California sea slug (Aplysia californica)

The California sea slug (Aplysia californica) is a gastropod mollusk of the family Aplysiidae. It and all species of this genus are commonly referred to as sea hares.

It is found in shallow areas associated with algae such as Gracilaria, Ulva,
Enteromorpha and seagrasses of the genus Zostera.

Aplysia is a macrophage with high growth rates and a voracious appetite,
ingesting up to 100 g of fresh algae per day. It prefers green algae,
red and coralline algae.