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Norfolk Island's Reef

Discover a fragile paradise – Norfolk Island's beaches, lagoons and coral reef
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    • Kingston, Norfolk Island
    • Underwater
    • Reef Fish
    • Sharks
    • Eels
    • Corals
    • Sea Anemones
    • Nudibranchs, Sea Slugs and Flatworms
    • Octopuses
    • Sea Urchins and Sea Cucumbers
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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 blog is rated in the Top 20 Coral Reef Blogs in the world.

29 Mar 2021 (50).jpg

The sea-wolves of Emily Bay

January 21, 2021

Another underwater drama has been playing out in the shallows of Emily Bay over the last few weeks.

At the end of November, I photographed a mass of newly hatched fry gathered around what looks like an old oil drum. Over time they’ve grown bigger; In the following weeks I saw some of them in open water having left the safety of the drum's coral crevices, and other refuges, to head for the reef.

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View fullsize 23.11 (143)_reduced.jpg
View fullsize 19.11 (1)_reduced.jpg

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.

The fry’s numbers have been depleted considerably by these regular visits made by the insatiable trevally, but still some survive and are growing bigger by the day. They are mainly juvenile big eyes – the Norfolk cardinalfish, or Ostorhinchus norfolcensis – but there are also some juvenile smoky pullers – Chromis fumea – in their number.

Last week another visitor arrived on the scene. This time a lone blue trevally – Carangoides ferdau. It's agonising to watch, but then you also have to admire these sleek streamlined hunters as they speed around the tight corners, swooping on anything in their path.

View fullsize Blue trevally - Carangoides ferdau
Blue trevally - Carangoides ferdau
View fullsize Silver trevally - Pseudocaranx sp 'dentex'
Silver trevally - Pseudocaranx sp 'dentex'
View fullsize Silver trevally - Pseudocaranx sp 'dentex'
Silver trevally - Pseudocaranx sp 'dentex'
View fullsize Silver trevally - Pseudocaranx sp 'dentex'
Silver trevally - Pseudocaranx sp 'dentex'

You probably don’t realise it, but this daily drama unfolds right by your feet as you wade into the peacock-blue shallows of Emily Bay for a swim.

As an aside, in previous years, much of this action happened beneath the raft, where there was a fantastic underwater 'cave' for the babies. The new raft has very little space beneath its rafters because of the way it has been constructed. And of course the weed hasn't yet had a chance to grow back as luxuriantly as it was before. So far this year, very few fish have decided to make it their nursery. It will be interesting to see if that changes as the weed grows. I'll be watching with interest.

View fullsize February 2020 - beneath the raft
February 2020 - beneath the raft
View fullsize January 2021 - beneath the raft
January 2021 - beneath the raft
← Once a boy, always a boy – the marbled parrotfishUnderwater wars! Aatuti versus the elegant wrasse →
Featured
Glimpses of recovery: what the reef could be if we let it
Jun 13, 2025
Glimpses of recovery: what the reef could be if we let it
Jun 13, 2025

Day 6 of this photo series from Norfolk Island coincides with the final day of the UN Ocean Conference in Nice. After a week of documenting decline, today’s post offers a different view – what reef recovery can look like when conditions improve. Drought in 2024 gave the reef a break, and the results were unmistakable: healthier corals, lower disease, and more fish. This is what’s possible if we act.

Jun 13, 2025
Warning signs: quiet and unnoticed collapse of two coral colonies
Jun 12, 2025
Warning signs: quiet and unnoticed collapse of two coral colonies
Jun 12, 2025

Day 5 of my blog series for the UN Ocean Conference: two long-lived coral colonies in Norfolk’s lagoon died quietly from disease. No drama – just slow collapse and overgrowth by algae. A reminder that not all reef losses are loud, but they are happening.

Jun 12, 2025
Warning signs:  what Norfolk Island’s reef is telling us
Jun 11, 2025
Warning signs: what Norfolk Island’s reef is telling us
Jun 11, 2025

Day 4 of a week-long photo series from Norfolk Island, shared during the UN Ocean Conference in Nice. Today’s post spotlights a Hydnophora pilosa colony where white syndrome appeared suddenly and spread quickly, taking out around a quarter of the coral. In the months that followed, algae quietly filled the gap – a subtle but telling shift from coral to algae that’s happening across the reef.

Jun 11, 2025
Warning signs: coral disease takes hold
Jun 10, 2025
Warning signs: coral disease takes hold
Jun 10, 2025

In Day 3 of this blog post series, published while leaders gather at the UN Ocean Conference in Nice, we see Norfolk Island’s coral reef lagoon quietly delivering a stark warning: recurrent land-based pollution, coral disease, and delayed decisions are dismantling this ecosystem in real time.

Jun 10, 2025
Warning signs: coral growth anomalies – the slow cancers of the reef
Jun 9, 2025
Warning signs: coral growth anomalies – the slow cancers of the reef
Jun 9, 2025

Day 2’s post coinciding with the UN Ocean Conference looks at coral growth anomalies – sometimes called coral ‘cancers’. These slow-moving diseases quietly weaken coral colonies, making them far more vulnerable to storm damage and algal takeover. On Norfolk Island’s reef, I’ve watched this exact process play out over several years. This is how chronic stress silently dismantles coral ecosystems.

Jun 9, 2025
Warning signs: shifting baselines on Norfolk Island’s reef
Jun 8, 2025
Warning signs: shifting baselines on Norfolk Island’s reef
Jun 8, 2025

Today is World Ocean Day — a timely moment to launch my week-long blog series on Norfolk Island’s reef. Each day this week, I’ll be sharing photo essays that document the slow but steady pressures reshaping this fragile reef. Today: how shifting baselines make us blind to what we’ve already lost.

Jun 8, 2025
The Governance–Government Vacuum: Norfolk Island’s Forgotten Ecology
Apr 29, 2025
The Governance–Government Vacuum: Norfolk Island’s Forgotten Ecology
Apr 29, 2025

A personal reflection on Norfolk Island’s coral reef environment, political denial, and what John Wyndham’s The Kraken Wakes can still teach us about slow-moving disasters — and why this election matters more than ever.

Apr 29, 2025
Cute as buttons – Astrea curta
Feb 20, 2025
Cute as buttons – Astrea curta
Feb 20, 2025

Astrea curta corals are ‘small, moderately plocoid [flattened], distinct, and almost circular’ . Normally grey-green in colour, you can see from the images here, ours are often beautiful rich gold, although they do vary. They have a neat growth habit and button-like corallites, which can grow in columns, spherically or flattened. Large colonies of these can form gorgeous undulating bumps.

Feb 20, 2025
From 'Watch' to 'Warning'
Jan 26, 2025
From 'Watch' to 'Warning'
Jan 26, 2025

Last week, the chance of coral bleaching in Norfolk Island’s inshore lagoons was raised from ‘Watch’ to ‘Warning’ and will more than likely rise to Alert levels one and two in coming weeks. So why do I worry about water quality all the time when bleaching seems inevitable these days and so the reef is probably doomed anyway? Read on to find out.

Jan 26, 2025
From little things – watching them grow
Jan 4, 2025
From little things – watching them grow
Jan 4, 2025

Small numbers of different fish species is not an unusual phenomenon on Norfolk Island’s reef, but it does demonstrate what a tiny, precious, coral reef ecosystem we have, when we can count individuals on one hand and watch each of them grow, like these little blackeye thicklips, a member of the wrasse family.

Jan 4, 2025

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