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 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

Jun 13, 2025

Glimpses of recovery: what the reef could be if we let it

Day 6 of this photo series from Norfolk Island coincides with the final day of the UN Ocean Conference in Nice. After a week of documenting decline, today’s post offers a different view – what reef recovery can look like when conditions improve. Drought in 2024 gave the reef a break, and the results were unmistakable: healthier corals, lower disease, and more fish. This is what’s possible if we act.

Jun 12, 2025

Warning signs: quiet and unnoticed collapse of two coral colonies

Day 5 of my blog series for the UN Ocean Conference: two long-lived coral colonies in Norfolk’s lagoon died quietly from disease. No drama – just slow collapse and overgrowth by algae. A reminder that not all reef losses are loud, but they are happening.

Jun 11, 2025

Warning signs: what Norfolk Island’s reef is telling us

Day 4 of a week-long photo series from Norfolk Island, shared during the UN Ocean Conference in Nice. Today’s post spotlights a Hydnophora pilosa colony where white syndrome appeared suddenly and spread quickly, taking out around a quarter of the coral. In the months that followed, algae quietly filled the gap – a subtle but telling shift from coral to algae that’s happening across the reef.

Jun 10, 2025

Warning signs: coral disease takes hold

In Day 3 of this blog post series, published while leaders gather at the UN Ocean Conference in Nice, we see Norfolk Island’s coral reef lagoon quietly delivering a stark warning: recurrent land-based pollution, coral disease, and delayed decisions are dismantling this ecosystem in real time.

Jun 9, 2025

Warning signs: coral growth anomalies – the slow cancers of the reef

Day 2’s post coinciding with the UN Ocean Conference looks at coral growth anomalies – sometimes called coral ‘cancers’. These slow-moving diseases quietly weaken coral colonies, making them far more vulnerable to storm damage and algal takeover. On Norfolk Island’s reef, I’ve watched this exact process play out over several years. This is how chronic stress silently dismantles coral ecosystems.

Jun 8, 2025

Warning signs: shifting baselines on Norfolk Island’s reef

Today is World Ocean Day — a timely moment to launch my week-long blog series on Norfolk Island’s reef. Each day this week, I’ll be sharing photo essays that document the slow but steady pressures reshaping this fragile reef. Today: how shifting baselines make us blind to what we’ve already lost.

Apr 29, 2025

The Governance–Government Vacuum: Norfolk Island’s Forgotten Ecology

A personal reflection on Norfolk Island’s coral reef environment, political denial, and what John Wyndham’s The Kraken Wakes can still teach us about slow-moving disasters — and why this election matters more than ever.

Feb 20, 2025

Cute as buttons – Astrea curta

Astrea curta corals are ‘small, moderately plocoid [flattened], distinct, and almost circular’ . Normally grey-green in colour, you can see from the images here, ours are often beautiful rich gold, although they do vary. They have a neat growth habit and button-like corallites, which can grow in columns, spherically or flattened. Large colonies of these can form gorgeous undulating bumps.

Jan 26, 2025

From 'Watch' to 'Warning'

Last week, the chance of coral bleaching in Norfolk Island’s inshore lagoons was raised from ‘Watch’ to ‘Warning’ and will more than likely rise to Alert levels one and two in coming weeks. So why do I worry about water quality all the time when bleaching seems inevitable these days and so the reef is probably doomed anyway? Read on to find out.

Jan 4, 2025

From little things – watching them grow

Small numbers of different fish species is not an unusual phenomenon on Norfolk Island’s reef, but it does demonstrate what a tiny, precious, coral reef ecosystem we have, when we can count individuals on one hand and watch each of them grow, like these little blackeye thicklips, a member of the wrasse family.