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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
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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 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.

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Be like Senator David Pocock - wear a rashie

Sunbeams and sunscreens

December 19, 2022

What you need to know about Sunscreens

Did you know that sunscreen is highly toxic?

From 1 January 2021, Hawaii banned all sunscreens containing the reef-harming chemicals oxybenzone and octinoxate, and with good reason. This radical action was taken because unsafe sunscreens can, and have, caused ecological ruination to coral reefs.

Things you need to know:

  • Every person on the beach using an average dollop of sunscreen can contribute 36 g of sunscreen every two hours into the environment.

  • Thirty minutes after you’ve applied sunscreen it can be detected in your urine.

  • Even the sunscreen residue on your skin washes off in the shower and eventually finds its way into the environment.

  • Oxybenzone is an endocrine disruptor. In other words, it causes male fish to be less aggressive or less willing to mate. Where there are sufficient concentrations of oxybenzone in the water, it can prevent the process of sequential hermaphroditism – where a female fish turns into a male – from occurring. Or males may turn back into females. This results in fewer or no males for breeding.

  • The chemicals in sunscreen can cause the sterility of corals and fish, or for them to produce unhealthy offspring. They may look healthy, but sterile corals are known as coral reef zombies.

  • Oxybenzone can be toxic to the larval stage of fish.

  • When something happens to kill off the reef (increased sedimentation, disease, or bleaching, for example) a generally healthy reef will bounce back given the right conditions. However, reefs affected by the chemicals in sunscreen won’t necessarily have the capacity to do this.

  • Sunscreen is extremely toxic to lawns and is a herbicide. Some golf courses rule that there must be no sunscreen application while players are out on the greens because it will kill the turf. Likewise, it kills the underwater algae that is food for turtles.

  • Oxybenzone decreases the temperature at which corals bleach, and therefore decreases a coral reef’s resilience to climate change.

Do your bit to protect Norfolk Island’s corals

Check your sunscreen this summer and make sure it is reef safe. Even better, protect your skin without chemicals and use a #rashie. On Norfolk Island reef-safe sunscreens are readily available in our shops. (Prinke Eco Store Norfolk Bath & Body and from the chemist.)

Countries that have banned unsafe sunscreens include: Mexico, the USA (Hawaii, Key West, U.S. Virgin Islands, California), Bonaire, Aruba, Thailand and Palau. This list is growing as more places become reef-aware.

Choose your sunscreen wisely

In Ecosystem Tags corals, coral reef, coral reproduction, fish, Fish reproduction, Sunscreens, reef-safe sunscreen, Norfolk Island
← A Year in Review – 2022 on Norfolk Island's ReefThe black-mouthed tun snail – diary of an egg mass →
Featured
What Norfolk Island’s reef tells us about environmental blind spots
Apr 5, 2026
What Norfolk Island’s reef tells us about environmental blind spots
Apr 5, 2026

The Kingston dredging proposal on Norfolk Island raises a bigger question than dredging alone: how well do standard environmental assessment tools capture the real significance of a remote and unusual reef system like Norfolk Island’s?

Apr 5, 2026
Hammer coral time!
Mar 30, 2026
Hammer coral time!
Mar 30, 2026

Hammer corals have unique tentacles that are large, fleshy, and tubular; these terminate in a ‘T’-shaped, hammer-head or anchor. Beneath all these softly waving tentacles is an extraordinary skeleton structure, which helps define them as a large polyp stony coral.

Mar 30, 2026
Norfolk Island’s fishes: drifters, residents and the ones still missing
Mar 24, 2026
Norfolk Island’s fishes: drifters, residents and the ones still missing
Mar 24, 2026

Norfolk Island’s fish fauna reflects both connection and isolation. Some species may arrive from elsewhere as drifting larvae, some populations appear to persist locally, and some fishes known from islands on either side of Norfolk have still not been recorded here. This post looks at what old survey work, regional checklists and genetic studies suggest about that more complicated picture.

Mar 24, 2026
18 Jun 2025 (20)_crop.jpg
Mar 7, 2026
Alveopora or flowerpot coral – how to tell the difference
Mar 7, 2026

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.

Mar 7, 2026
Norfolk’s lagoonal reef – the 2025 report, in plain English
Feb 27, 2026
Norfolk’s lagoonal reef – the 2025 report, in plain English
Feb 27, 2026

We now have the 2025 Norfolk Island reef health report, so I’m taking the opportunity to translate it into plain English here. Sadly, it’s more of the same story in Emily and Slaughter Bays – a reef that can cope with some stress, but is being asked to cope with too much, too often.

Feb 27, 2026
Halimeda’s night shift – why this reef algae changes colour
Feb 20, 2026
Halimeda’s night shift – why this reef algae changes colour
Feb 20, 2026

Halimeda is a calcareous green reef alga that forms new segments overnight, shifts from white to bright green by dawn, then pales again as calcification begins. A quick look at one of the reef’s smartest algae.

Feb 20, 2026
Reef real estate – a bubble-tip’s six-year stand-off
Jan 11, 2026
Reef real estate – a bubble-tip’s six-year stand-off
Jan 11, 2026

Reef space is finite, and nothing ‘shares’ it politely. This short photo essay follows one bubble-tip anemone on Norfolk Island’s lagoonal reef as it holds a crater surrounded by Montipora. The coral builds a rim; the anemone holds the centre. Six years apart, and the argument continues.

Jan 11, 2026
A year in review – 2025 on Norfolk Island's reef
Dec 28, 2025
A year in review – 2025 on Norfolk Island's reef
Dec 28, 2025

Norfolk Island’s reef in 2025 – a year in review. From NOAA bleaching alerts and the UN Ocean Conference ‘Warning Signs’ series to post-drought coral recovery and a wet winter revealed in long-term rainfall records, this post captures the wins, losses, and shifting baselines beneath the lagoon. Includes reef photos, highlights from Reef Relief, and standout stories from 2025 – from coral health and disease to boxfish biomimicry, sea urchins, nudibranchs, and heat-stress signals in anemones.

Dec 28, 2025
Herbicides, heritage, and an inshore reef: what happens when land management meets lagoon health
Dec 15, 2025
Herbicides, heritage, and an inshore reef: what happens when land management meets lagoon health
Dec 15, 2025

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

Dec 15, 2025
Signs of bleaching – 8 December 2025
Dec 8, 2025
Signs of bleaching – 8 December 2025
Dec 8, 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 8, 2025

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