Blue Whales' Comeback
23 Sep 2014
Researchers believe that California blue whales have recovered in numbers and the population has returned to sustainable levels.
Scientists say this is the only population of blue whales to have rebounded from the ravages of whaling.
The research team estimate that there are now 2,200 of these giant creatures on the eastern side of the Pacific Ocean.
But concerns remain about their vulnerability to being struck by ships.
At up to 33m in length and weighing in at up to 190 tonnes, blue whales are the largest animals on the planet.
The California variety is often seen feeding close to the coast of the state, but they are found all the way from the Gulf of Alaska down to Costa Rica.