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.

Alosa sapidissima
Alosa sapidissima
(American Shad)
Native Transplant

Copyright Info
Alosa sapidissima (Wilson, 1811)

Common name: American Shad

Taxonomy: available through www.itis.govITIS logo

Identification: Smith (1985); Whitehead (1985); Page and Burr (1991); Jenkins and Burkhead (1994).

Size: 75 cm.

Native Range: Atlantic Coast from the Sand Hill River, Labrador, to the St. Johns River, Florida; ascends coastal rivers to spawn (Page and Burr 1991).

Native range data for this species provided in part by NatureServe NS logo
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 Alosa sapidissima are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
AL187619022Cahaba; Upper Alabama
AK1891200224Admiralty Island; Anchorage; Baranof Island; Bering Glacier; Burroughs Bay; Chilkat-Skagway Rivers; Cook Inlet; Etolin-Zarembo-Wrangell Islands; Glacier Bay; Ketchikan; Kodiak-Afognak Islands; Lower Copper River; Lower Kenai Peninsula; Lower Susitna River; Lynn Canal; Matanuska; Middle Copper River; Port Heiden; Prince of Wales; Prince William Sound; Stikine River; Thomas Bay; Upper Kenai Peninsula; Yakutat Bay-Gulf of Alaska
AZ188418861Havasu-Mohave Lakes
AR187618761Upper White-Village
CA1871202026Honcut Headwaters-Lower Feather; Lower American; Lower Eel; Lower Klamath; Lower Sacramento; Lower Sacramento; Mad-Redwood; Monterey Bay; Oregon, Washington, Vancouver Coast and Shelf; Russian; Sacramento Headwaters; San Diego; San Gabriel; San Joaquin Delta; San Pablo Bay; Santa Barbara Coastal; Santa Monica Bay; Smith; Suisun Bay; Thomes Creek-Sacramento River; Tomales-Drake Bays; Upper Coon-Upper Auburn; Upper Mokelumne; Upper San Joaquin; Upper Stanislaus; Upper Yuba
CO187218722Middle South Platte-Cherry Creek; Upper South Platte
FL190019005Apalachicola; Aucilla; Florida Southeast Coast; Lower Ochlockonee; Lower Suwannee
GA190019001Lower Flint
ID189119903Bear Lake; Lower Snake-Asotin; Upper Snake-Rock
IL187118743Lake Michigan; Little Calumet-Galien; Lower Rock
IN187218743St. Joseph; Upper Wabash; Upper White
IA187418742Lower Des Moines; Middle Des Moines
MI187318745Detroit; Lower Grand; Raisin; Shiawassee; St. Joseph
MN187218721Twin Cities
MS187518762Little Tallahatchie; Middle Pearl-Strong
NE187318731Lower Elkhorn
NV194620011Havasu-Mohave Lakes
NY187019854Chaumont-Perch; Lake Ontario; Niagara River; Upper Allegheny
NC198019801Upper Broad
OH1870190012Ashtabula-Chagrin; Black-Rocky; Cedar-Portage; Cuyahoga; Huron-Vermilion; Lake Erie; Muskingum; Sandusky; Tuscarawas; Upper Great Miami, Indiana, Ohio; Upper Ohio-Shade; Upper Scioto
OR1876201916Alsea; Coos; Coquille; Lower Columbia; Lower Columbia-Clatskanie; Lower Columbia-Sandy; Lower Rogue; Lower Willamette; Middle Columbia-Hood; Middle Columbia-Lake Wallula; Middle Willamette; Oregon, Washington, Vancouver Coast and Shelf; Siletz-Yaquina; South Umpqua; Umpqua; Upper Willamette
PA187319622Lower Monongahela; Youghiogheny
SC199119911Lower Catawba
TN187518766Hiwassee; Holston; Lower Cumberland-Sycamore; Lower Hatchie; Middle Tennessee-Chickamauga; South Fork Forked Deer
TX187419922Austin-Travis Lakes; Lower Brazos
UT187118965Bear Lake; Great Salt Lake; Lower Weber; Middle Bear; Utah Lake
VT187318744Lamoille River; Missiquoi River; Otter Creek; Winooski River
VA187318731Upper New
WA1876200417Dungeness-Elwha; Grays Harbor; Hoh-Quillayute; Hood Canal; Lower Columbia; Lower Columbia-Clatskanie; Lower Snake; Lower Snake; Middle Columbia-Hood; Middle Columbia-Lake Wallula; Pacific Northwest Region; Puget Sound; Queets-Quinault; Strait of Georgia; Upper Columbia-Entiat; Walla Walla; Willapa Bay
WV187319953Greenbrier; Raccoon-Symmes; Upper Kanawha
WI187320002Lake Michigan; Lower Fox

Table last updated 6/15/2024

† Populations may not be currently present.

