There are only a few species of Anaspideans, or sea hares, known from Kwajalein. They mostly live in shallow water, where most species eat algae or cyanobacteria (blue green algae). Some have a thin, entirely or mostly internal shell, and some species are capable of releasing a cloud of purple ink to confuse predators. They are mostly harmless and a few have been used as food by some people, although there are sporadic reports in some areas, such as Western Australia, of dogs being poisoned to death from eating some sea hares washed in on the beach.
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