SAN FRANCISCO (KCBS) – Friday marks World Elephant Day, and the San Francisco Zoo is calling attention to the illegal ivory trade.

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There is lots of work to be done in California, as the Bay Area and Los Angeles are among the largest markets for ivory in the U.S.

Its estimated that 100 elephants are killed daily for their tusks. Despite not having an elephants on display, the zoo does have other animals also prized for their horns.

“We do have black rhinos and hippos that are also subject to the illegal trade. So we felt it’s important for us to get involved,” SF Zoo director Tanya Peterson told KCBS. “Moreover, we know that San Francisco is one of the offending cities in purchasing new ivory, and so that’s why we felt we need to educate our community.”

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The pledge is to not buy new ivory. According to Zoo supporter John McNellis, an ivory tusk can sell for $100,000 on the open market.

“So if we can do just a little bit to help here, people are doing this across the world now, but we need to do our part,” McNellis said.

Supervisor Norman Yee grew up in Chinatown. Yee said many value carved tusks for luck and as an art form, but education is needed to learn about the connection to a dead elephant.

“I saw ivory as I was growing up, never thought anything about that. So I was one that needed education to be aware that these animals don’t deserve to die,” Yee said.

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The anti-ivory pledge can be signed at sfzoo.org.