A Busy Day

There were Mergansers everywhere.  They're such fun to watch, especially in a group.  I watched about eight of them diving for food and even though they weren't swimming in a tight group, they all dove at the same time.  I wondered what the signal to dive was and which one gave it.  I should have done some serious animal behavior studying along the way.  I guess it's not too late but I'm going to need to find a duck expert I can tag along with.