Earlier this year, one of my good friends was out walking along the rockpools here on the Cornish coast when he – quite literally – stumbled across his very first hair curler sea slug. This wasn’t only a first for him, but a first for anyone here in the UK.

This species of nudibranch is more commonly found around tropical waters of the Mediterranean, but in the last few months they have become very common here in Cornwall.

You’ve probably heard of the rainbow sea slug, Babakina Anadoni – one of the most beautiful animals on the planet and another sea slug not native to the UK. But for the last few years, they have been found in rock pools once again, here in Cornwall.

It’s very exciting for people like me who like to go out and explore the rock pools. But it’s also a bit concerning as these animals are not native to our waters. But they are clearly finding it comfortable here enough to be found, even in the winter. And this could just be a symptom of bigger changes at play…