Painted lady will steal your heart away

CLOUDS of butterflies and a haze of day-flying moths rose from beneath our feet as we walked the Seven Heads in west Cork on the glorious last day of May 2009.

I hadn’t seen so many butterflies together since I was a child. Vast influxes were reported on web postings from all over Ireland. They flew in their thousands in Kerry, the Burren, Kinvarra, Lough Corrib and Donegal where, “painted lady’s were touching down on the Teelin to Bunglass boat and taking off again in their hundreds”.

I spell them painted lady’s to distinguish them from painted ladies, quite another species, most often seen “flying it” on high heels on Saturday nights. Painted lady’s migrate into Ireland ever year but this year came in huge numbers along with brown-grey moths known as silver ys for a distinctive mark on their fore-wings.

The breeding centre of the painted lady’s is North Africa, from which they set off in early spring. and the moths in mainland Europe. In mid-May, a group of British birdwatchers visiting Morocco reported waves of these butterflies streaming northward over the Atlas Mountains; they somehow estimated that three million were passing every hour.

Shortly afterwards gardens in Kent and orchards in Surrey were so inundated that their owners could hardly find a square foot of naked ground.

The phenomenon is not unprecedented; in 1980 painted ladys were so plentiful in Britain that numbers were impossible to calculate. Similarly in 1952, 1966 and 1969. Some, along with their cousins, the red admirals, and silver y moths would continue their journey northwards to reach the Shetlands, Iceland and the Arctic Circle.

This year, exceptional rain in the Moroccan desert nurtured food plants and the butterfly population irrupted. The strong south-easterly winds on and before the June Bank Holiday were perfect to carry them. They glided and darted down the golden avenues of sowthistles and hawkbit on the shaley paths above Dunworley, Co Cork, with the blue sea twinkling below them in the heat of the holiday afternoon.

I noted, among the throng, a few red admirals, carried on the same winds across Biscay and the Celtic Sea. Both painted ladys and red admirals are powerful flyers.

They skim over hedges and meadows, dodge through orchards and forests but, unfortunately do not always manage to dodge cars. By the Tuesday, the arrivals were dispersing and heading inland.

I saw many flying across the road as I drove to Bandon and was told of hundreds flitting over the Bandon River.

By now, they will be all over Ireland.

The caterpillars of painted lady’s do not eat cabbages and are not pests. Eggs are laid singly on the leaves of thistles, mallow, nettles and other wild plants in June.

They hatch a week later and the tiny caterpillars spin the leaves around them and feed within – the small “purses” can often be seen on nettle tops.

They grow rapidly and form a chrysalis, which is suspended from a leaf. Two weeks later, in August, a gorgeous winged creature emerges from it. It hauls itself out of its sheath, pauses to let the wings dry and strengthen, and then takes to the air. It will fly for a few weeks until the onset of winter claims it.

Painted ladys do not survive the Irish winter but red admirals, hatching a little later, sometimes do and pass the months in hibernation. In September, they feast on windfall apples and sometimes get drunk on the fermenting juice.

On the south coast cliffs in this lovely weather, native species were also abundant, whites, small heaths and common blues.

There were, as yet, no small tortoiseshell, one of our commonest and most beautiful native butterflies. It enters our homes and sleeps behind curtains or cupboards in winter. In spring, it wakes and flies, laying eggs in late May.

The new generation produces September offspring, some of which survive the winter to propagate in the following year.

I hope that this year tortoiseshells will be a common sight – last summer’s wet weather was a disaster for them. In the absence of a home brood, it’s to be hoped that the migrants that normally reinforce the native population in August arrive in substantial numbers. With bees in decline, butterflies are increasingly important for crop pollination.