Common name: Alligator Gar

Taxonomy: available through www.itis.gov

Identification: Suttkus (1963); Page and Burr (1991); Etnier and Starnes (1993). Synonym Lepisosteus spatula.

Size: 3 m.

Native Range: Mississippi River basin from southwestern Ohio and southern Illinois south to Gulf of America; Gulf Coastal Plain from Econfina River, Florida, to Veracruz, Mexico (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: The Alligator Gar lives in coastal estuaries and major coastal rivers (Mettee et al. 1996). It is found in fresh, brackish, and occasionally salt water (Boschung and Mayden, 2004). The Alligator Gar is the largest of the gars, reaching nearly 10 feet in length (Ross, 2001). It feeds primarily on fishes, but will also eat crabs, carrion, and birds. This species spawns in late spring; the eggs are toxic (Ross, 2001).

Means of Introduction: The introduction of the California individual was attributed to release by an aquarium hobbyist (Raquel 1992). It is probably that the South Carolina specimen was also an aquarium release.  This species is becoming fairly common in the aquarium trade (P. Fuller, pers. observation).

Status: Reported in California and South Carolina.

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: The California specimen was recorded in water with a temperature of 25°C and a salinity of approximately 4.5 ppt (Raquel 1992).

References: (click for full references)

Boschung, H.T., Jr. and R.L. Mayden. 2004. Fishes of Alabama. Smithsonian Books, Washington. 736 pp.

Etnier, D.A. and W.C. Starnes. 1993. The Fishes of Tennessee. The University of Tennessee Press, Knoxville, TN. 681 pp.

Mettee, M.F., P.E. O'Neil, and J.M. Pierson. 1996. Fishes of Alabama and the Mobile Basin. Oxmoor House, Inc, Birmingham, AL. 820 pp.

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.

Raquel, P. F. 1992. Record of the alligator gar (Lepisosteus spatula) from the Sacramento-San Joaquin Delta. California Fish and Game 78(4):169-171.

Ross, S. 2001. The Inland Fishes of Mississippi. University Press of Mississippi. Jackson, Mississippi.

Suttkus, R.D. 1963. Order Lepisostei in: Bigelow et al. (eds.) Fishes of the Western North Atlantis. Soft-rayed Bony Fishes, Vol. 1, pt. 3, Memoir. Sears Foundation of Marine Research, Yale University, New Haven, Connecticut. pp 61-88.

Other Resources:
Photo of 6'9"; 194 lb fish

Photo courtesy of California Academy of Sciences

US Fish and Wildlife Service Ecological Risk Screening Summary for Atractosteus spatula

Author: Fuller, P.

Peer Review Date: 8/7/2013

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.