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.

The sea-wolves of Emily Bay

January 21, 2021

Attracted by the easy pickings, I then watched as the silver trevally – Pseudocaranx sp 'dentex' – arrived. Like a sleek pack of wolves they swept around, in and out of the drum scooping up whatever they could. The fry shrank back, huddling together, trying to stay out of the maelstrom and away from so many hungry mouths.

Underwater wars! Aatuti versus the elegant wrasse

January 20, 2021

The banded scalyfin damselfish are keen underwater gardeners who don't take kindly to their carefully tended and guarded patches being raided by schools of elegant wrasse.

Goniopora norfolkensis – an uncommon coral

December 30, 2020

A reasonably common coral here is this beautiful brown, but sometimes creamy or caramel coloured fronded species called Goniopora norfolkensis..

Halfmoon grouper - Epinephelus rivulatus

Close encounter with a halfmoon grouper

December 18, 2020

A close encounter with a halfmoon grouper causes an amazing transformation from mottled red to mustard yellow.

Norfolk Island blenny, Parablennius serratolineatus

Cute as a button, the Norfolk Island blenny

December 13, 2020

The Norfolk Island blenny is a teeny little shy guy, who hangs out quite a bit at one end of Slaughter Bay and also in Cemetery. Extremely localised, they are endemic to Norfolk Island.

Juvenile Norfolk cardinalfish, Ostorhinchus norfolcensis, under the raft, Emily Bay

Mouth-brooding Norfolk cardinalfish

December 4, 2020

Norfolk cardinalfish are called big eyes on Norfolk Island, and it is easy to see why! These guys are mouth brooders, as in the male nurtures the eggs in his mouth.

The elite fleet

December 3, 2020

Like fragile jewels floating on the ocean currents, the common violet snail feeds on a fellow compatriots in the pleustal zone just beneath the ocean’s surface, the bluebottle. We should be grateful, because they are doing us a service by chomping on those stingers!

Oct 25, 2025

Aglow among the spines

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 15, 2025

The funky seventies sea slug – Halgerda willeyi

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 5, 2025

Haddon's barometer

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.

Sep 30, 2025

Honoured to be featured

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 7, 2025

Celebrating Biodiversity Month on Norfolk Island

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.

Aug 24, 2025

The fate of a coral colony when it succumbs to white syndrome – four years on

I’ve tracked one plating Acropora coral from 2021 to 2025. In just a few weeks, white syndrome wiped it out. Nearly four years years on, it’s still smothered in algae and sea squirts, with only the tiniest hint of new growth. It’s a stark reminder: without tackling the root cause, we’re just watching the same sad story repeat itself.

Aug 17, 2025

The Candy-Striped Cleaner Keeping the Reef Healthy

Candy-cane stripes, long white feelers, and a reef spa on offer – the banded coral shrimp waves its antennae to advertise cleaning services to passing fish.

Aug 10, 2025

Biomimicry: How a Boxfish Caught Mercedes Benz’s Eye

Meet Mr Lemonhead – our lagoon’s teeny yellow boxfish with a big design legacy. He inspired a Mercedes Benz concept car, proving how nature is full of surprises. And he shares the lagoon with other critters whose tricks have also shaped real-world inventions.

Aug 3, 2025

Patchwork Corals: How Colonies Fuse to Form Living Mosaics

Some corals wear more than one colour for a reason. When Paragoniastrea australensis colonies fuse early in life, they form living mosaics. A beautiful reminder of coral cooperation on Norfolk Island’s reef.

Jul 28, 2025

Reef relief

Today, 28 July, is World Nature Conservation Day. After the dry 2024, Norfolk Island’s reef is looking healthier – a brief reprieve as less water - laden with nutrients - flowed into the lagoon. These photos show what’s possible. It’s a reminder that recovery is within reach – though renewed runoff could quickly undo the gains.