Map of gray wolf and red wolf current and historic range and suitable habitat across the U.S. and Mexico. Produced by Defenders of Wildlife (2021). All data sources listed below:Gray Wolf:Historic Range: The historic range for the gray wolf was delineated with the help of peer reviewed sources: Rutledge et al. 2010. Genetic and morphometric analysis of sixteenth century Canis skull fragments: implications for historic eastern and gray wolf distribution in North America.Current Range: Range delineation was based on range data from IUCN and USFWS, expert knowledge, and personal communications from Defenders of Wildlife field teams, academia, and federal agencies. Details of delineations focused mostly on the United States and Mexico as ranges north of that couldn’t be confirmed due to controversies.Suitable Habitat:Bennett, L.E. 1994. Colorado Gray Wolf Recovery: A biological feasibility study. Final Report. U.S. Fish and Wildlife Service and University of Wyoming Fish and Wildlife Cooperative research unit, Laramie, Wyoming, USA. Available at: https://babel.hathitrust.org/cgi/pt?id=umn.31951p00672031a;view=1up;seq=146California Department of Fish and Wildlife. 2016b. Potential Suitable Habitat in California. Pages 153-160 in Conservation Plan for Gray Wolves in California Part 2. Carroll, C., Phillips, M.K., Lopez-Gonzalez, C.A., and Schumaker, N.H. 2006. Defining Recovery Goals and Strategies for Endangered Species: The Wolf as a Case Study. BioScience 56(1): 25–37, https://doi.org/10.1641/0006-3568(2006)056[0025:DRGASF]2.0.CO;2Carroll, C. 2003. Impacts of Landscape Change on Wolf Viability in the Northeastern U.S. and Southeastern Canada. Wildlands Project Special Paper No. 5, available at https://www.klamathconservation.org/docs/wolfviabilitypaper.pdf.Carroll, C. 2007. Application of habitat models to wolf recovery planning in Washington. Unpublished report.Defendersof Wildlife. 2006. Places for Wolves: A Blueprint for Restoration and Recovery in the Lower 48 StatesDefenders of Wildlife. 2013. Places for WolvesHarrison, D. J., and T. G. Chapin. 1998. An assessment of potential habitat for eastern timber wolves in the northeastern United States and connectivity with occupied habitat in southeastern Canada. Wildlife Conservation Society, Working Paper Number 7.Harrison, D. J., and T. G. Chapin. 1998. Extent and connectivity of habitat for wolves in eastern North America. Wildlife Society Bulletin 26: 767-775, available at https://wolfology1.tripod.com/id207.htmHearne D., Lewis K., Martin M., Mitton E., and Rocklen C. 2003. Assessing the Landscape: Toward a Viable Gray Wolf Population in Michigan and Wisconsin. Hendricks, S.A., Schweizer, R.M., Harrigan, R.J., Pollinger, J.P., Paquet, P.C., Darimont, C.T., Adams, J.R., Waits, L.P., vonHoldt, B.M., Hohenlohe1, P.A. and R.K. Wayne. 2018. Natural recolonization and admixture of wolves (Canis lupus) in the US Pacific Northwest: challenges for the protection and management of rare and endangered taxa. The Genetics Society. Heredity. https://doi.org/10.1038/s41437-018-0094-x.Jimenez, M.D. et al. 2017. Wolf Dispersal in the Rocky Mountains, Western United States: 1993–2008. The Journal of Wildlife Management 81(4):581–592.Larson, T. and W.J. Ripple. 2006. Modeling Gray Wolf (Canis lupus) habitat in the Pacific Northwest, U.S.A. Journal of Conservation Planning 2:17-33.Maletzke, B.T. and R.B. Wielgus. 2011. Development of wolf population models for RAMAS© analysis by the Washington Department of Fish and Wildlife.Martinez-Meyer E., Gonzalez-Bernal A., Velasco J.A., Swetnam T.L., Gonzalez-Saucedo Z.Y., Servin J., Lopez-Gonzalez C.A., Oakleaf, J.A., Liley S., and Heffelfinger J.R. 2020. Rangewide habitat suitability analysis for the Mexican wolf (Canis lupus baileyi) to identify recovery areas in its historical distribution. Diversity and Distributions 00:1-13.McNab, W.H., Cleland, D.T., Freeouf, J.A., Keys, Jr., J.E., Nowacki, G.J., Carpenter, C.A., comps. 