LIHU'E, Kaua'i — Trained trackers from the Mainland yesterday began searching the cliffs at the back of Kalalau Valley for an Oregon man missing for almost a month, after finding evidence that someone started into the valley from the treacherous Pihea Trail.

Daniel Marks, 24, of Portland, arrived on Kaua'i Nov. 9 for what was to be a one-week trip. He was last seen Nov. 10, when he told someone he met that he intended to climb into Kalalau Valley from the Koke'e region.

There is no evidence that he made it into the valley, and as of late yesterday the trackers had not found him.

"He is most likely stuck or hurt or something up on the valley wall," said his sister, Susan Marks, who came to Kaua'i with her brother, Ron, to help guide a search effort.

There is no trail into Kalalau Valley from Koke'e, although Hawaiians had a route that was used into the 1800s. The back of the valley is more than 4,000 feet high and drops steeply for 2,500 feet before leveling off into a sloping floor.

On numerous occasions over the past decades, Kaua'i Fire Department crews have rescued hikers who have tried to find a way down on the trail and become stranded, or worse.

"We haven't had many recently, fortunately," said Wayne Souza, Kaua'i chief of the Division of State Parks, which oversees Kalalau Valley.

Police Lt. John Takamura said a woman reported picking up Marks, who was hitchhiking at the airport, and taking him to Kapa'a on Nov. 9.

Another sighting was reported by a man who said he drove Marks to the base of Waimea Canyon Drive, which leads to Koke'e.

The witnesses said Marks suggested he was interested in hiking along the Na Pali Coast and that he intended to try to hike into Kalalau.

Local search teams have combed the valley floor, but none of the campers and hikers they talked to said they had seen Marks, and there was no sign that he spent any time in the valley.

Susan and Ron Marks arranged for three members of Joel Hardin Professional Tracking Services of Everson, Wash., to try to find the route Marks may have taken. The trackers are volunteers taking time off their regular jobs, with the missing man's family paying their expenses.

Tracking instructor Bob Brady of Lake Stevens, Wash., said the agency's trackers are regularly called in to assist in searches, even after weeks have passed since the subjects went missing.

"You can track a person for a month or more after they're lost," he said.

In the clay near the Pihea Trail, which runs along the back rim of the valley, the trackers on Saturday found a boot track that looks like one Marks might have made, his sister said.

"It was consistent with his shoes," Susan Marks said. "It appears that he scouted out a place that was do-able," although she conceded the location may not have been any known route and may not have led to the valley bottom.

Daniel Marks is 5 feet 8 and weighs about 135 pounds. He has tattoos, including some faint markings above his temples. He has shoulder-length brown hair and was growing a beard. He regularly hikes alone, she said.

"It's not unusual for him to do this stuff," Susan Marks said.

Reach Jan TenBruggencate at jant@honoluluadvertiser.com.