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FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



species rather than the mere presence or absence 

 of particular species. 



The wide geographical ranges of many coastal 

 birds are related to the fact that they are highly 

 migratory. A vast majority of the coastal species 

 move, in part at least, southward in winter be- 

 yond the boundaries of the United States. In 

 doing so, they are believed mainly to follow coast- 

 wise routes. Notable in this regard are the herons 

 and shorebirds. It is a common sight to see 

 flocks of each, in spring, flying in close formations 

 just beyond the surf, as thej' pass northward and 

 eastward along the Texas coast. On the eastern 

 side of the continent, the coastwise flights inev- 

 itably involve eventual passage over wide ex- 

 panses of open sea. While the path followed by 

 many birds doubtless leads across the Straits of 

 Florida and the Caribbean Sea, there is evidence 

 that others pass well out over the Gulf itself. 

 The occurrence of over 50 species of coastal birds, 

 in several cases regularly, on the Dry Tortugas 

 (Sprunt, 1951a, b) is evidence of over water 

 flights of considerable length. There are, in addi- 

 tion, specific records of coastal birds having been 

 seen on the open Gulf by ornithologists aboard 

 ships. Helmuth (1920) saw three great blue 

 herons approximately 100 miles off the Louisiana 

 coast on March 29, 1918, and five Louisiana herons 

 the following day about 180 miles off Alabama. 

 Frazar (1881) noted the ruddy turnstone 30 miles 

 beyond the mouth of the Mississippi River on 

 April 2, 1881, and Lowery (1946) recorded a single 

 great blue heron and seven long-billed curlews, in 

 the spring of 1945, 19 and 34 miles respectively, 

 off the same promontory. J. C. Howell (in Lowery, 

 1946) observed one green heron, two least bitterns, 

 and a single red-backed sandpiper on May 4, 

 1945, when his ship was plying between two points, 

 121 and 179 miles off Louisiana. Bullis and Lin- 

 coln (1952) describe the capture aboard ship of a 

 roseate spoonbill 38 miles off Louisiana, and 

 Packard (1947) states, without giving a date, that 

 he saw a wood ibis, among other species, at least 

 10 miles from land. A. H. Howell (1932) notes 

 of the black rail that "a migrant was taken on a 

 vessel, off Pensacola, March 10, 1885." That 

 coastal birds of several kinds, notably gulls, terns, 

 and ducks, forage out to sea is a well-known fact, 

 but there are so few specific records out on the 

 Gulf that we are unable to analyze at this time 



the frequency of such visitations in offshore wa- 

 ters or the distances involved. 



In this connection, it should be pointed out 

 that the greatest seabird colonies of the Gulf are on 

 islands. The majority of them lie within sight of 

 the mainland, but a few of the species we class as 

 coastal resort in part to the remoter islands where 

 they nest side by side with birds that we place in 

 the offshore category. Thus the royal tern is said 

 to breed on the Areas Keys; the Cabot tern on 

 Alacran Reef; and the laughing gull, in both places. 

 On May 20, 1912, on Alacran Reef, Kennedy 

 (1917) collected two specimens from a flock of 10 

 sandpipers, which he called "Baird's sandpiper 

 (Tringa fuscicollis)." This record is repeated in 

 the account of the Baird sandpiper in the Mexican 

 Check List, but according to J. D. Macdonald 

 (in litt.), of the British Museum, where the speci- 

 mens now repose, actually refers to the white- 

 rumped sandpiper. This is apparently the only 

 pul)lished observation of a transient migrant on 

 any of the offshore islands of the Campeche Bank. 



Just as these birds, for the most part, have a 

 wide geographic representation around the Gulf, 

 so too do they have a wide seasonal representa- 

 tion there. Among the entries in our coastal list 

 that are of regular annual occurrence, 56 have the 

 status of breeders, 49 occur as winter visitants, 

 and 8 are migrants not regularly represented in 

 summer or winter. There are no summer visitants 

 in the strict sense. In 77 cases — that is, in the 

 case of every species for which the annotation 

 does not explicitly state or definitely imply other- 

 wise — actual Gulf records are available for every 

 month of the year. Such gaps as do occur are 

 predominantly in summer (24 in the period from 

 June through August against 8 in the period from 

 December through February), demonstrating that 

 winter is the period of greater variety. This con- 

 trast gains increased force from the fact that sev- 

 eral of the species found in every month of sum- 

 mer seem never to be continuously present 

 throughout the season. It is not uncommon 

 among shorebirds for the last of the northbound 

 migrants to delay their departure until early June 

 and for the first of the southbound migrants to 

 return before July 31. 



One factor in the seasonal spread of the records 

 is the central position of the Gulf, and the essen- 

 tiall}' mild climate that goes with it. Only infre- 



