Marine life

Eastern Blue Groper

Achoerodus viridis

New South Wales' state fish — large, inquisitive and often the first thing to greet a Sydney shore diver.

Blue gropers are large, slow-moving wrasse that have become the unofficial mascot of Sydney shore diving. The big males are a startling electric blue; females and juveniles are brown to reddish.

They are notably inquisitive and frequently follow divers around a site, partly from curiosity and partly from decades of being hand-fed sea urchins — a practice now discouraged, since it changes behaviour and makes the fish trusting of anyone in the water, including spearfishers.

All blue gropers start life as females and the largest individuals change sex to male, which is why the big blue ones are always the biggest fish on the reef.

New South Wales diving, represented by an AI-generated editorial image.

Scientific name	Achoerodus viridis
Typical size	Commonly 50–90 cm
Peak months	Year-round
Documented sites	8
States	New South Wales

When to see them

possible good peak

Resident year-round on NSW rocky reefs.

Where they are

Documented sites for Eastern Blue Groper. Hover a marker for the site name.

Identification

large males vivid cobalt blue; females and juveniles brown to reddish-brown
heavy body with thick lips and prominent scales
powerful pectoral fins used for rowing-style swimming
often follows divers at close range

Behaviour

Feeds on urchins, molluscs and crustaceans, crushing them with strong teeth.
Changes sex from female to male with size and age.
Highly site-faithful — the same individual often occupies the same stretch of reef for years.

In-water etiquette

How divers behave around this species affects both the animal and everyone else's encounter.

Do not feed. Hand-feeding changes behaviour and makes fish vulnerable to spearfishing.
Do not touch, despite how close they come.

Where to see them

Sites where this species is documented as a reliable encounter.

Shelly Beach (Cabbage Tree Bay)Sydney's most forgiving shore entry, inside a protected aquatic reserve at Manly.Gordons BayAn Eastern Suburbs shore dive with a long-established underwater nature trail.ClovellyA sheltered concrete-lined channel giving Sydney's easiest entry into open water.Bare IslandSydney's most-dived shore site — weedy seadragons, extraordinary macro life and multiple routes.KurnellA cluster of Botany Bay shore dives including The Steps and The Leap, with wall terrain.Bass PointA rocky headland south of Wollongong with several entries and a protected reserve area.Jervis Bay WallsTemperate sponge-covered walls and drop-offs in some of the clearest water in NSW.Terrigal HavenA sheltered Central Coast shore entry used heavily for training and night diving.

Operators servicing those sites

Businesses documented as diving the sites above. Confirm seasonality and requirements directly.

Dive Centre ManlyA Northern Beaches operation with a long-standing presence at Shelly Beach, offering recreational training, boat diving and technical pathways.Dive Centre BondiAn Eastern Suburbs operation providing recreational training, local diving and technical pathways.Abyss Scuba DivingA Sydney operation associated with training across recreational and technical levels, boat diving and equipment services.Shellharbour ScubaA Shellharbour operation serving the Illawarra diving community, with access to Bass Point and local reef diving.Central Coast DiversA Central Coast operation serving the local diving community with training and equipment support.Terrigal Dive CentreA Terrigal business combining training, equipment support and access to local reef and wreck diving.

Often seen on the same dives

Australian & New Zealand Fur SealsFast, acrobatic and endlessly curious — the highlight of Montague Island, Jervis Bay and Port Phillip.Giant Australian CuttlefishThe world's largest cuttlefish, gathering in tens of thousands at Whyalla each winter.NudibranchsSea slugs of absurd colour and variety — the reason temperate Australian macro diving has a global reputation.Port Jackson SharkA small, harmless, harness-marked shark that gathers in southern NSW winters to breed.Weedy SeadragonThe leafy's more widespread cousin — the signature animal of Sydney and Victorian shore diving.WobbegongCarpet sharks so well camouflaged that most divers swim straight past them — and occasionally put a hand on one.

Frequently asked questions

Why are blue gropers so friendly?

They are naturally inquisitive, and decades of hand-feeding at popular Sydney sites reinforced it. Feeding is now discouraged because it makes the fish trusting of everyone in the water.

Are blue gropers protected?

They are protected from spearfishing in New South Wales, and the species is the NSW state fish.

Last researched: September 2026. Dive businesses change frequently — confirm current services, prices and requirements directly with the operator before booking.