Watch the clock.
Rowers start at 15-second intervals near the BU Boathouse, so they compete against the clock and not each other. You won’t be able to follow a race from start to finish or even get a good sense of who is winning at any given point in time. One clue of how the boats are doing is, if you’re watching down the course, if you see a bow with a higher number in front of one with a lower number. That means they are racing at least 15 seconds faster through that point on the course. You’ll need to catch a glimpse of one of the race results boards to see who has won a particular race.