Michael Viney responds to your queries and observations on nature.
We noticed some snails in our garden pond. They are whelk-like, about two centimetres long, and breeding profusely. They seem to be the large pond snail, which are considered a pest and carry liver fluke. Is it safe to have them where children and pets play?
Ruth Murphy, Ranelagh, Dublin, 6
They are not the great pond snail (Lymneae stagnalis) which is much larger, more like five centimetres tall; and whereas all snails only eat vegetable matter, the great pond snail also eats decaying animals, and it only carries liver fluke in streams in sheep country. Your snails are more likely to be the wandering snail (Lymneae peregra) which is the commonest water snail and will just clean up the pond for you.
I saw what looked like a small gecko or lizard in a warm corner of a rocky field near Crookhaven, in West Cork. It was grey in colour and had sludgy yellow/green markings.
Heather Sweetnam, Douglas, Cork.
It was a common or viviparous lizard, the only native reptile in this country. They are very plentiful, and as cold-blooded animals, they need to warm up in the sun before they use up energy hunting.
Edited by Michael Viney, who welcomes observations sent to him at Thallabawn, Carrowniskey PO, Westport, Co Mayo. E-mail: viney@anu.ie. Observations sent by e-mail should be accompanied by postal address.