If I asked you to picture a harvest mouse, you’d probably conjure up this classic image: a tiny acrobat balancing on a stem of grass, perhaps hanging on with a semi-prehensile tail. Glancing at a distribution map of harvest mice in Worcestershire (Worcestershire Mammal Atlas), you’d be forgiven for thinking that this BAP species is scarce. Only 26 records exist from 1995-2007! Weighing little more than 6g, Britain’s smallest rodent is notoriously rare to spot, thus is woefully under-recorded in Worcestershire.
After a successful assembly late last Autumn, myself and four folks agreed to push the creation of a Worcestershire-based mammal group. Spearheaded by James Hitchcock and Johnny Birks, this small nucleus (or ‘administrative back-end’ according to Johnny Birks!) organised a harvest mouse training day for local mammal enthusiasts. The trust’s own Feckenham Wylde Moor was selected as the ideal training site, due to the presence of fantastic reed beds.
On a frosty morning, the mammal group and a merry band of volunteers met at the entrance to the reserve. Johnny passed around his collection of harvest mouse nests, whilst explaining the technique to search for them (akin to David Bellamy ‘swimming’ through grass). We then marched to one of the site’s reed beds, and were let loose to search for our own harvest mouse nests. We were looking for a characteristic woven ball, constructed from stripped green leaves.
Searching for 5-10cm diameter nests initially seemed a bit daunting, however regular whooping heralded the successful discovery of a nest. Whilst this was going on, I spent a good while tearing into tussocks of frozen reeds, emerging with nothing but numb finger-tips. But luck struck, I found a nest! The ball was so small and so delicate… a real natural treasure.
After around an hour of searching, the mammal group bid farewell to the morning volunteers, before retreating to feed and water in a suitably warm den (or a local cafe). The second lot of eager volunteers (accompanied by radio 4’s Brett Westwood) arrived at around 1:30pm, and the fun began again.
In total, 19 harvest mouse nests were found (2 breeding 17 non-breeding)… the ice and mud was worth it in the end!
I would like to thank the Worcestershire wildlife trust for allowing us access to their beautiful reserve, to Johnny Birks for teaching the survey technique and to all the volunteers who attended the mammal group’s first ever event. Hopefully we can all help ‘fill the gaps’ on one of Worcestershire’s most enigmatic mammals!
By Josh Humphries