When Predator Became Prey

I saw a willy wagtail yesterday
His tail was switching every different way
He darted from the fence line after flies
And he had evil intent in his eyes.

I watched him snatch a butterfly from play
He stripped the parts he would not eat away
He took the meat and left the wings behind
And to suffering of others he seemed blind.

But then i watched a 'hobby' flying by
And he would not be chasing butterfly
He grabbed poor willy carried him away
And the predator had now become the prey.

The legs wings or feathers hobby did not eat
He only had the best of willy's meat
I found one wing black feathers and his head
And i concluded 'willy wag' was dead.

In Nature it has always been this way
The predator will end up as the prey
And willy wag who ate the butterfly
Was taken by a hobby flying by.