Rabbits nesting box

[KrauseFarm]

We recently gave our doe a nesting box, she is currently 28 days pregnant and should be kindling soon. Right now she’s seems more interested in chewing at the box and scratching at it instead of building a nest. Should this be a concern? Any tips?

 

[NatJ]

She's probably trying to dig a burrow and build a nest.
I would suggest adding enough hay to stuff that box completely full, and then she can dig a burrow in the hay and arrange it to suit herself.