Relocated Mountain Lions Starved to Death Attempting To Head Back Home

Two male cougars that were relocated from their home in the eastern Sierra Nevada to the Mojave Desert died of starvation as they tried to return home.

The two mountain lions—named L147 and L176—were moved some 200 miles by the California Department of Fish and Wildlife in 2021.

However, the lions attempted to walk back to their original homes, possibly to their mates, and tragically did not survive the journey.

As revealed in the California Department of Fish and Wildlife (CDFW) 2021 annual report on the Sierra Nevada Bighorn Sheep Recovery Program, L147 was found "in an emaciated condition suggesting starvation as a cause of mortality" on March 29, 2021, while L176 was discovered near to death, and "had to be euthanized" on May 12.

"Both L147 and L176 used separate underpasses to cross I-15, demonstrating the importance of wildlife crossing corridors on major highways," the report said.

The report stated that the pair's relocation was an experiment to see if the animals would cross the I-15 to return home. The Los Angeles Times reported, however, that this was inaccurate and that a new 2021-22 bighorn sheep report clarified that they were actually moved as an alternative to euthanization.

Mountain lions are a predator of bighorn sheep, a threatened species in the Sierra Nevada: only 125 of the sheep were living in the area as of the 1990s. This spurred conservation efforts, which have restored the population to 316 in 2016, and 277 as of 2022.

"At the time, CDFW was exploring alternatives to killing lions right there on the spot," Jordan Traverso, a CDFW spokesperson, told SFGate. "We regret that these lions died in this manner, and we will learn from it. As the report says, future translocations will benefit from many lessons learned in these cases."

Wildlife advocates were not pleased by the news of the cougar's deaths.

"Mountain lions are territorial creatures, intricately attuned to their surroundings," Zara McDonald, a biologist with the Bay Area Puma Project, told SFGate. "Relocation can induce immense stress and disorientation, leading to reduced survival rates (such as what occurred with the two recent males), limited hunting success, and higher susceptibility to disease due to unfamiliar environments."

The CDFW does not plan to relocate lions like this in the future, however.

"In hindsight, it wasn't a good place to release those lions," Tom Stephenson, a senior environmental scientist at the California Department of Fish and Wildlife, told the LA Times, adding, "and we're not moving them to that environment anymore."

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