* HUCs are not listed for states where the observation(s) cannot be approximated to a HUC (e.g. state centroids or Canadian provinces).

Means of Introduction: This species was stocked intentionally in California starting in 1871 (Dill and Cordone 1997), and then spread to Oregon, Washington, and Alaska. It was intentionally stocked in many other areas as well, for forage, food, sport, and commercial fishing. It was accidentally stocked in Nebraska (Smith 1896).

Status: Established in coastal states, including; Alaska, California, Idaho (Snake River), Oregon, Virginia, and Washington. Stocked but extirpated in Arizona, Arkansas, Idaho (Bear Lake and Bear River), Iowa, Kansas, Illinois, Louisiana, Massachusetts, Minnesota, Mississippi, Nebraska, Nevada, Ohio, Pennsylvania, Tennessee, Texas, Utah, West Virginia, and Wisconsin. Large spawning runs observed in Oregon and Washington as early as 1876 (Smith 1896; Moyle 1976; Wydoski and Whitney 1979).

Impact of Introduction: A study of A. sapidissima in the Umpqua and Willamette rivers in Oregon revealed that they were infected by the nematode Anisakis simplex, which could pose a health risk to native wildlife and even human consumers if they are undercooked (Shields et al. 2002).

American Shad were introduced into the Columbia River over a century ago and now maintain the largest population known to exist in the world. The presence of so many American Shad likely result in competitive pressures against native salmonids, although no studies have been conducted to quantify those effects (Sanderson et al. 2009). Shad may also compete with other native fishes for space, and could cause migratory delays in salmonids and other anadromous fishes (Hasselman et al. 2012b).

Haskell et al. (2006) studied the zooplankton in the Columbia River during the outmigration of subyearling American Shad and Chinook Salmon. They found that shad eat Daphnia as a major food item. At times the Daphnia disappear from John Day Reservoir. Subyearling Chinook also depend on Daphnia. Because of the large increase in abundance of shad from 1980 to 1994, and the pressure they put on the Daphnia population, they reasoned that the salmon may be affected by these Daphnia declines.

Remarks: Intensive stocking took place in the 1800s in eastern coastal states where populations had declined from overharvesting (Ferguson 1876; Baird 1878; Morse 1905). One such example is the Delaware River, Pennsylvania, which was stocked to help the overfished population recover (Morse 1905). Dill and Cordone (1997) provided a detailed account of shad introductions in California. A small commercial fishery exists for them in the Columbia River. Hasselman et al. (2012a) reviewed the introduction of Americ an Shad to the Pacific Northwest, and some of the factors thought to have enhanced the success of introduction and disperal in this region. Hinrichsen et al. (2013) analyzed the effects of habitat disturbances on the abundance of American Shad in the Columbia River basin, suggesting that dam/reservoir construction (and their associated changes in thermal and water flow patterns) has enhanced American Shad distribution and abundance in the region.

References: (click for full references)

Baughman, J. L. 1950. Random notes on Texas fishes. Texas Journal of Science 2:117-138.

Chapman, W.M. 1942. Alien fishes in the waters of the Pacific Northwest. California Fish and Game. 28(1): 9-15.

Cudmore-Vokey, B. and E.J. Crossman. 2000. Checklists of the fish fauna of the Laurentian Great Lakes and their connecting channels. Can. MS Rpt. Fish. Aquat. Sci. 2500: v + 39p.

Deacon, J. E., and J. E. Williams. 1984. Annotated list of the fishes of Nevada. Proceedings of the Biological Society of Washington 97(1):103-118.

Ferguson, T. B. 1876. Report of the Commissioners of Fisheries of Maryland to the General Assembly. 1 January 1876. John F. Wiley, Annapolis, MD.

Hartel, K. E. 1992. Non-native fishes known from Massachusetts freshwaters. Occasional Reports of the Museum of Comparative Zoology, Harvard University, Fish Department, Cambridge, MA. 2. September. pp. 1-9.

Haskell, C.A., K.F. Tiffan, and D.W. Rondorf. 2006. Food habits of juvenile American shad and dynamics of zooplankton in the lower Columbia River. Northwest Science 80(1):47-64.

Hasselman, D.J., R.A. Hinrichsen, B.A. Shields, and C.C. Ebbesmeyer. 2012a. The rapid establishment, dispersal, and increased abundance of invasive American shad in the Pacific Northwest. Fisheries 37(3):103-114.

Hasselman, D.J., R.A. Hinrichsen, B.A. Shields, and C.C. Ebbesmeyer. 2012b. American shad of the Pacific coast: a harmful invasive species or benign introduction. Fisheries 37(3):115-122.

