Frosted Nudibranch (Dirona albolineata)

Description: Frosted nudibranchs, also known as alabaster nudibranchs, are translucent white, gray, pink, light purple, or even pale orange. The cerata lining their back are flattened like thin leaves and edged with white lines. They can get quite large, up to 18 cm, but are more often 4-5 cm long when found in the tidepools.

Habitat: They range from Alaska to southern California. They can also be found in Japan and eastern Russia. When looking for frosted nudibranchs, look around rocks or in mud from the low intertidal down to depths of 37 m in the subtidal zone.

Diet: The frosted nudibranch has very powerful jaws to crack open the shells of snails to eat. They also eat sea anemones, hydroids, tunicates, and bryozoans.

Tide Pool Tidbits:

• Frosted nudibranch egg masses contain about 350,000 eggs!

• The flattened cerata on the back of the frosted nudibranch tend to fall of easily.

References: Walla Walla University, The New Beachcomber’s Guide to the Pacific Northwest by J Duane Sept