10 SEA-BIRDS 



vegetation, with coastal mangroves, but also many sandy islets and 

 bars and real coral reefs. Though the Guiana coast was too muddy 

 to support coral reefs, these are found fringing the islands north of 

 Venezuela, such as Curasao. There are also many reefs along the 

 western shore of the Caribbean, particularly at the corner of Nicaragua 

 and Honduras, at the end of the shallow Mosquito Bank. Throughout 

 the West Indies the distribution of sea-birds is linked primarily with 

 available food, but that of the breeding adults probably also with 

 available nesting-sites. Islets where there are exposures of rock or 

 sand are much favoured, but some species as we have seen, including 

 the red-footed booby, the brown pelican, the bigua cormorant, the 

 darter Anhinga anhinga, and some terns, nest in trees. One very rare 

 petrel Pterodroma hasitata (p. 76) nests above the tree-line on some of 

 the West Indian islands, among the rocks of steep mountains. 



A typical sea-bird islet in the West Indies is Desecheo, described 

 by Alexander Wetmore. This lies in the hot dry zone west of Porto 

 Rico. It is a rocky islet with cliffs and a gravel beach, and a thin 

 top-soil covered with a dense thicket of cacti and the curious West 

 Indian birch. Here brown boobies nested on the ground among the 

 thickets and floundered through the prickly pear and cactus. Sooty 

 terns nested on ledges, on shelves on the limestone cliffs, and B. S. 

 Bowdish found a few bridled terns Sterna anaetheta, nesting on flat 

 ledges. This species also breeds on the little islets or cays of the Barrier 

 Reef south of Jamaica, among the broken coral rock and the man- 

 groves. 



North of the Antilles the low-lying British islands of the Bahamas 

 occupy a large area of the west Atlantic. The blue Atlantic beats 

 directly against steep east-facing limestone cliffs, while to the west 

 there are shelving beaches. Many of these islands are covered with 

 cacti, and the sea-grape Coccolobis, which forms low, thick vegetation 

 in which brown boobies nest, scraping slight hollows in the ground 

 and lining them with grass. In some Bahamas the man-o'-war bird 

 builds its nest quite on top of the prickly pears, though more normally 

 on the mangroves in the swamps, together with brown pelicans and 

 the double-crested cormorant of Florida Phalacrocorax auritus floridanus. 

 Upon the more exposed sandspits in the Bahamas several kinds of 

 tern breed, including the gull-billed tern, the little tern Sterna 

 albifrons, the roseate tern S. dougallii, Cabot's tern Thalasseus 

 sandvicensis , and the sooty tern. 



The coast of the Gulf of Mexico is low-lying, with coral reefs 



