Sense Sonnet - Pumper

Whale Nap

A whale in water must breathe air,
And at the surface must do so.
Inside the whale, oxygen there
Let's the whale underwater go,
And stay for quite a while until
The next surfacing must occur.
Whales will sleep as all mammals will,
But cannot oversleep for sure.
Near the surface a whale can float,
Up be the head, down be the tail.
When time to breathe the whale does note
The need to wake, and must not fail.

If fast asleep, the whale stays down
Too long submerged, the whale will drown.