Photograph by Jean Chung, National Geographic
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In a holding tank at the Seoul Zoo, Taesan (foreground) and Boksoon learn to eat live fish again. They're scheduled to be released off Jeju Island in June.

Photograph by Jean Chung, National Geographic

Theme Park Dolphins May Be Set Free—Are They the Last?

Two captive Indo-Pacific bottlenose dolphins, called Taesan and Boksoon, are on track to be released into the wild—the latest in a string of theme park dolphins that have been set free in recent years.

Two captive Indo-Pacific bottlenose dolphins, called Taesan and Boksoon, are on track to be released into the wild, the Korean Animal Welfare Association announced this week. They are the latest in a string of theme park dolphins that have been recently set free.

The marine mammals are currently swimming in a sea-pen off the South Korean island of Jeju (map), as a prelude to being returned to the open ocean. (Read in the latest issue of National Geographic magazine: "Can Captive Dolphins Return to the Wild?")

They were transported there from the Seoul Grand Zoo late last week, and if the release (which is organized by the Cetacean Research Center and slated for late June) is successful, it will bring the number of freed dolphins in the past three years to seven.

"These efforts are demonstrating the feasibility of rehabilitating and releasing dolphins and whales who have been in captivity for several years," says Lori Marino, executive director of the Kimmela Center for Animal Advocacy.

"They stand as a very real challenge to arguments from marine parks that wild-caught dolphins and whales cannot be released," Marino says. (See "Lori Marino: Leader of a Revolution in How We Perceive Animals.")

"The idea of rehab and release, or sea-pen retirement sanctuaries, is gaining momentum. It is the next critical phase in advocacy for captive marine mammals."

A Second Chance

Taesan, a male, and Boksoon, a female, have lived in captivity for some five years. They were among a number of bottlenose dolphins illegally captured in 2009 and 2010 and sold to Jeju's Pacific Land entertainment park.

In March 2013, South Korea's Supreme Court, following a protracted legal battle, ordered Pacific Land to give up four illegally caught dolphins (including Taesan and Boksoon). Two, Sampal and Chunsam, along with a third dolphin from the Seoul Grand Zoo called Jedol, were rehabilitated in pens off Jeju and released in July 2013. (See more pictures of dolphins living in captivity.)

Taesan and Boksoon were deemed too ill and lethargic for release at the time. But following two years of care at the Seoul Grand Zoo, they are now being given their chance to join Sampal, Chunsam, and Jedol in their native pod, a group of about 120 dolphins that spends most of its time in the waters off Jeju.

"You need to try and return them to the place they were taken, and the closer the better," says Naomi Rose, a marine mammal scientist with the Animal Welfare Institute, who was a consultant to the 2013 Korean dolphin release. "And ideally you would actually know their genetic population."

Not Out of the Woods

Before the gates on their sea-pen are opened, Taesan and Boksoon must be healthy and show that they have regained the ability to forage for live prey. They also must demonstrate at least some of the physical fitness dolphins in the wild need to stay on the move and make repeated dives.

Human contact will also be minimized, to reduce the association between humans and food, and reorient the dolphins toward their undersea world.

According to Rose, however, every dolphin is different, and Taesan's and Boksoon's poor condition in captivity might mean that it will be more difficult to successfully reintegrate them into the wild. (Also see "Q&A: National Aquarium CEO Discusses Dolphins' Retirement.")

"Everything is case by case, and you should never prejudge the success of a second attempt based on the first," she notes. "If it looks like they are struggling, I hope they have a contingency plan to rescue them and care for them."

Last to Be Set Free?

An estimated 2,900 dolphins live in captivity around the world, the majority of them born and captured in the wild. (See graphic: "Captive Performers.")

Many would be candidates for rehabilitation and release, but apart from the high cost (which can easily run hundreds of thousands of dollars), Taesan and Boksoon could well be the last captive dolphins released for the foreseeable future.

"We cannot continue to do this work if the marine-park industry continues to hold onto the animals, and is reluctant to recognize that this is a viable option for dolphins," Rose says.

"This is not a trend until more good candidates are made available."

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