Stewart Island — a case study for a marine protected area

The marine environment of Stewart Island is regarded as pristine and unmodified. Patersons Inlet is important from a scientific point of view while the inlet, adjacent coast and islands are popular with the recreational public. Marine farming in the sheltered embayments of the inlet has been considered.

The Department of Conservation is persuing the possibility of marine protected areas for Stewart Island. A general area was investigated which included Patersons Inlet, the adjacent coast and the offshore Muttonbird Islands. Rapid investigative techniques were used to gain preliminary information about the subtidal reef environment of this area.

Interesting changes in habitats occurred between the mid and outer sections of Patersons Inlet, the adjacent coast and the islands. Macrophytes occurred in high diversity and dominated the subtidal reefs in island, coastal and outer inlet areas. In the middle of the inlet, however, reefs were dominated by echinoderms. The studies of reef fish indicated that fish diversity was highest at the outer inlet and island sites. At mid inlet locations diversity was low while blue cod and spotty were numerically dominant. The densities of these species was low at the island sites.

The investigations indicated that, from a biological perspective, a marine protected area should incorporate the full range of marine habitats and associated species. Therefore, Patersons Inlet, the adjacent coast and the Muttonbird Islands should be considered in any proposal for a marine protected area.