This stinging nettle is common on the East Coast from mid-summer through fall. Mildly toxic, it is often seen as a nuisance on beaches because it can deliver a painful sting. The East Coast sea nettles are smaller than their West Coast counterparts, reaching approximately four-feet in tentacle length and about six inches in bell diameter. They are opaque, and like all jellies, are plankton eaters. The moon jelly can reach 16 inches in diameter, and it has four fringed oral arms underneath for food.
Moon jellies feed on plankton.
It uses its invisibility to conceal itself from predators when there is no place to hide. These jellies have about 200 short tentacles and feed on invertebrates and larvae. Umbrella jellies are known as hydrozoans, which means that their offspring live in colonies as polyps and then bud into small adult-like animals before maturing. Hydrozoans also tend to be smaller than other species of jellies. They prefer cool water temperatures and dwell in the North Pacific coast from Santa Barbara, CA to Alaska and the Bering Sea.