Pack of Wild Dogs in Texas Carry DNA of Nearly Extinct Red Wolf

Red wolves once roamed a broad stretch of the southeastern United States, settling in several states including Texas, Florida and West Virginia. But by 1980, the canines were virtually extinct in the wild, their population largely limited to wolves born through captive breeding programs.

Today, just 40 or so of these elusive red wolves—stemming from a group reintroduced to North Carolina in the late ‘80s—remain living in the wild. Luckily, Ed Cara writes for Gizmodo, a team of Princeton University researchers recently chanced upon a surprising discovery that could very well secure the threatened species’ future: As the scientists report in the journal Genes, a pack of canines native to Texas’ Galveston Island carry elements of the red wolf’s DNA, including so-called “ghost alleles” once thought to have vanished from the genetic record.

Ron Wooten, a field biologist and photographer in Galveston, brought the wild dogs to the Princeton team’s attention after observing subtle differences between their appearance and that of Galveston’s dominant coyote population. Such purported red wolf sightings are common, but usually the animal in question is just a misidentified coyote. However, Wooten’s alert “stood out,” notes study co-author Bridgett vonHoldt, an ecologist and evolutionary biologist at Princeton.

“His enthusiasm and dedication struck me, along with some very intriguing photographs of the canines,” she explains in a statement. “They looked particularly interesting and I felt it was worth a second look.”

Wooten sent the researchers two samples drawn from pack members killed by cars. After extracting DNA from the roadkill, the team compared it to genomes from an array of related species, including 29 coyotes, 10 gray wolves, 10 eastern wolves and 11 red wolves bred in captivity.

According to Amanda Hollenbeck of Laboratory Equipment, the DNA analysis revealed shared genes found only in red wolf populations, as well as genetic variations unseen in any other canines tested. It’s possible that these anomalous genes are ghost alleles lost during captive breeding. Overall, the tests suggest the Galveston dogs are a hybrid of red wolf and coyote, but further testing is needed to confirm this assessment, Princeton biologist and study lead author Elizabeth Heppenheimer tells the Associated Press’ David Warren.

Red wolves—better known in scientific circles as Canis rufus—are medium-sized canines whose 45- to 80-pound weight places them somewhere between the coyote and the gray wolf. As the creature’s name indicates, its fur features a reddish tint most noticeable on the ears, head and legs.

Thanks to human hunting, habitat loss and interspecies breeding, the red wolf landed on the endangered species list in 1967. As the U.S. Fish and Wildlife Service’s website states, captive breeding programs launched soon after; in 1980, the last known wild red wolves were moved to human-overseen facilities, leading scientists to deem the species biologically extinct in the wild.

At the height of captive breeding efforts, researchers boasted a population of some 240 canines. Due to interbreeding with coyotes, however, only 17 were pure red wolf. Of these 17, a total of 14 successfully reproduced, enabling the reintroduction of red wolves to North Carolina during the late 1980s.

According to the AP’s Warren, this North Carolina population peaked at between 120 to 130 wolves in 2006. Now, only 40 or so remain in the wild. An additional 200 live in zoos and wildlife facilities across the country.

The most significant implications of the team’s findings revolve around future conservation efforts. As Cara notes for Gizmodo, careful breeding between the wild Galveston canines and remaining red wolves could “restore lost aspects of the species’ genetic history and keep them healthy.”

If red wolves are reintroduced to the Galveston area, it’s also possible that they could breed with local coyotes, sparking hybridization events that would restore red wolf genes lost in the captive breeding programs.

“Hybridization is relatively common in natural systems and does not always have negative consequences,” Heppenheimer tells the AP. Still, contemporary conservation policy remains prejudiced against hybridization, which is often seen as a deterrence to an endangered species’ survival.

As vonHoldt concludes in a statement, “Coyote populations may more likely represent a mosaic collection of individuals with diverse histories, with some possibly carrying the remnants of an extinct species. We hope that these findings resonate with policymakers and managers, and influence how we think about endangered genetics.”

Meilan Solly | | READ MORE

Meilan Solly is Smithsonian magazine's associate digital editor, history.