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.

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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

Jul 28, 2025

Reef relief

Today, 28 July, is World Nature Conservation Day. After the dry 2024, Norfolk Island’s reef is looking healthier – a brief reprieve as less water - laden with nutrients - flowed into the lagoon. These photos show what’s possible. It’s a reminder that recovery is within reach – though renewed runoff could quickly undo the gains.

Jul 20, 2025

Emily Bay's big 'brain' coral

In Emily Bay, Norfolk Island, a single coral bommie – Paragoniastrea australensis – has stood for decades as a micro-reef, harbouring diverse marine life and local memories. Once photographed in 1988 and still thriving today, it remains a keystone of reef biodiversity and a living link between past and present.

Jul 14, 2025

Biodiversity matters

Over five and a half years of snorkelling Norfolk’s lagoon, we’ve documented 23 fish species not previously recorded in this area. Some are local ghosts, others climate migrants. These observations help us understand and protect what makes our reef so special.

Jun 17, 2025

Poop power

Not all poop on a reef is bad poop. In fact some kinds of poop can be a reef’s most important invisible engine. Fish poop, bird poop – even poop that gets eaten again by other fish – all of it keeps the ecosystem ticking over in a way that’s nothing short of extraordinary.

Jun 13, 2025

Glimpses of recovery: what the reef could be if we let it

Day 6 of this photo series from Norfolk Island coincides with the final day of the UN Ocean Conference in Nice. After a week of documenting decline, today’s post offers a different view – what reef recovery can look like when conditions improve. Drought in 2024 gave the reef a break, and the results were unmistakable: healthier corals, lower disease, and more fish. This is what’s possible if we act.

Jun 12, 2025

Warning signs: quiet and unnoticed collapse of two coral colonies

Day 5 of my blog series for the UN Ocean Conference: two long-lived coral colonies in Norfolk’s lagoon died quietly from disease. No drama – just slow collapse and overgrowth by algae. A reminder that not all reef losses are loud, but they are happening.

Jun 11, 2025

Warning signs: what Norfolk Island’s reef is telling us

Day 4 of a week-long photo series from Norfolk Island, shared during the UN Ocean Conference in Nice. Today’s post spotlights a Hydnophora pilosa colony where white syndrome appeared suddenly and spread quickly, taking out around a quarter of the coral. In the months that followed, algae quietly filled the gap – a subtle but telling shift from coral to algae that’s happening across the reef.

Jun 10, 2025

Warning signs: coral disease takes hold

In Day 3 of this blog post series, published while leaders gather at the UN Ocean Conference in Nice, we see Norfolk Island’s coral reef lagoon quietly delivering a stark warning: recurrent land-based pollution, coral disease, and delayed decisions are dismantling this ecosystem in real time.

Jun 9, 2025

Warning signs: coral growth anomalies – the slow cancers of the reef

Day 2’s post coinciding with the UN Ocean Conference looks at coral growth anomalies – sometimes called coral ‘cancers’. These slow-moving diseases quietly weaken coral colonies, making them far more vulnerable to storm damage and algal takeover. On Norfolk Island’s reef, I’ve watched this exact process play out over several years. This is how chronic stress silently dismantles coral ecosystems.

Jun 8, 2025

Warning signs: shifting baselines on Norfolk Island’s reef

Today is World Ocean Day — a timely moment to launch my week-long blog series on Norfolk Island’s reef. Each day this week, I’ll be sharing photo essays that document the slow but steady pressures reshaping this fragile reef. Today: how shifting baselines make us blind to what we’ve already lost.