‘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.
An aatuti guarding his eggs, Norfolk Island
Aatuti are bold little algae farmers, but how does one of their farms begin? Over the past year, I have been following several coral patches as small white scars became algal footholds, then larger defended patches. I still cannot say what caused the first wounds, but the photo sequences show something fascinating: on a reef where algae is already gaining ground, even tiny changes on the coral surface can become part of a much bigger story.
Read MoreGreen moon wrasse, Norfolk Island, 17 July 2024
I’ve been photographing this guy, a green moon wrasse, since 2020, when he was a young adult just transitioning from being a female to a male. Green moon wrasse are said to live five to seven years in the wild, which means that our lovely old friend here could well be classified as an elder. This post is dedicated to this cheeky and inquisitive fish, the boss!
Read MoreMale birdnose wrasse, Gomphosus varius, Norfolk Island
All birdnose wrasses are born female but will change to males if the conditions are right. Its appearance changes radically throughout is lifecycle, from when it is a juvenile, through to being a female and then finally to being a male (known as sexual metamorphosis, or sequential hermaphroditism). For about three weeks you can see that transition taking place in the sequence of photos in this blog.
Read MoreBlue-barred parrotfish (Scarus ghobban), last seen in September 2021
In my ‘Year in review for 2023 on Norfolk Island’s reef’, published in December 2023, I made a few observations about the apparent disappearance of some fish species from Norfolk Island’s lagoons. I thought I would revisit these, principally because since December there has been so much additional fish activity here, with some exciting population increases and a few new species turning up.
Read MoreA bluestreak cleaner wrasse (Labroides dimidiatus) cleaning a coral sea gregory (Stegastes gascoynei)
Bluestreak cleaner wrasse, Labroides dimidiatus, are important critters on our coral reefs. These fish offer a swim-through full-body maintenance shop for other fish species – their clients – nibbling away dead skin and any nasty ectoparasites that might be living on their clients. There’s a lot to be learned about a reef from watching these busy little fish.
Read MoreA peacock damselfish – Pomacentrus pavo
Today I am featuring a fish called the peacock damselfish – Pomacentrus pavo. On our tiny reef, you can often count the fish of a particular species on one hand, and the peacock damselfish is a perfect example of this. Our last baby peacock damselfishes appeared in mid-February (2021), but this year juvenile fish for any of the species in our bays have been hard to find. Maybe they are later this year?
Read MoreAt this time of year, as the mating season begins, the delightful little Lady Musgrave blennies, Cirripectes chelomatus, change colour from dark inky blue black with a few barely visible red spots to a showy and vibrant mustard yellow.
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