Eye on Nature

While out walking late one evening I came across neon-blue snail markings on a wall. What's happening here?
Michelle McShortall
Whitehall, Dublin

The snail or slug trails approaching the luminescent area were clear, going by your photograph, and the coloured markings of the trails in the centre suggest it was feeding on something on the wall, perhaps a bioluminescent lichen.

A big fungus is growing on the lawn outside my office, in Ennis, between a horse chestnut and a holm oak. What is it?
Austin Slattery
Lahinch, Co Clare

It could be honey fungus, a dangerous parasite of broadleaf trees, from looking at your photograph. I’d suggest the RHS website for advice, at iti.ms/1FIOGwd.

I have just plugged in an electromagnetic pest-control device to keep the mice out. Will it affect the bats?
Mary Murtagh
New Inn, Co Cavan

An electromagnetic field may well disturb bats, but many of these devices also combine ultrasonic waves – and these will definitely disturb them.

Michael Viney welcomes observations at Thallabawn, Louisburgh, Co Mayo, or by email at viney@anu.ie. Please include a postal address