No, it's not a parrotfish! — Norfolk Island's Reef

Out on A Swim

‘Out on a swim’ is a coral reef blog that tells the stories of the characters who live under the waves and what has caught my eye when ‘out on a swim’ in the lagoons of Norfolk Island. It is also a record of the difficulties Norfolk Island’s reef faces, like many others around the world, as a result of the poor water quality that has been allowed to flow onto it.

This page shows the most recent blog posts. For the complete catalogue, visit the ‘Out on a swim index’ page.

This blog is rated in the Top 20 Coral Reef Blogs in the world.

I often get people excitedly telling me how they have seen a parrotfish. And it is quite possible that they have. But to be honest, the few parrotfish that we do have are rather dull when compared with their more flamboyant wrasse cousins and there are very few of them, both in numbers of parrotfish species and in the numbers you will see of each one. If I see a parrotfish, any parrotfish at all, it is rare. And when I do see them it is often just an individual or possibly a small family group. So it is more likely that the large brightly coloured fish they are telling me about is either a surge wrasse – Thalassoma purpureum, or a green moon wrasse – Thalassoma lutescens, both of which are plentiful in the lagoons.

Green moon wrasse - *Thalassoma lutescens*

I have observed five species of parrotfish inside the reef. You can find them all under P for parrotfish if you scroll down on my fish page on this website. Keep scrolling down to W for wrasse to see the amazing variety of these.

Parrotfish are a subspecies of the wrasse family. Like wrasses, they swim using their pectoral (side) fins, which can look a little like mini wings as they move through the water.

One of the features that sets them apart from wrasses is their toothy grin and fused teeth – about 1000 of them lined up in 15 rows – in a beak-like form, hence their name. They eat ‘microscopic filamentous bacteria that live on, and just a few millimeters underneath, the calcareous surface of the reef’, and to get at these they chow down on the hard coral skeletons. More teeth in their throat (plates known as a pharyngeal mill) grind the coral into a paste so they can extract the nutritious coral polyps and algae. What comes out the other end is beautiful white sand.

Wrasse, on the other hand, like to consume invertebrates, such as shrimps, crabs, sea urchins and gastropods. They have soft protractile lips to help them nibble.

Parrotfish are vital to the health of coral reefs. In places where they have been overfished, the ecosystem is not as productive. So perhaps it’s best to leave them where they are.

More information about parrotfish can be found in this fascinating article from the Smithsonian here: ‘Tough Teeth and Parrotfish Poop’, Ocean.

Bluebarred parrotfish - Scarus ghobban

Marbled parrotfish - Leptoscarus vaigiensis

Pacific Bullethead Parrotfish - Chlorurus spilurus

Palenose parrotfish - Scarus psittacus

Surf parrotfish - Scarus rivulatus

Fused front teeth of the bluebarred parrotfish

October 28, 2026

When storms rearrange the reef

Sometimes the sea rearranges a reef in a matter of hours! In the third article of my six-part photographic series, I revisit corals broken, overturned or swept away by powerful swells and storm surges. Some disappeared altogether, while others found surprising ways to survive. Five photographic sequences reveal just how dramatically Norfolk Island's reef can change.

October 26, 2026

When the reef fights back – coral growth and recovery

Not every coral story ends badly! Among six years of underwater photographs are some wonderful examples of growth, survival and recovery. From corals that have grown spectacularly to others that have survived bleaching, breakage or even being turned upside down, this second article in my photographic series celebrates some of the reef's more encouraging stories.

October 24, 2026

The neighbours – six years of watching the same reef

When I began photographing Norfolk Island's reef in 2020, I simply recorded whatever caught my eye. Six years later, those photographs have become a record of individual corals and their changing fortunes – growth, competition, survival and loss. This is the first of six articles looking back at what I've seen, and sometimes what I wish I hadn't.

October 10, 2026

Pulling the rugosity from out of the reef

What do ‘rugosity’, structural complexity and channeling your inner fish have in common? Quite a lot, as it turns out. This week I’m looking at how all the lumps, bumps, branches, holes and ledges on a reef create habitat – with a brief detour into one of my long-standing tricks for navigating tertiary study: write down the jargon until it starts to make sense.

September 27, 2026

How does a sea slug smell?

It started with a close-up of a little Elysia and two rhinophores that looked like tiny rolled-up scrolls. Once I noticed them, I started going back through years of sea-slug photos and realised just how wildly different these sensory organs can be – ridged, rolled, curled, tubular and, in sea hares, distinctly rabbit-eared. So this week’s rabbit hole is all about how sea slugs ‘smell’ underwater, and why their noses come in so many different shapes.

September 19, 2026

The Elite Fleet sails in

Nearly six years ago, my very first blog post was about the strange blue and violet creatures that live at the ocean’s surface – a group I christened Norfolk Island’s ‘Elite Fleet’. Since then I’ve seen plenty of bluebottles and the occasional violet sea snail, but never a by-the-wind sailor. Until this morning. Velella velella is not a true jellyfish, but a colonial hydrozoan with a transparent sail that lets the wind help carry it across the ocean. So what exactly is this extraordinary little creature, how does it ‘sail’, and what connects it to the rest of the fleet?

September 18, 2026

In a nutshell – where I stand on the proposed Norfolk Island Marine Park

I support the proposed expansion of Norfolk Marine Park and its renaming as Norfolk Island Marine Park. There is much to welcome – strong offshore protection, no mining, and recognition of the importance of sustainable local fishing. But I also have some reservations. Why does Cascade need to be removed from the Marine Park at all? How will more than 430,000 km² actually be monitored and enforced? How do we make sure Norfolk people have a genuine role in management? And, above all, how do we ensure that the enormous new park does not draw attention away from the small, stressed reef immediately beside us?

September 13, 2026

No seagrass, but plenty of turtles

Norfolk Island does not have seagrass, although one of our most conspicuous green algae is often mistaken for it. Feather and grape Caulerpa can both form striking patches across the lagoon. I take a closer look at what Caulerpa actually is, why it is so easily confused with seagrass, and where our green turtles fit into the story.

September 6, 2026

Watching El Niño from Norfolk Island

El Niño is strengthening across the Pacific, but that does not tell us exactly what the coming months will bring to Norfolk Island. After a long wet spell, I am watching our rainfall and water supplies more closely again – and, underwater, keeping an eye on sea temperature, algae, coral recruits and the fish that turn up on the reef.

September 2, 2026

What the world’s reefs are telling Norfolk Island

Two major new coral reef reports carry a clear message for Norfolk Island: reefs can recover when pressures ease, but the time available for recovery is shrinking. Norfolk Islanders were raising concerns about water quality, runoff and the health of Emily and Slaughter Bays nearly forty years ago. Today we have much better science, a changing climate and a far clearer understanding of how closely the catchment and reef are connected. This article looks at what that means for water quality, long-term monitoring, dredging and how we manage Kingston from land to sea.