Some species of crabs can do this to improve. Crabs that spend part of their lives in the water, and part out, can blow bubbles. The fluid contains surfactants (a substance composed.
Why Do Crabs Bubble At The Mouth? Shrimp and Snail Breeder
A hermit crab blowing bubbles will appear frothed at the mouth.
Don’t worry about them, they aren’t going to go “mad” and chase you across the beach.
This is a natural process that helps them breathe, especially when they are on land. Crabs that spend part of their lives in the water, and part out, can blow bubbles. Crabs that spend part of their lives in the water, and part out, can blow bubbles. What does it mean when a crab is foaming at the mouth?
Crabs foam at the mouth primarily to expel carbon dioxide from their gills.
