Jellyfish (also called Sea Nettles) are in the Chesapeake Bay, but not everywhere. The beautiful, but dangerous, creatures are found mainly the middle and lower sections of the Bay, where the water is saltiest.
When they show up varies from year to year.
What are Jellies/Sea Nettles?
Jellyfish are typically, but not always, clear and that makes them difficult to see. They have long tentacles dangling as they pulsate through the murky Bay water.
You know when you come across one. First you’ll notice the tentacles; they feel like hair floating through the water. Then you feel the sting that doesn’t go away any time soon.
Once they arrive, they’re going to hang around until about October.
Type of Sea Nettles in the Chesapeake Bay
In the Chesapeake Bay, you’ll most likely come across moon jellyfish — peaceful, pretty, blobby things floating around.
Moon jellies sting, but it’s a small hurt.
Salps don’t sting.
Man of War nettles are big and pack a painful brush as they go by. They tend to stay closer the ocean.
How to Avoid Jellyfish
The government tries to figure out where they are and provides some prediction.
NOAA, National Oceanic and Atmospheric Administration, actually has a sea nettle prediction website, but it’s often out-of-service.
A reliable source is found in the data being filed from the area bouys (below). This is a dense website, but you’ll find Sea Nettle Probability under “Water Quality.”
The key to avoiding jellyfish is to find fresh water.
Where to Swim When Jellyfish Arrive
There are several Chesapeake Bay beaches that are just out of jellyfish range. The northern part of the Bay is pretty good year-round.
Privately-owned beaches in the briny Bay areas often surround the swimming area with nets protecting swimmers from stings.
Here are some mid to upper Chesapeake Bay beaches that are less briny or are surrounded by nets.
What to Do When Stung by Jellyfish
If you get stung by a jellyfish, ChesapeakeBay.com suggests liberally sprinkling a meat tenderizer or baking soda on the hurting area depending on what kind of jellyfish you came across. If that doesn’t work, it might have been a PhYsalia (a man-of-war). Try vinegar.
The only way to avoid getting stung in jellyfish-infested waters, according to the Chesapeake Bay Program, is by wearing a wetsuit — or pantyhose.