Pond Boss Forums INTRO Questions & Observations Mergansers

As far as they're being scaup - that's just the closest picture I found this A.M. to what they looked like. The female was colored pretty close to a mallard hen (to my uneduckated eyes); maybe a little darker head and neck). The male was very dark (black?) in the front, very light (white?) in the middle, and the same very dark hue at the tail - kind of like a Belgian Banded cow.

Now, as to terminology for their behavior, you tell me. They were both disappearing under water, for at least 30-45 seconds at a time (possibly longer, I didn't time them). Is that diving or daubling or ???