Crafty Critters and confusion?!?!?!

So I went up to the allotment yesterday morning. It started out a nice day as the sun rose over the horizon but by 8:30am it was pouring with rain.

The rain kept easing and then coming down full force then stopping for a while and after a little 'umming and arghing' I decided to bite the bullet and get my but down to the plot.

As was expected really it rained more than it didn't so I though I would get the greenhouse tidied out at least.

In the greenhouse I noticed a tell-tale critter sign again....

Again the hole has appeared in the compost in the crate in the greenhouse. Mice??

 Again in the tub where I had my bell peppers I noticed a little burrow hole so the critter that I thought wasn't there last time maybe is. At this time I also noticed a few sunflower casing on the floor. So the little devil has been scaling my greenhouse shelving and taking my sunflower seeds which were spread and drying on newspaper in the greenhouse. This has to stop and probably explains what kept happening to my cauliflower seedlings so I decided to get my boots on and take the whole tub outside to empty it out and have a good look.

I keep a set of wellies and thick socks in the greenhouse for dirty/cold work but I always give them a shake just in case spiders have set up home. I shake the first one out and put it and the sock on my foot...then I turn to the second and guess what.....

The little devil has nibbled my sock and turned it into a Sunday sock!

Yep...it has definitely been in my boot too. Fortunately it wasn't too damaged and was still wearable...this of course is the point I dubiously look into my wellie...and what do you think I find??

A wonderful mouse pantry.

That's right...it was full of sunflower seeds, the cheeky little devil had obviously decided to store some up in it's own little pantry for the winter to come. I removed them carefully but no mouse was inside so after putting on my second sock and boot I took the tub outside to start emptying it out.

Whilst going slowly through the tub and carefully emptying it out I found plenty of tell-tale signs.

Can you see all the empty sunflower seed casings?

There were plenty of little burrow marks in the compost and as I slowly emptied out I found a lot of empty sunflower casings. Either my little visitor has been very busy or he's been inviting friends round for parties.

Problem is I got to the VERY bottom of the tub and still no actual sign of the mouse...veryu confusing and also frustrating.

I disposed of the compost in the compost bin and then checked the rest of the greenhouse. No signs of entry anywhere else...no signs of droppings at all. So what am I to believe. I have never known such a crafty critter. The only evidence is that in the photos aboe...even the paper and fleece were untouched.

I am going to see about getting some humane traps but I don't hold old much hope of ever getting my hands on this devious little devil. Anyone got any tips that will help me catch him?? Or do you think it could be something else entirely?? I really am at a loss here.
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