Established by Bill 53: Park Amendment Act 1995, 13 July 1995, encompassing Anne Vallee (Triangle Island) Ecological Reserve, Beresford Island Ecological Reserve, Lanz and Cox Islands Ecological Reserve, and Sartine Island Ecological Reserve; the whole containing 6,216 hectares more or less (2,139 hectares of upland and 4,076 hectares of foreshore). Name changed to Lanz and Cox Islands Park and area reduced [Anne Vallee (Triangle Island), Beresford Island and Sartine Island Ecological Reserves removed from the park] per Bill 17-2000: Protected Areas of British Columbia Act, 29 June 2000; the whole now containing 5,556 ha. more or less. (1,950 hectares of upland and 3,606 hectares of foreshore).
Source: BC place name cards, or correspondence to/from BC's Chief Geographer or BC Geographical Names Office