What’s this slithering mass of caterpillars? Readers’ nature queries

Eye on Nature: Ethna Viney on dragonflies, damselflies, beetles and cuckoos

Could you explain this slithering mass of black caterpillars that I saw on a nettle in mid-June in my garden? – Laurence Speight, Derrygonnelly, Co Fermanagh
They are the caterpillars of the peacock butterfly. The butterflies should appear by the end of the month.

In Wicklow I was lucky to see and take photos of a cuckoo feeding and flying off with a caterpillar. Liam Kane, Blanchardstown, Dublin
It was feeding up for the long flight to Africa.

I saw this fly, which I think is a damselfly, when walking near Melmore Head in Co Donegal. – Claire McAneny, Rosguill, Co Donegal
It is the male, common blue damselfly. The female is green and black.

This photo of a large (80mm) dragonfly was taken on the bog.Mike Egan, Ballivor, Co Meath
It is the four-spotted chaser. It could be either sex; later the female turns light blue.


We live on the shore of Lough Swilly on the Inishowen Peninsula. On many wonderful explorations of the beach I've noticed semicircular, rubbery things and wondered what they are. – Sarah Maguire, Buncrana, Co Donegal
They are the collar-shaped egg mass of the moon or necklace marine snail, Euspira catena.

I noticed a green-backed spider hanging out in our mint. – Jim Callan, Tallaght, Dublin
It is the cucumber green orb spider, Araniella cucurbtina. It hides under leaves to spin its web.