Found thousands of these translucent blue, plastic-looking ovals washed up on the beach today. They have a stiff fin on top and blue jelly underneath. Are they dangerous?

the area with seawater, followed by fresh water, and applying a soothing lotion or cream can help.
If any unusual symptoms occur, such as persistent pain, swelling, or an allergic reaction, it’s advisable to seek medical attention. Such reactions are rare, but it’s always better to err on the side of caution.
6. Why Thousands Wash Up On Beaches At Once 
Mass strandings of Velella velella are not uncommon and are usually the result of wind and ocean currents. These organisms drift on the ocean’s surface, using their sails to