Humpbacks forage by blowing bubble nets around schools of fish and then lunging through them. But in 1980, someone saw a single humpback living in the Gulf of Maine modify this behavior to include using its tail. It was a new strategy developed after a primary food source, herring, became depleted. The whale struck the water with its fluke a few times, and then did the bubble-feeding method to feast on a different fish, called sand lances. This is now known as lobtail feeding, and in the next few years, researchers noticed more and more whales adopting it--by 2007, some 40 percent of the population was doing it.