CORVALLIS - A book about alien invaders with hideous green claws and eyes on stalks, silently and insidiously moving in on the unsuspecting locals of some obscure backwater - must be a pulp science fiction novel, right?

Wrong. The new volume from Oregon Sea Grant tells the story of a real invader, one that is poised to cause serious trouble in the waters of the Pacific Northwest, just as it has in many other places around the world.

Oregon Sea Grant has published "Global Invader: The European Green Crab," by Sylvia Behrens Yamada. The 140-page book costs $15 and is available by writing to Sea Grant Communications, Oregon State University, 322 Kerr Administration Building, Corvallis, 97331-2131; calling 541-737-2716; faxing 541-737-7958; or sending e-mail to

The European green crab, Carcinus maenus, well deserves its reputation as an international troublemaker. The crab is able to tolerate air exposure, starvation and wide ranges in temperature and salinity. It was introduced from Europe to the Atlantic coast of the U.S. almost 200 years ago and now ranges from Virginia to the southern shores of Canada's Prince Edward Island, resisting repeated efforts to eradicate it. It has spread from its European home to the southern tip of Africa, the shores of Australia and off the coast of Japan.

It was first discovered on the Pacific coast of the United States in 1989, near San Francisco Bay. It had established itself in the Pacific Northwest by 1998 and continues to spread.

Word of the European green crab's arrival in Northwest waters was troubling news to the region's fishers, ecologists, fishery managers and others. The invader is a voracious predator. It muscles out native crab species and makes it difficult for young bivalves, urchins and barnacles to establish themselves. Researchers fear that the green crab's growth in the Northwest will have serious ecological and economic effects.

Yamada's book describes the biology and life history of the European green crab, presents five case studies of green crab invasions and discusses the crab's ecological and economic impact on the Pacific Northwest. It includes line drawings and color plates of the European green crab as well as many native Northwest species for comparison.

Although directed at fishers, Extension agents, fishery managers and others who need to recognize green crabs in the course of their work, the book will also be of interest to researchers and others interested in invasive species and the Pacific Northwest coast.

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Sandy Ridlington, 541-737-0755