The Nonindigenous Occurrences section of the NAS species profiles has a new structure. The section is now dynamically updated from the NAS database to ensure that it contains the most current and accurate information. Occurrences are summarized in Table 1, alphabetically by state, with years of earliest and most recent observations, and the tally and names of drainages where the species was observed. The table contains hyperlinks to collections tables of specimens based on the states, years, and drainages selected. References to specimens that were not obtained through sighting reports and personal communications are found through the hyperlink in the Table 1 caption or through the individual specimens linked in the collections tables.

Crassostrea gigas
Crassostrea gigas
(Pacific giant oyster)

Copyright Info
Crassostrea gigas

Common name: Pacific giant oyster

Synonyms and Other Names: Magallana gigas

Taxonomy: available through www.itis.govITIS logo

Native Range:
Hydrologic Unit Codes (HUCs) Explained
Interactive maps: Point Distribution Maps

Nonindigenous Occurrences:

Table 1. States with nonindigenous occurrences, the earliest and latest observations in each state, and the tally and names of HUCs with observations†. Names and dates are hyperlinked to their relevant specimen records. The list of references for all nonindigenous occurrences of Crassostrea gigas are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
AK193919803Cook Inlet; Ketchikan; Prince William Sound
CA1928201711Cottonwood-Tijuana; Mad-Redwood; Monterey Bay; Newport Bay; San Diego; San Francisco Bay; San Gabriel; San Luis Rey-Escondido; San Pablo Bay; San Pedro Channel Islands; Tomales-Drake Bays
HI192619942Hawaii; Oahu
WA187520106Dungeness-Elwha; Hood Canal; Puget Sound; Queets-Quinault; Strait of Georgia; Willapa Bay

Table last updated 4/16/2024

† Populations may not be currently present.

Impact of Introduction:
Summary of species impacts derived from literature review. Click on an icon to find out more...


Other Resources:
Crassostrea spp. (ANS Clearinghouse Bibliography)

Author: Elder, N.E.

Revision Date: 3/5/2021

Citation Information:
Elder, N.E., 2024, Crassostrea gigas: U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=113, Revision Date: 3/5/2021, Access Date: 4/16/2024

This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.


The data represented on this site vary in accuracy, scale, completeness, extent of coverage and origin. It is the user's responsibility to use these data consistent with their intended purpose and within stated limitations. We highly recommend reviewing metadata files prior to interpreting these data.

Citation information: U.S. Geological Survey. [2024]. Nonindigenous Aquatic Species Database. Gainesville, Florida. Accessed [4/16/2024].

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