Portuguese men-of-war sightings on Cornish beaches Published duration 7 September 2012

media caption Dawud Lee, who needed hospital treatment after being stung, said it felt like "a little knife going into my foot"

Portuguese men-of-war have been washed up on beaches in Cornwall according to council officials.

There have been sightings of 13 men-of-war at Portheras Cove in west Cornwall and others at Summerleaze and Widemouth beaches in north Cornwall.

The Marine Conservation Society (MCS) said sightings were on the increase.

The Portuguese man-of-war is not a jellyfish but is closely related, and consists of many tiny marine organisms behaving collectively as one animal.

The man-of-war can cause severe pain, and in rare cases, death.

'Cornish pasty-shaped'

Its normal habitats are the warm seas off Florida Keys, the Gulf of Mexico, Indian Ocean, Caribbean and Pacific.

Dr Peter Richardson, MCS Biodiversity Programme Manager, said: "Between 2003 and 2006 the MCS jellyfish survey received less that 10 reports of Portuguese men-of-war, but since then sightings have increased, to over 60 reports in 2009."

Portuguese men-of-war are about 30cm long and 13cm wide.

The MCS describes the men-of-war as a "Cornish pasty-shaped, transparent purple float with blue, tentacle-like 'fishing polyps' that hang below the float can be tens of meters in length".

Dr Richardson said they "deliver an agonising and potentially lethal sting".

"Because a stranded Portuguese man-of-war looks a bit like a deflating purple balloon with blue ribbons attached, it may attract the curiosity of children."

The sightings come just days after swimmers and surfers were warned that Portuguese men-of-war had been spotted on the Irish coast.