The jellyfish for which Chesapeake Bay is widely known in the summer is the Sea Nettle (Chrysaora quinquecirrha). It occurs from Cape Cod south along the U.S. East Coast, Caribbean and Gulf of Mexico, yet it abounds in Chesapeake Bay in numbers unequaled elsewhere. It occurs most abundantly in the tributaries of the middle Bay (salinities 10 - 20 ppt), where it is white in color.

In the southern Bay, it often has red/maroon markings on the long central tentacles and on the swimming bell.

The Moon Jelly (Aurelia aurita) is a clear, flattened disk, with numerous small tentacles around the edge, and a pink four-leaf clover design in the middle.

The Lion's Mane jellyfish (Cyanea capillata), common during the winter, is brown in color and has long tentacles hanging from the edge of its swimming disk and middle.

Non-stinging ctenophores or comb jellies are extremely abundant during the summer. They are very transparent and are seldom noticed, except at night when they glow if disturbed.

In the autumn, the Mushroom Cap jellyfish (Rhopilema verrilli) may enter the Bay. It has a deep swimming bell without tentacles, and is creamy white with darker markings on the sturdy central tentacle structures.

The Cabbage Head or Cannonball jellyfish (Stomolophus meleagris) is like a white softball, or larger, and has a short, hard tentacle structure in the middle.

Adapted from Jellyfish in Chesapeake Bay and Nearby Waters by Dr. Jennifer E. Purcell, UMD/HPL: P.O. Box 775, Cambridge, MD 21613

Ctenophores image courtesy of and used with permission from UnderWater World - Sunshine Coast