The large white butterfly is out in force this summer
by Paul Cormacain 12/08/2005
THE large white butterfly seems to be out and about in large numbers just about now.
This butterfly is less common in the west of Ireland and the north of Scotland, but very common in Wales and England.
It is to be found through most of Europe, and has a foothold in North Africa. It ranges eastwards across Asia, as far as the Himalayas. In most of Europe numbers of this beautiful flying insect are quite stable but with some declines in places and some increases in other places.
Studies in Ireland have shown that the large white is usually quite common.
In some years the numbers are increased by immigration, but after years of exceptional abundance the population number is known to crash.
Some folk are less happy than others with the larger numbers and these folk tend to be farmers and gardeners.
The large white likes brassica, and that is the problem. Cabbage and brussel sprouts are firm favourites, but it also likes oil seed rape and nasturtiums.
Then again, some folk grow nasturtiums to encourage the butterfly to visit their gardens. Beautiful flowers, beautiful insects. It must be very difficult for the large white to know just where it is welcome, and where it is unwelcome.
There are usually two generations each year. Winter is passed in the pupal state, and it is usual for the adult to appear in April. The first brood peaks in May. These creatures breed and lay eggs, frequently on cabbage.
The eggs are laid in batches of fifty or more. The subsequent larvae start off life in a gregarious state, then gradually go their own way and end up solitary. Because of the mustard oils absorbed when they are eating, they are unloved by predators, which helps their survival rate.
However, they are attacked by parasites, which hinders their survival rate.
Adults tend to be missing in July, but the eggs turn to larvae, the larvae become pupae, and towards the end of July they commence to reappear as adults. August and September are the main months for the second brood. If the weather is good enough, a third brood may appear in the autumn. Lets hope we have a third brood this year.
As I was writing about the large whites I was watching some of them come into the garden, fly around for a time, then disappear. Also in view were some meadow browns, another popular and common insect, an insect without a preference for brassica.
In many habitats, the meadow brown is the most abundant butterfly. At times they can be seen in large numbers flying low over the vegetation, and even in dull weather they can be out and about when other butterflies are inactive.
It is reckoned that the spots on the wings of the Irish and north Scottish meadow browns are slightly larger than others. Regional variety going mad.
As well as there, the insects live in England and Wales, and extend east across Europe, usually south of 62 degrees north. The range extends into the Urals, Asia Minor and Iran.
They like open grasslands, heathland, coastal dunes, road verges, our garden, clearings and waste ground. Only one generation appears each year, with the first adults starting to appear in June.
They are around in July, August and September, but occasionally a few new adults can be seen as late as the end of October. Some folk take the view that the late insects are proof of a second brood, others feel that the maturation period can be very variable.
Females lay their eggs on grass, and the subsequent larvae feed during the day. They over-winter in the grass, and have been known to feed if the weather turns very mild. Pupation occurs in the grass.
The large white and meadow brown butterflies seem to be very common at the present time. But then, if they were not common now, they would certainly not be common in the winter. I hope you see your fair share of them.
Coming Events
Friday 1st July to Wednesday 31st August - Castle Espie is hosting a Feathertastic Trail, a self guided trail for all the family, sounds fantastic. Contact Espie on 028 9187 4146 for details
Saturday 13th August - National Trust flower walk, at 1030, at Rowallane Gardens National Trust search for wildlife at Strangford Lough.
Sunday 14th August - National Trust great day out for all the family at Florence Court, Whale and Dolphin Watch at Portmuc Islandmagee. Details from Andrew Upton on 028 4483 0282
Tuesdays l6th, 23rd August - Environment Matters Talks at 1930. talks by local experts on environmental topics, in Portrush Countryside Centre, details phone 028 7082 3600.
Tuesday 23rd. Wednesday 24th August - Bat nights at Roe Valley Country Park, phone 028 7777 6532. Bat nights at Castle Archdale Country Park, phone 028 6862 1588
Tuesday 23rd, Wednesday 24th, Thursday 25th August - Bat nights at Colin Glen Forest Park. more from them on 028 9061 4115
Thursday 25th August - Birdwatch Morning at Castle Espie. at 1030, phone 028 91874146
Ulster Star
12/08/2005
