Mount Dutton Bay is a quiet arm of the Coffin Bay inlet system, and its jetty stands beside a heritage-listed woolshed built in the 1870s, when wool was shipped out from here by ketch. The Marine Life Society describes the Coffin Bay area as picturesque, very shallow and very sheltered, with rocky reefs, nearby islands and a wealth of marine life. At Mount Dutton Bay the water under and around the jetty is shallow – typically 1-3 m at high tide – over dense seagrass meadows that are among the most productive nursery habitats on the west coast.

Snorkellers see King George whiting, garfish, juvenile snapper, leatherjackets, blue swimmer crabs, stingarees and pipefish, with seahorses possible on the piles. Dolphins are common in the inlets, and the Coffin Bay area is famous for its oyster farms. This is a relaxed snorkel for visitors staying at the woolshed or exploring Coffin Bay, not a destination scuba dive.

Coffin Bay township and the national park offer more varied diving, and Coffin Bay Scuba Co. can recommend sites based on the day's conditions.

From Port Lincoln drive north-west on the Flinders Highway towards Coffin Bay (about 50 km), then follow signs to Mount Dutton Bay (about 20 km from Coffin Bay township) on sealed and gravel roads. The jetty is beside the historic woolshed (now accommodation and a museum). Park near the woolshed and walk a few metres to the water.

The bay is very shallow – enter near high tide.

The west coast of Eyre Peninsula faces the Great Australian Bight and receives almost constant south-westerly Southern Ocean swell; open-coast sites need swell under about 1.5 m and are only diveable a handful of days a month, usually after several days of northerly or easterly winds, which blow offshore. The large sheltered bays (Coffin Bay, Waterloo Bay, Venus Bay, Baird Bay, Streaky Bay, Denial Bay) are protected from swell and can be dived in most conditions except strong onshore winds. Summer brings strong afternoon south-easterly sea breezes; winter brings cold fronts with big swell but also calm, clear spells.

Water is cool: about 14-15°C in winter and 17-21°C in summer. Mount Dutton Bay is deep inside the Coffin Bay inlet system and completely sheltered from swell; only strong winds and low tide spoil it.

At high tide snorkel or dive along the jetty and over the adjacent seagrass, looking for pipefish, seahorses and juvenile fish.

No regular dive operator at the jetty; Coffin Bay Scuba Co. operates in the Coffin Bay area and can advise on local sites.