Marine parks are managed by the Department of Parks and Wildlife on behalf of the people of Western Australia. They cater for multiple use and have many different zones (areas of ocean set aside for a particular purpose) so you can enjoy all sorts of marine activities such as:
You can usually go fishing outside designated sanctuary zones, as long as you follow size and bag limits set by the fisheries department (check what they are first). Some different types of fishing may be restricted in different zones. For instance, commercial fishing is not allowed in recreation zones and rock lobster fishing is not allowed in some special purpose zones. Each marine park in Western Australia has its own zoning scheme, so before you fish in a marine park 'Know Your Zones' and find out the rules for each zone.
