Butterfly, flutterbyfish — 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.

DAY 17 – MARCH FOCUS ON NORFOLK ISLAND’S REEF

We shouldn’t have favourites, but if I am asked the raccoon butterflyfish would have to be mine

Butterflyfish are flighty, brightly coloured and beautifully conspicuous on our coral reef in their bright yellows and oranges, white and black livery. On Norfolk Island we regularly see fourteen species, just a small portion of the more than 100 species, globally.

They are generally quite territorial. Some species will often form a pair bond, which can last for life, and will lay claim to a patch of coral reef as their territory. Having said that, I have noticed others, such as the chevron, citron, and dot-and-dash butterflyfish, are often solitary.

At certain times of the year, usually when the corals are spawning, they will come together to form small schools. It was at coral spawning time that I took the photograph of the threadfin butterflyfish school, top.

Some species feed on corals and only corals, while others will consume plankton as well, but of all the fish that live on coral reefs, and there are thousands, only around 40 species like to crunch on hard coral and more than half of those are butterflyfish. Large numbers of butterflyfish are a good sign of a healthy reef.

The most common species on Norfolk Island’s reef is the threadfin butterflyfish and the least common are the dot-and-dash and the citron butterflyfishes.

Whatever the species, though, I get a real thrill when I get a nice clear photo of these delightful little fish.

Below are photos of our butterflyfish species found here on Norfolk Island. You can find many more images of butterflyfish at different stages of their lifecycle on the fishes page of this website. Scroll down to B for butterflyfish.

Black butterflyfish - Chaetodon flavirostris

Blackback butterflyfish - Chaetodon melannotus

Bluespot butterflyfish - Chaetodon plebeius

Chevron butterflyfish - Chaetodon trifascialis

Citron butterflyfish - Chaetodon citrinellus

Dot-and-dash Butterflyfish - Chaetodon pelewensis

Doublesaddle butterflyfish - Chaetodon ulietensis

Lined butterflyfish - Chaetodon lineolatus

Masked bannerfish - Heniochus monoceros

Oval-spot butterflyfish - Chaetodon speculum

Pinstriped butterflyfish - Chaetodon lunulatus

Raccoon butterflyfish - Chaetodon lunula

Threadfin butterflyfish - Chaetodon auriga

Three-striped butterflyfish - Chaetodon tricinctus

Vagabond butterflyfish - Chaetodon vagabundus

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?