Beijing, March 28 (Youth.cn) - On March 27th, 2024 local time, a beach in Marin County, Northern California, was spotted with an abundance of marine creatures featuring transparent "triangular sails". Recently, several beaches along the U.S. West Coast have been "occupied" by them. These creatures often drift on the sea surface in large groups, moving with the sea breeze and ocean currents, hence they are known as "by-the-wind-sailors", also referred to as Velella. Photo/ VCG