Flower Hat Jelly

Lifestyle

Jellies are the simplest multi-celled animals that have muscles and nerves for movement. Though they have no head, heart, brain, bones, or eyes, they are powerful ocean predators. The stinging cells of the flower hat jelly’s tentacled fringe cause pain, but not death. They can quickly coil and uncoil these tentacles when needed, to capture food, defend themselves against predators, and keep competitors at a distance. The flower hat jelly spends some time on the ocean floor, and some time swimming closer to the surface. Much about its lifestyle remains a mystery.

Food

Flower hat jellies eat mostly small fishes and some marine invertebrates. It captures its prey by injecting venom from stinging cells in its tentacles. Like all jellyfish, it can grow or shrink depending on its food supply. When food is scarce, it can shrink in size so it needs to eat less. It grows back up to its full size when food is plentiful.

Some of My Neighbors

Anchovies, shrimp, grouper, snapper, soft corals

Life Cycle

A jelly’s life cycle consists of various stages. The adult form of the jellyfish, called the “medusa,” reproduces sexually and swims freely. Its offspring is called a “polyp” and looks like a small, round stalk. The polyp anchors itself to the sea bottom, then divide and grow into baby jellies called “ephyra.” Flower hat jellies reproduce in “blooms,” reproductive event that spawn dozens of identical jellies. It’s thought that jelly blooms occur when waters are overfished, and natural predators are no longer present to keep the jellies’ populations in check.

Population Status & Threats

Flower hat jellies are rare, but their status is not known. In general, jellyfish are an important indicator species for the health of the ocean. When they occur in great colonies, or blooms, it can signify increasing pollution, and an ecosystem that is out of balance.

WCS Conservation Efforts

Jellies and other cnidarians inhabit fragile, intricate marine ecosystems that are highly prone to climate change and other threats. WCS conducts coral reef conservation projects on East Africa’s Indian Ocean coast, and in Madagascar, Belize, Nicaragua, Indonesia, Papua New Guinea, and Fiji.