Sea hare

Animal Facts

  • Scientific Name

    Aplysia californica

  • Animal Type


  • Diet

    algae and eelgrass

  • Size

    up to 16 inches (40.6 cm), 30 pounds (13.6 kg)

  • Relatives

    sea slugs and marine snails; phylum Mollusca, class Gastropoda

Natural History

Each sea hare is both male and female and has both sexual organs. Sea hares may lay up to eighty million eggs apiece but most of these are eaten by predators.


Many kinds of plants, birds, fish, shellfish and other animals depend on the special mix of fresh and salt water found in sloughs and estuaries. When we protect wetlands against development, we protect the homes of many animals.

Cool Facts

When threatened by predators, sea hares release a dark purple fluid in defense. The ink gets its purple color from a pigment in the red algae that makes up part of the sea hare's diet. 

Sea hares can't see like we do; their simple eyes can only tell light from dark.

 Animal Guide Home