Artificial rockpools in Bournemouth and the Isle of Wight have successfully attracted sea creatures, which have made them their home.
Scientists have hailed the discovery, saying the false crevices can be added to sea defences and other human-made coastline developments to create habitats for sealife such as crabs, barnacles, molluscs, small fish, sea squirts and seaweed.
The researchers, from Bournemouth University, installed 114 of the artificial rockpools – shaped like a typical bathroom sink – across three sites in 2020.
They have been monitoring the species that make use of the pools, comparing them with those using a seawall. Scientists counted 65 different species making use of the 45 artificial rockpools installed on a seawall at Sandbanks, including the protected native oyster Ostrea edulis. This compared with 40 species found in the cracks and crevices of the harbour wall.
“As our coastlines become more developed, marine species are seeing their natural habitats replaced by sea defences which are harder to colonise,” said Jess Bone, a PhD researcher at Bournemouth University. “Sea level rise is also compounding the problem and is squeezing their habitats into smaller and smaller spaces. We wanted to see if giving them more rockpools could offer them a lifeline in the face of these challenges.”
Rockpools are important habitats for small sea creatures because they retain water at low tide, with fish using them as nurseries because of the shelter and food provided. Mobile species, such as fish and prawns, can remain safely immersed when the tide goes out.
Bass – an important species for the local fishing industry – were also seen investigating the pools during high tide.
“At low tide, we found that the rock pools provided a haven for squishy species, like sea squirts and sponges, that would dry out on the seawall and not survive,” explained Bone. “Similarly, they helped delicate species, like bryozoans and some finer seaweeds, that would get bashed about by waves on the seawall and would not survive either.”
The scientists said they hoped more artificial rockpools would be made in future to help nature survive in developed environments.
“This project has shown how rockpools can help us to ensure nature can continue to survive in urban coastal spaces. They also give residents a chance to connect with nature, learning more about the wealth of wildlife just off the harbour’s edge and the role it plays in preserving our natural environment,” Bone said.