We are no 3 days post whelp. We had a slight panic when Beryls temperature shot to 39.3 after being around 38.6.

Has anyone else got experience of their bitch trying to push food out of their box and moving all the covers into one pile regardless of where the puppies are. She's also been moving food with her mouth into little piles around the box. Shes been a great mum till this point ... but she is displaying some strange nesting behaviour.

Any help or reassurance most welcome!

Quite normal,  the digging and rearranging is down to the discomfort of after pains.

Burying food is either keep the area clean or save food for later.

I have had both behaviours with mine,  which is why I now only use shredded paper until this stage passes. I have had pups getting under the bedding, with the risk of suffocating.

The food burying too,  as I feed her in the whelping box.

My girls pups were born on 20th, so 3 days old hasn't been hiding food but takes great delight in rearranging her whelping pen, then gets onto my bed and rearranges my duvet

No two bitches are the same, but just to ask whether you had her in for a 'clear out' shot after you felt she'd finished whelping?    I know not everybody does this, and with me and my C.Sections, it wasn't necessary but if by chance she has retained birthing material, she may well be feeling uncomfortable, and for sure, it needs to come out.

I'd feed her outside the box in any case, so you can move the food once she's had enough?    I have had bitches rearrange the bedding which can be a pain in the you-know-what in terms of covering up the puppies.   

I'd also check her teats - if the milk comes in too fast, sometimes newborn puppies can't draw it off fast enough = the potential for mastitis.   Also re getting stratched - we've had to nip the pointy tips of very young puppies, to avoid this.

That is primitive canine behaviour, we get lucky enough to see it from time to time.
Even they don't know why they're doing it, just driven to raise their brood no matter what.

If they dig, it could be a sign of discomfort. Our previous house has ruined carpets through the girls digging post whelp. Not a problem for us as we understood. Retired now so we can take pride in our home lol.