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Norfolk Island's Reef

Discover a fragile paradise – Norfolk Island's beaches, lagoons and coral reef
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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.

Snubnose dart

Winter snorkelling on our reef

August 17, 2021

This week there has been some amazing, settled winter weather, the kind that makes Norfolk Island just sparkle and sing. And underwater was no different. Low, low tides associated with a new moon and quite good visibility have meant that my swims have been a delight.

This week, I was fortunate enough to see the male snubnose dart, Trachinotus blochii, cruising with his two female companions off the Salt House with a school of mullet. I am hoping this bodes well for some bubba darts in the coming summer season!

View fullsize Snubnose dart - Trachinotus blochii
Snubnose dart - Trachinotus blochii
View fullsize Snubnose dart - Trachinotus blochii
Snubnose dart - Trachinotus blochii
View fullsize Snubnose dart - Trachinotus blochii
Snubnose dart - Trachinotus blochii

Bluespine unicornfish - Naso unicornis

Other highlights included the bluespine unicornfish, Naso unicornis, posing for me in the early morning light, as only these fish can, before charging at me in a game of ‘call my bluff’. These guys are such show ponies! You can read about how unicornfish are so important to the health of a reef in an earlier blog post.

I also came nose to nose with our old resident female southern eagle ray, Myliobatis tenuicaudatus, with her distinctive stumpy tail, along with a brand new juvenile that I haven’t seen before in the shallows of Emily Bay. I photographed a pair courting inside Emily Bay back in December 2020. I wonder if this juvenile is the result (photos below).

But the one sighting that excited me beyond anything else was a teeny tiny juvenile blacktip morwong, Cheilodactylus francisi, on the Lone Pine side of the bay. This little fish, barely 1.5 to 2 cm in length, seemed unconcerned as I hovered over it trying to get a decent photo. I have only seen one of this species of fish in the bay, an adult, that lives in a very defined area, so it was a real treat to see what I have to assume is one of its progeny.

View fullsize Southern eagle ray - Myliobatis tenuicaudatus
Southern eagle ray - Myliobatis tenuicaudatus
View fullsize The new juvenile southern eagle ray
The new juvenile southern eagle ray
View fullsize This was taken in December 2020
This was taken in December 2020
View fullsize Blacktip morwong - Cheilodactylus francisi
Blacktip morwong - Cheilodactylus francisi
View fullsize Atagema spongiosa
Atagema spongiosa

I found a new species (to me) of sea slug in the bay as well, which is always exciting (photo above right), Atagema spongiosa.

And each time I was out I saw both resident green sea turtles snoozing in the channel, a couple of times within just a few metres of each other. They seem happy to take life in the slow lane for the time being and don’t swim off when I pause to observe them.

Today the weather has turned, with plenty of rain and blustery winds – more like the weather you would normally associate with winter.

That’s a wrap.

Tags snubnosed dart, Bluespine unicornfish, blacktip morwong, Atagema spongiosa, Green sea turtle, Southern Eagle Ray
← When corals go blue!The importance of sea urchins →
Featured
Signs of bleaching – 8 December 2025
Dec 8, 2025
Signs of bleaching – 8 December 2025
Dec 8, 2025

I took these photographs this morning, Monday, 8 December 2025. A few warm days of settled weather, little cloud cover and low tides in the hottest part of the day have led to some early bleaching on our reef. Bleaching doesn’t always mean death for our corals, but it is concerning to have this so early in the summer season. Fingers crossed the conditions don’t last and the reef can recover.

Dec 8, 2025
Nature is my teacher
Dec 3, 2025
Nature is my teacher
Dec 3, 2025

This is a thank-you note. Five years after my first Out on a swim post – written with zero marine science quals and a head full of questions – I’m still in the water, now as a PhD candidate, because an extraordinary mix of locals, volunteers, researchers and public servants decided to share what they knew. This is the story of how nature – and a very patient community – became my teachers.

Dec 3, 2025
Reef grief: what dredging has done to other reefs
Nov 30, 2025
Reef grief: what dredging has done to other reefs
Nov 30, 2025

From Miami to Fiji, from Dubai to tiny village harbours on atolls, dredging near coral reefs has left a long trail of scars – even on ‘small’ projects. This follow-up to last week’s Kingston post walks through real examples of what happened elsewhere, and what that should make us think about before we dig up our own reef.

Nov 30, 2025
To dredge or not to dredge? The Kingston Pier channel project
Nov 20, 2025
To dredge or not to dredge? The Kingston Pier channel project
Nov 20, 2025

How much risk are we really taking with the planned dredging at Kingston Pier – and how much protection do our corals actually have on paper? This piece walks through what the federal approval does and doesn’t guarantee, explains why sediment and light matter so much to the reef, and asks the hard questions we need answered before we trade a deeper channel for a shallower future.

Nov 20, 2025
A coral reef out of balance
Nov 8, 2025
A coral reef out of balance
Nov 8, 2025

After the long dry spell, the lagoon was crystal clear and full of life. But with the return of the rains, something else has returned too – the brown, filamentous mats of Lyngbya. It’s not seaweed, it’s a cyanobacterium, and when it takes hold it smothers coral and rubble alike. The reef’s way of showing us that every drop of water, from tank to tide, is connected.

Nov 8, 2025
Aglow among the spines
Oct 25, 2025
Aglow among the spines
Oct 25, 2025

Ever seen a sea urchin that seems to glow blue from the shadows? That’s Diadema savignyi showing off its reef shimmer. Beautiful, a little spiky, and definitely not to be messed with.

Oct 25, 2025
The funky seventies sea slug – Halgerda willeyi
Oct 15, 2025
The funky seventies sea slug – Halgerda willeyi
Oct 15, 2025

If ever a sea slug was channeling the 1970s, it’s Halgerda willeyi. With its groovy orange lines and chocolate-brown bumps, it looks straight out of a vintage lounge suite – the kind with shag pile carpet and bold floral cushions. Proof that nature was nailing retro design long before humans caught on.

Oct 15, 2025
Haddon's barometer
Oct 5, 2025
Haddon's barometer
Oct 5, 2025

This Haddon’s anemone has been quietly living in the middle of Norfolk Island’s Emily Bay for years, bleaching and recovering with the seasons. Like corals, sea anemones host microscopic algae that provide most of their food. When stressed by heat or rainfall changes, they lose colour – and tell a story about seasonal changes to the weather.

Oct 5, 2025
Honoured to be featured
Sep 30, 2025
Honoured to be featured
Sep 30, 2025

I left school in the UK nearly 50 years ago, so it was a pleasant surprise to be invited to share some images and take part in an interview for an article about my work, to be published in the annual glossy magazine the school now produces. Here is the end product.

Sep 30, 2025
Celebrating Biodiversity Month on Norfolk Island
Sep 7, 2025
Celebrating Biodiversity Month on Norfolk Island
Sep 7, 2025

September is Biodiversity Month – the perfect time to celebrate the astonishing variety of life on Norfolk Island’s reef. From new fish sightings to coral mosaics, every observation is a reminder of how much there is still to learn and protect.

Read more about why biodiversity matters, globally and right here in our lagoon.

Sep 7, 2025

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