Black Blenny - a new record for Norfolk Island

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.

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DAY 25 – MARCH FOCUS ON NORFOLK ISLAND’S REEF

Today’s post is to highlight how little we still know about Norfolk Island’s reef.

Below is a copy of the Australian Fishes journal post about new fish sightings on Norfolk Island. You can find the original post here: Black Blenny - a new record for Norfolk Island

Author: Mark McGrouther, Senior Fellow at the Australian Museum.

This small fish in the image above was photographed by Susan Prior (@susanprior) in Slaughter Bay, Norfolk Island. Susan couldn’t identify the fish so she uploaded the observation identified simply as a ‘Ray-finned Fish’ to the Australasian Fishes Project.

Francois Libert (@francoislibert) subsequently correctly identified it to family, then Malcolm Francis (@francism) tentatively identified it as a Black Blenny, Enchelyurus ater. Malcolm tagged me for my input, so I referred the observation to Australian Museum Senior Fellow, Doug Hoese who confirmed Malcolm’s tentative identification.

Malcolm was particularly interested in Susan’s observation because for some years he has maintained a checklist of the coastal fishes of Lord Howe, Norfolk and Kermadec Islands. Malcolm noted that the Black Blenny had not previously been recorded from Norfolk Island.

This observation highlights the power of citizen scientists working with professional ichthyologists to achieve important outcomes. It also illustrates the fact that users shouldn’t be afraid to upload observations of fishes that they can’t identify. Most of the time someone will step up to the plate with an identification.

Thanks to everyone involved in bringing this new record to light.

Comments to the above post

Posted by francism: This is not Susan Prior's (@susanprior) first new fish record from Norfolk Island. In the past month alone she has recorded three new fish records for the island that I will be including the next time I update the checklist. A big thank you to Susan for her excellent observations! Thanks also to my Australian fish colleagues, Doug Hoese and Mark McGrouther (@markmcg) for their help with identification.

Susan's other recent new fish records are the sabre squirrelfish (Sargocentron spiniferum) and dusky wrasse (Halichoeres marginatus).

Posted by markmcg: Thanks for your excellent comment @francism.

Susan has made a terrific contribution to our knowledge of the fish fauna of Norfolk Island. She has found a total of eleven new fish records from the island (list below). For more details, see her blog post.

Banded sergeant - Abudefduf septemfasciatus
Wartylip mullet - Crenimugil crenilabis
Marbled parrotfish - Leptoscarus vaigiensis
Dot-and-dash Goatfish - Parupeneus barberinus
Bluebarred Parrotfish - Scarus ghobban
Palenose parrotfish - Scarus psittacus
Yellowtail barracuda - Sphyraena flavicauda
Hornpike Long Tom - Strongylura leiurus
Dusky wrasse - Halichoeres marginatus
Sabre squirrelfish - Sargocentron spiniferum
Black Blenny - Enchelyurus ater

Apr 5, 2026

What Norfolk Island’s reef tells us about environmental blind spots

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Hammer coral time!

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Mar 24, 2026

Norfolk Island’s fishes: drifters, residents and the ones still missing

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 7, 2026

Alveopora or flowerpot coral – how to tell the difference

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.

Feb 27, 2026

Norfolk’s lagoonal reef – the 2025 report, in plain English

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 20, 2026

Halimeda’s night shift – why this reef algae changes colour

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Jan 11, 2026

Reef real estate – a bubble-tip’s six-year stand-off

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.

Dec 28, 2025

A year in review – 2025 on Norfolk Island's reef

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 15, 2025

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

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

Dec 8, 2025

Signs of bleaching – 8 December 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.