Turtles and snake eels — 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.

We’ve had yet another week of south easterlies stirring up the bays making visibility poor for taking photographs. That doesn’t mean I haven’t enjoyed my swims, though. Emily Bay never fails to lift my spirits.

A really exciting observation for me this week was the spotfin squirrelfish, Neoniphon samara. I can count on one hand the number of times I’ve seen this guy (and I am pretty sure it is the same one) in the last couple of years. That is because they are nocturnal (a clue to this is their huge eyes). This fish is very shy and ducks under an Acropora coral shelf very fast when it sees me, so you have to point and shoot really quickly – with varying results! It lives under these coral shelves during the day and then emerges out to the seagrass beds and hard-bottomed habitats at night, when it feeds on shrimps, small crabs and fish. (Reference Fishbase and Bray, D.J. 2020, Neoniphon sammara in Fishes of Australia, both accessed 28 Sep 2021.)

I also observed several snake eels out and about this week: two convict eels, Leiuranus versicolor, and one banded snake eel, Leiuranus semicinctus. I have put three up here for you to see (two top images and bottom left). The markings, even in the same species, are quite different and change as they age. You can see more of these snake eels, as well as the varieties of moray eels, over on the eels page of this website. They are quite docile and are usually found in the sandy reaches of the bay – they can bury themselves in the sand as quick as a flash. We also find a spotted snake eel, called the ocellate snake eel, Myrichthys maculosus, in our bays from time to time. So you can see the difference, I’ve included an image of this one taken a few months ago (bottom right)..

Here’s some quick snake eel facts for you:

They are a fish, and not a snake (an eel is a type of fish).
They breathe underwater using gills (snakes have lungs).
They can live up to 20 years.
They are nocturnal animals, which is why it is always exciting to see one during the daytime.
They bury themselves in the sand to hide from predators.

Banded snake eel - Leiuranus semicinctus

Convict snake eel - Leiuranus versicolor

Ocellate snake eel - Myrichthys maculosus

We have two resident green sea turtles, Chelonia mydas, that seem to snooze quite a bit. When I see them both they are normally at least 5 m or 6 m apart, if not a lot further. Today, they were catnapping very close to each other.

Finally, tonight is my debut as an actor! I’ve been rehearsing really hard over some weeks for my 10-second cameo, playing myself as the person who photographed the mullet with a gold ring around its head! Hilarious! Paul Garnsey, an island resident, used the story as inspo for a short play called Goldfish. Wish me luck!

Until next week …

Green sea turtles - Chelonia mydas

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.