Multispecies fisheries associated with coral reefs are difficult to manage. However, the use of marine protected areas has been proposed as an alternative way of managing such fisheries. It is thought by guarding stocks from exploitation in marine protected areas there will be an increase in the number and size of females, and as a result, an increase in egg production. The additional larvae produced by these improvements to breeding stock should be available to inhabit areas open to fishing. The project involves monitoring the abundance and size of commercially valuable sea cucumbers, trochus, giant clams and green snail at and around the Arnarvon Islands, before (Phase 1) and after (Phase 2) the declaration of the Marine Conservation Area. In addition to the data collected for the monitoring program, data will be collected on fish assemblages, coral cover, and topographic complexity for entry into ICLARMs REEFBASE.