2007. Description of ecological subregions: sections of the conterminous United States [CD-ROM]. Gen. Tech. Report WO-76B. Washington, DC: U.S. Department of Agriculture, Forest Service. 80 p.McNab, W.H. and P.E. Avers. 1995. Ecological subregions of the United States. Washington, DC: U.S. Department of Agriculture, Forest Service, available at https://www.fs.fed.us/land/pubs/ecoregions/.Mladenoff, D.J., Sickley, T.A., Haight, R.G. and Wydeven, A.P. 1995. A Regional Landscape Analysis and Prediction of Favorable Gray Wolf Habitat in the Northern Great Lakes RegionMladenoff, D.J. and T.A. Sickley. 1998. Assessing Potential Gray Wolf Restoration in the Northeastern United States: A Spatial Source. Journal of Wildlife Management 62(1): 1-10.Minnesota Dept. of Natural Resources. 2001. Minnesota Wolf Management Plan. Minnesota Dept. Natural Resources. 2017a. Gray Wolf, available at https://www.dnr.state.mn.us/mammals/wolves/mgmt.html.Montana Fish Wildlife & Parks. 2004. Montana Gray Wolf Conservation and Management Plan.Montana Fish,Wildlife & Parks. 2018. Montana Annual Report 2018: Wolf Conservation and Management.Oakleaf J.K., Murray D.L., Oakleaf J.R., Bangs E.E., Mack C.M., Smith D.W., Fontaine J.A., Jimenez M.D., Meier T.J., and C.C. Niemeyer. 2006. Habitat Selection by Recolonizing Wolves in the Northern Rocky Mountains of the United States. Journal of Wildlife Management 70(2):554-563.Oregon Department of Fish and Wildlife. 2015. Updated mapping potential gray wolf range in Oregon.Potvin M.J., Drummer T.D., Vucetich J.A., Beyer E. Jr., and J.H. Hammill. 2005. Monitoring and Habitat Analysis for Wolves in Upper Michigan. Journal of Wildlife Management 69(4):1660-1669.Treves A., Martin K.A., Wiedenhoeft J.E., Wydeven A.P. (2009) Dispersal of Gray Wolves in the Great Lakes Region. In: Wydeven A.P., Van Deelen T.R., Heske E.J. (eds) Recovery of Gray Wolves in the Great Lakes Region of the United States. Springer, New York, NY. https://doi.org/10.1007/978-0-387-85952-1_12USGS Gap Analysis Project Species Range and Predicted Habitat: Gray wolf: https://gapanalysis.usgs.gov/apps/species-data-download/Washington Dept. of Fish and Wildlife (WDFW). 2017. Washington Gray Wolf Conservation and Management 2017 Annual Report.Wiles, G. J., H. L. Allen, and G. E. Hayes. 2011. Wolf conservation and management plan for Washington. Washington Department of Fish and Wildlife, Olympia, Washington. 297 pp.Red Wolf:Historic Range:Red wolf historic range established by USFWS based on information provided by the 2016 Wildlife Management Institute report [ Wildlife Management Institute: A Review and Evaluation of the Red Wolf (Canis rufus) Historic Range, Final Report – 5/25/2016]. The historic range layer is a combination of the following Level II EPA Ecoregions: 1) Mississippi Alluvial and Southeast USA Coastal Plains, 2) Ozark/Ouachita-Appalachian Forests, 3) South Central Semi-Arid Prairies, 4) Southeastern USA Plains, and 5) Texas-Louisiana Coastal PlainsCurrent Range (Recovery Area):Red wolf recovery area adapted from the USFWS current range information.Suitable Habitat:Toivonen L.K. (2018) Assessing red wolf conservation based on analyses of habitat suitability and human perception of carnivores.Karlin M., Vaclavik T., Chadwick J., and R. Meentemeyer. (2016) Habitat use by adult red wolves, Canis rufus, in an agricultural landscape, North Carolina, USA. Mammal Study 41:87-95.