Flight Periods - Have they really changed?

[NickB]

Was discussing this with JackHarr. We are both planning for our particular target species and trying to predict what the season will be THIS year! (Will this cold snap put the season back, bearing in mind that we have not had a cold snap quite like this in the UK for a while, for instance..........?)

From the literature currently in circulation about flight times, it has become apparent that SOME species seem to be emerging earlier than indicated; from Jack's long experience this shift happened quite suddenly in the 1990's. We are talking about 2 weeks earlier on average than the perceived wisdom would indicate - tho's for some species, up to a month...
I say some, because others seem to be around the same times as they have always been.... whites for example...

Is this the experience of others' ?
Which localities and which species have you noticed changes in?
What other factors may have contributed to this?

Maybe we can build up some interesting snapshots from around the country

[Dave McCormick]

Well, I don't know much about where I live yet, need to look at the records I made of species here and see, but I was told that in Dublin area, Holly blues have now got a 3rd brood which can be found until October or November. Before it only had two broods, but not in past few years,

Also, its been usually to wet here in winter, but in past two years, Red Admirals have been able and have overwintered here.

[NickB]

Interesting Dave. I saw Holly Blue in every month of the season from April to September this year (at different sites) - but I would only expect that to be two broods overlapping slightly rather than 3.

There were certainly signs of 3 broods from the Small Heath in my part of the world around Cambridge, for instance, and last year was, like most places, by no means exceptional weather wise!
(Cambs&Essex BC (Sharon Hearle) has successfully asked the managers of Newmarket Racecourse (chalk downland) to leave a large un-mown area in the centre of the track, with a marked improvement in the SH numbers over the last couple of years (And not just SH benefit...). It just goes to show that managers are generally sympathetic to a well-reasoned case with a simple and easily-understood solution. )

N