Guide to Marine Life at Rottnest Island: What You Can See

Imagine a place where you can see the ocean's vibrant marine life on full display right before your eyes.

5 minutes

Long-nosed fur seals at Cathedral Rocks

Exploring the marine world of Wadjemup / Rottnest Island is an unforgettable experience. With 63 pristine beaches and 20 stunning bays, the island is teeming with vibrant sea life both above and below the surface.

From drifting over thriving coral reefs and seagrass meadows to exploring historic shipwrecks and spotting migrating whales or playful seals, Wadjemup offers marine encounters to suit every kind of ocean lover.

Why Rottnest Island's Marine Life Stands Out

The crystal-clear waters surrounding Rottnest Island are incredibly biodiverse and bountiful in colour. Thanks to the warm Leeuwin Current, which flows south from Indonesia, the island enjoys a unique mix of tropical and temperate conditions. This creates an ideal environment for coral to flourish across the island's five marine sanctuary zones.

But it’s not just the water temperatures and coral gardens that make snorkelling here so special. Once connected to the mainland, the island’s underwater limestone formations now offer an intricate network of ridges, swim-throughs, caverns, and sheltered nooks. These natural structures create thriving habitats for more than 400 fish species.

Before You Dive In

It’s important to respect the marine environment when exploring the colourful underwater world. Avoid touching or taking anything from the reef to help preserve its delicate ecosystem for future generations.

Encounter Iconic Marine Species

From the Ocean

There’s no better way to truly experience the wonder of the island’s marine world than being fully immersed in it. Whether you snorkel, swim, or dive, you’ll find yourself surrounded by some of the island’s most fascinating residents.

Djildjit / Tropical Fish

With warm, inviting waters and lush coral landscapes, Wadjemup is a paradise for snorkellers and divers. Hundreds of tropical fish species call these reefs home, weaving through colourful formations and underwater foliage.

Here are just some of the species you may encounter:

King Wrasse: One of the most commonly sighted fish around the island, you'll often find them swimming along the edges of reefs or hiding between seagrass and rocks. They’re especially memorable because they change colour as they grow. You'll see the black and white of small juveniles, the pinkish-white larger juveniles and females with a dark red stripe, and the striking pink of large males with blue and yellow lines.

Western Blue Devilfish: Hard to miss in colour but often hard to spot, this species offers a deep blue display with scattered blue spots and long, trailing fins. They prefer the shadows of rocky reefs, caves and crevices, rarely straying far from their chosen hideaways.

Nudibranchs: A favourite find for snorkellers, nudibranchs are a type of sea slug with vivid colours, intricate patterns and feathery gills. The WA nudibranch is particularly eye-catching, featuring pale blue patches on its back, orange gills and tentacles, and orange and black stripes along its body, topped off with clusters of feathery-like structures.

Nudibranchs

Close-up underwater photo of a rock lobster among green seaweed, with its detailed exoskeleton and long antennae visible.

Maran (Western Rock Lobster)

King Wrasse

Booyi (Turtle)

A man in a white shirt snorkeling near coral

Snorkelling in Wadjemup’s crystal blue waters

Bamba / Stingrays: Stingrays, particularly the graceful eagle ray, are commonly seen gliding over sandy seafloors or resting beneath a thin layer of sand. You may encounter them while swimming, but you can often spot them from the shore as well. Calm bays such as Geordie Bay, Longreach Bay, Parakeet Bay, and Thomson Bay are great places to watch these gentle creatures cruise by.

Maran / Western Rock Lobster: The western rock lobster is one of around eight rock lobster species found along Western Australia’s coastline. These short-bodied, ten-legged crustaceans are easily recognised by their reddish-brown shells and are commonly seen in the waters around Rottnest Island. They typically gather in groups, sheltering in caves and beneath reef ledges.

Prefer to meet a lobster above water? Join Rottnest Cruises Luxe Island Seafood Cruise, where you can help pull in cray pots, learn about sustainable fishing, and enjoy a seven-course lunch all cooked by a private onboard chef. Tours are seasonal and typically operate from November to April.

Booyi / Turtles: Although sightings are rare, green turtles do occasionally appear around Wadjemup. Those that venture to the island can be identified by their beautiful shells which are a blend of brown, olive green, reddish hues and black on top, with a pale underside.

From Land

You don’t need to get wet to experience some of the island’s most impressive marine life. From coastal lookouts to boat tours, there are plenty of ways to admire some of the island’s ocean inhabitants from dry land.

Manyil / Long-nosed fur seals: Head to Cathedral Rocks at the island’s West End to see a thriving colony of long-nosed fur seals. This raised viewing platform gives you the perfect vantage point to watch these brown-furred locals lounging, playing, and warming themselves just below the platform or on the larger rocks further out. For an even closer look, make use of the binoculars available at the lookout.

Kwilena / Dolphins: Wadjemup’s surrounding waters are home to a population of bottlenose dolphins, which can be spotted year-round as they glide, surf, and play along the coastline. These curious mammals surface frequently to breathe, making them relatively easy to spot from the beaches. If you’re lucky, you may even witness them riding waves or leaping out of the water.

Maamoong / Whales: Between August and December, but sometimes as early as June, humpback whales and southern right whales can often be seen as they migrate along the coast. Watch for tell-tale blowhole sprays, tail slaps, and the occasional breach as these gentle giants pass by Wadjemup.

You can catch a spectacular view of their journey from land at West End and other lookout points. For a guided experience, join an Eco Express Boat Tour or scenic flight with Rottnest Air Taxi for a chance to spot them from a different perspective.

A whale breaching backwards with Rottnest Island in the background

Spot migrating whales

Binoculars are available at West End

Manyil (Long-Nosed Fur Seals)

Cathedral Rocks Viewing Platform

Explore With a Guide or Go Your Own Way

Enhance your marine adventure with a guided experience. Join Rottnest Snorkel to discover the island's best underwater locations with knowledgeable guides. Or, set out on a snorkel and sail tour on board Charter 1's iconic catamaran. If you're after a full day of adventure both on land and in the water, join Laura the Explorer on a cycling tour, complete with snorkelling stops throughout the day. If you prefer to stay dry, cruise along the coastline on an Eco Express Boat Tour in search of wildlife.

Rather explore at your own pace? You can easily hire snorkelling gear from Pedal & Flipper Hire or Rottnest Rentals before setting off on your self-guided adventure.