Man O' War

Intrepid swimmers in Ulster beware! I have read that the Portugese Man O' War was been spotted in waters off the Irish Republic.

I swam at Portballintrae, County Antrim, a few weeks ago.

The men-of-war, which look like jellyfish, can cause severe pain and in rare cases,can be fatal.

There is a risk that they may drift into Northern Ireland.

Portuguese men of war are about 30cm long and 13cm wide and it has tentacles that can reach 50m in length.

It is not a true jellyfish, but a floating colony of closely-related hydrozoans that normally live at the surface of the open ocean.

The colony floats from the bottom of an air-filled float, and has many long thin tentacles hanging below that it uses to catch fish.

A sting may lead to an allergic reaction. There can also be serious effects, including fever, shock, and interference with heart and lung function. Stings may also cause death, although this is extremely rare.