Disclaimer:

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.

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Common name: Delta Smelt

Taxonomy: available through www.itis.gov

Identification: Moyle (1976); Page and Burr (1991).

Size: 20 cm.

Native Range: Endemic to Sacramento-San Joaquin delta region of central California (Page and Burr 1991).

Alaska	Hawaii	Puerto Rico & Virgin Islands	Guam Saipan

Native range data for this species provided in part by NatureServe

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

Ecology: Delta Smelt are small, euryhaline fish primarily occuring in shallow, low-salinity regions of the San Francisco Estuary. Delta Smelt are planktivorous, primarily feeding on planktonic crustaceans. Spawning takes place in spring to early summer in sloughs of the upper estuary (Moyle 2002).

Means of Introduction: Intentionally stocked as forage (Sigler and Sigler 1987).

Status: Extirpated by 1996 (Sigler and Sigler 1996).

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.

References: (click for full references)

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

Moyle, P.B. 2002. Inland fishes of California. 2nd edition. University of California Press, Berkeley, CA.

Page, L.M., and B.M. Burr. 1991. A field guide to freshwater fishes of North America north of Mexico. The Peterson Field Guide Series, volume 42. Houghton Mifflin Company, Boston, MA.

Sigler, W.F., and J.W. Sigler. 1987. Fishes of the Great Basin: a natural history. University of Nevad Press, Reno, NV.

Sigler, W.F., and J.W. Sigler. 1996. Fishes of Utah: a natural history. University of Utah Press, Salt Lake City, UT.

Other Resources:

Author: Pam Fuller, and Matt Neilson

Peer Review Date: 12/2/2011

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.