Smithsonian Institution story on the small boa constrictors of the Snake Cayes in Belize.
"...Among the boas there is an island-dwelling form in Belize that is the subject of interest to conservationists, ecologists and, lately, behavioral biologists. This is the miniature boa of Snake Cayes, a group of islands off the coast of southern Belize. When I say “miniature” I mean that they range in length from 30 cm to about 2 meters (1 to 6 feet). This is small compared to the mainland boas of the same species, which can reach 4 meters (13 feet) in length..."