Have you ever seen a giant larvacean, the tiny sea squirt that lives inside a giant mucus house? How about a wildly iridescent bloodybelly comb jelly?
If not, you’re far from alone. In the deepest, darkest parts of the world’s oceans, mysterious and remarkable animals abound. But because of the immense cost and logistical challenges involved in exploring those depths, only a handful of scientists, engineers and well-financed explorers such as James Cameron have been able to see these creatures in the flesh.
However, life in the deep sea may soon be accessible to all. Public aquariums around the world are spending millions of dollars on research and development aimed at putting deep-sea animals on display.
Leading the effort is California’s Monterey Bay Aquarium, which plans to spend $15 million over the next two years to create the world’s first large-scale exhibition of deep-sea life, a 10,400-square-foot display named “Into the Deep: Exploring our Undiscovered Ocean.”
Many of the animals that the aquarium hopes to put on display are found far below the reach of sunlight, in a region called the midnight zone, which extends from a depth of about 3,300 to 13,000 feet.
Much remains to be learned about life at these depths, and no other aquarium has attempted such an exhibit. By bringing these wonders to light, the aquarium hopes to raise public awareness of their existence and their plight, as fishing, warming temperatures and seabed mining threaten to cause permanent damage to ecosystems that, although unseen, underlie those that humans rely on directly.
In recent years, aquariums in Japan and California have successfully exhibited fish and invertebrates from the ocean’s twilight zone, which extends from about 650 to 3,300 feet below the ocean surface. But no aquarium has housed a collection of animals found beneath the twilight zone.
“It’s really hard,” said Luiz Rocha, curator of fishes at the California Academy of Sciences in San Francisco. “Not only are deep-sea fish harder to get, but they’re also harder to keep.”
The Monterey Bay Aquarium and its partner organization, the Monterey Bay Aquarium Research Institute (MBARI), both backed by the Packard Foundation, have two large ships and several remotely operated vehicles at their disposal, some with robotic arms, high-definition cameras, state-of-the-art sensors and a variety of devices designed to suck and grab delicate deep-sea animals from the water.
Many of these organisms possess soft, gelatinous bodies — an adaptation to the physical pressures of the ocean depths, but which at sea level provides all the structural integrity of a wet Kleenex. With the advance of technology, it is finally becoming possible to bring some of these fragile beings to the surface.
Descending into the depths
On a sunny day in mid-February, before the coronavirus pandemic halted operations, scientists from MBARI and aquarists from Monterey Bay headed out aboard the Rachel Carson, a 135-foot-long deep-sea research vessel. They were searching Monterey Bay’s submarine canyon for bottom-dwelling species to scoop up, study and hopefully put on display.
Their task was daunting. The creatures they sought were hidden by darkness in an underwater canyon that, although starting just hundreds of feet from shore, is as deep and steep as the Grand Canyon.
In the ship’s control room, the song “Under Pressure,” by Queen and David Bowie, played as pilots from the research institute directed the Ventana, one of their larger remote-operated vehicles.
“We’re looking for things that are going to look good and are representative of what’s actually down here,” said Paul Clarkson, the aquarium’s director of husbandry operations.
“Here’s a good example,” he soon said, his eyes fixed on a monitor displaying the feed from the Ventana’s camera. The vehicle had encountered a bright orange Brisingid, a type of deep-sea sea star, clinging to a rock on the seafloor. These sea stars have as many as 20 arms, which they can jettison at will to evade predators.
Mr. Clarkson and the other researchers watched as the pilots directed the vehicle’s robotic arm to grab a modified household spatula from an internal compartment and gently wedge it under the sea star.
“Can you come in from there?” said DJ Osborne, one of the Ventana’s pilots, pointing to the right side of the star.
“I don’t know, man, these things are not easy,” replied Scott Hansen, Mr. Osborne’s co-pilot. “They’re stuck like Velcro.”
Several of the sea star’s arms soon popped off. The pilots decided to leave the dismembered organism on the seafloor, where it would have a better chance of survival. A few minutes later the crew found another specimen sitting on a thick layer of detritus. With a few flicks of the wrist, the pilots scooped up the invertebrate and deposited it in a drawer on the vehicle.
After more than five hours in the midnight zone, the vehicle returned to the surface with its drawers and cylinders full of sea stars, nudibranchs, worms and sponges. With the exception of a few sea stars, all the animals collected that day are alive and well at the aquarium.
Over the past two decades, the Monterey Bay Aquarium has attempted to keep dozens of different deep-sea species alive in captivity. Most of the early attempts failed, but each one has revealed something new about the needs of deep-sea species.
Alicia Bitondo, a senior aquarist at the aquarium, is familiar with the challenges of caring for these creatures. Back in February, Ms. Bitondo prepared a meal in a dark, cramped room in the back of the aquarium for one of her favorite organisms, a salmon snailfish named “O.G.”
This bottom-dwelling, deep-sea fish, found off the coast of Japan, looks less like a fish and more like a wad of pink chewing gum that has spent several hours in a hot car. The aquarium acquired O.G. in June 2019 with the goal of figuring out whether the species could be kept alive in captivity.
“When he first came in, he wasn’t eating at all,” Ms. Bitondo said, grabbing a pinch of krill from a plastic cup. “Now I can hand-feed him.”
She deposited a few krill into O.G.’s tank and within seconds the morsels were in the maw of the squishy pink fish.
“You’re such a piggy,” she said, gently tickling the fish’s chin. Salmon snailfish have whisker-like pectoral fins below their mouths that are equipped with taste buds. Tickling these weird whiskers, Ms. Bitondo has found, is a great way to stimulate the fish’s appetite.
