 to 1969 (Viet and Petersen 1993).

Species known to have bred in New Jersey as early as 1812 (Leck 1984). Extirpated from New York in 1896 and New Jersey in 1897 (Griscom 1923). By 1900, considered rare or accidental north of Virginia (Cooke 1910, Bailey 1913) where extirpation was predicted (Bailey 1913, Forbush and May 1939). At the same time becoming rare in S. Carolina (Bent 1929), Georgia (Erichsen 1921), and on the Gulf coasts of Florida (Sprunt 1954, Rodgers et al. 1996) and Texas (Forbush 1912).

Virginia was the northern edge of the breeding limit during the first 3 decades of the 20th century. By 1939, breeding range had expanded north in to the Maryland portion of Assateague I. (Stewart and Robbins 1958). First nesting this century in New Jersey in 1947 (Leck 1984), in New York in 1957 (Post 1961, Post and Raynor 1964). By 1952 bred at 3 locations in Worcester Co., MD (Stewart and Robbins 1958). In New Jersey, 11 nests located in 1954 (Leck 1984). By the early 1960s a regular breeder in New Jersey (Kramer 1948, Post and Raynor 1964). By 1963 nested in New York, but little increase and gulls and human disturbance thought to be a serious threat (Post and Raynor 1964). By the early 1970s, however, bred commonly on dredge spoil islands of Long Island, NY (Zaradusky 1985, Lauro and Burger 1989) increase in numbers of its major prey, Mytilis mussels, as pollution of waters around Long Island abated, may have encouraged colonization (Andrle and Carroll 1988). Early occurrences in Rhode Island in 1938 and 1954, after southern storms; later, transients seen there in 1968, 1969, and 1970; first Rhode Island breeding on Block I. in 1976 (J.E.Myers pers.comm.). First bred in Connecticut in 1980 (N. Proctor pers. comm.). In 1997, observed nesting on Green Island, ME and another pair was observed on Clark’s Harbour on Cape Sable Island, Nova Scotia (Mawinney et al. 1999).

The first Massachusetts nesting occurred on Martha’s Vinyard in 1969 (Finch 1970). By 1970 additional pairs nested to the north on Monomoy I. By 1979 at least 18 pairs breeding in the state, 4 pairs on Monomoy; in 1984 an estimated 42 breeding pairs in the state, with 20 pairs on Monomoy in 1986 (RH, Veit and Petersen 1993). From 1987 to 1993 additional sightings north of Monomoy, to Logan International Airport (Boston, MA; RH and P. Stevens pers. comm., N. Smith pers. comm.).

West Coast Population (H.p.frazeri) considered common in the Gulf of California, locally common on the mainland coasts of Sonora and Sinaloa (Mexico), and spottily distributed south to the Isthmus of Tehuantepec (Jehl 1985). Further south it was (and continues to be) rare (Griscom 1933, Slud 1964, Jehl 1985). Frazeri also occurs on the Tres Marias but not on the Revillagigedos Islands (Brattstrom and Howell 1956, Jehl 1985). Late in the 19th century, both American Black Oystercatcher and American Oystercatcher were seen commonly on the west coast of n.Baja, but by 1969 only small numbers of Black Oystercatchers remained, with but a few scattered sightings in the 1980s (Jehl 1985). Decline likely due to intensive collecting and/or disturbance from permanent fishing camps. Midway down Baja, more frazeri than bachmani, but numbers on all islands are small (e.g., ≥10 pairs frazeri on San Benitos Island.; Jehl 1985). The San Roque and Asuncion Islands supported large populations (predominantly frazeri but also hybrids) in the late 1800s (11 birds collected in 1 d on Asuncion, 20 in 1 d on San Roque Island), but by 1927 only a few pairs remained and by 1974 none (Jehl 1985). In sw. Baja California, probably small numbers on mainland beaches and coastal lagoons, but no reliable estimates (Jehl 1985). In San Ignacio Lagoon, about 100 frazeri in a single flock in winter (W.T. Everett in Jehl 1985).

Distribution in Bahamas scattered; in West Indies rare (Bond 1971, , Downer and Sutton 1990, Raffaele 2003, probably at least since 1920s (Wetmore and Swails 1931, Barbour 1943, Garrido and Montana 1975). Very rare winter resident in Cuba (Garrido and Kirckconnell 2000).

Fossil History

There are no fossil or prehistoric records for this species. However, there are two early Piocene, late Hemphillian (North American Land Mammal Age, 4.5 to 5.2 million years before present) records of importance. Haematopus sulcatus (Brokorb 1955; revised by Olson and Steadman 1979) is from the Bone Valley Formation (Palmetto Fauna), Florida and it is the oldest fossil species of oystercatcher. Also, there is a record from the Yorktown Formation at Lee Creek, NC, of Haematopus sp. (Olson and Steadman 1979).