Fig. 5.7 Small-scale promontories (tens of metres across the feature) on outer reef faces (northern
barrier reef of Palau shown) occur in many areas and are readily apparent to divers as a projection
of reef to seaward. Such small features are not known to be major locations for spawning aggregations, but few have been examined in detail
Fig. 5.8 Narrow atolls and islands often have acuminate projections of reef at both ends; sometimes
with spawning aggregation sites. ( a ) Little Cayman ( left ) and Cayman Brac were historically
known to have had Nassau grouper aggregations at both ends of the islands. Today an aggregation
is reported only on the western end of Little Cayman. Down-current eddies at the tips which might
help in retaining eggs and larvae in their vicinity (see Fig. 5.10a ). ( b ) Roatan, Bay Islands,
Honduras, is narrow with acuminate reefs at its tips with unverifi ed reports of spawning aggregations at the ends of this island. ( c ) Layang Layang atoll, South China Sea, had a single aggregation
of humphead wrasse ( Cheilinus undulatus ) at its western end ( white circle ), which is now fi shed
out. No aggregations are known from the eastern end of the atoll