• Home
    • Algae
    • Corals
    • Eels
    • Everything Else
    • Kingston, Norfolk Island
    • Nudibranchs, Sea Slugs and Flatworms
    • Octopuses
    • Out On A Swim Index
    • Reef Fish
    • Sharks
    • Sea Anemones
    • Sea Stars
    • Sea Urchins and Sea Cucumbers
    • Turtles
    • Underwater
    • Videos
  • Out on a swim - blog
  • About
  • Contact + Subscribe
Menu

Norfolk Island's Reef

Discover a fragile paradise – Norfolk Island's beaches, lagoons and coral reef
  • Home
  • Explore
    • Algae
    • Corals
    • Eels
    • Everything Else
    • Kingston, Norfolk Island
    • Nudibranchs, Sea Slugs and Flatworms
    • Octopuses
    • Out On A Swim Index
    • Reef Fish
    • Sharks
    • Sea Anemones
    • Sea Stars
    • Sea Urchins and Sea Cucumbers
    • Turtles
    • Underwater
    • Videos
  • Out on a swim - blog
  • About
  • Contact + Subscribe

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.

Surge wrasse, Thalassoma purpureum, Norfolk Island

Meet George, the surge wrasse

March 13, 2024

Meet George, the surge wrasse. In fact, here on Norfolk Island, for some weird reason, they are all called George and have been for as long as I can remember. I’ve no idea why, but I do recall asking someone, many years ago, what kind of fish this purple, turquoise and pink guy was and I was told, ‘Oh, that is George!’ And so the name stuck!

George is also known as a green-blocked wrasse, purple wrasse or red and green wrasse, and more formally as a Thalassoma purpureum.

These guys are insanely, eye-achingly colourful, so I decided they were worthy of a photo dump on these pages. The Georginas can be seen towards the bottom of the photo gallery, and while more subtle in their colouration they are still very pretty.

Here are some quick facts about George and his relatives:

  • Surge wrasse are widespread, ranging from the southeast Atlantic, across the Indian Ocean and into the Pacific.

  • They love to hang out on rocky shores and coral reefs where there is plenty of heavy wave action.

  • The largest males can grow up to 46 cm in length and weigh about 1.2 kg.

  • George is a carnivore. He likes to eat sea urchins, crabs, molluscs, worms and other invertebates, and even small fish. You can see a surge wrasse feeding on fish in the video, ‘Lifecycle of the mouthbrooding Norfolk Cardinalfish, below.

  • They are protogynous hermaphrodite, in that females change sex to become males.

  • It is a pelagic spawner. The eggs and sperm are broadcast into the surface waters of the open ocean.

  • They are thought to live for ten years in the wild.

The surge wrasse’s protractile mouth juts outwards (Norfolk Island)

Surge wrasse are members of the wrasse family (Labridae) many of which are brightly coloured. I have noted 22 species of wrasse living inside our lagoons so far. If you include parrotfish (Scaridae), which are traditionally referred to as a separate family, but are now often treated as wrasse, there are an additional five species that I have recorded here.

Like many members of the wrasse family, they have protractile mouths, with separate jaw teeth that project forward, and fleshy lips.

References

  1. iNaturalist

  2. Wikipedia, Surge wrasse

  3. Wikipedia, Wrasse


View fullsize 9 Mar 2024 (185)_crop.jpg
View fullsize 9 Mar 2024 (186)_crop.jpg
View fullsize 25 Sep 2023 (70)_crop.jpg
View fullsize 10 Mar 2024 (8)_crop.jpg
View fullsize 14 May 2023 (150)_crop.jpg
View fullsize 9 Mar 2024 (181)_crop.jpg
View fullsize 29 Jan 2023 (191)_crop.jpg
View fullsize 29 Jan 2022 (97)_crop.jpg
View fullsize 10 Mar 2024 (5)_crop.jpg
View fullsize 10 Mar 2024 (4)_crop.jpg
View fullsize 8 Apr 2023 (108)_crop.jpg
View fullsize 11 Jun 2023 (32)_crop.jpg
View fullsize 25 Dec 2021 (23)_crop.jpg
View fullsize 5 Feb 2021 (36)_crop.jpg
View fullsize 25 May 2021 (88)_crop.jpg
View fullsize OI001108_crop.jpg
View fullsize 7 Jan 2021 (192)_crop.jpg
View fullsize 14 Nov 2021 (244)_crop.jpg
View fullsize 17 Oct 2021 (83)_crop.jpg
View fullsize 7 Aug 2022 (8)_crop.jpg
View fullsize 22 Jan 2023 (124)_crop.jpg
View fullsize 17 Apr 2023 (56)_crop.jpg
View fullsize 10 Jun 2023 (64)_crop.jpg
View fullsize 7 May 2022 (107)_crop.jpg

← Blasting a passage through the reef, Norfolk IslandNorfolk Island reef's autopsy reports →
Featured
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
Nature is my teacher
Dec 3, 2025
Nature is my teacher
Dec 3, 2025

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.

Dec 3, 2025
Reef grief: what dredging has done to other reefs
Nov 30, 2025
Reef grief: what dredging has done to other reefs
Nov 30, 2025

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 30, 2025
To dredge or not to dredge? The Kingston Pier channel project
Nov 20, 2025
To dredge or not to dredge? The Kingston Pier channel project
Nov 20, 2025

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 20, 2025

Latest Posts

© 2026 All rights reserved.