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.

Charisma plus! The bluespine unicornfish

April 6, 2021

One of the many characterful fish in the Emily and Slaughter Bay environs on Norfolk Island are the bluespine unicornfish, more properly known as Naso unicornis. These guys love to pose for the camera, showing off their best side, and then shifting so you can get a shot of the other.

The doubleheader's double life!

February 28, 2021

Love these doubleheader wrasse, Coris bulbifrons. Beautiful deep smoky blue with a big bulge on their forehead, they will quite often just casually cruise on past. Like many wrasse, they change sex, colour and appearance quite radically as they age and grow.

When the yelloweye leatherjackets go courting

February 10, 2021

How special to see this. Normally shy and a little timid, these little leatherjackets were quite happy concentrating on each other as I watched them courting.

A little mado with attitude!

February 10, 2021

This little eastern footballer or mado has suddenly started hanging with a family of stripeys that I've been watching. But it always keeps slightly apart, aloof, even. In fact, sometimes it almost seems like it is herding them - and giving lectures! This guy definitely has attitude!

Marbled parrotfish - Leptoscarus vaigiensis — Marbled parrotfish - *Leptoscarus vaigiensis*

Once a boy, always a boy – the marbled parrotfish

February 4, 2021

The marbled parrotfish (Leptoscarus vaigiensis) likes to camouflage itself, disappearing into the seagrass and algae on which it feeds.

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!

Dec 15, 2025

Herbicides, heritage, and an inshore reef: what happens when land management meets lagoon health

Herbicide use near Emily, Slaughter and Cemetery Bays raises questions about inshore reef health, heritage land management, and environmental protection on Norfolk Island.

Dec 8, 2025

Signs of bleaching – 8 December 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 3, 2025

Nature is my teacher

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.

Nov 30, 2025

Reef grief: what dredging has done to other reefs

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 20, 2025

To dredge or not to dredge? The Kingston Pier channel project

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 8, 2025

A coral reef out of balance

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.

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.