marine slug

The circle of life: Fairly common in Monterey Bay National Marine Sanctuary, this sea slug, Navanax inermis, is a colorful predator of nudibranchs like Hermissenda opalescens here. 

In this photo, you can see Navanax’s mouth preparing for the hunt – and the nudibranch will be gone in the blink of an eye. 

(Photo: Steve Lonhart/NOAA)

The Alabaster Nudibranch can be found in the temperate waters of the Pacific, from Alaska to California and along the coasts of Russia and Japan. The beautiful, wispy white tipped cerata are actually the animal’s lungs. But don’t let it’s delicate form fool you, this nudi’s jaws are strong enough to crack open the shell of a snail, one of its preferred meals - photo taken at Seattle, Washington

Two small orange-spike polycera (Polycera atra) inch gracefully though their home in Channel Islands National Marine Sanctuary. 

These nudibranchs have bright orange tips on their gills, from which they get their common name. 

(Photo: Evan Barba)