wrote in message
...
The British Isles is currently having the most spectacular
immigration
of butterflies for decades, if not centuries. Painted Ladies are
arriving in their tens if not hundreds of millions.
snip Anyway, the weather aspect started over the winter when the
Atlas
Mountains in North Africa had ideal growing conditions for the
plants
that the butterfly caterpillars feed on – plenty of rain and
adequate
snip
But, and this is the big question, could
population explosions of less benign insect such as locusts be
correlated with El Nino events? If it were possible to predict such
explosions based on weather data, then suitable eradication methods
might be possible in the source breeding grounds.



.... we've noted the 'swarm' (can't call it anything else really) of
Painted Lady here in Dorset over the past few days - peak was
Monday/Tuesday.

Your post reminded me of my time on Masirah island (off the mainland
coast of Oman) 1971/72, when we had to send special returns of
rainfall to the Anti-Locust Research Centre - David Pedgley was key in
collating the data then and a search has turned up this ....

http://biopesticide.ucr.edu/locust/locust.html

where, despite being retired, he is still 'active': this report shows
that control of locusts is very much in the minds of those concerned,
and I remember a briefing sheet being sent by David to us in the early
70s which explained that by collating rainfall data especially (other
parameters used), they could predict such 'explosions' of activity as
you describe. What the current state of the science is I couldn't say.

Martin.



--
Martin Rowley
West Moors, East Dorset (UK): 17m (56ft) amsl
Lat: 50.82N Long: 01.88W
NGR: SU 082 023