the snowy plover ( Charadrius alexan- 

 drinus ) , Wilson's plover ( Charadrius 

 wilsonia ) , killdeer ( Charadrius 



vociferus ) , willet ( Catoptrophorus 

 semipalmatus ) and the blacknecked 

 stilt ( Himantopus mexicanus ). 



Woofenden and Schrieber (1973) 

 list 19 species of probing shore- 

 birds commonly observed in the Keys. 

 Oddly enough, snowy plovers, Ameri- 

 can oyster-catchers, and killdeer 

 were not observed. The most abun- 

 dant shorebirds, in order of decrea- 

 sing numbers, include short-billed 

 dowitcher ( Limnodromus griseus ), 

 semipalmated sandpiper ( Ereunetes 

 mauri ) , dunlin ( Erolia alpina ), 

 least sandpiper ( Erolia minutilla ), 

 and ruddy turnstone ( Arenaria 

 interpres ) . 



The most common and abundant 

 breeders in the floating and diving 

 water guild are the double crested 

 cormorant ( Phalacrocorax auritus ) 

 and the brown pelican ( Pelecanus 

 occidentalis ) . A total of 2,188 of 

 the double crested cormorant nests 

 and 298 brown pelican nests were 

 observed at 16 sites in the lower 

 Keys (Osborn and Custer 1978). The 

 combination of abundant fishing and 

 available breeding habitat favor 

 these two birds, here, as well as in 

 the upper Keys and Florida Bay. 

 Table 37 presents a comparison of 

 the abundance of breeding wading 

 birds and closely allied species in 

 the 4 major environments of the 

 study area. 



Robertson and Kushlan (1974) 

 list 7 aerially searching birds that 

 breed in the Florida Keys. Unfortu- 

 nately 2 of the 6 terns listed have 

 not been observed breeding since 

 1890. These two, the royal tern 

 ( Thalasseus maximus ) and the sand- 

 wich tern ( Thalasseus sandricensis ) , 

 both tend to feed far offshore, 

 primarily on fish. The noddy tern 

 (Anous stolidus), least tern (Sterna 



albifrins ) , roseate tern ( Sterna 

 douqallii ) , and sooty tern ( Sterna 

 fuscata ) are the more common breed- 

 ers, especially on the distal is- 

 lands. The laughing gull ( Larus 

 atrichia ) is the only that breeds 

 in the Keys. 



Other aerially searching birds 

 that may be found in the Keys as 

 transients or winter visitors 

 include the herring gull ( Larus 

 argentatus ) , ring-bill gull ( Larus 

 delawarensis ) , Bonapartes gull 



( Larus Philadelphia ), foresters tern 

 ( Sterna fosteri ), common tern ( Ster- 

 na hirundo ), Caspian tern ( Hydro- 

 pogne caspia ), and the belted king- 

 fisher ( Meqacryle alcyon ). 



The abundant marine life in 

 relatively shallow waters makes the 

 Keys a virtual haven for this guild 

 of birds. Trophically, the aerially 

 searching birds can be broken up 

 into two groups: (1) the gulls 



which depend upon not only fish but 

 insects, mollusks, and crustaceans 

 as well; the productive sea wrack 

 habitat which they share with prob- 

 ing shorebirds provides an added 

 diversity of food sources; and (2) 

 the terns which depend rather exclu- 

 sively upon fish. Some terns fish 

 close to shore, such as the least 

 and common terns, while others 

 (royal and sandwich) go farther off- 

 shore. The sooty tern, unlike other 

 terns does not dive but catches 

 surface fish in flight. The belted 

 kingfisher, a winter resident, tends 

 to remain close to the islands where 

 it feeds on fish as well as crus- 

 taceans and even some vegetation 

 when fishing is impossible (Sprunt 

 1954). 



Birds of prey in the Florida 

 Keys fall into two groups: (1) those 

 dependent primarily on the aquatic 

 food chain such as the osprey ( Pan- 

 dion haliaetus ), bald eagle ( Haliae- 

 tus lencocephalus ) , and magnificent 



217 



