Page Banner

United States Department of Agriculture

Agricultural Research Service

Potential United States Range Expansion of the Invasive Fire Ant
headline bar
U.S. Map

 

State Maps (click on a name at the right to view the state map):

Potential red imported fire ant range expansion

Range expansion legendThis map predicts areas in the United States that are susceptible to invasion by the red imported fire ant, Solenopsis invicta. Predictions are based on climate and current northernmost distributions of red imported fire ants. To generate these predictions, a dynamic model of colony growth was developed which depended on daily maximum and minimum soil temperatures. Temperature records at 4,537 meteorological stations within the current and potential range of S. invicta were obtained from NOAA's National Climatic Data Center. At each station, a colony was allowed to grow and reproduce. The map of reproducing colonies was then compared with the current fire ant distribution. After calibration to the current northernmost extremes in Arkansas, Tennessee, and Oklahoma, four zones of colony success were defined: certain, possible, undemonstrated, and improbable. An annual precipitation limit was selected to indicate regions where arid conditions may prohibit growth in non-irrigated areas. Results of the model predict that red imported fire ants will likely move 50-100 miles north in Oklahoma and Arkansas. They will also likely continue expanding into portions of Virginia, Maryland, and Delaware in the east and New Mexico, Arizona, California, Oregon, Nevada, and maybe even Washington and Utah in the west.

This study was a joint project of the University of Arkansas at Monticello and the USDA-ARS lab here in Gainesville, Florida. For more information see:

Korzukhin, M. D., S. D. Porter, L. C. Thompson, and S. Wiley. 2001. Modeling Temperature-Dependent Range Limits for the Red Imported Fire Ant (Hymenoptera: Formicidae: Solenopsis invicta) in the United States. Environ. Entomol. 30: 645-655.  Adobe formatted document

The Hawaiian map was provided by M. Korzukhin and E.VanGelder, USGS/BRD, Haleakala Field Station, Makawao, Hawaii.

 


Arizona

Arizona distribution

Map legendPotential distribution of red imported fire ants in the general landscape. Please note that "certain" and "possible" sites with insufficient rainfall are still at risk along natural waterways and in areas that are irrigated. Limited numbers of red imported fire ants may also be able to survive in colder climates in the "Undetermined" or even "Improbable" infestation zones in urban environments and other areas with artificial heat sources. This species may also be able to temporarily expand its range into colder regions during unusually warm years.


Arkansas

Arkansas distribution

Map legendPotential distribution of red imported fire ants in the general landscape. Please note that "certain" and "possible" sites with insufficient rainfall are still at risk along natural waterways and in areas that are irrigated. Limited numbers of red imported fire ants may also be able to survive in colder climates in the "Undetermined" or even "Improbable" infestation zones in urban environments and other areas with artificial heat sources. This species may also be able to temporarily expand its range into colder regions during unusually warm years.


California

California distribution

Map legendPotential distribution of red imported fire ants in the general landscape. Please note that "certain" and "possible" sites with insufficient rainfall are still at risk along natural waterways and in areas that are irrigated. Limited numbers of red imported fire ants may also be able to survive in colder climates in the "Undetermined" or even "Improbable" infestation zones in urban environments and other areas with artificial heat sources. This species may also be able to temporarily expand its range into colder regions during unusually warm years.


Hawaii

Hawaii distribution

Potential distribution of red imported fire ants in the general landscape. Please note that "certain" and "possible" sites with insufficient rainfall are still at risk along natural waterways and in areas that are irrigated. Limited numbers of red imported fire ants may also be able to survive in colder climates in the "Undetermined" or even "Improbable" infestation zones in urban environments and other areas with artificial heat sources. This species may also be able to temporarily expand its range into colder regions during unusually warm years.


Maryland

Maryland distribution

Map legendPotential distribution of red imported fire ants in the general landscape. Please note that "certain" and "possible" sites with insufficient rainfall are still at risk along natural waterways and in areas that are irrigated. Limited numbers of red imported fire ants may also be able to survive in colder climates in the "Undetermined" or even "Improbable" infestation zones in urban environments and other areas with artificial heat sources. This species may also be able to temporarily expand its range into colder regions during unusually warm years.


