When the call came in Saturday evening, Cowlitz County deputies were dubious.

Several miles west of the Cowlitz River and sleepy downtown Castle Rock, a driver said they spotted a massive sea lion walking down the middle of a rural road.

Dispatchers were disbelieving. “I’m sorry. A feline? No? A Sea lion?”

“It just doesn’t sound right,” Troy Brightbill, the chief criminal deputy at the sheriff’s office, said of the marine mammal sighting, reported about 8 p.m.

Eventually, law enforcement officers and wildlife officials confirmed it with their own eyes. An estimated 600- to 700-pound female Steller sea lion had indeed made its way into the hills from the river, traveling up various creeks and onto Garlock Road in a wooded area of the southwest Washington county.

Scott Schroeder, a wildlife officer with Washington’s Department of Fish and Wildlife, responded to a landscape he described as a “pretty, rolling, forested area.”

Steller sea lions are found along the northern Pacific Ocean but often travel up river systems. They go where the food is. Schroeder said he’s seen sea lions in a variety of places, even 30 or more miles upriver on the Cowlitz, but never in this setting.

“There’s no other way to say it,” Schroeder said of sea lions and seals when you spot them in the river. “They’re fairly cute animals.”

But in the middle of the night, on a dark forest road, the cuteness fades as the teeth bare. The barks are no longer cute. San Francisco’s Pier 39 this isn’t.

“She was very aggressive,” Schroeder said. “If you got within 20 feet of her, she would go after you.”

Brightbill, with the sheriff’s office, said deputies saw the speed and aggression firsthand. “As we’ve learned, they’re fairly mobile on land,” he said.

Schroeder said the sea lion would turn on its flippers and lunge “like an alligator” at anyone who got too close.

“She was certainly full of spit and vinegar,” he said.

Despite that, people couldn’t help but take videos and photos. Sgt. Corey Huffine snapped a bleary-eyed sea lion selfie. A majestic photo posted by the sheriff’s office shows the pottering pinniped appearing to take in the grandeur of the forest setting.

Schroeder, the wildlife official said, the animal appeared to be healthy and had her wits about her.

Through Saturday night and into Sunday morning, deputies and other state officials checked in with the animal periodically. Schroeder said he was hoping she would return to the creek and work her way back to the Cowlitz river on her own.

That didn’t happen.

Brightbill said for a while the sea lion had a single deputy serving as its personal minder – focused on preventing a collision with a car. “The problem was it just kept moving,” he said.

Because of the location, time and limited weekend staffing, wildlife officers thought it best to leave her overnight. But about 1 a.m., more calls came in. She was more than 2 miles from a viable water source and was in the middle of the road.

At various points Sunday, as many as 15 people were on scene, especially at the end, when crews from the county public works office, humane society, state wildlife department and sheriff’s office joined forces to corral the mammal.

“I think everybody had a face full of sea lion breath more than once,” Schroeder said.

Sea lions, both Steller and their cousins, California, are increasingly abundant in the lower Columbia River and its tributaries. Schroeder said the marine mammals are feasting on a smelt run in the river system at the moment. He estimated there were hundreds of sea lions in the Cowlitz River alone.

Their presence in the Columbia, Willamette and other major rivers in recent years spawned federal legislation as Oregon and Washington succeeded in pushing for lenience to kill more of the mammals to protect endangered fish.

Eventually on Sunday, the situation had improved significantly, safety-wise. Instead of being in the middle of the road, the sea lion was in someone’s driveway. Crews responded with a trailer and cage and were able to successfully guide the animal into the cage by holding large sheets of plywood and directing her that way.

“I’m actually surprised that it worked that well,” Schroeder said.

With that, the crews drove the animal back to the Willow Grove boat ramp in Longview, about 14 miles west. At 4:18 p.m., crews dumped the sea lion into the Columbia.

She was off into a different river, after first being given a clean bill of health. Schroeder theorized that the marine mammal may have looked for clearer waters in the tributaries of the Cowlitz, given that the main river currently is clouded with debris and sediment.

Schroeder is surprised by one thing. Given how many of the massive mammals are out in the rivers, he said he’s surprised something like this doesn’t happen more often.

-- Andrew Theen; atheen@oregonian.com; 503-294-4026; @andrewtheen

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