Day 12 – Menai Straits Dive, Take Two

13 November

Yesterday was tough. Calling off the planned dive at the Menai Straits in Anglesey wasn’t an easy decision, especially after hearing so many good things about the site from Clare and Leanne at Vivian Quarry earlier in the week. So today, we came back determined to try again.

This time everything went to plan. The traffic was light, the sun was out, and we made good time. Parking was a little tricky, and it took a short walk to reach our entry point. With the tide out, we had to cross a stretch of slippery rocks before finally getting to the water’s edge. We were lucky to have our friend Mia join us again to provide shore cover, and our SMBs made our position clearly visible to her and passing boats.

The Menai Straits is classed as a drift dive because of its strong tidal currents, which carry divers along at a steady pace. It’s a narrow body of water separating Anglesey from mainland Wales. Although it’s often called a river, it’s actually a sea channel, with many river-like features. The water temperature was a relatively warm 13°C, and the visibility was the best we’ve had so far on a sea dive during this trip.

We decided to swim against the current first, then drift back with it on our return.

As soon as we entered the water, we found ourselves above a small rocky outcrop followed by a sandy patch completely covered in hermit crabs, hundreds of them scuttling in every direction. Beyond that, the seabed sloped steeply down to a level area that revealed a beautiful garden of dahlia anemones. Their colourful tentacles were spread wide in every shade imaginable. Although dahlia anemones can be found all around the UK, we’d never seen so many in one place before. It was spectacular, one of the clear highlights of the day.

The site was alive with movement. We saw velvet swimming crabs, scorpion spider crabs, Leach’s spider crabs, and shore crabs in abundance. The variety of kelp and seaweeds, bladderwrack, sea lettuce, and others, created a dense underwater forest, offering shelter and food for countless species. The ecosystem felt incredibly healthy and thriving in this location.

We also spent time watching butterfish, the first we’d seen on this trip. They’re small, eel-like fish that move across the seabed with a distinctive, slithering motion. Their white-edged black spots made them easy to recognise.

By the end of the dive, we were so glad we’d decided to return. The Menai Straits proved to be every bit as special as we’d been told. The marine life was rich, diverse, and endlessly fascinating. We dived for around an hour, and although it was relatively shallow, it was full of interest from start to finish.

This isn’t a dive for beginners. The tidal currents, though predictable, are extremely strong, and it’s easy to end up far from where you planned, if you’re not careful. It’s a site that demands respect, good planning, and an honest awareness of your own limits.

For us, this dive was about slowing down, observing, and taking in the detail, the colours, the movement, and the hidden life of the seabed. It wasn’t about covering distance, but about appreciating the small, remarkable things that make each dive unique. A beautiful site, a rewarding dive, and a reminder that patience really does pay off underwater.

Yesterday we left the Menai Straits feeling disappointed. Today, we left extremely happy. Coming back was the right decision, and the dive was worth every bit of waiting and planning.