After a couple of years of watching mice scampering around the garden I had the idea to great a little camera equiped mouse house. The objective was to see if I could get the mice using it, maybe even as a nest, so that I could watch a little more of their behaviour.
I made the box during January 2021 from 15mm ply wood. I had the local hardware shop cut the pieces to size before assembling everything at home.
The entry hole size was 25mm, small enough to keep rats out but not too small for the mice. I also added some air holes at the end of the box furthest away from the entry hole.
Prior to being installed the outside of the box with a typical wood protector.
I installed the box right at the bottom of the habitat pile next to the hole in the fence used by the hedgehogs. The habitat pile is made up of twigs and cuttings taken from the garden bushes and I has seen mice in and around this quite ideal environment many times.
Once installed I piled on another bunch of twigs so that it was completely hidden.
A video camera of the type shown below was installed in the box to offer a view of the inside.
As a final touch I put some shredded newspaper into the box, L’equipe circa 2015, to provide some cozy bedding material. I like having material in the nesting boxes as it is easy to spot any disturbance and therefore activity.
The view inside the installed box as it was installed in January 21 is shown below.
I had to wait until Mid February before the first mouse entered into the house, a moment caught for posterity below.
Over the nest months the mice were in and out, the typical visits being very fleeting and only for a few seconds. The box may have been used as a food store but never as a nest site. The longest visit by a mouse into the house was on the 26th July, when one stayed nearly all day.
This also provoked the most interesting behaviour I managed to witness when a second mouse entered the already occupied box. Unfortunately I didn’t record it on camera but the resident went absolutely beserk, leaping all around the box, until the intruder retreated.
However unfortunately in October I decided to end the experiment and take the mouse house out of the garden. During the Summer we had started to let our two new cats out into the garden, roaming freely day and night, and I’m afraid this has had a major, and rather detrimental impact on the mice.
They became by far the favourite prey of the cats who killed several in a short period, despite which I continued to catch some in the humane trap in the garden shed. So there were, perhaps still are, quite alot of mice around and at least some capable of evading the lurking cat menace.
However I didin’t think it wise to encourage more mice into the garden so the mouse house was removed.
After taking it in I opened it up and had a bit of a nose inside. I didn’t find anything startling, a couple of nice spiders aside.
There were lots of little black empty seed cases which I guess the mice had been eating. The only ‘clue’ I found were the presence of sycamore seeds.
There are Sycamore trees in the gardens of a couple of my neighbours and they were obviously providing part of the mouse diet.
To be honest I didn’t really manage to learn a lot with the limited means that I deployed. The mice are very small, secretive and highly mobile.
Prior to the intervention of the cats I was considering putting in place a much more elaborate mouse house, perhaps with several interconnected chambers. This may have provided a more interesting environment for them, and one in which they would therefore have spent more time.
However with the cats in the ascendency I think I will leave the little fellas in peace and hope they find a nicer and safer environment somewhere else.
Chatou Nature Blog 