How is your grass coping with guinea pigs eating it all?

[millimat]

Our lawn isn't the best to start with, but this weather means that there's no recovery time when the guinea pigs munch it all. What can I do to save the lawn but let them run on the grass?

Ours has large rectangles that look scalped .
There's no way of keeping a 'nice' lawn with little furries. We try and water the patch once they moved on , but it takes a while.
Our lawn looks like weirdy alien crop circle (but rectangle) with just the buttercups left behind.

But ..........they leave little losenges of intensive garden fertiliser