BULLETIN FLORIDA STATE MUSEUM


 GENERAL DESCRIPTION OF THE ISLANDS AND THEIR AVIFAUNA

 The three Cayman Islands (Grand Cayman, Little Cayman, Cayman
Brac) lie in the northwestern Caribbean Sea where, as a group, their
remote position is rather extreme among the many West Indian islands.
Grand Cayman (1920'N,8120'W) is approximately 290 km (180 mi.)
south of Cuba, about the same distance northwest of Jamaica, and 480
km northeast of Honduras, the nearest point in Central America. Cay-
man Brac (19043'N,79050'W) is 89 km east of Grand Cayman and 8 km
east of Little Cayman. These three limestone islands are of similar
geological structure and represent the projecting peaks of the ancient
submarine Cayman Ridge extending from near British Honduras to Cuba
(Richards 1955). Steep-sided submarine slopes occur around the islands,
with a 100-fathom line lying only a few hundred meters offshore. Bart-
lett Deep, a 6,200 m trench, is found just south of Grand Cayman.
Further indications of the isolation of these islands are the many well-
marked animal species and subspecies that have been described from
them, including birds (Johnston et al. 1971), insects (Clench, H. 1964),
mollusks (Clench, W. 1964), and reptiles (Grant 1940).
 These islands are typically low and flat. Much of Grand Cayman
(185 km2) is less than five meters in elevation, although an east-west
forested ridge on its north side reaches 20 m in places. Low-lying la-
goons and inland swamps abound (Fig. 1). Chiefly because of a beauti-
ful beach of coral sand on its western side, most of the human popula-
 81I20 81"10




 WEST BAY NOR


19'20 R an
 RR




 GEORGETOWNlt EAST END



 Va LIMESTONE FOREST SCALE
 EE3 MANGROVE FOREST ,
 SPOND 3KM

FIGURE 1.-Map of Grand Cayman showing general distribution of major forest types
and ponds. P= pasturelands/clearings; R= residential areas.


Vol. 19, No. 5