They look alike at first glance, but Alveopora and flowerpot corals are not the same. The easiest way to tell them apart is to count the tentacles.
Read MoreA juvenile flowerpot coral (Goniopora)
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.
Read MoreThe flowerpot coral, Genus Goniopora, Norfolk Island, which I thought was a sea anemone (below)!
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.
Read MoreThis patch of Acropora is close to the colony discussed in this blog post, and is similar to how it would have once looked before disease took hold in that area..
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.
Read MoreReef 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.
Read MoreGlimpses of recovery: what the reef could be if we let it
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.
Read MoreHynophora pilosa colony, Norfolk Island
Warning signs: what Norfolk Island’s reef is telling us
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.
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Lone Pine, Emily Bay, Norfolk Island
Warning signs: coral disease takes hold
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.
Read MoreAn Acropora coral colony, Emily Bay, Norfolk Island, showing early signs of growth anomalies
Warning signs: coral growth anomalies – the slow cancers of the reef
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.
Read MoreHealthy montipora coral, Norfolk Island
Warning signs: shifting baselines on Norfolk Island’s reef
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.
Read MoreFrom little things – watching them grow
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.
Read MoreEmily Bay at low tide, early morning, December 2024
A year in review – 2024 on Norfolk Island’s Reef
It is five years since I began wielding a camera underwater in Norfolk Island’s lagoons and my third ‘year in review’ for this ‘Out on a swim’ blog. And what a journey it has been. At least this year I have some great news to report, but – a bit like a curate’s egg (partly bad and partly good) – there are also some downers. Find out what 2024 has meant for Norfolk Island’s reef.
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Feisty zingers! Focus on the 'brain' coral, Paragoniastrea spp.
If corals had characters, then the Paragoniastrea spp. would be described as feisty, or even downright aggressive when it comes to asserting itself over its neighbours. They are also rather colourful.
Read MoreMontipora corals, Norfolk Island
Gorgeous, boring and brown!
Gorgeous, boring brown, Montipora corals! These beautiful coral colonies (and remember, these consist of loads of tiny little animals, which work together to create these amazing shapes) are one of our key reef-building corals. There are around 85 known species belonging to the Montipora genus.
Read MoreYou may call this beauty 'Lobophyllia recta sensu Veron'
One of the first corals to catch my eye when I set out with my new camera in January 2020 was this stunning boulder coral that sits off the Salt House in Emily Bay. Regular swimmers would all be aware of its presence, but not many would realise that it is quite possibly an as-yet undescribed species of coral, which for the moment is known as Lobophyllia recta sensu Veron.
Read MoreA juvenile Hawksbill sea turtle, Eretmochelys imbricata, inside Emily Bay lagoon, Norfolk Island, listed as critically endangered, according to the IUCN Red List, and vulnerable under the EPBC Act
'Barometers of life' – National Threatened Species Day
Today's National Threatened Species Day post discusses the conundrum of Australia's threatened species list and the IUCN Red List as they relate to vulnerable and threatened species here on Norfolk Island in the Marine Park. How, for example, do we offer protections to something that hasn't been formally identified yet, let alone listed as threatened?
Read MoreThe Emily Bay’s massive ‘brain’ coral, Paragoniastrea australensis, photographed on 6 July 2024
While you were sleeping ...
This massive and incredibly slow-growing Paragoniastrea australensis sits in Emily Bay on Norfolk Island and is one of our most recognisable bommies. While all looks reasonably calm during the day, at night, while you are sleeping, the surface of the coral colony seethes with millions of tiny tentacles busily reaching out to find food, while others aggressively ward off opportunistic interlopers.
Read MoreThe view across Emily Bay and Slaughter Bay’s contiguous reef at low tide. Quintal’s Passage can be seen as two parrallel lines of rocks. It runs from Emily out to sea.
Blasting a passage through the reef, Norfolk Island
We have shaped Kingston, Norfolk Island, to suit our own ends, whether it is by draining the swamp, undertaking major earthworks, or by using it for agriculture and grazing. Our interventions have placed the reef at risk. But simultaneously, the confluence of human activity and a unique natural environment have created a place of incredible significance, which deserves some special management to preserve all its facets.
Read MoreIs this Atramentous Necrosis? This January, examples of this disease are popping up across Emily Bay on Norfolk Island
Combine bacteria, fungi, and maybe a sponge = one toxic mess
This month, I have increasingly noticed a disease that is presenting differently to the white syndrome that we have sadly become used to seeing. With this disease the coral goes grey-ish black and sometimes looks like it is almost dissolving or melting away. The result is a tragedy for the coral. I talk to coral health researcher Associate Professor Tracy Ainsworth about what is going on.
Read MoreNorfolk Island’s inshore reef during low tide and at sunrise
A year in review – 2023 on Norfolk Island's reef
Sadly, the year didn’t bring any obvious improvements to Norfolk Island's reef in terms of reductions in incidences of coral disease, or runaway algal growth. And while some fish seem to have departed the scene, another species has re-established its home. Here’s a rundown of what I've been doing during the last four years of observations, and what I've seen happening on our reef in 2023.
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