A smooth and slippery echidna — 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.

If you are a trivia nut, you’ll like this one!

Here on Norfolk Island, I do a Reef Brief each Monday, where I talk about Norfolk Island’s reef, the connectedness of ecosystems and the critters that live there. And I often get asked some fascinating questions, some of which I have to take on notice. One such, which has been asked a couple of times now, is this:

How did the snowflake moray get its proper (scientific) name Echidna nebulosa, and what does it have to do with Australia’s famous and iconic marsupial, the echidna?

Excellent question. I had no idea. So I did a bit of research to find the answer.

In Greek mythology, Echidna was a half-woman, half-snake monster who lived along in a cave. In other words, a bit of this and a bit of that. You can read more about her on a comprehensive Wikipedia page on the topic.

Which is why, in 1797, Baron Georges Cuvier suggested this name for the echidna marsupial to reflect its combined mammalian and reptilian characteristics. However, predating Cuvier’s naming of the echidna, in 1789, the snowflake moray had already snagged the scientific name, Echidna (genus) nebulosa (species) had already snagged the scientific name of Echidna. Consequently, Cuvier’s name was relegated to being the marsupial echidna’s common, or generic, name. So, for example, the short-beaked echidna, which is found in Austalia, is known as the Tachyglossus aculeatus.

But returning to the snowflake moray: it is one of 11 species of moray in the Echidna family, presumably so named to reflect its snake-like qualities. It goes by several other common names, including Bosch’s reef-eel, clouded eel, clouded moray, clouded reef eel and starry eel.

To complicate matters further, there is the Atractus echidna (genus + species), a fairly recently recognised species of snake, where the species name of Echidna refers to its contrasting anterior/posterior colouration pattern, referencing Echidna of Greek mythology’s hybrid nature (which makes sense).

So there you go!

November 3, 2026

Familiar faces – getting to know the reef’s residents

Six years of swimming the same little reef have introduced me to some unforgettable characters that I’ve followed over time. From familiar fish and anemones to turtles and a snail’s eggs, this final article in my photographic series explores what I’ve learned about the lives of individual animals simply by returning, watching and taking photographs.

November 1, 2026

When algae move in – the changing reef neighbourhood

Algae are a natural part of Norfolk Island's reef, changing with the underwater seasons. But sometimes their beautiful green growth conceals a rather sad story. In the fifth article of my six-part photographic series, I revisit familiar places to see how algae have changed over the years – and what might be hiding underneath.

October 30, 2026

The slow disappearance – disease on the reef

What happens after coral disease has run its course? In the fourth article of my six-part photographic series, I revisit colonies I've watched lose living tissue, sometimes alarmingly quickly. From a potentially century-old brain coral that lost most of its living tissue in less than 100 days to the algae-covered skeletons left years later, these photographs reveal the longer-term consequences of coral disease on Norfolk Island's reef.

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?