Andrew Cogliano scored for the Ducks, who wrapped a four-game trip and are on a 5-1-1 stretch.
Anaheim's John Gibson made 26 saves. He has been dominant against Vancouver, coming into the game 6-1-1 with a 1.37 goals-against average and three shutouts against the Canucks.
Vancouver got to him at 9:53 in the opening period. Daniel Sedin's shot from the faceoff circle bounced off Gibson and right to Gagner, who batted in the rebound.
In the third, Biega put Vancouver ahead 2-1 with slap shot from the blue line that cleared traffic and found the corner of the net.