Michael Viney responds to readers queries and observations on nature.
Last summer, swallows built a nest under the eave where the chimney protrudes. They returned this year built an annex, just a floor, on to the nest where one of the flock rests at night.
Jim Ryan, Clonmel , Co Tipperary.
Swallows repair and build up old nests at the start of the breeding season, but building on a patio to accommodate a large brood is new.
In mid-July a swarm of flying ants flew into my garden before a thunderstorm. The resident ants were frantically running around and there seemed to be communication between the two groups. After the rain the flying ants left.
Mary Walshe, Glasnevin, Dublin 9.
In summer the worker ants rear males and queens, all with wings, but keep them underground until climatic conditions, including high humidity, trigger the nuptial flight. All the nests of a particular species release their sexual ants into the sky at the same time, perhaps to prevent cross-breeding. The males die soon afterwards, but the mated queens return underground to lay eggs for the next 10 or 20 years.
Michael Viney welcomes observations at Thallabawn, Carrowniskey PO, Westport, Co Mayo; e-mail: viney@anu.ie. Include a postal address