Two days ago, he was a glimmer of hope.
Firefighter Michael Herdman's dog, Duke, was spotted Wednesday wandering the canyon not far from where he went missing.
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Now, search teams are more determined than ever to catch that dog.
On Friday, a special team from the city of Los Angeles joined the mission to find Herdman in the Los Padres National Forest after the firefighter from Arcadia disappeared on June 13.
They are uniquely trained animal control officers who will be using a baited trap to lure the German short-hair into custody.
When searchers first spotted Duke a couple of days ago, they had hoped he could lead them back to the missing firefighter, who had wandered into the wilderness last Friday to chase him.
But that theory appears to have played itself out now. And the mission is to get the dog to safety.
"That’s our concern at this point, is the food intake isn’t gonna be there for him so we need to move fast to try to capture him," an official said.
The team that departed via helicopter is prepared to stay overnight in the remote canyon, in order to keep the dog safe from predators.
Sgt. Eric Buschow, with the Ventura County Sheriff's Department, said the goal is to lure and trap Herdman's dog.
The caged trap will include Duke's bed from home as well as some blankets and toys that were brought from home and the dog's owner's clothing, officials said.
Herdman's hiking partner and friend says he had run into the wilderness wearing just shorts and a T-shirt.
There is water in the canyon, but no food. And with each passing day, there's growing concern that he may be seriously injured or worse.
People have died here in the past.
Searchers are out in this back country every year searching for lost hikers, Buschow said.
Teams are wading through creek water, climbing giant boulders. Some have been injured. A snake bite and a leg injury are among the worst. One of them contracted a serious rash after being exposed to poison oak.
Two other search and rescue people were treated for heat exhaustion.
In 1969, six boys never got out alive after a camping trip. Locals and NBC4 viewers have relayed stories of other backpackers who were experienced and prepared, but couldn't survive the rugged canyons.
Some of them have never been found.