NEW YORK (Reuters) - Hillary Clinton, who until recently had avoided the spotlight in the wake of her election defeat in November, made a surprise appearance at New York’s Tribeca Film Festival on Saturday as a panelist to discuss illegal elephant poaching.

Andrea Heydlauf (L-R), Chief Marketing Officer for African Parks, Rachel Webber, National Geographic Partners' Executive Vice President of Digital Product, director and writer Imraan Ismail join former U.S. Secretary of State Hillary Clinton attending a panel discussion after the VR screening of National Geographic's "The Protectors: A Walk in the Ranger's Shoes" at the Tribeca Film Festival in New York, April 22, 2017. Photo by Anthony Behar/National Geographic/PictureGroup/Handout via REUTERS

The discussion followed the premiere of Academy Award-winning director Kathryn Bigelow’s virtual reality documentary “The Protectors: Walk in the Rangers’ Shoes.” The eight-minute film allows viewers to experience what it is like to work as a park ranger trying to save elephants in the Democratic Republic of the Congo.

“We’ve got to bust this market,” Clinton said of the global ivory trade.

The unexpected public appearance on Earth Day was one of several Clinton has made recently, following a period of silence after the former Democratic presidential candidate lost the November election to President Donald Trump.

Clinton said she first began focusing on the “horrific slaughter” of elephants when she was secretary of state and later helped launch an anti-poaching initiative at her family’s nonprofit Clinton Global Initiative.

More than 30,000 elephants are killed by poachers every year in Africa.

In addition to endangering vulnerable elephant populations, trafficking also provides financial support to extremist militant groups, Clinton said.

“When we were looking at this, we thought there were three overriding goals: stop the killing, stop the trafficking and stop the demand,” she said.

While China is the world’s biggest market for illegal ivory, the United States ranks No. 2, Clinton said, requiring Americans to take a leading role in fighting elephant poaching.

Clinton also mentioned the March for Science, which took place in Washington and other cities around the world earlier on Saturday. The Earth Day event was in effect a protest against what critics say has been the Trump administration’s disregard for evidence-based knowledge and research.

“Here it is, Earth Day, and we are marching on behalf of science,” Clinton said to applause in the theater.

In early April, Clinton granted her first interview since her defeat by Trump, breaking her silence at the Women in the World Summit in New York. In front of a live audience, she voiced support for U.S. bombing raids on Syrian airfields and said Russian interference in the presidential election was a theft more damaging than Watergate.