Jellyfish underwater ocean. Located all over the world in deep shallow cold and warm waters alike jellyfish are easily one of the most recognizable sea creatures that stingaccording to the mayo clinic victims of this tentacled creature experience things like prickling pain red tracks on the skin in a tentacle like pattern and itching and swelling at the site of the sting. A giant barrel jellyfish has been spotted off the coast of cornwall by divers. The mystical creatures that live in the ocean will forever win over our halloween hearts. Air pollution is also a contributing factor by carrying off pesticides or dirt into the ocean.