Shark in the Trees

I'm a shark!
Goodness me,
What is this?

What the hell!
I see trees?
Am I mad?

Delusions.
That's the deal,
Just not real.

But it is!
Dear, dear me,
Need water!

How on earth?
I'm surrounded
By huge trees!

Someone help!
I must go;
Must swim home!

Do you care?
Don't just stare!
I need help

Oh my my
Could I die?
Love my wife.

What was that?
Hit my head.
Wow, that hurt!

Seen my kids?
Seen my wife?
They're my life!

Don't belong
In forests.
Need water!

How did this
Come to be?
I hate trees!

In danger!
So I am;
I'm so stuck.

Help me please
Need to live;
Need to swim!

Oh! No, wait!
Oh, hold on!
Was I wrong?

Don't you laugh!
I was wrong.
See no trees.

A nightmare
Was asleep
I dropped off!

Oopsy do
I was daft
I am okay

I can see
Family
But no trees

Oh, hold on!
Confusion:
What's a tree?