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.
Read MoreSlaughter Bay, Norfolk Island, March 2020
From 'Watch' to 'Warning'
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.
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.
Read MoreFeisty 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 MoreThis Acropora colony on Norfolk Island’s reef was photographed in 2021. Today it is no longer there. Weakened by disease, it was destroyed by a storm surge two years later, in December 2023
Then and now – shifting baseline syndrome laid bare
If disease were spreading through our native forests, if our trees were developing strange growths that hollowed them out, making them brittle in the face of each passing storm, would five years have slid by with the problem worsening by the day? That is exactly what is happening on Norfolk Island’s reef. Slowly, insidiously, it is dying and turning to slime.
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 MoreExtensive area of acropora coral affected by white syndrome on Norfolk Island’s reef
Taking stock. Which way from here?
CSIRO are on Norfolk Island this week to present the findings of their report into water quality. As our Administrator, George Plant, says: ‘What the data shows us is that the quality of ground and surface water entering Emily and Slaughter Bays often contains high levels of contamination ... The health of the Emily and Slaughter Bay reef will continue to decline if we do not improve water quality.’
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 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 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 MoreAcropora coral, Norfolk Island, 14_StairwayReef, 14 November 2021
The journey from coral reef to rubble
For two years, I have stopped by and photographed this beautiful Acropora coral formation in Emily Bay on Norfolk Island. In my database for this colony, I called the folder 14_StairwayReef; 14 for the geographic location on a map, followed by my romantic name for it. Today it is just so much rubble.
Read MoreWhite syndrome on a Hynophora pilosa colony, Norfolk Island, 23 November 2023
The spatiotemporal dynamics of a coral disease
A pictorial study of the spread of white syndrome, over time, in a Hynophora pilosa colony on Norfolk Island. This beautiful coral colony is in the middle of the channel that runs between the contiguous Emily and Slaughter Bays, in Norfolk Island’s inshore coral reef lagoon. It’s one of my favourite places to pause and admire the scenery, when I’m out on my swim.
Read MoreAcropora corals, Norfolk Island’s reef
Brown? Yes. Boring? Definitely not!
Norfolk Island’s reef is one of Australia’s most southerly. It isn’t showy like the Great Barrier Reef, and I often hear the comment that it is a little dowdy – boring and brown. I’m here to tell you that it is anything but.
For this little photo essay I randomly selected just a handful of my many ‘boring, brown’ coral images to demonstrate my point. I barely scratched the surface of my photo library, yet I think you will agree, the diversity is just amazing!
Read MoreEmily Bay, full moon rising, by Norfolk Island photographer Joelene Oliver
Full moon, low tides and Norfolk Island’s reef
With the low, low tides associated with a full moon, the bays on Norfolk Island are like a huge, calm swimming pool, giving us some great snorkelling opportunities. These low tides should also let us view the causeway, which will no doubt be exposed too. This post explores these opportunities as well as what the low tides mean for corals. Read more in this fact packed blog post.
Read MoreCrustose coralline algae, Norfolk Island
Pretty in pink – the real coral reef builders
Animal, vegetable or mineral? What are crustose coralline algae? Are they important? What role do they play on our coral reefs?
There’s a lot to learn about coralline algae. For a humble lifeform, they really pack a punch.
Read MoreA sea mat on the edge of the reef where the waves break, Norfolk Island
A tale of two corals
My March focus on Norfolk Island’s reef could almost go on for a full year, there’s so much to write about. But time dictates, so I will confine my efforts to one concentrated effort of randomness! Randomness, because there has been no plan to my posts. They have evolved as the month has progressed. Today I highlight two very different corals commonly seen, but not necessarily common.
Read MoreBubbles of oxygen forming on algae, photobombed by a tiny sea slug, sp, Elysia
Bubble and fizz – a quick guide to coral reef chemistry
March is often the warmest month on Norfolk Island’s reef, so it's no surprise that the algae are very busily photosynthesising and flourishing. Yesterday, I noticed that the algae had created a thick carpet of bubbles. As I swam my face was gently brushed by thousands of tingling bubbles, fizzing to the surface. It was quite a sight. And a rather weird sensation. So what is going on here?
Read MoreAcropora coral overgrown with algae, Norfolk Island
We can't say we weren't warned
Today’s post for the March focus on Norfolk Island’s reef is a letter. Just that, and nothing more. The authors of this letter have very generously given me permission to reproduce it here. In it, Dr Kellie Pendoley and Dr Martin Goldsmith warn us about the future of Emily Bay. Written nearly eight years ago they give the coral reef habitat five to ten years before it is gone as we know it.
Read MoreLow tide at Cemetery Bay, Norfolk Island
A rare gem – Cemetery Bay, Norfolk Island
No focus on Norfolk Island’s reef would be complete without a look at Cemetery Bay. It’s worth strolling along this beautiful beach at low tide. It is the island’s dog beach, so you will see plenty of locals out walking here, but better still is what you can see in the water – healthy corals happily growing right up to the beach.
Read MoreJust some of our beautiful corals on Norfolk Island
A boring, brown reef?
People say that Norfolk Island’s reef is rather boring and brown when compared to the Great Barrier Reef. While it may not be as colourful, I think you have to agree that it is anything but boring brown!
Read More