Why are native oysters considered superheroes of the sea?

New Home For The Superheroes Of The Sea
Moving native oysters from Scotland to the Solent

Dr Luke Helmer, Blue Marine Foundation’s Restoration Science Officer, has spent the past few years creating the first two native oyster restoration reefs on the Solent. This marks both a substantial milestone for the project, which began in 2015, and a leap forward for an iconic species that has all but disappeared in the area. Blue Marine is working alongside wider UK & Ireland and European networks to restore the native oyster in its natural range. If you are interested in supporting some of their UK based work, please get in touch.

This is Luke’s story

Having spent my childhood and academic career on the South Coast, I have developed a strong connection with the area and the natural beauty above and below the water. People often ask how I ended up working on oysters and the honest answer is: “I was in the right place at the right time — just kind of fell into it, I guess. Then I worked hard, so I am still riding that wave.”

It is probably the sheer number of benefits that they can provide to nature and communities that intrigues me the most. From their ability to filter vast quantities of water a day, to supporting hundreds of species across their natural range, these unassuming creatures are certainly superheroes of the seas. Their amazing capabilities are also what make the dramatic decline of many oyster species around the world even more heart-breaking: humans have essentially removed the kidneys from the ocean and are now paying the price.

We have been working with native oysters for several years and knew that scaling up our operation was inevitable. Having seen first-hand how reefs are built from shell and gravel in the US and Australia, I knew that this was going to be no mean feat. We are lucky to have a fantastic working group of stakeholders in the Solent, so I was confident that it was possible for us to come together and recreate these on our patch on the south coast of the UK.

Creating the first oyster restoration reef was a monumental undertaking. Site selection, licence application, and organisation for creating a reef in one of the busiest waterways in the UK certainly caused a few headaches, but after a long arduous process everything fell into place and we had sign-off from all the people we needed.

It was a surreal experience, being collected by the small work boat to head out into the harbour that I have been into so many times before. This time was different. I knew something big was happening. Approaching the barge set-up I felt a mixture of anticipation and excitement — the big toys were out, and they were being used to build an oyster reef for us!

Watching the first drop of shell and gravel to form the base of the reef, and mimic the seabed, was exhilarating. In a year when anything that might go wrong had done, this was the first time that everything went to plan, which meant we could go full steam ahead with the rest of the reef creation.

The second day of the seven-day programme allowed us all to see the entire process from start to finish. The morning began in the dark at 04:30, when I met BLUE’s Senior Project Manager, Jenny, and freelance camera operator Matt at Fawley waterside to witness the first step of the process — loading the barge. This was a swift operation, which allowed us all to get overly excited about the drone shots that Matt was getting. It was then a race: us by land, the ‘would-be’ reef by sea… the reef, however, didn’t need to grab breakfast on the way. Watching the second deployment onto the seabed, we knew we were in safe hands and could leave the operators to do their thing.

This left Jenny and me free to head up to Scotland to meet our colleague Alex and collect the first batch of oysters that would make their new home on the reef. Reversing a large van over soft sand and gravel is certainly an interesting experience, but after a short while the van was 15,000 oysters and half a tonne of shell heavier. Luckily we avoided any sinking dramas, and were soon on our way back down south, with 12 hours of Alex’s road trip singing ahead of us.

Unloading the van at 01:00, knowing that we were up again in a matter of hours to give them all a thorough clean made us work quickly, to get as much sleep as possible. To our relief, we arrived on site and were joined by an army of helpers. All the oysters had to be checked and sorted before heading to the spa for a bleach bath, to make sure it was just the oysters that we threw out over the reef.

The final day of operations was upon us. Our reef was ready, GPS positions were plugged in, 15,000 oysters had been cleaned and sorted. A local fisherman was on hand, ready to take us to site, and cameras were at the ready. And — like that — it was all over. After all the planning, the countless hours of work to get to this point, the actual deployment of oysters takes but a matter of minutes, even when accommodating all the angles the film crews wanted to capture. The reef in Langstone Harbour was the first in what we hope will become a network of reefs across the Solent. More oysters have been added over time thanks to the continued support of the project, but hopefully within the next few years we will start to see natural settlement, and the populations will become self-sustaining.

We have now grown the project to include a second reef at Swanwick bend in the River Hamble in Hampshire - one of Britain’s busiest waterways. 30,000 oysters have been transferred from South Wales to seed in the new habitat created in the River Hamble. In order to create the perfect environment for these oysters, 2,500 sq m (27,000 sq ft) of shell and gravel was laid as the foundation for the reef, over twice the size of the site in Langstone Harbour.

Undertaking the creation of a new oyster restoration reef in such a busy waterway was not easy. Louise MacCallum, Solent Project Manager for Blue Marine, said: “This new restoration reef has taken more than a year to plan.”

“As well as creating a perfect home for 30,000 oysters, it has also been critically important to ensure that our operations do not affect navigational safety for the many people who enjoy boating and water sports on the river.”

Having overcome the herculean task of navigating both the needs of the molluscs and those who use the river on a daily basis, the reef will hopefully be a beacon of biodiversity in the area.

"This reef deployment is another significant step forward in re-creating the sub-tidal oyster reef habitat that has been all but lost in the Solent and across Europe.” said Joanne Preston, reader in marine ecology and evolution at the University of Portsmouth.

"We hope this reef creates a tipping point, kick-starting a population of native oysters that builds over several generations and provides offspring that will spill over and populate other areas.”

"We also predict strong biodiversity gains and water quality improvements, which we will be monitoring over the next five years."

The Langstone Harbour reef has already seen tremendous success in bringing back native species, so we expect the River Hamble reef to achieve the same results. As Louise MacCallum said: "The Langstone reef has already attracted a wealth of marine fauna, including cuttlefish, catsharks and even seahorses.”

"It is exciting to see what kinds of marine creatures our new reef will attract in the River Hamble."

The restoration and recovery of the European native oyster is not going to be quick. It is not going to be easy and it is not going to be smooth sailing. But the team in the Solent, and others across Europe, are in it for the long run.