Brown pellets in loft

[dan1w]

Just moved into a Victorian terrace and lifted some boards in the loft. There were quite a few of these brown pallets. They seem to be contained to this one area.

At first I thought they were droppings, but they’re very uniform and could maybe be some sort of pupae shell?

The loft timbers show signs of woodworm infestation, but it looks historic.

Any help identifying these would be much appreciated.

 

[footprints]

Looks like rat poo to me, usually slightly bigger than a grain of rice.

 

[jacko555]

Looks like blowfly / maggot casing to me

The pic is fuzzy though

 

[mattylad]

Maggot casters, bag them up and go fishing with them