Expert: Wildlife bridge may be answer to concerns about decline of mountain lions

FALLBROOK, Calif. - A leading wildlife expert believes it may be necessary to build a most unusual bridge to help mountain lions prosper in San Diego County.

From green bridges in Germany and Canada, to wildlife overpasses in Montana and Washington, animals are trekking new paths across highways.

"I think a wildlife bridge and crossing should be looked at very seriously," said Winston Vickers, who works for UC Davis' Wildlife Health Center.

Vickers, a wildlife veterinarian, has been tracking mountain lions, or cougars, in the Santa Ana mountains, which extends into northern San Diego County -- an area that includes Camp Pendleton and Fallbrook.

"Vehicle collisions are the number one cause of death of cougars in Southern California in our study," said Vickers.

He said more than 50 have been killed in the last 25 years, including one killed in 4S Ranch in 2011.

It now appears fewer and fewer cougars are trying to cross highways.

Since 2001, Vickers and his team at UC Davis have tagged nearly 80 mountain lions.

The last known safe crossing in the county was in 2010, just south of Fallbrook, when a tagged mountain lion crossed under Interstate 15 by walking along Gopher Canyon Road

Vickers said many mountain lions in the San Diego area are simply turning around when they meet a highway.

The result: a crisscross of highways and development has placed the cougars into smaller areas, leading to a lack of genetic mixing, which could translate into problems in reproduction and immune systems, according to Vickers.

"There is a real concern there could be a decline in the population," said Vickers.

It's a concern that could be addressed with a wildlife bridge or underpass filled with native plants to blend in.

Vicker is planning an expert panel to determine how many bridges would be needed for mountain lions roam far and wide, safely.

How much would one cost? A large wildlife bridge built in Elko, Nev., cost $1.8 million.

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