Do slugs and snails hibernate? I meet a few snails in sheltered nooks and crannies, but where are the slugs?
Eithne Scallan, Maudlintown, Wexford
Snails hibernate in winter by retreating into their shells and sealing the entrance with mucus which hardens into a protective disc called an epiphragm. They are sometimes found in groups with the shells stuck together by the mucus. In very dry summers they aestivate in a similar manner to avoid drying out. Slugs are usually active all year round, but they burrow deep into the ground during very dry or very cold weather. They also try to avoid rain falling on them and only emerge when it stops.
Although the pale tussock moth is of local distribution in the southern half of the country, we have seen it a few times on our farm. The adult stage of this moth normally appears in May or June and the caterpillar in late summer or autumn. It overwinters as a pupa. On January 29th we found a newly hatched adult on the inside of our sitting room window. The caterpillar must have come into the house and the pupa hatched early in the warm room.
Jim Fox, Coursetown, Athy, Co Kildare
I was sitting up in bed reading about midnight on January 30th when I heard at least two blackbirds singing their hearts out. We have blackbirds in the front and back gardens; they act as if they owned the gardens, and they fill the place with their song, but never after dark and certainly not at midnight.
Pat Walsh, Dublin 11
Blackbirds occasionally sing at night; it is possible that one mistook street lighting for the dawn. Males sing to advertise their territory and attract a mate, or, in the case of young males, in an attempt to establish a territory. This is the time of year when they start, and a young male may have been eager to get a head start on the competition. It is unlikely that there were two birds singing as male blackbirds do not engage in song duels, and females rarely sing. They have, however, a very wide range of song in their repertoire.
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 as location is sometimes important to identification or behaviour.