Yep, it turns out that the San Francisco Bay has more non-native species in it than any other place on the planet:
Asian clams, Chinese mitten crabs, Amur River clams, New Zealand carnivorous sea slugs, Black Sea jellyfish and Japanese gobies are just a few of the exotics that have ended up in San Francisco Bay, usually transported in ships' ballast water.
The study looked at the globe, with researchers combing through more than 350 databases and other sources for information. The study showed 85 invasive species in the bay, with 56 considered "harmful" - meaning they have an ecological impact, spread easily and are difficult to manage.