Cannonball jellyfish can't swim. Instead, they go where the winds and currents take them. A strong easterly wind on Friday pushed the jellyfish onshore, not only on Tybee, but other Georgia beaches as well, said Tyler Jones, a spokesman for the Georgia Department of Natural Resources. "It's just a regular occurrence," Jones said. "It isn't like a sign of the apocalypse or anything." Cannonballs are the most prominent species of jellyfish in the Southeast, according to Georgia's DNR website. During the summer and fall, they make up over 16% of biomass on the coastline. "They primarily eat zooplankton and red drum larvae," the website says. "When disturbed or threatened, the cannonball jellyfish will secrete a toxic mucus that will harm small fish, and drive away most predators."