Humpback whales, once hunted nearly to the point of extinction, are rebounding. In 2005, 20,000 whales were counted in the North Pacific, and they're increasing at a rate of 7 to 8 percent a year. A humpback research group, The Eye of the Whale, estimates the population is approaching pre-whaling numbers.

The Eye of the Whale has documented two "clans" of whales in Prince William Sound. One, called the "Old Ladies," includes two females often seen swimming side by side. Because of their drooping tails, the whales are estimated to be at least 70 years old. Humpbacks typically live 45 to 100 years.

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