"An Underwater Fight Is Waged for the Health of San Francisco Bay"

"SAN FRANCISCO -- Chela Zabin will not soon forget when she first glimpsed the golden brown tentacle of the latest alien to settle in the fertile waters of San Francisco Bay.

'I had that moment of "Oh God, this is it, it's here,
' said Dr. Zabin, a biologist with the Smithsonian Environmental Research Center. 'I was really hoping I was wrong.'

The tentacle in question was that of an Asian kelp, Undaria pinnatifida, a flavorful and healthful ingredient in miso soup and an aggressive, costly intruder in waters from New Zealand to Monterey Bay.

The kelp, known as wakame (pronounced wa-KA-me), is on a list of '100 of the World's Worst Invasive Alien Species,' compiled by the Invasive Species Specialist Group. Since her discovery in May, Dr. Zabin and colleagues have pulled up nearly 140 pounds of kelp attached to pilings and boats in the San Francisco Marina alone."

Malia Wollan reports for the New York Times August 1, 2009.