Larval mantis shrimp
When night falls on the open sea, there’s a world to explore as zooplankton swim up from the depths to feed. Many of these small organisms are still larvae, including the mantis shrimp pictured here. Mantis shrimp are voracious predators in their larval and adult phases, and blackwater diving offers a rare glimpse into their early lives. “It’s the nursery of the ocean,” says photographer David Doubilet.
Jellyfish and larval lionfish
Photographers plunge into the deep sea in the middle of the night with bright lights to help spot animals such as this jellyfish (left), moving like a curtain in the breeze, or this larval lionfish (right) surrounded by amphipods, tiny shrimp-like crustaceans.
Doubilet and photographer Jennifer Hayes liken swimming in the night sea to drifting in space. “The only way to know which way is up is to watch which direction the bubbles are going,” Doubilet says.
Some sightings are rarer than others, such as this immortal jellyfish that Hayes photographed in Anilao, Philippines. When threatened, this glowing bell-shaped invertebrate can revert to its earliest life phase—essentially restarting its life. It’s one of several animals considered to be the holy grail for blackwater divers. For Doubilet and Hayes, the elusive blanket octopus tops the list.
Doubilet and Hayes use macro lenses to capture tiny organisms like salps—gelatinous invertebrates that vary from the size of a thumbnail to a hundred feet long. Salps can link up in luminescent chains, using electrical signals to synchronize their movements. “They twist and form these amazing geometric patterns—and then change in front of you,” Hayes says.
Larval carangid and moon jellyfish
To travel safely through the night, some animals form unexpected alliances, like this larval carangid hopping a ride on the back of a moon jelly. Safety is also on the minds of humans, who are at the mercy of the current. Divers drop a rope studded with bright lights into the sea, attached to a buoy at the surface. Both divers and their boat orient toward the light to ensure no one gets lost.
“The underside of the surface of the sea on a calm night is like a mirror,” Hayes says. In this photograph taken by Doubilet, a brilliantly colored flying fish swims beneath the surface of Bermuda’s Sargasso Sea. These fish can glide great distances across the surface by stretching their pectoral fins out like wings.
Sea butterfly and juvenile cowfish
The night sea gives photographers an opportunity to catch an incredible breadth of life. Pictured on the left is a sea butterfly, a free-swimming snail that can be as small as a grain of sand whose foot has evolved into wing-like lobes that flap to propel it through the water. On the right, a juvenile cowfish is drawn to the photographer’s light.
A pelagic squid releases a cloud of ink before vanishing into the depths of Raja Ampat, Indonesia. While mesmerizing, Doubilet says the night sea can be frustrating to photograph because many of the animals are either incredibly small or flee at the sight of a human. “As you move the focus, the creature spins out this way or spins out this way and you might not get it.”
Some animals attempt to camouflage themselves for protection—such as this pipefish, which is pretending to be the stick it’s carrying through the night sea in Anilao, Philippines. Blackwater divers worry about predators, too—especially sharks. But sadly, Doubilet says, sharks have been fished out of most of the places where they dive. “You feel relatively safe for all the wrong reasons.”
Juvenile trevally and jellyfish
This juvenile trevally has hidden itself inside a jellyfish to escape the notice of predators near Moalboal, Philippines. It’s also an effective means of travel. Hayes says she realized while swimming alongside it that the “fish is driving the jellyfish like a motorboat.”
An African pompano, also called a threadfin trevally, swims through the sea, streaming its filaments that resemble the tentacles of a jellyfish. “It’s the equivalent of a marine Sorcerer’s Apprentice,” Doubilet says. "All strange things that are dancing around at night.”
Originally identified as radiolaria—single-celled plankton with a hard mineral shell—this photograph more likely depicts an egg mass spawned by an unidentified species. Many night sea encounters are not immediately identifiable; photographs are circulated within an active community of scientists and divers who work together to learn about this unique ecosystem.
“For photographers all over the world, it is a grandstand seat watching a parade of the most strange and exotic creatures in the world,” Doubilet says. “It is a menagerie that is beyond imagination.”
A male palogic octopus, also known as a paper nautilus, catches a ride from a jellyfish in Anilao, Philippines. “You rarely run into something that doesn’t fascinate you,” Hayes says. “It really is a new macroscopic lens into the sea.”
Amphipod and jellyfish
An amphipod hitchhiker sits atop a jellyfish in the Verde Island Passage, a major shipping lane in the Philippines. Diving in these deep waters surrounded by islands and reef systems offers a glimpse of all types of life. Hayes says that makes blackwater diving irresistible. “The cool thing is we still have these holy grails out there,” Hayes says. “It’s a story that won’t end for us.”