Blue whales may get boost from ocean fertilization program

March 24 (Bloomberg) -- The blue whale, the largest animal on Earth, may be saved from extinction with help from an ocean- fertilization experiment in the seas off Antarctica that has sparked growth of its main food source.

Dumping a by-product of metal processing, iron sulfate, into the ocean stimulates the growth of plankton, which is consumed by krill, said Victor Smetacek of Germany's Alfred Wegener Institute for Polar and Marine Research. Adult blue whales eat about 4 tons of the shrimp-like animal daily.

"Fertilizing the feeding grounds is analogous to creating water holes in the desert," Smetacek, who led a research expedition to the South Atlantic this year to test a theory that fertilizing the ocean can help reduce carbon-dioxide emissions, said yesterday in an interview. "It's ecosystem restoration."

The blue whale, which averages 25 feet (7.6 meters) at birth, is listed as endangered by the International Union for Conservation of Nature of Switzerland. Japan conducts an annual hunt in the northern Pacific and Southern Ocean using a loophole in a 1986 global whaling moratorium that allows "lethal research" on whales.

What Japan's government refers to as a research hunt began in 1987 and kills minke and fin whales. Japan's plan to hunt humpback whales was postponed in 2007 after protests from New Zealand and Australia. The program also takes skin and blubber samples of blue and other whales using non-lethal methods.

The population of blue whales, which can reach 105 feet in length with tongues weighing as much as an elephant, has declined up to 90 percent the past century, the IUCN said. Blue whales were heavily hunted until a worldwide ban in 1966.

"We have a solution to saving the whales why wouldn't we want to use it?" Smetacek said in Berlin.

Conservationists Balk

Conservationists today questioned whether staving off the extinction of blue whales, which can weigh about 200 tons and have an average lifespan in the wild of 80 to 90 years, is simply a matter of dumping iron sulfate in the ocean.

Fertilizing the seas with iron may even violate international agreements on marine protection, said Stephan Lutter, a marine policy expert at World Wildlife Fund in Hamburg. Promoting algae growth with fertilization can also result in eutrophication, or a proliferation of plant life that reduces oxygen content in water and eliminates other sea life.