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Marine Life & Conservation

Diving with British Marine Life: The Grey Triggerfish



Part 2 of a new series by blogger Georgie Bull…

Before starting University last September, I dove Chesil Cove in the hope that I could get a glimpse of a triggerfish on the Royal Adelaide wreck. Grey triggerfish (Balistes capriscus) are seasonal visitors to our waters and are known to congregate on the wreck at a similar time each year. They are often fished off or battered by storms fairly rapidly, so sightings are temporally confined too.

 For anyone unfamiliar with Chesil, large pebble ridges create a wonderful pre and post dive work out for any diver keen enough to get in. Jon Bunker (Instagram: @jon_bunker) my Dorset dive buddy did a fantastic job of locating the wreck, and we had a very pleasant dive overall. Jon has invited me along on lots of his diving antics, and he’s the main reason I have so many photos to share.

On the dive we saw the likes of jewel anemones, congers, and a wonderful variety of wrasse. Without a trigger in sight, a couple of tompot blennies fighting one another became the main highlight. After the dive we spoke to a recreational angler on the beach, who mentioned he’d caught (and returned) a triggerfish while we were in the water. We were so close to a sighting!

Once I’d recovered from the pebble ridges and put my kit away, I accepted that I’d have to wait until next year.

Fast forward to a few weeks time, and the University of Plymouth’s Scuba Society were running their first shore club dive at Firestone Bay. I joined in, hoping to see a few different tunicates or echinoderms that I may not see so often in Lyme Bay. Instead, I was greeted with a large and relatively healthy triggerfish sat on the substrate. It turns out, I didn’t need to scale pebble ridges or use Jon’s impressive navigation skills to have an encounter with this species!


Triggerfish have defensive spines on their dorsal which are used to avoid predation, but also wedge themselves into crevices outside of harms way. Like their namesake suggests, the erection of their largest spine is triggered by the depression of a smaller spine closer to their head. Triggerfish are also known for aggressive behaviour, as they are particularly territorial over their nests.

Grey triggerfish are a Southern European species, and are valued by anglers both commercially and recreationally. This value has resulted in them being categorised as ‘vulnerable’ by IUCN. They are also the only triggerfish encountered in UK waters, with the other 39 species of triggerfish found typically in warmer waters.


In recent years, it’s been reported that grey triggerfish are becoming increasingly common in the UK. We have plenty of evidence to suggest that our oceans are warming, and we know from previous instances that migratory pelagic fish like the grey triggerfish are capable of shifting their distribution in response to environmental change.

In 1930, a grey triggerfish was recorded in St Malo, France; by the 1990s, they were being described as common in Jersey. In southern parts of the UK grey triggerfish sightings were unheard of too, up until the early 2000s. They are now regarded as common in some areas (like Chesil) at certain times of the year. It would be interesting to see this shift quantified more and understand if the increased catch rates may also be influenced by changing fishing methods and intensity.


Hear more from Georgie here:

Georgie is a Marine Biology and Coastal Ecology student at Plymouth University and an active diver in the South West of England. This year she will be completing the HSE Scuba qualification with the University in the hope that scuba will become part of her future career. She is particularly interested in native species and has a soft spot for elasmobranchs and molluscs.

Marine Life & Conservation

Meet Parpal Dumplin – Norfolk’s very own purple sea sponge named by local child



Ten years ago, in 2011, a new sponge species was identified in the North Norfolk chalk beds by Seasearch volunteer divers. In January 2021, the Marine Conservation Society’s Agents of Change project invited children in the Norfolk area to name the purple sponge.

Following lockdown, the judges thought that this would be an ideal time for school children to bond, while using their creativity – with no constraints. From home schooling children to entire classes, the panel of expert judges received a fantastic response with suggestions including Norfolk Purplish Plum and Purple Stone Sticker. All entries were carefully considered by a panel of experts, looking at the creativity, suitability and usability of each name.

It was unanimously agreed that the sponge should be named Parpal Dumplin. The winning name was suggested by nine-year-old Sylvie from Langham Village School, “because the sponge is purple and it looks like a dumpling”. The panel particularly liked that the spelling gives the sponge a strong connection to Norfolk.

