The bluebottles or Portuguese man o' war washed overnight on the tide adding extra colour to the foreshore for morning joggers and walkers.

However, they don't have the same deadly venom as the northern box jellyfish which can kill humans.

No fatalities have ever been reported within Australia or New Zealand from the sting of a blue bottle, according to Australianfauna.com

If you are stung, it is best to wash the area without touching and use a cold pack to relieve the pain and consult a doctor.

Bluebottles range from a blue to a pink hue, with a translucent measuring between 3 to 15 cms. Tentacles can range in length from 15 cms up to 10 metres.

A Warrnambool veterinary said the sting could be potentially threatening to a dog, but he was not aware of any fatalities.

Local resident Louise Watson came across the jellyfish while walking her Italian greyhound Baxter on the beach near the Flume.

"Dog owners should be careful," she said.

"I've seen plenty of these up around Byron Bay and Queensland, but not down here," she said.