It’s National Marine Week from July 31, and Cumbria Wildlife Trust is urging everyone to grab a bucket and spade and head down to the beach, where you could be in for a surprise.

For most of us, the opening bars of spine-tingling movie Jaws could put you off sharks for life, but in fact the Irish Sea is home to one of worlds biggest.

However, when it comes to a close encounter with the world’s second largest fish – the basking shark, you can feel quite safe in your rubber dingy. That’s because the biggest thing likely to make its way into a basking sharks’ mouth – plankton, is only a few millimetres long.

Well known for their regular appearances around the coast of Cornwall and Scotland’s Hebridean Islands, you may not know that the Irish Sea also plays host to these underwater giants each year.

Boasting a scientific name of ‘maximus’, the basking shark has to be big - up to four tons in fact, more than a brand new Rolls Royce. So how do you get that big by eating only plankton? By having one of the biggest mouths in the ocean and gulping down almost two tons of water per hour, at a very leisurely 3mph. Although a rather more sedate dining style than their predatory cousins, it’s a system that’s kept the basking shark in business since the time of the dinosaurs.

Cheryl Nicholson, marine officer for the North West Wildlife Trusts said: “It’s sometimes hard to imagine that beyond Morecambe Bay or the industrial hubs along the Dee and the Mersey, there are truly amazing marine creatures below the surf.

“Many of us enjoy watching dolphins or seals, but just below the surf there’s one of the biggest fish in the world. We hope that by getting everyone involved in making our giant life-size basking shark sculpture, people will see just how vital it is that we create ‘Living Seas’ for everything that makes a home above and below the waves.”

There are two Marine Week events in Cumbria in August:

Beached Art, St Bees Beach, Sunday 7 August, 11.00am Sand sculpture competition! Just £1 per person. Book your plot online at www.cumbriawildlifetrust.org.uk or telephone 01539 816300.

Shark Event, Biggar Bank, Walney Island , Wednesday 10 August, 11.30am Join the Wildlife Trust to learn about the amazing sharks in the Irish Sea, then make a life size sand sculpture of a basking shark – a massive 12m! We will then go on an eggcase hunt to gather data as part of a national survey which will help conserve sharks, skates and rays for the future.