英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—21

Blizzardcam nearly met its match with the most playful bear it's ever encountered. The bear wanted to know how it worked. Blizzardcam deployed snowballcam as a decoy. This was the polar bears' favorite spy camera and this young male was no exception.

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—20

The mother and cub are thrown a lifeline by a change in the weather and ocean currents. It is a huge swim out to the ice floes for the little cub. He finally makes it to the ice, nine months after he was born. His mother has triumphed against the odd

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—19

Finally she leaves him some scraps to chew on. A young male arrives, a dangerous situation for the cub. She growls a warning. Its not enough. The cub slips. The mother must get her cub away from danger as quickly as possible. They head north. She kno

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—18

Calcium from the bones will help the mother's milk supply, but the cub needs meat to survive. Now they have another problem. Other bears can't be trusted with small cubs. But fortunately they seem more interested in what lies beneath the surface. It

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—17

At last, there is hope. They have finally reached the pack-ice that forms the polar icecap. Its the ultimate hunting habitat for polar bears. The icecap stretches all the way to the North Pole. Seals are found wherever it meets the sea. Its been a lo

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—15

Time for kick off. It's polar bear football. Their ball control needs practice. But they are experts at dribbling. The game descends into argument. The spycams return to the benches, the bears may be play-fighting, but things still get out of hand. M

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—14

This is a high-risk strategy. Like the male at the whale carcass, some bears don't do sharing. She stands up to make herself look bigger. The cub copies. Luckily, this bear has no appetite for a fight. There is a feeding etiquette around a seal carca

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—13

If it hasn't already been seen, that is. The bears at the whale carcass are in food heaven, but their peace is about to be shattered. This male heavyweight prefers to eat alone. He is bigger than the other bears and likes to throw his weight around.

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—12

They continually chatter away to each other. It's all about keeping aggression under control. Their massive claws rake the skin like knives, cutting it into strips. At two years old, this bear is testing his status, standing up to other bears. Sharin

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—11

Back on Svalbard, it's high summer. Barnacle geese that had overwintered in Scotland have started to breed. Their calls bring hope to hungry bears. The cub stays back as his mother explores the possibilities. Bears have only recently discovered this

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—10

Every hunt presents a different challenge, so he plans a new strategy each time. He slinks into the water, using a channel between the ice floes to act as cover. He swims, hardly making a sound, reaching six miles per hour at times. His front legs pr

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—9

Its seaweed. Kelp is not wildly exciting, but it does contain carbohydrates and some protein too. The cub must find acrobatics rather strange. Hungry bears eat virtually anything. Its a question of making the most of whats around, and its never too s

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—8

This new and ever-changing world requires a different spy-camera, iceberg-cam. It effortless steers between ice sheets and its turret rotates to follow the bears. The bear's lives are now governed by the state of the drifting ice and the movement of

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—1

The islands of Svalbard in Arctic Norway. They might be remote, but they are under surveillance. Spy cameras are capturing the most intimate images ever taken of polar bears. They're revealing some remarkable behavior and discovering an animal of sur

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—2

She pushes the camera down the slope, a tracking shot. As she films, there is no human presence of any kind. She even adjusts the camera to record her own exit. She must get her cub to the sea-ice before it breaks up and thaws, otherwise, they will b

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—3

She blinks in the sunlight. She spent her confinement in semi-darkness. She checks that the coast is clear and then reveals her secrets. Time for a stretch. She's been cooped up with her cubs since she gave birth three months ago. They learn by examp

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—4

But polar bear courtship is never straightforward. She likes to play hard-to-get. It's also a challenge for blizzardcam. She's testing his fitness, making sure he is a good catch. He skills on the slopes show room for improvement. And now, the female

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—5

She's aware of his difficulties and uses her body as a shield. She must stay attentive if her cub is to survive in this harsh Arctic world. Realizing he's exhausted, she digs a hollow to rest him. In the dens like this, she suckles him six times a da

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—6

But again, a bear helps with the filming. Sealed with a kiss, the couples whirlwind romance will last three weeks. Out on the frozen sea, a young male has killed a seal. He caught it when it surfaced through a breathing hole in the ice. To film from

英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—7

She leaves little behind. Males are still on the lookout for females. For her cub's safety, she heads back to the hills. But as spring continues, lengthening days bring sudden and dramatic change. The highest tides of the year combine with the rising