A LARGE group of moon jellyfish have been spotted in Poole Park Lake this week, creating a mesmerising sight for visitors. 

Resident, Thomas Fishenden, spotted the extraordinary sight on Wednesday evening.

Capturing them on camera, Thomas told the Daily Echo: “I used to work in an aquarium, so I know quite a lot about them.

“They are the most common ones in the UK. Jellyfish are buoyant, so they must have slipped through the gate from the sea and that’s how they’re here.”

Around the size of a plate, moon jellyfish are recognisable by the four circles visible through the translucent white bell.

The four circles are gonads, the reproductive organs located at the bottom of the stomach.

Jellyfish are 95 per cent water and have no brain, blood or heart.

Bournemouth Echo: Moon Jellyfish. Photo by Thomas FishendenMoon Jellyfish. Photo by Thomas Fishenden

The jellyfish can usually be spotted floating just below the surface of the water.

They have short, delicate tentacles that hang down from the sides of the bell and catch their plankton prey using a layer of mucus over their bells before passing the microscopic meals into their mouth parts using special tentacles.

Bournemouth Echo: Moon Jellyfish. Photo by Thomas FishendenMoon Jellyfish. Photo by Thomas Fishenden

Councillor Mark Anderson, portfolio holder for environment and place warned people to leave the jellyfish alone.

He said: “Our conservation officer has found a number of moon jellyfish at the lake at Poole Park.

“The lagoon is emptied and refilled with water from Poole harbour, via the sluice gate, regularly and this is also an opportunity for fish and other species such as jellyfish to move in and out of the lagoon. This helps to support a healthy habitat and is essential in preserving the rare species that thrive in the lagoon.

“It is not unusual for jellyfish to enter the lagoon and as such they should be left alone and should not cause any harm to park users.”