The number of blue whales feeding off the coast of California is on the rise. A new count shows that there are about 2,200 individuals in the area, which represents roughly 97 percent of the prewhaling population. The results, published September 5 in Marine Mammal Science, are good news for this population of blue whales. But questions remain about whether other populations, such as the one hunted off the coast of Japan in the early 1900s, have been killed off forever or could rebound as well.