Snorkelling: A Swimmer’s Guide

It's time to embrace not being the only living creature in the water

Whether in lake, river or sea, outdoor swimmers are perfectly placed to enjoy and learn about life under the waterline – and this is a great time of year to start. The OSS’ Beth Pearson takes beginners tips from ecologist and diver Martin Stevens, who posts his snorkel escapades as @sensoryecology

Why do it?

For regular swimmers of sea, lake or river, taking more time to look around or down to watch wildlife seems a natural progression.  “I think the benefit of looking beneath the water is connecting with nature and the amazing animals and habitats that we have,” says Martin. “By exploring underwater you can engage with a whole other world, ranging from seagrass and colourful patches of seaweed, to kelp forests, and the myriad of animals that live there.” 

What can you see?

One of the singular attractions of snorkelling is seeing the familiar in a new way, so spotting a rare kind of sea slug or anemone isn’t always necessary to feel a good time has been had. It could be a familiar limpet dramatically departing from all the associations of its name to slowly travel across a rock as it grazes between the tides, or a common beadlet anemone you’ve seen a thousand times before in rockpools fully extended on the underside of a rock that you’d never have spotted from the seashore. 

“I know the south west of England best and it really depends on the season, but you can expect to see things like starfish, several species of jellyfish, and sea anemones like snakelocks,” says Martin.  “In summer, shoals of sand eels and bass, and if you’re lucky cat sharks or cuttlefish – and much more! Different times of year vary a lot in terms of species. Summer has the most, with shoals of fish and jellyfish, but some species like anemones and starfish are about all year. Spring tends to have the most vibrant colours and freshest seaweed.”

When to do it? 

“Predicting visibility seems a bit of a dark art,” says Martin. “The main thing is calm conditions but things like plankton blooms can have a big impact. Early spring, when the winter storms have passed, is often the clearest. Summer can be amazing, and a lot warmer, but tends to have plankton and other things clouding the water a bit. On the other hand, that can bring in other creatures to see.”

Photo: Martin Stevens @sensoryecology

Different times of year vary a lot in species – summer has most, with shoals of fish, jellyfish, but some species like anemones and starfish are about all year. Spring tends to have the most vibrant colours and freshest seaweed.

Where to do it?

“To find out good snorkelling spots, local knowledge and guides are ideal, especially as some places can have variations in currents and waves,” says Martin. “Some companies run snorkel safaris – these can be a good way to explore, especially if people are a little nervous about exploring a new place. A good surf forecasting app can be good to predict calmer conditions and knowing the effect of wind direction.

“In the UK, it’s actually hard to beat Falmouth for the diversity of creatures and environments, from kelp forests to seagrass patches and sandy stretches, and lots of colourful weed and creatures. Helford River is also terrific, with large areas of seagrass, and I’ve had some amazing experiences there with cat sharks and cuttlefish.”

Calm bays with rocky areas that are good for rockpooling at low tide are generally a good bet. In Scotland, sea lochs offer crystal clear water and calm conditions (in Argyll, Loch Goil and Loch Long have good sites) and the Scottish Wildlife Trusts have a series of Snorkel Trails and downloadable leaflet guides to sites and species. The trails are in Arran, Berwickshire, Lochaber, North Harris and North West Highlands.

What do you need? 

Basic snorkelling kit includes a good quality mask and snorkel – flippers are optional. One key decision is the type of snorkel that will best suit your plans. Basic “wet” snorkels have an open top; “semi-dry” snorkels have a splash guard; and “dry” snorkels have a valve that enables you to dive down under the surface without the snorkel and mouthpiece filling up with water. If you expect to do a little more than float on the surface in calm conditions, then a dry snorkel is the best option.

Kit is really down to the person,” says Martin. “I usually use a wet suit, and have fins and a mask and snorkel. A good mask is most important. There are lots of good brands but Cressi make excellent ones.” Key considerations are comfort, durability, and clarity and extent of vision. For this combination of reasons, it’s best to try masks on in person and buy the best you can afford – cheap masks won’t last, and ultimately become plastic waste. Full-face snorkels are also available.

“You don’t have to swim much in snorkelling – it’s really up to you! You can gently move along or more actively swim and dive down. Fins certainly can make a big difference but they’re not essential.”

Grey Sea Slug. Photo: Martin Stevens @sensoryecology
Crystal Jelly. Photo: Martin Stevens @sensoryecology
Beth Pearson