Visitors to the Welsh coastline include dolphins, porpoises, basking sharks, Atlantic grey seals and leatherback turtles. Pembrokeshire and Ceredigion are seen as an area of international importance for bottle nosed dolphins, and New Quay in Cardigan Bay has the only summer residence of bottle nosed dolphins in the UK.
Pembrokeshire has its own Marine Nature Reserve at Skomer Island, one of only a handful of underwater reserves in the UK.
The diving around Anglesey is some of the best in the UK.
- Skomer Island - a Dutch coaster, The Lucy, which sank in 1967 and is the most dived upon wreck in the area with its deck at 32 metres and dropping down to 40 metres.
- Dead Eye Wreck which lies along the rocks the other side from The Lucy at a place called The Neck, east of South Haven. She is spread over a large area and tides are slack near the cliffs. Makes for a good second dive after the Lucy. Depths are around 8m – 15 meters. In the bay to the left, as you face the island, you will usually see seals. They can be quite playful, especially the young pups.
- The wreck of The Missouri, at a depth of 14 metres in Trearddur Bay, was the largest vessel ever wrecked close inshore on the west coast of Anglesey. The Missouri was 5,146-tons and ran ashore at Porth Dafarch on 1 March 1886 while carrying a mixed cargo of cattle, hides, cotton and flour. The Missouri was a large iron screw steamer but had four masts to provide sail assistance.
- The "Telephone Cables" under the Menai bridge is anothet popular dive. In the shallower areas, the rocks are almost totally covered in sponges and anemones. The most commonly seen fish are two-spotted gobies, short-spined sea scorpions and butterfish.
|Diving season:||March to April|
|Water temperature:||Winter 7C (45F)|
|Summer 15C (59F)|
|Air temperature:||Winter 6C (43F)|
|Summer 18C (64F)|