Rediscovery of remnant wild red wolves and ghost alleles in Gulf Coast canids

Rediscovering species once thought to be extinct or on the edge of extinction is rare. Globally, human activity in nearly every habitat type has resulted in a vanishing number of environments in which organisms can remain undetected. In the era of genomics, we now have the power to discover the remnants of extinct genomes as ghost alleles that persist cryptically on the landscape in admixed individuals. The power to detect remnant genomes of extinct or declining species brings with it new opportunities for biodiversity conservation during the current extinction crisis. Here, we report on the rediscovery of red wolf alleles in canids on an island along the Gulf Coast of Texas where red wolves were believed to be extinct since 1980. With a reduced representation genomics approach, we analyzed over 6,000 SNPs in 62 canids, including representatives from all legally recognized North American Canis species, as well as two phenotypically ambiguous canids originating from Galveston Island, Texas. We report a notably high level of genetic similarity among these Galveston samples and captive red wolves. Today, the only known extant wild red wolves persist in a reintroduced population in North Carolina which is dwindling amongst political and scientific controversy. Our rediscovery of red wolf ancestry after almost 40 years introduces both positive opportunities for additional conservation action and difficult policy challenges.