Mergansers in the South Branch

We didn't see our first Common Mergansers (Mergus merganser americanus) in the South Branch this year until February, and we're only now seeing them regularly.  Mergansers are diving ducks (in contrast to "puddle ducks" like mallards).  They appear lower in the water, and swim underwater to catch food.  Their legs are set further back on their bodies; and while that aids underwater swimming, it makes it harder to jump up out of the water to fly away.  That's why most diving birds take a running start along the surface before they become airborne.