By John Balson @JJBalson

A GIANT manta ray gave a British diver a show of thanks - after he untangled it from a commercial fishing line

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Videographer / Director: Paul Slater & Don Shellhammer
Producer: John Balson, Nick Johnson
Editor: Joshua Douglas

Caught in a trap: A manta ray swims away from divers who are trying to cut it loose from a fishing line

Diving instructor Paul Slater, 54, was on a group trip off the coast of Costa Rica when they spotted the 16ft giant caught up in a net.

Wing damage: The fishing line had caused injuries to the manta's body as it tried to escape

With help from American Don Shellhammer and their dive master, they swam up behind and used knives to unpin it from the line.

Freedom: The 16ft manta ray swims into the distance after being rescued

Although it was scared at first and swam away they said it eventually slowed to a stop so they could release it.

They then watched in amazement as it finally broke loose and began to swim around them in barrel rolls in what looked like a gesture of thanks.

Remote: The rescue unfolded on May 17 off Cocos Island, about 550km off the Pacific Coast of Costa Rica

Paul, who is originally from Leeds but now lives in New Orleans, said: "It was a wonderful heartwarming event that we all cherished in being able to be involved in. I sincerely believe the display was a thank-you to us."

Dragged back: The ray was snagged in up to 200ft of line causing deep injuries to its back and side

The rescue unfolded on May 17 off Cocos Island, about 550km off the Pacific Coast of Costa Rica.

The remote island is a protected marine sanctuary and popular among divers searching for encounters with rays, sharks and dolphins.

With help from American Don Shellhammer and their dive master, they swam up behind and used knives to unpin it from the line

It is believed to have been the inspiration for the fictional setting of Jurassic Park - although no filming ever took place there.

Spooked: The manta ray initially swam away from the divers but then slowed down to a halt

Recalling the manta ray rescue, Paul said: "I saw a giant manta ray swimming above me.

Ray of hope: Paul Slater, 54, begins to cut the manta ray loose from the fishing line

"I approached the animal and immediately noticed it was snared in a commercial fishing line around its body and dragging at least 200ft more behind it.

Manta Force: The dive team catches up with the 16ft ray in the Pacific Ocean

"I was shooting GoPro video at the time and the dive master and I approached the animal from behind, deciding originally to cut the trailing line some 20ft behind the animal.

Fish knife: One of the divers begins to remove the net from the manta ray

"We made a first cut of the line around the body, but he was pretty spooked and swam off.

Celebration: After being released the manta ray was said to have performed barrel rolls of thanks for the divers

"I believe he then realised we were there to help and it circled back around, we came back to him and proceeded to cut the remaining line from him and free him.

"The manta stopped swimming completely so we could work on him. It clearly knew we were trying to help it.

The rescue took place on May 17 during a diving trip off Cocos Island, Costa Rica

"After it was released the manta then proceeded to stick around and do barrel roles for lots of photo ops - which we are convinced was in appreciation of our efforts."

Sadly marine life isn’t always safe from man’s interference.

Rescuer: Paul Slater, 54, filmed himself and others cutting the manta ray free

Although the area is a protected national park there is an ongoing battle with illegal fishing vessels looking to capitalise on the abundant marine life with the 12 mile exclusion area of the island.

Park rangers have found themselves battling to remove baited fishing lines up to two miles long, which often result in non-commercially valuable species being caught and killed.