This is a "bubble print." It shows that a whale is blowing bubbles under the water. These sea mammals do this by exhaling underwater. Try it!
Why do you think whales blow bubbles? "It is hard to say why," says scientist Kim Shelden. "Were they startled by something? Is it a greeting or a warning? Are they just letting us know they are there, or something else entirely? It's fun to think about why these whales blow bubbles. Their environment is nothing like ours, and most of the time we only see the small part that is happening at the surface." More
Photo: Caroline Armon
This picture appears to be a playful bubble ring, likely from a young gray whale. But scientists have written about big cooperative-feeding groups of humpback whales who use their breath to make bubble "nets" to corral small fish into a tight mass. Then the whales swim up through the school of fish with mouths wide open and swallow the "trapped" fish.
Some dolphins also use bubble bursts to herd fish. We have seen young belugas approach our research boats when we are sitting with engines off and the only indication they are near is a bubble ring.