Tuesday, August 29, 2017

Painted Ladies

Lately a few painted lady butterflies have begun to appear in Teesdale and Weardale, wafted in by warm winds from the south. It's nothing like the spectacular invasion we enjoyed in 1996, when the first arrivals appeared in early July and bred on thistles to produce a second generation, so that there were enormous numbers by early autumn. Sometimes late invasions arrive in early autumn, as they did in 1903 (see below).














Painted ladies are noted for their infrequent but spectacular invasions and some of the largest of these, according to F.W. Frohawk in his Complete Book of British Butterflies published in 1934, coincided with wet summers in 1879 and 1903. 

This is how Frohawk described them:

"In 1879 the first migratory swarm appeared in North Africa in the middle of April. At Barcelona and Valencia enormous numbers occurred at the end of April and reached the island of Minorca on the first three days of May. On June 15th. vast swarms passed over Sevres, flying all day in a north-westerly direction. Similar flights were seen at Strasburg passing in countless numbers to the north, At Angers, on June 10th., an immense swarm flew over the city; it was estimated that between 40,000 and 50,000 passed along a single street in one hour; they were flying so low that pedestrians were inconvenienced by them. At Bisheim, on June 8th., the same phenomenon was observed and their numbers were so enormous that they darkened the sky. On June 11th. the flight that passed through Steyer in Austria, was so great that between one and two o'clock p.m. 90 to 100 per minute were counted in the breadth of 100 paces, the swarm being estimated at 1,000,000. Similar vast swarms were encountered in other places. 

Again, in 1903, a sudden and great invasion of these butterflies occurred in the autumn. They arrived in hundreds of thousands along the southern and eastern coast and dispersed over the whole of the British Islands. The flight was so vast that it extended from the Shetlands to the extreme south of England and Ireland. Their numbers were so prodigious that they swarmed along the whole of the eastern seaboard, from Durham to Kent, and wherever observations were made on the Scottish coast, they were abundant. The first arrivals of this vast invasion reached our shores on September 18th., and the flight continued for five or six days, their numbers increasing daily."














These butterflies look particularly attractive when you view them from below, with the sun shining through their wings that then resemble stained glass windows.












This individual was in Weardale yesterday, feeding on knapweed.



9 comments:

  1. We had a lot about 5 years ago, not many since!

    ReplyDelete
  2. Replies
    1. I hope you do - they are such a delight

      Delete
  3. I'd never heard of those invasions before, Phil. It must have been amazing to behold! This has been one of the better years for seeing them in our garden. Their underside is, in my opinion, one of the most attractive of the species we get in UK.

    Best wishes to you - - - Richard

    ReplyDelete
    Replies
    1. Couldn't agree more Richard - the slight transparency of their wings makes them light up on sunny days

      Delete
    2. .... and best wishes to you too!

      Delete
  4. I've yet to see a Painted Lady this year, a year that appears to me to have been a very poor one for butterflies in general. I'm told there were lots of Painted Ladies on the Galloway coast in the last few days. Cheers. Brian.

    ReplyDelete
  5. Not too good here, either. Last year we had swarms of red admirals, commas and peacocks visiting our fallen plums - this year just in ones and twos. Seen more small coppers and walls than in recent years though.

    ReplyDelete