HOW LONG?

How long will I stand?
Been here since WW2,
But then I was 600 feet inland,
An under ground bunker, that has seen
its day.

I have stood the test of time,
But now I am an island unto myself,
Surrounded by a fearsome ocean,
I stand only on wooden pilings,
Most rotted away,
But I am still here to say,
If it wasn't for those pilings,
I would be nothing but a pile of concrete &
steel,
A place where fish would make their home,
And come to play...

So now I still stand,
A skeleton of my past glory,
With 15 inch gun turrets,
Covered in seaweed,
So this warning do heed,
I don't know how much longer I'll be standing,
As now I am, for the birds, a landing! 

                                               (ed)