Mysterious jellyfish-like creatures wash up on California beaches.

By-the-wind sailors, blue jellyfish-like creatures, are washing up on California beaches from Dana Point to Point Reyes National Seashore. The hydrozoa, known by the scientific name Velella velella, are not dangerous to humans but can sting. They are part of the Cnidaria group, which includes jellyfish and corals. Their presence may be a sign of El Niño events, which warm the ocean water in the Pacific Ocean and result in a change in weather patterns across the globe. Climate change may also make massive blooms of by-the-wind sailors more common.