Underwater worlds | In conversation with Katie Maggs

Presented by Orca.


Meet Katie, a fully qualified snorkel instructor and the ultimate underwater enthusiast behind @‌tonicofthesea. She’s all about unveiling the hidden wonders of our coastline, showcasing the utterly mesmerising marine life that calls it home. But that’s not all. Katie’s on a mission to protect our oceans through local seagrass initiatives and a range of exciting conservation projects. We recently joined forces with Orca to catch up with Katie and discover the amazing work she’s doing. 

^ Katie wears the Orca Vitalis Thermal Open Water Swim Wetsuit

Katie Maggs

My name is Katie Maggs (@tonicofthesea) and I am a fully qualified British Sub Aqua Club (BSAC) snorkel instructor and registered snorkel centre in Penzance, Cornwall.

I learnt the basics of sea swimming and snorkelling as a child with my father in local Cornish coves and later developed a passion for the conservation of marine life and subsequent interest in marine wildlife photography.

I also work as a marine mammal medic for the BDMLR (British Divers Marine Life Rescue) - carrying out seal, dolphin, porpoise and whale rescues throughout the year and I am a committee member for the Mounts Bay Marine Group whose aim is to conserve and protect our local marine environment.

As an experienced snorkel instructor and underwater photographer, I am an ambassador for conservation along our Cornish coastline. With the team at Mounts Bay Marine Group, I am currently working on local seagrass bed and kelp forest monitoring, cuttlefish conservation hatching projects and baby lobster release activities with the National Lobster Hatchery.

I also have a BAFTA nominated award winning short film 'Tonic of the Sea' made about my journey. The film highlights recovery from chronic stress, anxiety, and burnout through daily outdoor swimming in the sea. It has been shown around the world and is currently being used in clinical practice to support individuals suffering from physical, emotional, and psychological symptoms linked to stress, anxiety, exhaustion, and depression.

^ A selection of images taken by Katie whilst out exploring.

As a BSAC snorkel instructor I snorkel all year round along the Cornish Coastline at low tide to photograph the array of fascinating marine life found here. I offer low tide snorkel experiences for all ages and abilities, and I also offer social prescribing for snorkelling for the NHS, Women’s Aid and for Age UK.

When I take people snorkelling in Cornwall their reactions are often emotional and incredible -I get a lot of shock and a lot of joy at how totally magical it looks under there. People say, ‘How is this in Cornwall - This is ridiculous!’. At points I couldn’t stop myself from smiling and laughing, because people would put their faces in and pop right back up saying ‘WOW’, ‘WHAT? THIS IS SO AMAZING!!!!’.

It truly is like an underwater garden under there in the summer months when the conditions are calm and fair. I spent spring and summer watching complete happiness and joy wash over people’s faces. So many people book for fun in their holidays with friends and family, some book that are local and want to come and learn more about their local marine life.

I keep a journal of snorkelling throughout the seasons. The flora and fauna changes so much! You get such an array of amazing marine species. It’s not just the plants that change on land, it’s under the ocean too. The colours from spring to winter. The seaweeds, they change dramatically. Spring and summer are illuminous pinks, yellow candyfloss, blues, and vivid greens. It almost looks fake. In autumn and winter, you get mauves, burgundies, and chestnut colours. The species change – there are lot more cuttlefish in the summer and different varieties of jellyfish that the changing currents bring in.

I also saw a sea spider for the first-time last year. I didn’t even know they existed! I mean a swimming spider must be up there with one of the weirdest things I’ve seen in my life! I’ve also watched cuttlefish squirting ink and changing colour right in front of me! It’s just incredible - I’m always learning still myself and completing research about all the incredible marine creatures that I see!

You can also often get approached by seals, they’re like inquisitive puppies of the sea, but sadly they don’t realise that they are affecting their own feeding and rest cycles by trying to interact with humans. Where possible we should never attempt to interact or approach seals because we are interfering with their main job of hunting, feeding, or resting. I did have an amazing encounter once with a 250kg male seal, who was longer than me! He swam right underneath me so at one point my chin was resting on his head! He was just looking at me with these huge beautiful big black eyes. I could feel his breath and whiskers brush on my hand while I held my Go Pro, it was a truly remarkable experience.

You know they’re wild animals, they have very sharp teeth and are incredibly strong, an encounter like that with a wild animal makes you feel very insignificant, humbled, and small! 

I always feel you are never more connected with nature than when you are at the mercy of the sea, and I really enjoy sharing my love for the ocean with other people through my snorkel experiences under the sea! 



1. The Orca Thermal Neoprene Swim Cap
2. The Orca Vitalis Thermal Open Water Swim Wetsuit
3. The Orca Open Water Safety Buoy / Tow Float

Updated on 27th October 2023

Originally published on 20th October 2023 in Diving

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