Coral Shield

As I glide 

I feel free

But then I hide

I had to flee

As I felt someone shied

Then there came more for free

I need to find a shield 

There was some coral near

In the quiet coral, I dwell

My shell wiggles, slow and steady

My back a fortress, my legs a spell

I peaked to tell

Then was unleashed a surge of human waste

Plastic bags and tented nets

Debris a bitter taste

That makes my face upset