Escaping the giant duck

 The neck extended under water.
Everyone thought it was a plesiosaur.
But it was a duck whose neck extended.
Exended twenty meters and it's body grew greatly.

Then it rose from those eel infested waters.
It clmabered over small islands with only one objective.
To eat us whole of course, so we in turn found refuge.
Little subterranean shelters and corridors.

But we knew one day it's beak would break through,
Thus some of us would be gone forever.
The duck looks so adorable from outside of our hiding shelters.
But when it engages it is worse than any existing land monster.

The question is, what made it grow so fast.
What made it so incredible aggressive.
And how do we survive in a world with a giant duck hunting us.

No it's not a goose, yes it's neck is long.
It bites us and eats us.