If you are on Bettystown Beach over the next few weeks watch out for the lion’s mane jelly

They have a nasty sting and can grow up to one metre in diameter and are translucent brown to reddish in colour.

One jellyfish can have nearly a thousand tentacles that can be each three to four metres long.

The sting of the lion’s mane can be very painful to humans and can cause severe allergic reactions in some people.

Dog walkers should be wary and ensure their animals keep their distance as their pets can become sick if they come into contact with the jellyfish.