Hendricks, M. L., J. R. Stauffer, Jr., C. H. Hocutt, and C. R. Gilbert. 1979. A preliminary checklist of the fishes of the Youghiogheny River. Chicago Academy of Sciences, Natural History Miscellanea 203:1-15.

Hinrichsen, R.A., D.J. Hasselman, C.C. Ebbesmeyer, and B.A. Shields. 2013. The role of impoundments, temperature, and discharge on colonization of the Columbia River basin, USA, by nonindigenous American Shad. Transactions of the American Fisheries Society 142(4):887-900. http://dx.doi.org/10.1080/00028487.2013.788553.

Howells, R. G. 1992a. Annotated list of introduced non-native fishes, mollusks, crustaceans and aquatic plants in Texas waters. Texas Parks and Wildlife Department, Management Data Series 78, Austin, TX. 19 pp.

Idaho Fish and Game. 1990. Fisheries Management Plan 1991-1995. Appendix I: A list of Idaho fishes and their distribution by drainage. Idaho Fish and Game.

Jenkins, R. E., and N. M. Burkhead. 1994. Freshwater fishes of Virginia. American Fisheries Society, Bethesda, MD.

Jordan, D. S. 1882. Report on the fishes of Ohio. Report of the Geological Survey of Ohio 4(1):735-1002.

Linder, A. D. 1963. Idaho's alien fishes. Tebiwa 6(2):12-15.

Matern, S.A., P.B. Moyle, and L.C. Pierce. 2002. Native and alien fishes in a California estuarine marsh: twenty-one years of changing assemblages. Transactions of the American Fisheries Society. 131: 797-816.

Menhinick, E. F. 1991. The freshwater fishes of North Carolina. North Carolina Wildlife Resources Commission. 227 pp.

Morris, J., L. Morris, and L. Witt. 1974. The fishes of Nebraska. Nebraska Game and Parks Commission, Lincoln, NE. 98 pp.

Morse, S. R. 1905. Fresh and salt water fish found in the waters of New Jersey, part I. Annual Report of the New Jersey State Museum. MacCrellish and Quigley, State Province, Trenton, NJ.

Moyle, P. B. 1976a. Inland fishes of California. 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.

Popov, B. H., and J. B. Low. 1953. Game, fur animal, and fish introductions into Utah. Utah State Department of Fish and Game Publication 4, pp. 1-85.

Sanderson, B.L., K.A. Barnas, and A.M.W. Rub. 2009. Nonindigenous species of the Pacific northwest: an overlooked risk to endangered salmon? BioScience 59(3): 245-256.

Shields, B.A., P. Bird, W.J. Liss, K.L. Groves, R. Olson, and P.A. Rossignol. 2002. The nematode Anisakis simplex in American shad (Alosa sapidissima) in two Oregon Rivers. The Journal of Parasitology 88(5): 1033-1035.

Sigler, F. F., and R. R. Miller. 1963. Fishes of Utah. Utah Department of Fish and Game, Salt Lake City, UT. 203 pp.

Simpson, J., and R. Wallace. 1978. Fishes of Idaho. University of Idaho Press, Moscow, ID.

Skinner, J. E. 1962. An historical overview of the fish and wildlife resources of the San Francisco Bay area. California Fish and Game Water Projects Branch Report. 1:225 pp.

Smith, C. L. 1985. The inland fishes of New York state. New York State Department of Environmental Conservation, Albany, NY. 522 pp.

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. Bulletin of the U.S. Fish Commission 15: 379-472.

Sommer, T, B. Harrell, M. Nobriga, R. Brown, P. Moyle, W. Kimmerer, and L. Schemel. 2001. California's Yolo Bypass: Evidence that flood control can be compatible with fisheries, wetlands, wildlife, and agriculture. Fisheries. American Fisheries Society. 26 (8): 6-16.

Tilmant, J.T. 1999. Management of nonindigenous aquatic fish in the U.S. National Park System. National Park Service. 50 pp.

Trautman, M. B. 1981. The fishes of Ohio. Ohio State University Press, Columbus, OH.

Wiltzius, W. J. 1985. Fish culture and stocking in Colorado, 1872-1978. Division Report 12. Colorado Division of Wildlife.

Wydoski, R.S., and R.R. Whitney. 1979. Inland fishes of Washington. University of Washington Press, Seattle, WA.

Other Resources:
FishBase Summary

Author: Pam Fuller, and Matt Neilson

Revision Date: 11/4/2013

Peer Review Date: 11/4/2013

Citation Information:
Pam Fuller, and Matt Neilson, 2024, Alosa sapidissima (Wilson, 1811): U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=491, Revision Date: 11/4/2013, Peer Review Date: 11/4/2013, 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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