‘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 blog is rated in the Top 20 Coral Reef Blogs in the world.
A 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 MoreLow tide at 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
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 MoreHealthy montipora coral, Norfolk Island
Today’s focus on Norfolk Island’s reef is a photo essay. This series of photographs taken over the course of a year demonstrates how disease affects a montipora coral bommie by gradually killing the coral and creating an environment that allows algae to gain a foothold and to eventually take over.
Read MoreA common view of an aatuti as you swim into its territory!
One species that is doing remarkably well on Norfolk Island’s reef as it inexorably transitions from coral-dominated to algal-dominated is the banded scalyfin, Parma polylepis, which is unsurprising as their main food source is algae. The downside is they harass and bully all the other species that come anywhere near their territory, to the detriment of our biodiversity. Find out more here.
Read MoreTiny shells collected from the beach, Norfolk Island 1990s
On Norfolk Island, Australian Marine Parks recently issued a no-take area in our coral reef lagoon habitats. My hope is that with these bans in place, in addition to curbing runaway algal growth, there will be an improvement across the reef ecosystem in a number of different species, with subsequent knock effects for others, including for our molluscs, wrasse and octopus species.
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 MoreThe creek by the Salt House into Emily Bay
When Lt Philip Gidley King first arrived on Norfolk Island on 6 March 1788, the Kingston area was a swamp entangled in almost impenetrable vegetation. Chimney Hill created a natural stone barrier preventing water from draining into Emily Bay. In 1789, a channel was cut through the swamp, to the north of Chimney Hill and out into the bay. From this moment on the coral reef was compromised.
Read MoreA wayward scissortail sergeant (Abudefduf sexfasciatus)
Swimming has been with me all my life. It provides me with three wondrous things: time, space and connection. Time to myself. Time to contemplate, reflect, explore, see and watch. An endless, fathomless space where there is no one else but my own thoughts. And a connection with our natural world – something that is so important but so often not understood as being essential to our health and wellbeing. Read more here …
Read MoreFrom front to back: raccoon butterflyfish; blackback butterflyfish; three-striped butterflyfish Back right: Threadfin butterflyfish
Butterflyfish are ‘corallivores’, that is, they feed mainly on coral polyps and the energy-rich mucous that these produce. Corals also make a great place for butterflyfish to shelter in and under. Without healthy corals, then fish like these will become more and more scarce.
Read MoreThe black-mouthed tun snail as it clambered over the reef
When I took my first photographs of the live black-mouthed tun snail (Tonna melanostoma) and posted them on iNaturalist, I had no idea that there were no other – as in none, zip, nada – images of it in the public domain; just one of a broken shell that is housed in the Auckland Museum. This is my featured image for 3 March.
Read MoreBait fish, Emily Bay, Norfolk Island, September 2020
For 2 March I've chosen to feature a ball of bait fish photographed in September 2020. There is something awe-insipring about being encircled by a huge seething mass of tiny fish all moving in unison. It takes your breath away. The question is, where have these bait balls gone?
Read MoreHealthy montipora coral on Norfolk Island’s reef
After three years of observations, I have a unique library of some 80,000 images recording life in Norfolk Island’s lagoons. So I thought it would be worth spending the month of March looking back to see what has changed in that time and what hasn’t. Each day I will feature a different image. For 1 March I have picked a simple brown coral – a plate coral from the genus montipora. Read on to see what is happening to our montipora now.
Read MoreWhite-speckled sea hare, Aplysia argus, in Emily Bay, Norfolk Island
Sea hares, little submarine shreks that lumber their way slowly around intertidal zone are fascinating, and quite common, although most people won’t have heard of them. Their appetite for algae makes these a really useful species to have in our bays, along with parrotfish, sea cucumbers and sea urchins. And it is the algae that dictates their colouring.
Read MoreHannah and Trish with Doris
This morning marked the end of a four-month journey for Doris the green sea turtle. From a sick, emaciated turtle with lesions across her shell, and covered with an unhealthy growth of algae, she has been transformed to glossy beautiful health. Hannah slid Doris over the side of the boat and back into the bosom of the ocean, her home. We’ll miss her, but as she swam away, our hearts sang, too. She’s back where she should be.
Read MoreHornpike long tom - Strongylura leiurus
It only takes your observation of one little fish out of its previously understood ‘comfort zone’ to add to a body of evidence that may prove, or disprove, scientific theories, which may then in turn be used to inform government policy on climate change, preserving the environment, and much more. That is citizen science at work. And it can be powerful and fulfilling.
Read MoreLone Pine photographed from Emily Bay, showing the freshwater layer caused by innundation from the creek.
It’s always a good time to take stock of the year that was, so I’ve been thinking about what 2022 held for Norfolk Island’s reef. La Niña superimposed on La Niña has meant copious rainfall and a lagoon under stress: more algae, more coral disease, fewer fish. Here’s a quick run down of what has been happening on our reef during 2022.
Read MoreBe like Senator David Pocock - wear a rashie
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.
Read MoreBlack-mouthed tun snail, Tonna melanostoma
The black-mouthed tun shell’s egg mass is photographed almost daily over a period of six weeks, from the morning they are laid until becoming dislodged from their rock after a period of big swells and storm surges.
Read MoreIt’s been widely reported since the 1960s, at least, that nutrient-laden water flowing out the channel into Emily Bay is having a detrimental effect on Norfolk Island’s reef – a reef where it is thought that as much as 30 per cent of the corals are as yet undescribed. Are we going to do something about it before the reef has gone? Because, quite seriously, we have no time left to lose.
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