Invasive species

It is estimated that at least nine non-native species of marine plants and 83 species of marine animals have been introduced into Puget Sound. Some of these were intentionally introduced, such as the Pacific oyster and Manila clam, to substitute for the loss of native shellfish species. Other animals have arrived through ship ballast water and other accidental introductions.

Sources:

Sound Science 2007

Addition resources:

Encyclopedia of Puget Sound list of invasive speciesWashington Invasive Species CouncilUSGS non-indigenous aquatic speciesWA Noxious Weeds Control BoardWDFW prohibited aquatic animals species list

The invasive tunicate Styela clava. Photo: WDFW

OVERVIEW

Intentional and unintentional introduction of invasive and non-native species

Non-native species are those that do not naturally occur in an ecosystem. A non-native species is considered invasive when it is capable of aggressively establishing itself and causing environmental damage to an ecosystem. Plants, animals, and pathogens all can be invasive. 

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