(Astoria, OR) -- A Chinese mitten crab was caught in the Lower Columbia River last week. The species is prohibited in Oregon and none have been confirmed in the Pacific Northwest until now. It was discovered by a commercial fisherman, who noticed the unusual looking crab. ODFW says he did the right thing bringing it to the state's attention. The single male crab could have been introduced by someone or via ballast water as larvae. Mitten crabs can cause significant infrastructure and ecological damage, and have done so in and around the San Francisco Bay.