Whose pawprints are these?

I’ve got an exciting new toy! It’s not much to look at. A black plastic tunnel. But it’s great at creating suspense. It’s a tool for finding out which small mammals visit your garden, by capturing their pawprints.

It’s very simple. You put the tunnel along a fence or other boundary in your garden. You put some bait in the middle of the removable black plastic plate, paperclip a piece of paper at either end, and put a strip of special safe ink either side of the bait. The animal has to walk through the ink to get the bait, and on their way out leaves inky pawprints on the paper.

We tried it out baited with mealworms (I’ve yet to discover an animal that doesn’t love the disgusting looking things). The ink is a mixture of black poster paint and vegetable oil, so is safe for animals to lick off their paws.

Here are our results from the first night of monitoring.

Hedgehog and mouse pawprints — Pawprints from the mammal tunnel

There are definitely hedgehog prints, but I found it quite hard to tell from the diagram what the smaller prints were, so for the second night I decided to add an infrared camera to the tunnel, which together with motion trigger software showed us this: (nb. this is a speeded up version which only includes when the animals are actually in the tunnel).

Mystery solved: mouse and hedgehog.
Not really a huge surprise, as we knew we had both in our garden. But it’s fun to get their pawprints and film them. On a more practical note, if you didn’t know what visited your garden, this could be a good way of finding out. And more importantly, you can submit your results to the National Mammal Atlas Project.

You can get the tunnels from the Mammal Society, and submit your results there too (nb. They don’t come with infrared cameras – that was my own modification).