The Cruelty of Sensory Deprivation

Sometimes when Rocky, Rambo, and Johnny are chasing live fish in the foraging pen, we observe them underwater to determine how many fish they catch. It is such a far cry from what they experienced when they were confined in a concrete swimming pool — begging for dead fish as food rewards for good behavior, like dolphins in dolphinariums do every day. We can hear them using their echolocation during the hunt, and we see them chasing the fish at great speed.
Echolocation is one of nature’s most fascinating and complex inventions. It enables dolphins to explore their surroundings 3-dimensionally by interpreting the echoes of sound waves that bounce off of objects in the water. A dolphin does this by producing high-frequency clicks from its nasal passages. The clicks are passed through the dolphin’s melon (forehead). The melon is filled with fatty fluid and acts as a sound lens. After passing through the melon, the sound waves travel into the water and bounce off of the object the dolphin wants to investigate. The sound waves travel back to the dolphin and are received by the dolphin’s lower jaw, which is also filled with fatty fluid. From the jaw, the sound waves are delivered to the dolphin’s brain via its inner ear, and the dolphin now interprets the acoustic information and translates it into a detailed image.

After the show had ended, this dolphin just lay on the surface of water of its holding tank at the Attica Zoo in Greece, with nothing to explore and nowhere to swim to.

Miami Seaquarium’s steel training tank was used for some of the five dolphins who played the role of “Flipper.”
Rocky, Rambo, and Johnny’s continuous clicks remind me of a conversation I had years ago with a dolphin trainer named Sabrina. At the time, she worked at a Danish facility that keeps wild-caught harbor porpoises in captivity, but she told me she once worked at the dolphinarium in Harderwijk, Holland. Dolphin Project has participated in several protests in front of Harderwijk dolphinarium. Prior to one, I entered the dolphinarium with Femke den Hass, who is Dolphin Project’s Indonesian campaign manager. We wanted to observe and document the dolphins’ living conditions. Following their trainers’ commands, the dolphins obediently went through their repertoire of trained behaviors, such as tail walking, “singing,” and beaching themselves onto the concrete platform. When the show was over, the dolphins returned to their barren, lifeless tanks and just lay there in their dreary prisons with nothing to do and nowhere to swim to. It was heart-rending to see them entombed in the stagnant water, surrounded by walls to all sides and not enough space to swim normally. Their lives were at a complete standstill, and they could swim only a few feet before hitting a wall.
Hundreds of dolphins are stuck inside concrete show stadiums all over the world. I often wonder what it is like for these complex sonic beings to find themselves incarcerated in minuscule tanks where their natural abilities can find no expression. They can’t employ their awe-inspiring echolocation for any of the things they would in nature. They can’t use it to catch live fish since trainers provide dead fish as food rewards during shows, swim programs, and training sessions. They can’t use it to explore their underwater world because there isn’t anything to investigate in a barren, lifeless tank. They certainly can’t use it to navigate because they aren’t going anywhere. Their echolocation is wasted, and it is inconceivable to me that some people still think restraining these brilliant minds in such a bleak, empty world is justifiable. The sensory deprivation humans subject them to is simply cruel.
I asked Sabrina how she felt about it. “Isn’t there even a small part of you that thinks it’s wrong to confine these sonic creatures inside concrete tanks?” Without a moment’s hesitation, she responded, “No, not at all. It doesn’t matter if dolphins in a tank can’t use their sonar because in a tank they don’t need it.” She was smiling as she said it, as if it made perfect sense. But it didn’t, at least not to me. I think it’s much like locking up a human being in a dark room, feeding him three times a day, and saying it doesn’t matter he can’t use his vision because his physical needs are being met, and he does not need his vision for anything. But just because his captors keep that human being alive doesn’t mean he does not miss his freedom and being able to use his eyesight.
I am convinced the same is true for dolphins. Living in accordance with their true nature and putting all their natural abilities to use fills their lives with purpose, vitality, and quality. Using echolocation undoubtedly means a lot more to dolphins than we can even imagine from our limited point of view, and brushing that ability aside as irrelevant by saying that captive dolphins don’t “need” it constitutes a self-serving combination of human arrogance and superiority. It’s the same as saying that nature really has no clue what it’s doing, and millions of years of evolution is not worth paying attention to.

