Bokak Atoll - Fauna

Fauna

The atoll supports a large population of sea and shorebirds, with up to 26 species present. Species breeding during 1988 included the brown booby, red-footed booby, Great Frigatebird, Red-tailed Tropicbird, Sooty Tern, White Tern, Brown Noddy, and possibly the Reef Heron. Migratory birds present included the bristle-thighed curlew, turnstone, wandering tattler, golden plover, and the sanderling. The densest bird populations are on three islets to the north of Sibylla: North (Kita), Kamwome and an unnamed islet. Bokak is the only known breeding ground of Christmas Shearwater and possibly Bulwer's petrel.

Terrestrial species includes the Polynesian rat on Sibylla. The more aggressive black rat appears to be absent, despite wrecked fishing vessels on the eastern and north eastern reefs. The Snake-eyed Skink and large hermit crabs are common.

In general, the aquatic fauna population is healthy, but of low diversity, possibly due to the atoll's isolation. Researchers have not seen any marine turtles, but Polynesian custom regarding harvesting assumed their presence. Examples of the giant clam family Tridacnidae are very abundant, except for the largest giant clam T. gigas. Smaller bivalves were present, but few Mollusks. The reef fish are primarily emperor breams, parrotfish, and red snappers. Also present are moray eel and grey reef shark. Approximately 100 stony coral species and two soft coral species are present.