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.

Chanos chanos
Chanos chanos
Marine Fishes
Native Transplant

Copyright Info
Chanos chanos (Forsskål, 1775)

Common name: Milkfish

Taxonomy: available through www.itis.govITIS logo

Identification: A few distinguishing characteristics and a discussion of similar species were given by Eschmeyer et al. (1983). A photograph and distinguishing characteristics were given in Burgess and Axelrod (1974). This fish's taxonomy and morphology have been summarized recently by Bagarinao (1994). The species resembles a toothless herring with a deeply forked tail fin.

Size: 150 cm.

Native Range: Tropical marine. Widespread in Pacific and Indian oceans from the eastern coast of Africa to the tropical western coast of the Americas (Berra 1981; Bagarinao 1994).

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 Chanos chanos are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
CA187619822San Diego; Suisun Bay

Table last updated 6/15/2024

† Populations may not be currently present.

Means of Introduction: The Solano County, California, introduction of 1877 consisted of about 100 fish from Hawaii (in exchange for salmon and trout eggs) that were stocked by the California Fish and Game Commission (Duffy and Bernard 1985).

Status: An attempt by the state to stock these fish in inland waters of California in 1877 apparently failed. Other records are from coastal marine habitats; furthermore, these reports most likely represent natural strays and not introductions.

Impact of Introduction: The impacts of this species are currently unknown, as no studies have been done to determine how it has affected ecosystems in the invaded range. The absence of data does not equate to lack of effects. It does, however, mean that research is required to evaluate effects before conclusions can be made.

Remarks: Hubbs et al. (1979) listed Chanos chanos as having been introduced but not established in California. However, Berra (1981) and Bagarinao (1994) included the California coast in the species' native range. Reports of milkfishes from San Pedro and San Diego bays in 1929 and 1979 and between 1982 and 1983 are likely the result of natural strays from Mexican populations (Duffy and Bernard 1985; Bagarinao 1994). There is no mention of Chanos chanos in inland waters of California by Moyle (1976a) or by Swift et al. (1993).

Voucher specimens: California (SIO 82-22, LACM 42887-1).

References: (click for full references)

Bagarinao, T. 1994. Systematics, distribution, genetics and life history of milkfish, Chanos chanos. Environmental Biology of Fishes 39:23-41.

Berra, T. M. 1981. An atlas of distribution of the freshwater fish families of the world. University of Nebraska Press, Lincoln, NE.

Burgess, W. E., and H. R. Axelrod. 1974. Pacific marine fishes book 4: fishes of Taiwan and adjacent waters. Tropical Fish Hobbyist Publications, Inc., Neptune City, NJ.

Duffy, J. M., and H. J. Bernard. 1985. Milkfish, Chanos chanos (Forsskål, 1775), taken in southern California adds new family (Chanidae) to the California marine fauna. California Fish and Game 71:122-125.

Eschmeyer, W. N., E. S. Herald, and H. Hamann. 1983. A field guide to Pacific Coast fishes of North America. Peterson Field Guide Series. Houghton Mifflin Co., Boston, MA.

Hubbs, C. L., W. I. Follett, and L. J. Dempster. 1979. List of the fishes of California. California Academy Science Occasional Papers 133. 51 pp.

Moyle, P. B. 1976. Inland fishes of California. University of California Press, Berkeley, CA.

Shapovalov, L., A. J. Cordone, and W. A. Dill. 1981. A list of freshwater and anadromous fishes of California. California Fish and Game 67(1):4-38.

Smith, H. M. 1896. A review of the history and results of the attempts to acclimatize fish and other water animals in the Pacific states. Pages 379-472 in Bulletin of the U.S. Fish Commission, Vol. XV, for 1895.

Swift, C. C., T. R. Haglund, M. Ruiz, and R. N. Fisher. 1993. The status and distribution of the freshwater fishes of southern California. Bulletin of the Southern California Academy of Science 92(3):101-167.

Other Resources:
FishBase Summary

Author: Nico, L.

Revision Date: 9/4/2019

Peer Review Date: 5/16/2000

Citation Information:
Nico, L., 2024, Chanos chanos (Forsskål, 1775): U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/factsheet.aspx?SpeciesID=413, Revision Date: 9/4/2019, Peer Review Date: 5/16/2000, Access Date: 6/15/2024

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.


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Citation information: U.S. Geological Survey. [2024]. Nonindigenous Aquatic Species Database. Gainesville, Florida. Accessed [6/15/2024].

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