WILD LIFE | 01.24.17

Star Attraction

Even a night sky of pirouetting stars can’t upstage the otherworldly beauty of a red-gilled nudibranch.

Photograph by Alexander Mustard

SHARE

As it cruises along a kelp frond, a red-gilled nudibranch (

Flabellina pellucida

) seems to emerge straight out of its cosmic backdrop. But this sea slug is very much ocean-bound, navigating waters just off the Norwegian coast near Gulen with the help of a pair of frosted antenna-like appendages, called rhinophores, that detect chemical signals from the surrounding environment.

Nudibranch means “naked gills,” a reference to the collection of swaying appendages this species—one of some 3,000 sea slug varieties—carries on its back. But these brilliant raspberry hues, beautiful as they are, aren’t meant to attract. Rather, the vibrant color serves to warn predators of chemical defenses stored inside the nudibranch’s tissues. In a stunning biological feat, red-gilled nudibranchs are able to ingest the stinging cells of their prey—tiny jellyfish-like invertebrates known as hydroids—and then transfer the cells to their gill tips for use in their own defense. Scientists think further study of this unique chemical arsenal could lead to advances in pharmaceuticals to treat everything from cancer to HIV infection.

Photographer Alex Mustard created this otherworldly scene with no fewer than 77 separate photographs merged into a single image. One photo captured the nudibranch slinking along the edge of a kelp frond, while dozens more captured Norway’s night sky. With his camera pointed toward the North Star, Mustard took a series of long exposures, resulting in star trails that trace the rotation of the Earth.

Gulen, Norway

SHARE

ABOUT THE Photographer

Dr. Alex Mustard has been taking underwater photographs for more than 30 years and has worked as a full-time underwater photographer for the past 12. His work has been displayed in exhibitions around the world and has won numerous awards, including seven wins in the BBC Wildlife Photographer of the Year competition and four category wins in the British Wildlife Photography Awards. His 2007 book “Reefs Revealed,” won the International Grand Prize for the best book of underwater photographs.

Alexander Mustard

RELATED

TOPICS

ARTICLES

From the beautiful to the bizarre, this photographic showcase of life on Earth shines a light on some of our planet's most amazing species and places.

photo gallery | 05.01.18

The Big Picture 2018

Perched atop the elegant back of a Spanish dancer nudibranch, this tiny shrimp enjoys one of the safest seats in the sea.

spotlight | 08.30.16

The Emperor's Throne

From the beautiful to the bizarre, this photographic showcase of life on Earth shines a light on some of our planet's most amazing species and places.

photo gallery | 04.30.19

The Big Picture 2019

bioGraphic

is powered by the California Academy of Sciences, a renowned scientific and educational institution dedicated to exploring, explaining, and sustaining life on Earth.

©2018 California Academy of Sciences. All rights reserved.