Have you any idea why lady bird beetles would congregate on seaweed at the beach? This is Point Reyes National Seashore, Marin County, north of San Francisco. Certainly no aphids on seaweed! Do they eat something else? Also, do these beetles get their spots in stages and are these all convergent ladybugs even though they don’t all have the regular spot pattern?
Ladybird Beetles are often swept out to sea or out onto large lakes due to wind patterns. They climb aboard whatever “raft” happens to float by, like seaweed. When the seaweed washes ashore, the Ladybird Beetles reach dry land and eventually fly away. There is much individual variation in coloration within species.