The panel of experts deciding on the name included: Catherine Leigh, Education Adviser at Norfolk Coast Partnership, Annabel Hill, Senior Education Officer at Norfolk Wildlife Trust, Jenny Lumb, Teacher at The Coastal Federation, Nick Acheson, President at Norfolk and Norwich Naturalists Society and Claire Goodwin, Research Scientist at Huntsman Marine Science Centre and internationally renowned sponge specialist. At the meeting, the panel was supported by Seasearch East Coordinator, Dawn Watson, who recognised this sponge as special over a decade ago.

Claire Goodwin, internationally renowned sponge specialist, says: “Dawn and Rob invited me to join a Seasearch survey of the east coast, including the Cromer Shoal Chalk Beds. Dawn introduced me to a purple sponge she had noticed on the chalk reefs. We took samples, and believe it to be a species new to science, in a sub-genus of sponges known as Hymedesmia (Stylopus).”

We need to look at specimens deposited in museums to understand how many different Hymedesmia (Stylopus) species exist in the UK and how they differ from this new species. The Agents of Change naming project has given the sponge a common name that we can use until it has a scientific one.  I loved seeing all the creative suggestions.

Sponges help to keep seawater clean by filter feeding, consuming tiny particles of food that float by. There are over 11,000 different species globally and our purple one is ‘encrusting’, meaning it adopts the shape of whatever it covers. It lives in Cromer Shoal Chalk Beds Marine Conservation Zone, a precious area of local seabed that needs to be taken care of.

Jenny Lumb, Teacher at The Coastal Federation, said: “Naming the purple sponge has been a fun way for children to find out about the fascinating life hidden beneath the waves. It’s amazing to be given the chance to name a species that scientists and divers will use for years to come! The children are so fortunate to have the MCZ on their doorstep. They had a great time on the beach discovering some of the life there, collecting litter and finding out about this special coastal area. I am sure the children will continue to enjoy and care for the coastal environment into the future.”

Catherine Leigh, Education Adviser from the Norfolk Coast Partnership said: “It was a pleasure to help decide on the sponge’s name from so many fantastic suggestions submitted and I hope it will inspire people to find out more about all the incredible inhabitants of this Marine Conservation Zone on our Norfolk coastline.”

Hilary Cox, Agents of Change Norfolk Coordinator, said: “Parpal Dumplin is a great choice by the decision panel of specialists:  a local Norfolk name for this newly found species in North Norfolk’s Marine Conservation Zone.”

Annabel Hill, Senior Education and Engagement Officer at Norfolk Wildlife Trust said: “Wonderful to be involved in the process of naming a new species of sponge, found in Norfolk from a range of fantastic creative names suggested by local school children”.

You can find out more about the purple sponge, and the search for its name, by watching this animation: The seabed is a fun place to be!

For more information on the work of the Marine Conservation Society visit their website by clicking here.

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Marine Life & Conservation

Save the Sharks, Save the Planet (Watch Video)



In 2020 Oyster Diving helped to train Toby Monteiro-Hourigan to become one of the youngest (12 years old) Master Scuba Divers ever. You can read his story here.

Toby has just completed this amazing ‘David Attenborough’ project video for his school on shark conservation. Please watch and share as it really is an eye opener in why we need to protect these incredible creatures.

Thanks to Toby and for letting us share this video.

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Explore the amazing triangle of Red Sea Reefs - The Brothers, Daedalus and Elphinstone on board the brand new liveaboard Big Blue.  With an option to add on a week at Roots Red Sea before or after. 

Strong currents and deep blue water are the catalysts that bring the pelagic species flocking to these reefs. The reefs themselves provide exquisite homes for a multitude of marine life.  The wafting soft corals are adorned with thousands of colourful fish. The gorgonian fans and hard corals provide magnificent back drops, all being patrolled by the reef’s predatory species.

£1475 per person based on double occupancy.  Soft all inclusive board basis, buffet meals with snacks, tea and coffee always available.  Add a week on at Roots Red Sea Resort before or after the liveaboard for just £725pp.  Flights and transfers are included.  See our brochure linked above for the full itinerary.

This trip will be hosted by The Scuba Place.  Come Dive with Us!

Call 020 3515 9955 or email

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