Gladden Spit and Silk Cayes Marine Reserve, Marine reserve at Gladden Spit and Silk Cayes, Belize

The Gladden Spit and Silk Cayes Marine Reserve covers about 25,980 acres (10,510 ha) of Belize's Barrier Reef, 36 km off Placencia. Gladden Spit is a promontory at the southern tip of a sunken atoll whose shelf drops from about 40 m to 2,000 m within 10 km of the reef. North, Middle and South Silk Cayes lie just inside Queen Caye, and North Silk Caye holds a nesting colony of terns.

The reserve was declared on 18 May 2000 under Gazette No. 68/2000. In 2001 the whale shark feeding site was made a special protected zone, and tourism rules were drafted as whale shark tours increased. Since 2003 it has been divided into a general use zone, a no-take zone around the Silk Cayes, a conch restoration zone and a whale shark and reef-fish spawning aggregation conservation zone.

Since the 1920s, fishers have gathered at Gladden Spit to harvest mutton snapper and grouper during the ten-day spawning aggregation between March and June, and whale sharks arrive to feed on the eggs. The reserve is managed by the Southern Environmental Association, a community-based organisation, under the government's Fisheries Department.

The reserve can be accessed from Placencia, which serves as the main departure point for visits to the area. Travel to the site is best planned between March and June when marine activity is most visible.

This location represents the only known site worldwide where traditional fishing activities coincide with natural whale shark feeding patterns during fish spawning events.