F/8.0, 1/2000, ISO 800.

Common Merganser 

Why was the math book so sad?

It had a lot of problems.

Interesting Fact: Common Mergansers spend much of their time afloat, loafing, fishing, and often sleeping on open water. They may form flocks of up to 75 individuals. They often swim in small groups along the shoreline, dipping their heads underwater to search for prey and then diving with a slight leap. Often when one bird dives in a large group, the others follow the leader and disappear. ( Common Merganser Life History, All About Birds, Cornell Lab of Ornithology )