How long do jellies live?
In the wild, jellyfish medusas typically live only for about one season, around 5-8 months. That’s just long enough to eat a lot, grow big and reproduce. New medusas typically appear the next year to start the cycle all over again. At the Tennessee Aquarium, some of the large jellies like the moon jellyfish and the sea nettles can live up to 2 years. Some of the smaller species, like umbrella jellyfish and blubber jellyfish, have a shorter life expectancy of only 6-8 months.