The albino dolphin known as Angel is trapped inside a glass and concrete tunnel at the Taiji Whale Museum in Japan. According to the dolphin captivity industry, a barren tank such as this one is a perfectly suitable habitat for dolphins.

Dewa (left) and Johnny languished for more than a decade in this shallow swimming pool at the Melka Excelsior Hotel in North Bali, Indonesia. Credit: DolphinProject.com
Rambo, Rocky, Johnny, and all the other dolphins that ended up at the Melka Excelsior Hotel in Lovina, North Bali, were confined in shallow swimming pools. In between shows and swim-with-the-dolphins sessions, they could be seen swimming in small circles or staring at a concrete wall. In 2019, Lincoln O’Barry, Femke den Haas, and our Indonesian dolphin rescue team determined that Dewa, Johnny, Rambo, and Rocky, all captured from the wild, were no longer using their echolocation except when their trainers told them to. “The dolphins that were used in the hotel’s so-called dolphin-assisted-therapy program were trained to send out a series of clicks on command,” says Femke. Now-deceased Dewa was frequently exploited in the hotel’s dubious dolphin therapy package, which catered mainly to Russian families with autistic children. The hotel’s healing scheme was based on the idea that a dolphin’s echolocation can somehow heal humans from all sorts of illnesses, and an ad posted online at the time promised relief from autism, back pain, and other ailments. But dolphins cannot heal people, and even if they could, it would never justify destroying their lives by capturing and confining them. Captive dolphins can’t even heal themselves, and the dolphins at the Melka Hotel undoubtedly suffered every day as a result of their capture and confinement. I feel sure that Rocky, Rambo, and Johnny still remember their violent capture in the Java Sea years ago, and I also think they remember the 30-hour truck ride to the Melka Hotel. Those years of giving rides to people and performing in theatrical shows will always be a part of their life experience, and we can’t change that. But we can let nature take over as much as possible, and at the Umah Lumba Rehabilitation, Release, and Retirement Center in Banyuwedang Bay, West Bali, they can finally once again use their echolocation to catch live prey.

Rocky, Rambo and Johnny heal and thrive at the Umah Lumba Rehabilitation, Release and Retirement Center in West Bali, Indonesia. Credit: DolphinProject.com
Femke and our Indonesian team of dolphin caregivers have been giving the dolphins live fish since May 2020. “We have a great collaboration with the locals in the area who are familiar with our dolphin rescue project. Before we even built the sea pen, we introduced ourselves to the local community and let them know that we would like to work with local fishermen to obtain live fish for the dolphins,” says Femke. Because of the interest and commitment of the area’s fishermen, we are able to introduce many different kinds of live fish to the dolphins’ foraging pen. Hearing Rocky, Rambo, and Johnny use their echolocation to catch the fish is amazing, and I wish the dolphin trainer I spoke to years ago could experience it, too. Perhaps then she would change her mind. Perhaps she would realize that employing their awe-inspiring skill of echolocation to identify prey, navigate, travel, and explore their environment is what nature intended for dolphins to do, and that we have no right to take that away from them. It is not up to humans to determine what a dolphin’s needs are. It is up to nature, and nature has made it quite clear that dolphins belong in the oceans where their highly evolved ability to “see” with sound serves a purpose.
Watch: Rocky, Rambo and Johnny in the foraging pen at the Umah Lumba Center, Bali, Indonesia
Featured image: Beachie hovering near the bottom of his tank, Dolfinarium Harderwijk. Credit: Yvon Godefroid