Dog sniffing and scratching door casing and skirting board!

Has anyone experienced their terrior chasing the skiring boards around the room? I think we may have a mouse as Henry is becoming obsessed with this and sniffs heaviy like he can smell something in the door casing etc... Its becoming an issue as he is doing it all the time now. Has anyone else had this? I have just read on the internet that someones dog did this to get his tea quicker and it was more of a learnt behaviour. Henry is doing his at all times of day though!!!!
Thanks

My sister's golden retriever did this obsessively once - turned out it WAS a mouse behind the skirting!

Tilly did this too and guess what?

it WAS a Mouse behind the skirting board
few days later we found it drowned
in the dogs water dish

i reckon it was suicide

Thanks for the replies thats what I thought you might say!!! I'm goin to leave traps down next week to see if i can catch it!!!! I don't fancy ripping out the skirting board and door casing!!
What a pain!!

My old dog did a similar thing, for the same mousey reason! He caught it one day out in the conservatory and carried it into the living room - its tail dangling out of the side of his mouth.

When I retrieved it the mouse was untouched! Monty was a mongrel but with a lot of lab in there somewhere and had the soft jowls of the lab - he hadn't damaged the mousey at all

I carried it round to the field at the back of my house and let it go - would have loved to have heard the tale it told the family when it got back to its home -'Sorry I'm late dear, but.........'

more like accidental death that way no-one's to blame....