Nevada

Nevada distribution

Map legendPotential distribution of red imported fire ants in the general landscape. Please note that "certain" and "possible" sites with insufficient rainfall are still at risk along natural waterways and in areas that are irrigated. Limited numbers of red imported fire ants may also be able to survive in colder climates in the "Undetermined" or even "Improbable" infestation zones in urban environments and other areas with artificial heat sources. This species may also be able to temporarily expand its range into colder regions during unusually warm years.


New Mexico

New Mexico distribution

Map legendPotential distribution of red imported fire ants in the general landscape. Please note that "certain" and "possible" sites with insufficient rainfall are still at risk along natural waterways and in areas that are irrigated. Limited numbers of red imported fire ants may also be able to survive in colder climates in the "Undetermined" or even "Improbable" infestation zones in urban environments and other areas with artificial heat sources. This species may also be able to temporarily expand its range into colder regions during unusually warm years.


North Carolina

North Carolina distribution

Map legendPotential distribution of red imported fire ants in the general landscape. Please note that "certain" and "possible" sites with insufficient rainfall are still at risk along natural waterways and in areas that are irrigated. Limited numbers of red imported fire ants may also be able to survive in colder climates in the "Undetermined" or even "Improbable" infestation zones in urban environments and other areas with artificial heat sources. This species may also be able to temporarily expand its range into colder regions during unusually warm years.


Oklahoma

Oklahoma distribution

Map legendPotential distribution of red imported fire ants in the general landscape. Please note that "certain" and "possible" sites with insufficient rainfall are still at risk along natural waterways and in areas that are irrigated. Limited numbers of red imported fire ants may also be able to survive in colder climates in the "Undetermined" or even "Improbable" infestation zones in urban environments and other areas with artificial heat sources. This species may also be able to temporarily expand its range into colder regions during unusually warm years.


Oregon

Oregon distribution

Map legendPotential distribution of red imported fire ants in the general landscape. Please note that "certain" and "possible" sites with insufficient rainfall are still at risk along natural waterways and in areas that are irrigated. Limited numbers of red imported fire ants may also be able to survive in colder climates in the "Undetermined" or even "Improbable" infestation zones in urban environments and other areas with artificial heat sources. This species may also be able to temporarily expand its range into colder regions during unusually warm years.


Tennessee

Tennessee distribution

Map legendPotential distribution of red imported fire ants in the general landscape. Please note that "certain" and "possible" sites with insufficient rainfall are still at risk along natural waterways and in areas that are irrigated. Limited numbers of red imported fire ants may also be able to survive in colder climates in the "Undetermined" or even "Improbable" infestation zones in urban environments and other areas with artificial heat sources. This species may also be able to temporarily expand its range into colder regions during unusually warm years.


Texas

Texas distribution

Map legendPotential distribution of red imported fire ants in the general landscape. Please note that "certain" and "possible" sites with insufficient rainfall are still at risk along natural waterways and in areas that are irrigated. Limited numbers of red imported fire ants may also be able to survive in colder climates in the "Undetermined" or even "Improbable" infestation zones in urban environments and other areas with artificial heat sources. This species may also be able to temporarily expand its range into colder regions during unusually warm years.


Virginia

Virginia distribution

Map legendPotential distribution of red imported fire ants in the general landscape. Please note that "certain" and "possible" sites with insufficient rainfall are still at risk along natural waterways and in areas that are irrigated. Limited numbers of red imported fire ants may also be able to survive in colder climates in the "Undetermined" or even "Improbable" infestation zones in urban environments and other areas with artificial heat sources. This species may also be able to temporarily expand its range into colder regions during unusually warm years.


Washington

Washington distribution

Map legendPotential distribution of red imported fire ants in the general landscape. Please note that "certain" and "possible" sites with insufficient rainfall are still at risk along natural waterways and in areas that are irrigated. Limited numbers of red imported fire ants may also be able to survive in colder climates in the "Undetermined" or even "Improbable" infestation zones in urban environments and other areas with artificial heat sources. This species may also be able to temporarily expand its range into colder regions during unusually warm years.


Last Modified: 5/10/2006