About the Strawberry Squid
For creatures of the ocean twilight zone, the ability to light up (also called “bioluminescence”) is essential for communication—but it also makes some animals vulnerable to being spotted by larger predators. This cost-benefit is on spectacular display in the strawberry (or jewel) squid, named for strawberry-colored cells called photophores that dot its skin and provide its distinctive glow.
Like others in its family, strawberry squid have asymmetrical eyes that let it perceive light in both dim and bright surroundings. A large, tubular, yellowish eye angles towards the surface, letting the squid spy the “silhouette” of its prey against the dimly lit water from above. A smaller blue eye, measuring about half the size of the yellow one, looks downward for glimmers of light: the telltale signs of bioluminescent animals that could be its next snack. Another adaptation—its semi-upright posture—lets the strawberry squid simultaneously look up, down, and sideways as it jets through the ocean.
Strawberry squid can be found in the tropical and subtropical waters of the Atlantic Ocean at depths ranging from 1,000 meters (3,300 feet) to the surface, where they come to feed at night.
|Common Name||Strawberry Squid|
|Scientific Name||Histioteuthis heteropsis|
|Other Names||Cock-eyed squid, jewel squid|
|Size||Female mantle length is about 20 cm (8 inches); males are slightly bigger|
|Discovery||S. Stillman Berry, 1913|
|Eats what?||Unknown, but likely a mix of small crustaceans and fish|
|Eats how?||One specialized eye looks for food silhouetted above it, while the other scans the darker depths for bioluminescent creatures|
|Is eaten by?||sperm whales, Risso’s dolphins, seabirds, sharks, tunas and lancetfish|
|Bioluminescence||Yes, on the sides|