The go-to method for surveying small mammals, a ‘Longworth Trap’ consists of a metal cube and a skewed metal tunnel, with a tripwire that snaps the tunnel door shut, trapping its occupant. We’ve stocked 103 of them with straw and a tempting buffet of vegetables, grains, and casters (fly pupae!) and are here the following day, to see what we’ve caught.

We survey two sites: Russell’s Mead and Morris Mead. The first, Russell’s Mead was a tangle of sedge and willow, and presented us with our first occupant.

We remove the tunnel over a plastic bag, and a squirming chestnut body fires out like a rodential cannonball. Tapered nose, satellite-dish ears and a fleshy pink tail identify our guest as a mouse. Due to the size, and lack of Yellow ‘bib’ of the Yellow-Necked Mouse, we can identify them as a Wood Mouse, Apodemus sylvaticus.

The mead produced another Wood Mouse and two Bank Voles, Myodes glareolus. Blunter noses, ears, and generally rounder; sporting a rufous fur coat.

As always though, the best came last. The trap felt light to the touch, and there was a heavy possibility it may have been triggered by marauding slugs. However, upon tilting it, a tiny, suitably named Micromys minutus sprawled into the bag – a Harvest Mouse. Weighing as little as a 2p coin, they resemble a Wood Mouse that’s shrunk in the washing machine.

Usually, we handle the small mammals via “scruffing” – pinching their necks as their mothers would’ve done, calming them as they’re sexed. However, the delicacy of our Harvest Mouse meant it was easier to goad them into a little glass jar. When it came time to release, a sprig of Hemlock was placed into it. Avid climbers, the mouse shuffled up with all four legs, using its tail as a fifth limb, before parachuting off into the foliage. Morris Mead started strong, with two Wood Mice, and the Bank Vole’s sister, a Field Vole, Microtus agrestis.

Then came the Shrews.

Our first guest was a Pygmy Shrew, Sorex minutus. With the build of a pom-pom, and eyes, legs and ears barely visible, it’s hard to comprehend it as living - if it weren’t for the incessant moving.Insectivorous, they’re led by their truncated noses, as if pulled by a shuddering, restless invisible thread. Most only live through one birthday, and with a metabolism only matched by the speed of their hectic movements, they must eat every few hours. Thus, after a quick look, they’re released.

At the beginning of the survey, every Pygmy Shrew was met with wide eyes and a group of elated volunteers, and though still elated and wide-eyed, there were also some sarcastic groans of “not another one…” by the time we hit our eighth one!

Four Common Shrews, Sorex araneus, were also caught. Equally long-nosed and rotund they resemble the Pygymy Shrew only a little larger, and with a more contrasting dark upper-side to pale underside, the Pygmy’s having a more gradual contrast.

The final Longworth emptied, and the numbers were tallied:

• 4 Common Shrews
• 8 Pygmy Shrews
• 2 Bank Voles
• 2 Field Voles
• 5 Wood Mice
• 1 Harvest Mouse

Giving a grand total of 6/8 of the potential species being caught, with 22 individuals – and no doubt who the most numerous was!