A tiger lurked in the tall grass at a park in India as gamekeepers tried to shoot it with a dart gun and missed. The animal suddenly sprang from the grass, sailed through the air and took a swipe at a man sitting on an elephant’s back.

The man lost three fingers.

“I could never imagine that a tiger could so effortlessly leap from the ground onto an adult elephant’s head, which is at least 12 feet above the ground,” Vivek Menon, executive director of Wildlife Trust of India, said of the 2004 attack, a video of which has been circulating on YouTube.

That attack – along with other examples of explosive encounters with tigers – are stoking a debate that began after a 350-pound Siberian tiger climbed over the 12 1/2-foot wall around its pen at the San Francisco Zoo on Christmas Day and mauled three visitors, killing one.

Among the questions experts are now asking: How high can tigers jump? And have zoos and sanctuaries dangerously underestimated tigers?

That is to say: Are the walls high enough?

“We are evaluating that right now,” said Vernon Weir, director of the American Sanctuary Association, which has about 35 members, only a few of which have big cats. The ASA accredits sanctuaries and in the past recommended 12-foot fences.

Similarly, the Association of Zoos & Aquariums, which accredits the nation’s zoos, may adjust its 16.4-foot wall-height recommendation for tigers once it learns fully what happened in San Francisco, spokesman Steve Feldman said.

In San Francisco, the wall was well below the AZA minimum. But several other major U.S. zoos appear to meet or exceed the standards, with high walls topped in many cases with electrified wire or pronounced overhangs to prevent tigers from pulling themselves up and over the side.

Animal experts said they aren’t aware of any hard numbers about the precise leaping ability of tigers. They said it depends on the animal and whether it has been taunted, as may have happened in the San Francisco tragedy. But Feldman said his organization’s 16.4-foot figure was based on the opinions of a group of experts.

There are well-publicized examples of tigers’ phenomenal leaping ability.

In an incident at a national park in Nepal in 1974, an enraged Bengal tiger protecting her cubs mauled a researcher who had climbed into a tree. The tiger managed to climb onto a 15-foot-high limb.

“She just went right up and she didn’t have much to hold onto. She clearly made that jump without much problem,” said Melvin Sunquist, professor of wildlife ecology at the University of Florida and an expert on tigers.

Sunquist, who published an account of the Nepal attack in his book “Tiger Moon: Tracking the Great Cats of Nepal,” said he wasn’t surprised by the news that a tiger had gotten out of its cage in San Francisco.

“I saw what a tigress can do,” he said. “If they can get a purchase on anything, they can get up there.”

Dale Miquelle, director of Wildlife Conservation Society’s program in Russia, said he has seen tigers do many unusual things, such as climbing to the top of large trees when incensed – something tigers don’t normally do.

“What animals normally do and what they can do are often very different things,” Miquelle said.