Conor Garland scored, and Thatcher Demko made 22 saves for the Canucks (0-4-2), who remain the NHL's only team without a win and failed for the seventh straight time to get coach Bruce Boudreau his 600th NHL victory.
"My job is to help us find a way out of this," Boudreau said. "So I'll be doing whatever I can to see what I can do to get this thing turned around. Their job should be, individually, 'What can I do to turn this thing around?' That's what I'd feel if they booed us off the ice like this. I would hope our pride kicks in."
Dahlin put Buffalo ahead 1-0 at 5:35 of the first period with a point shot that deflected past a screened Demko on the power play. Dahlin was already the first defenseman in NHL history to score in the first four games of a season and is now the first defenseman in Sabres history to score a goal in five straight games.
"I'm not trying to think about it," Dahlin said. "I was into [the defensive] zone for 80 percent of this game, but when situations happen out there, I try to score, so it feels good when the puck goes in."
Dahlin may downplay his scoring streak, but it has left a strong impression on the rest of the Sabres.
"He's making plays that kind of reminds me of when Erik Karlsson was at the top of his game," Anderson said. "He was doing things with the puck that you just wouldn't expect him to do because he had that confidence, and [Dahlin] is there in his own game. I'm not comparing him to Erik, but I'm comparing him to that confidence, that swagger with the puck that he has to be able to make those plays. He's just playing loose and letting his skill and ability take over right now."
Tuch, who screened Demko on Dahlin's goal, made it 2-0 at 15:18. Jeff Skinner forced a turnover in the slot that left Tuch behind the Vancouver defense for a spinning shot under the blocker of Demko.