Using aerial photographs and online measuring tools to look at Tatiana's grotto, I repeatedly got widths of less than 24 feet.
In other words, the width of the moat most likely does not meet AZA standards, which could hardly be described as overly cautious.
NO MARGIN FOR ERROR
The world soon found out the bank of Tatiana's grotto was less than 12.5 feet high, and experts quickly agreed that a motivated tiger could have surmounted the wall. Yet Mollinedo was still expressing disbelief.
We know tigers pluck monkeys from tree branches, bound over steep rock faces, and jump on the backs of large prey. But how tall do they stand, and how much can they elevate? The best evidence I can find of an Amur's reach comes from the field studies of Anatolii Grigor'evich Yudakov. One way Amurs mark their territory is by making scratches high in the bark of trees. Yudakov measured these marks at 210 to 290 centimeters, or roughly 7 to 9.5 feet.
For an Amur standing on its hind legs to reach the top of a 12.5 foot wall, it would have to elevate another 3 to 5.5 feet. Remember Gretchen jumping effortlessly over the side rail of a small pickup? Four feet.
A major prey species for Amurs is the Manchurian red deer, which stands up to five feet at the shoulder. Though not sourced, many references report a vertical leap for tigers of six feet. Take a tiger with a reach of almost 10 feet and a vertical leap of six feet, and suddenly the industry standard of a 16-foot wall has no appreciable margin for error.
Then there are the events of May 14, 1994, when a Bengal tiger in India's Kaziranga National Park attacked a man on the back of an elephant. According to a press release from Wildlife Trust International, executive director Vivek Menon reviewed footage of the attack and exclaimed, "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."
There has been much speculation about whether a captive tiger is capable of matching the jumping ability of a wild cat. Presumably a confined tiger would be sluggish, out of shape, her muscles atrophied. No one to my knowledge, though, has studied the sports physiology of tigers.
I can say from personal experience that even captive tigers are incredibly agile and powerful. We had a Bengal named Engels (the litter was born on May Day) who lived on Tiger Island. One day a female Bengal tried to snatch some food from him. He swiped at her almost casually, hitting her in the side. The force of the blow immediately stopped the young tiger's heart, and she fell over dead.
THE LONG JUMP
So what happened that day at the Zoo? So far, none of the witnesses are talking. Media accounts suggest one scenario: Tatiana may have stood on her hind legs against the wall, pushed off from the bottom of the moat, grabbed the top of the wall with her front paws, and leveraged herself up and over by digging her hind claws into the wall. That's conceivable, I guess. Tatiana may even have escaped before the attack and waited for her prey in the tall grass beside the moat.
I have a very hard time imagining that, though. For one thing, the wall curves outward at the top. For another, such methodical, incremental movement is not typical of a tiger. They stalk their prey slowly, but in a brutal burst, they close with amazing speed. I am convinced Tatiana exploded from the grotto, landed on the lip, and then powered her way up. Whether she sprang from one of the protruding rocks, the sloped bank, or the moat floor is almost immaterial, but I am inclined to believe she jumped over the moat.
Strangely, Mollinedo may have been on the right track at a Dec.