Recreating an environment as extreme as the deep sea is an enormous undertaking. The average temperature down there is just 39 degrees Fahrenheit, and the pressure can exceed 5,000 pounds — the approximate weight of a rhino — per square inch. In the early days of deep-sea aquarium design, aquarists believed that deep-sea animals had to be kept in pressurized tanks. However, researchers recently discovered that many deep-sea species can survive at sea level if slowly acclimated.
One of the biggest challenges aquarists now face is getting the temperature, acidity, oxygen and light levels just right.
To keep O.G. and other deep-sea animals healthy, the aquarium developed a seawater system using filtration technology first developed by the pharmaceutical industry. The water pumped into the tanks by the system is bone-chillingly cold and nearly devoid of oxygen, which is exactly how the aquarium’s deep-sea animals like it.
The aquarium made an earlier attempt at putting deep-sea life on display in 1999 with a 7,000-square-foot exhibit called “Mysteries of the Deep.” It featured deep-sea crabs, corals, sharks, sea stars and tunicates from the ocean’s twilight zone. The exhibit was successful, and left many aquarium employees wanting more.
One was Tommy Knowles, a senior aquarist who has been with the aquarium for over 17 years. He was part of the team that figured out how to culture gelatinous comb jellies.
“The best part of my job is working on projects that people said were impossible, and ultimately having success,” he said. “So for instance, the bloodybelly comb jelly. It was considered basically impossible to keep these animals in an aquarium because they are so fragile.”
Now the aquarium can keep them alive for a period thought to be close to their natural life span.
“Anyone who sees this animal is going to be blown away by it,” Mr. Knowles said. The creatures have transparent hairlike cilia that propel them through the water, diffracting light and creating a dazzling display of colors.
“When we first studied it, it was so sensitive to temperature changes that as we photographed it in the lab, the temperature of the water in the containers warmed up by a couple of degrees and then all of a sudden the water was red and the animal was gone,” said George Matsumoto, a senior education and research specialist at MBARI who first described the organism as a separate species. “It’s that delicate. “The fact that the aquarium is keeping them alive is amazing.”
Deep, dark and filled with treasures
For scientists such as Dr. Matsumoto, the breakthroughs in deep-sea animal husbandry made by the aquarium have created opportunities to study deep-sea organisms in greater detail than ever before.
When scientists explore the deep sea with advanced scuba equipment, submarines and remotely operated vehicles, they “only get a glimpse” into the lives of the animals that exist there, Dr. Rocha said.
“We don’t get any information about their behavior, how they mate, what they eat or how they live,” he said. “But when we have them in an aquarium, we can see all of that.”
The role that public aquariums play in society has changed since the first ones were built in the mid-19th century. Those primarily exhibited local fish species and offered visitors information on the best ways to cook and consume them.
Today, aquariums are places where scientists can study marine life up-close, and visitors can learn about their inherent connection to the marine world. “Many people’s first encounter with ocean life is at an aquarium,” said Kevin Connor, the aquarium’s director of communications. It is for this reason that most modern aquariums, especially those accredited by the Association of Zoos and Aquariums, stress the importance of marine conservation to visitors.
“In the last 20 to 30 years, aquariums have become more conservation-minded,” said Samantha Muka, assistant professor of science and technology studies at the Stevens Institute of Technology in Hoboken, N.J.
Dr. Muka, who is working on a book about the history of aquarium technology, said that public aquariums are having a tough time contributing to the conservation of deep-sea creatures because they are incredibly difficult to study and showcase to the public.
“There is a big difference between seeing something on-screen and seeing something in an aquarium,” for scientists and aquarium visitors alike, Dr. Muka said.
As technology has progressed, aquarium buffs like Dr. Muka have anxiously awaited the arrival of an exhibit like the one the Monterey Bay Aquarium is attempting to curate.
“We know large steps forward like this do make a big difference in how excited people get about going to aquariums,” she said. “The more we can do with tanks, the more we can teach people about the marine world. We can show them it’s more than just a resource to be mined.”
In creating the world’s first large-scale exhibition of life in the deep sea, the Monterey Bay Aquarium hopes to do just that.
“The deep sea is so important,” said Kyle Van Houtan, the aquarium’s chief scientist. “It’s the largest living space on our planet, but people don’t really have access to it, so it’s up to us to bring it to them.”
The aquarium’s forthcoming exhibit will take visitors on a tour of the midnight zone, starting in the mid-water with bioluminescent jellyfish and cephalopods, and ending on the seafloor with whale bones crawling with Japanese spider crabs and other seafloor scavengers.
Although scientists have only begun to scratch the surface when it comes understanding of life down there, it is clear that human activities are having catastrophic and long-lasting impacts on deep-sea ecosystems around the world.
“The deep is the engine that drives life in our oceans,” Dr. Van Houtan said. “It’s the beating heart of our climate system. But we are exploiting the deep in ways we never have before, so I think it’s time to talk about this and to tell everyone about the importance of the deep.”
Fishing trawlers drag nets across the seafloor, destroying deep-sea coral reefs that took tens of thousands of years to form. Miners bore into the seabed in search of copper, nickel, aluminum, lithium and cobalt, stirring up sediment and exposing deep-dwelling species to noise and, often, chemical pollution.
Dr. Van Houtan hopes that when visitors will discover that the ocean’s midnight zone is a part of our planet that is as worthy of protection as any other.
“If people come away from this exhibit thinking that they’ve just seen an “other” place than I think we haven’t done our job,” he said. “Our job is to get them to see themselves in this place and not to see it as a different planet.”