ANCHORAGE, Alaska — The YouTube video making the rounds among Alaska surfers this week opens with a GoPro view of a guy paddling his board up Turnagain Arm. Soon a foamy bore-tide wave appears behind him. The wave hits. As it pushes him from behind, he tries to stand up. Then another surfer appears. That surfer is standing on his board, weaving in and out of the left side of the shot.

The surfer with the GoPro and the standing surfer exchange words and obscene gestures.

Then the board belonging to the standing surfer shoots across the wave, just missing the GoPro surfer. The wave passes. The two surfers paddle toward one another, yelling.

The language is salty, but, basically, the surfer with the GoPro tells the other guy that they are out just to have a good time. The other guy, who might have shot his board at the GoPro guy on purpose, isn’t in the mood.

“I’m born here,” the other guy shouts. “It’s my – – – – -in’ wave. – – – you.”

“You own the wave?” asks the GoPro guy, sounding incredulous.

“Yeah,” says the other guy.

“The other guy” will for the purposes of this column be known as Angry Surfer. Nobody knows his name but he’s been seriously harshing the mellow vibe among the growing community of bore-tide riders in Turnagain Arm. Longtime surfers hope his attitude isn’t a sign of what’s to come as riding the tide becomes more popular.

Hostile, territorial surfer behavior known as “localism” is nothing new, particularly in places where beaches are crowded, like Hawaii or California, said Scott Dickerson, a Homer, Alaska, native who runs the online surf community,

The usual scenario is that a group of locals intimidate interlopers, he said. But in Turnagain Arm the last few weeks, the issue is one guy who seems to be threatening everyone he runs into. By all accounts, he’s a pretty good surfer. But he gets so unhinged that people who’ve crossed him suspect he is crazy or high. Some worry he might turn seriously violent.

Until now, localism has not been much of a problem in the Arm, where a growing tribe of wetsuit-clad surfers, paddleboarders and kayakers come regularly to catch a single wave — created by the changing tides —that can carry them for miles, he said. Maybe a dozen people regularly surf the tide, and dozens of others surf less frequently. Catching the bore tide on a paddleboard has also become popular, bringing out more people than ever before. Regulars tend to know each other on sight.

It’s possible Angry Surfer is a sign that things are getting too crowded, and that’s leading to frustrations that might soon become wider-spread. Or maybe, as Dickerson said, this is just a case of one angry guy.

One of the weirdest things about Angry Surfer is that even though he’s a fierce localist, it’s really hard to tell if he is, in fact, local, Dickerson said. He kind of came out of nowhere.

“Nobody knows him and I know all the regular bore-tide surfers,” Dickerson said.

Most of the time tide riders are giving high-fives and taking video of each other, he said. He has never heard of a conflict anywhere close to what has been happening with Angry Surfer. His attitude is way out of the ordinary, he said

“Adam,” the guy with the GoPro, didn’t want his last name in print, fearing that Angry Surfer might look him up on Facebook and get violent in retaliation for putting the incriminating video on YouTube. (Had the Angry Surfer’s board hit him during their altercation, it could have knocked him out. And that could have been deadly. He wasn’t eager to experience that again, he said.) Alaska State Troopers have taken at least one report recently about a hostile surfer making threats, according to trooper spokeswoman Megan Peters.

“I don’t know this dude” Adam told me Tuesday. “… He’s a violent person that just snaps for nothing.”

Surfers everywhere observe a generally understood etiquette on the water, Dickerson explained.

“If somebody is on the wave in the ideal position before you, you should give them right of way, and you shouldn’t get in their way if you can help it,” Dickerson said.

Some people online have criticized Adam for not observing the etiquette and getting in Angry Surfer’s way. Sometimes run-ins like theirs are hard to avoid, Dickerson said.

“Those people don’t understand the situation,” he said.

The bore tide is different from waves at a surfing beach, he said. The tidal wave constantly changes form. A person can be in the ideal position for a little while and then not be, he said.

And the bore tide wave moves for miles, so you can ride the wave for a while and then come up on someone else waiting to catch it. It can be frustrating, if you’re an advanced surfer, to run into an amateur who doesn’t get out of your way. And, because the wave only comes twice on a day with perfect conditions, the stakes are high.

Jeff Hoke, an Anchorage firefighter, has been surfing the bore tide regularly for 10 years. He ran into the Angry Surfer last week, he said. Both of them were standing on shore and they talked about taking opposite sides of the wave so they wouldn’t get in each other’s way, Hoke told me. As he was paddling out, the guy turned ornery, Hoke said. He told Hoke to stay out of his way. Angry Surfer yelled that he was 43 years old and that Hoke (who is 35) should “respect his elders,” Hoke said.

When Hoke objected to the guy’s tone, the guy said, “Well, I’ll shoot you in the – – – – – -in’ face,” Hoke said.

Hoke wasn’t expecting that. (Later he considered reporting the threat to the troopers but wasn’t sure what he’d say. He couldn’t identify the guy except that he had light hair and was, apparently, 43.)

The wave was coming, distracting them both. Hoke told the guy they could finish their conversation in the parking lot. I’m not sure exactly what Hoke meant by “finish the conversation,” but Angry Surfer didn’t want to find out.

“He actually got off the wave early and snuck up the rocks so I couldn’t find him,” Hoke said.

Distributed by MCT Information Services