Most of the world's best snorkelling spots reward you with quantity — a thousand small reef fish, a few corals, maybe a turtle if the day's going well. Cabbage Tree Bay does something rarer. It gives you a single fish that's almost certainly going to come and find you, look you in the eye, and follow you around the bay like a curious dog.
That fish is the Eastern Blue Groper (*Achoerodus viridis*), the state fish of New South Wales, and the protected centrepiece of one of the best urban snorkels on the planet. You can be in the water with one inside ten minutes of stepping off a Manly Ferry.
The fish
The blue groper is a giant wrasse — the largest in Australian waters. Adult males grow to about a metre and 20 kilograms, with a vivid cobalt-to-electric-blue body and a slightly humped forehead. Females and juveniles are russet brown-green, which throws first-time snorkellers — the "boring brown fish" hanging around the rocks is usually a groper too.
They are fearless, social, and openly curious about humans. A male will often track a snorkeller for an entire lap of the bay, stopping when you stop, hovering a metre from your mask. They've been fully protected from spearfishing in NSW since 1969 and from all fishing in this bay since 2002, which has produced generations that have never learned to fear people.
The spot
Cabbage Tree Bay is the 20-hectare aquatic reserve between Shelly Beach and Manly Beach — no fishing, no collecting, no anchoring. In two decades it has rebuilt a small, dense, almost-pristine temperate reef inside a city of five million people.
Beyond the gropers you will see crimson-banded wrasse, old wives, eastern blue devils, Port Jackson sharks, weedy sea dragons, green sea turtles, octopus, cuttlefish and rays.
The best entry is off Shelly Beach itself. Walk in from the sand, swim along the southern rocks, and the first big reef ledge about 50 metres out is where the resident male gropers patrol.
When to go
- January to April — water 21–23°C, warmest and busiest. A summer rashie is enough.
- May to August — water 17–19°C, often the clearest visibility and the quietest beach. You'll want a 3mm wetsuit.
- September to December — water 18–21°C, whales offshore, turtles increasing.
Early morning before the wind picks up is consistently best — flatter water, better light, fewer fins kicking up sand.
How to behave
- Don't touch them. They will come within arm's reach. Keep your hands at your sides.
- Don't feed them. It changes their behaviour and is illegal inside the reserve.
- Don't chase. They'll come to you if you stay still.
- Stay off the reef. Kicking the kelp damages the habitat you came to see.
- Watch the swell. Don't swim past the outside rocks if waves are breaking there.
Where to hire gear
### Snorkel and dive shops
- Dive Centre Manly — the largest and oldest dive shop on the peninsula. Full snorkel sets from around $35/day, wetsuits from $25. Also runs guided "Shelly snorkel" tours. 10 Belgrave St, two minutes from the Wharf.
- Pro Dive Manly — half-day snorkel sets around $30. Pittwater Rd.
- EcoTreasures Snorkel Tours — small-group guided snorkel tours of Cabbage Tree Bay (2 hours, includes all gear and a marine biologist guide). Best for first-timers.
- Manly Surf School — rents masks, fins and wetsuits from the North Steyne kiosk.
- Aloha Manly Surf — board and wetsuit hire on the South Steyne end of the Corso.
### Kayak, SUP and self-drive boat hire
- Manly Kayak Centre — "The Boatshed" — the most established water-toy hire in Manly. See the deep dive below.
- Sydney Harbour Kayaks — based at the Spit Bridge, offers guided trips into Manly Cove.
- Manly Surf 'n Slide — SUPs and bodyboards on weekends through summer; pop-up on Manly Beach.
A long look at The Boatshed (Manly Kayak Centre)
If you've stood on the East Esplanade side of Manly Cove and noticed the long, low, dark-timber shed with a green roof sitting right on the sand — that's it. The Boatshed, trading as Manly Kayak Centre, has been on this spot since 1990. Three generations of locals have learned to paddle here.
### What they do
- Kayak hire — single and double sit-on-tops from A$30/hour, half-day and full-day rates. Stable plastic boats designed for beginners who want to paddle out to Store Beach or around to Collins Flat.
- Stand-up paddleboard hire — from A$30/hour. Wide, stable boards ideal for first-timers on flat Manly Cove water.
- Self-drive leisure boat hire — from A$140 for the first hour, dropping to about A$80/hour after that. 12-foot aluminium centre-console runabouts with a small outboard. No boat licence required. Up to four adults, 9am to 5pm.
- Mini kayak tours — a 90-minute guided paddle around North Harbour, usually departing at 10:30am, currently discounted to A$50.
- Group bookings, picnics, gift vouchers, and Sydney's only "SUPball" league.
### Where to find them
On the western end of the Manly Cove beach, between the wharf and the ferry pontoons. Walk down off the ferry, turn left along the East Esplanade, and you'll see the green roof in about three minutes. They don't hire out in heavy weather — phone ahead if the forecast is windy.
### Why people come back
The reviews are unusually consistent: friendly owner, cheap gear by Sydney standards, and a genuinely beautiful location. You push off into a calm, sheltered cove with the city skyline in the background. The most common pairings:
1. Paddle to Store Beach — 25 minutes each way, lands on a sand-only beach you can't reach by foot. 2. Paddle around to Manly Wharf for fish and chips — 10 minutes, tie up at the small beach beside Hugo's. 3. Self-drive boat to Quarantine Beach — 15 minutes, beach yourself on Spring Cove, swim, drive back. 4. SUP yoga in flat morning water — popular before 8am when the cove is glass. 5. Group hen's/bucks/birthday flotilla — the operator handles parties of 20+ regularly.
### What The Boatshed is not
The Boatshed does not hire snorkel gear, masks or fins. If you want to combine kayaking and snorkelling, hire your mask and fins from Dive Centre Manly first, then walk to the Boatshed, then paddle around to Shelly Beach with the gear in a dry bag. It's a 15-minute paddle, the water inside the bay is flat, and you can land directly on the sand at Shelly.
The Boatshed also doesn't run motorised tours, dive trips, or whale-watching — they stick to what they do well: small-craft hire for people who want to mess about on the harbour.
Quick FAQ
Will I actually see a blue groper? On a calm-water day in summer, the resident male is sighted by more than 90% of snorkellers along the Shelly headland.
Is it safe for kids? Yes — Shelly Beach is one of Sydney's safest swimming beaches.
Are there sharks? Wobbegongs and Port Jackson sharks, both harmless and resident. No dangerous shark incidents in the reserve's modern history.
Do I need a guide? No — entry, exit and navigation are obvious. EcoTreasures is worth it if you want the marine biology.
Where can I shower and change? Showers and toilets at the Shelly Beach kiosk and at the Manly Surf Club end.
The honest summary
If you've got one morning in Manly and the wind is below 15 knots, walk past the Corso, past Fairy Bower pool, past the kiosk, drop into Shelly Beach, and put your face in the water. Within ten minutes, a metre-long electric-blue fish is going to come and check you out. There aren't many cities where that's a free, twenty-minute experience — and there isn't anywhere else in Sydney where it's so close to the wharf.
Hire your kit at Dive Centre Manly on the way in. Hire a kayak from The Boatshed on the way out. Eat fish and chips on the wharf before you catch the ferry home.
Plan your day
Pick the parts you like best and we'll stitch them into a sensible day, ferry times included. Build my itinerary →
