White Rock is the bird-covered rock at the northern end of Welcome Bay on Fitzroy Island, and the reef around it and along the north coast beyond is the island's most interesting shore dive. Wikipedia's account of the national park calls the northern reef marker in Welcome Bay Bird Rock; snorkel guides call it White Rock, from the guano, and it is visible from the ferry as you arrive. The water is deeper here than off the main beach, and snorkel guides describe colourful tropical fish, turtles, rays and reef sharks around the rock, with schools of fish, rays, turtles and good coral beyond it along the north coast, where marker buoys serve as turning points.

They rate it an advanced snorkel because there is no quick exit to shore once you are around the rock, and that caution applies to divers too: plan a there-and-back dive with enough gas and energy to return against any current. For certified divers the reef slopes from the rock into water deep enough for a proper dive, typically 5-12 m, with hard and soft corals and more fish than inside the bay. Visibility, as elsewhere on Fitzroy, is modest and depends on recent weather, though guides note it improves as the tide drops.

Access is on foot along the beach at low tide or by the track past the campground and turtle rehabilitation centre at high tide. The island dive shop can guide the dive, and a Snorkel Safari boat tour reaches the northern reefs without the long swim. It suits Open Water divers with some shore-diving experience.

Ferry from the Reef Fleet Terminal, Cairns, to the Fitzroy Island jetty (about 45 minutes). At low tide walk north along the sand from the main beach to the far end of Welcome Bay; at high tide take the track past the campground and turtle rehabilitation centre. White Rock, covered in birds, is visible from the ferry.

Enter from the beach near the rock. There is no quick exit once you round the rock onto the north coast, so plan to return the way you came; the dive shop runs guided dives and the Snorkel Safari boat tour reaches the northern reefs without the long swim.

Fitzroy's western side, where Welcome Bay and Nudey Beach lie, is sheltered from the prevailing south-east trade winds, so shore diving and snorkelling are possible on most days; strong northerlies or north-westerlies make the bay choppy. Visibility is typically 5-15 m and falls after heavy rain and in strong winds because the island is only about 4 km from the mainland coast. Box jellyfish are rare this far offshore but have been recorded, and Irukandji are possible: wear a stinger suit from November to May.

Cyclone season runs November-April. Enter at mid to high tide, as the reef flat is shallow at low water. Snorkel guides note visibility improves as the tide drops here; north-easterly winds and swell make the rock and north coast rough.

Enter near White Rock, descend on the reef edge and follow it around the rock and along the north coast at 5-12 m, using the marker buoys as turning points. Turn at half gas and return the same way, exiting on the beach at the north end of Welcome Bay.

Cairns Dive Centre (Fitzroy Island dive shop beside the resort pool) – guided beach dives, introductory dives and PADI courses; Fitzroy Island Sports Hub – snorkel and stinger-suit hire; Sunlover and Fitzroy Island Ferry – daily ferries; Snorkel Safari boat tour (twice daily) visits the northern reefs