An endangered wolf travelled thousands of miles across the US in search of a mate but died before it could find one, officials tracking the canine’s movements have said.

The female grey wolf was first captured in October 2017 by biologists in Oregon who began tracking the endangered animal’s movements. The young canine, named OR-54, was found dead on Wednesday in California.

The wolf had been searching for a mate, or another pack, officials said, and wandered at least 8,712 miles in its hunt. It’s not yet known how the animal died, but state officials say they have launched an investigation. The shooting death of another collared wolf – OR-59 – is unsolved, and the US Fish and Wildlife Service announced a $2,500 (£1,940) reward in January for information on that case.

Researchers say OR-54 was three or four when it died. Its tagging in 2017 was a happy find. “At long last!”, the Oregon Fish and Wildlife Office wrote on Facebook.

State and federal wildlife officials had long been trying to collar a wolf from Oregon’s so-called Rogue Pack. The tracking collar on wolf OR-7, the founding member of that pack, had stopped working years prior, and officials had not been able to place a new tracking device on any of the protected animals in the area for several years.

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Then they snagged OR-54, the 54th wolf collared in that state, and OR-7′s daughter.

The Oregon-born OR-7 was the first wild grey wolf documented in California since the species was widely eradicated in the 20th century. Its presence helped establish state protections for grey wolves. It travelled widely before returning to Oregon, finding a mate and starting the Rogue Pack.

In 2018, OR-54 followed its father’s pawsteps to the Golden State.

It crossed from Oregon into California on 24 January, 2018, and mostly stayed, first traversing eastern Siskiyou County before walking through Butte, Lassen, Modoc, Nevada, Plumas, Shasta, Sierra and Tehama counties in search of a mate, according to the Sacramento Bee. It twice returned to Oregon. It briefly sneaked into Nevada. It travelled an average of 13 miles a day – a lengthy journey that seemed to cover a lot of the same ground its father crossed years before.

Amaroq Weiss, a wolf advocate at the Centre for Biological Diversity, said in a news release that like its father: “OR-54 was a beacon of hope who showed that wolves can return and flourish here.”

She told The Washington Post the wolf’s death sets back the “trajectory we hoped for wolf recovery”.

“Being a wolf in the wild is very fragile,” Ms Weiss said. “It’s surprising to most. But a lone wolf usually doesn’t live past 4 or 5 years.”

She said lone wolves may be killed by wolf packs, kicked by the elk they’re chasing or killed by humans.

Except for a few run-ins, OR-54’s journey appeared mostly solitary.

“I think the fact that she travelled so far if nothing else is an indication that we don’t have a lot of lone wolves for her to have met up with,” Ms Weiss said.

Fewer than a dozen known wolves live in California. In July, tracking devices found that OR-54 crept towards the territory of the only known wolf pack in the state, according to the Sacramento Bee. But she didn’t stay for long. She was also suspected in at least five livestock attacks.

Wolves have long been despised by ranchers and farmers, an industry whose influence wildlife advocates in part blame for reluctance at the state and federal level to develop recovery plans for the controversial predators.

Last March, the Trump administration proposed stripping federal protections for grey wolves in the US, saying the species had successfully recovered. Still, some states are taking wolf recovery efforts into their own hands: In Colorado, for example, voters will decide via a ballot measure in November whether to reintroduce the endangered species.

Ms Weiss said the loss of numerous wolves underlines “how important it is that we have protections in place for wolves”.

“We’d never have wolves coming back to California, coming to Oregon, if they hadn’t been listed for federal protections,” she said. She added: “We hope every wolf has a long flourishing life in which they can live out their own intrinsic existence, and at the same time contribute to a successful recovery of this species.”