A group of animal rights activists staged a demonstration Saturday at Hong Kong’s Ocean Park to protest dolphin shows as part of their annual “Empty the Tanks’ campaign against holding marine animals in captivity.

Protesters railed against the “captivity industry,” carrying signs with slogans like “Not a Park, a Prison.” Campaign propaganda said that the sixth annual “Empty the Tanks” protest would be taking place in nearly 70 locations in 23 different countries.

According to its website, Empty the Tanks was founded as “a way to speak out for the captive dolphins and whales languishing in tanks all around the world.”

One demonstrator, Claudia Mo, told local television that “animal shows should have no place in the world” because marine mammals are highly intelligent creatures and “they are exploited to entertain humans.”

“That’s animal slavery, and it’s so wrong,” she said.

Among their demands, activists have called on Ocean Park to phase out animal shows and artificial breeding, insisting that nothing about the park is natural and so visitor obtain no educational benefit from seeing animals in a captive setting.

Marine mammals in tanks “are not eating, socializing, reproducing, exercising, or behaving naturally. Everything you see at a marine park or aquarium is a forced behavior,” protest organizers said.

They also requested that the park establish a public notification system concerning any injuries and deaths of its animals.

The marine park brought out extra security on Saturday, but apart from a brief scuffle, the demonstrators remained peaceful.

One group of activists chanted slogans outside Ocean Park such as “dolphins belong to the ocean, not a park,” “Captivity kills,” and “release the dolphins,” under the wary eyes of security guards.

Activists have said that putting a dolphin in a swimming pool-sized tank may seem humane but is the equivalent of confining a human person in a bathtub.

“Cetaceans are literally bored to death in their tanks, which are always tiny in relation to their size and extremely monotonous for them,” said protester Sasha Abdolmajid.

Dora Wong of Civic Party Animal Rights Concern Group criticized Ocean Park for its heightened security and close vigilance over protesters.

“We tried to use peaceful means to tell visitors that Ocean Park’s publicity materials are misleading – that [animal captivity] is actually a cruel practice and deprives animals of their freedom,” she told local television.

Ocean Park responded to the protest with a statement asserting that some of the protesters’ claims were “misinformed.” Releasing the dolphins is “unrealistic,” the park said, since the majority of the park’s dolphins were born in captivity and are ill-equipped for life in the wild.

The park also said that artificial breeding helps prevent extinctions, adding that the park has helped finance global conservation efforts and furnished rehabilitation facilities for injured or orphaned cetaceans.

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