February 21, 2016

The worms that turned

Last week, on Tooting Common, I found that a short section of the path I walk Scout along each day was liberally strewn with dead earthworms of at least two species, both immature and mature individuals.

That part of the path hadn't flooded so they hadn't drowned. Some, but not all, showed small blisters, but they hadn't all been squashed; there was a mature ash tree above, and I wondered if they might have been dropped from it by birds. Matt Shardlow of Buglife says it is more likely that they were poisoned by something toxic being spilled on the path and soaking into the ground – perhaps de-icer from the nearby train line, or herbicide.

The next day, all the dead worms had gone – probably eaten by birds, which I hope weren't affected by any toxins in the worms. A few paces on, the path was totally clear again. I have kept an eye on the vegetation and none has died back there since I discovered them. It's a mystery.

My friend Cheryl Tipp who is Curator of Wildlife and Environmental Sounds at the British Library has told me she's seen exactly the same thing on a path by Stevenage train station. What on earth is going on?