A gray wolf that was shot by a hunter in Utah was the same one spotted in the Grand Canyon area last year, federal wildlife officials said Wednesday.

The 3-year-old female wolf — named “Echo” in a nationwide student contest — captured the attention of wildlife advocates across the county because it was the first wolf seen in the Grand Canyon in 70 years.

The U.S. Fish and Wildlife Service did DNA tests to confirm the wolf killed in late December by a Utah hunter who said he thought he was shooting a coyote was the same one that was seen roaming the Grand Canyon’s North Rim and nearby forest in October and November, said agency spokesman Steve Segin.

Geneticists at the University of Idaho compared DNA taken from the northern gray wolf killed in southwestern Utah with scat samples taken from the wolf seen near the Grand Canyon last fall.

The hunter who killed the wolf called Utah state officials in December and said he mistook the wolf for a coyote, said Utah Division of Wildlife Resources spokesman Mark Hadley. The man, whose name was not released, said he didn’t realize his mistake until he came up on the dead animal. In Utah, anybody can hunt coyotes.

The state handed over its initial findings of what happened to U.S. Fish and Wildlife, Hadley said. That investigation is ongoing and could take weeks or months to complete, Segin said. It’s not clear yet what penalties the hunter could face for killing the animal.

Wolves are protected in Utah under the Endangered Species Act.

Wildlife advocacy groups have called the wolf’s death heartbreaking and say they want the hunter prosecuted. They said the animal could have helped wolves naturally recover in remote regions of Utah and neighboring states.

“Wolves and coyotes are distinguishable if one pauses for a second before pulling a trigger,” said Michael Robinson with the Center for Biological Diversity. “There are consequences for pulling the trigger when you don’t know what you’re aiming at. It’s important to have justice for this animal.”

Wolves and coyotes often have similar coloring, but wolves are usually twice as large as coyotes, said Kim Hersey, mammal conservation coordinator with Utah Division of Wildlife Resources. Wolves also have longer legs, bigger feet and rounder ears and snouts, she said.

But, Hersey says how well a person could distinguish between the two would depend on the lighting, the distance and how much experience a hunter has comparing the two animals.

The wolf had worn a radio collar since January 2014.

Wolves can travel thousands of miles for food and mates. Gray wolves had been spotted as far south as Colorado until the Arizona wolf was confirmed. Gray wolves last were seen in the Grand Canyon area in the 1940s.

In recent years, the Fish and Wildlife Service lifted protections for the wolves in the Northern Rockies and western Great Lakes. But a federal judge recently reinstated the protections after wildlife advocates in Wyoming sued.

The Center for Biological Diversity has documented 11 cases since 1981 where hunters told wildlife officials they had shot a wolf thinking it was a coyote.