Overview
Dyer Island sits a short distance off the southern shore of Rottnest Island, close to Porpoise Bay and Catherine Bay.
Although small and exposed, it’s a beautiful spot for a quick visit in calm weather. The island is surrounded by clear water, limestone ledges and scattered bommies that make it popular with divers and snorkellers.
This is not an overnight anchorage, and not suitable for deep-draft monohulls. Only shallow-draft multihulls or tenders should approach the area, and only in light conditions.
Anchorage & Conditions
- Best visited in light easterly winds or very calm weather.
- The surrounding seabed is a mix of sand, reef and shallow bommies, with depths changing rapidly.
- Suitable only for:
- Shallow-draft multihulls
- Tenders
- Careful day visits, not anchoring close in.
Anchoring close to the island is not recommended due to reef structures and surge.
A safer approach is to anchor further out in a known sandy patch and explore by tender.
Wave rebound from the island can be significant in any swell — avoid the area in strong southerlies or when the swell exceeds 1m.
Things to Do
- Snorkelling & diving: Clear water and excellent visibility around the limestone ledges.
- Swimming: Turquoise pockets on calm days.
- Exploring by tender: Great for cruising around the small caves, ledges and reef systems.
- Photography: Beautiful views across the south side of Rottnest.
Notes & Hazards
- Extensive shallow reefs and bommies surround the island — charts and a lookout are essential.
- Not suitable for keelboats or deep-draft monohulls.
- Swell can wrap around unexpectedly, even on calm days.
- The island is an important seabird site — keep clear and avoid landing.
Location
- Approx. position: 32°00.75'S, 115°29.22'E
- Just off the southern side of Rottnest Island, between Porpoise Bay and Parker Point.
Source: Local sailing knowledge & practical WA cruising experience.