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I have noticed in past two weeks of an increased number of Orange-Tips and it started with mostly females with my first sightings of year being 8 females and only 2 males. A few days ago I saw 2 males and again two days ago, 5 males and just today, saw 10, all males, 3 females but the females were quite a distance (a few hundred yards or more) from the males.

This year over past several years, I have seen an increased numbers of Orange-Tips. A number of other people have also been saying there was an increase in OTs where they see them. Could it be the warmer weather? Anyone else noticed more OTs than usual?

Not especially. Wherever I've gone there have always been small numbers and I don't think I've yet seen more than low teens anywhere.

Don't forget that the number in the air at once is not necessarily a simple function of the size of the breeding population. It can also indicate that there is synchronisation in emergence. I don't think we can gauge actual numbers without considering the length of the flight period, which we obviously don't know this year.

Consistent hot weather can telescope the staggered emergence, so the first emergers are still flying when the later ones emerge, giving the appearance of an abnormally large population.

I'm not saying numbers aren't up this year - just that it would be hasty to jump to conclusions too soon.

Guy

PS - since writing that I saw David's reply - but as I'm not in the UK I can't comment on that.

I know it would come down to a number of factors and I'll probably have a clearer idea once their flight time is over. Emergence times could be a factor as I was rearing small white last year and had 5 chrysalis outside and all 5 hatched on same day.

Do females have a shorter lifespan than males or is it about same? As I said above, I noticed more females two weeks ago and now there are eggs on most of the cuckooflowers and I am only observing mostly males and just was wondering what happened to the females.

I think females have a shorter life-span than males. Males of many species emerge first and yet they are also generally the last to be seen at the end of the flight season. I put this down (speculation) to the much greater energy demands of producing eggs. A female butterfly may lay 100 or more eggs - that's quite a lot of concentrated goodness to leave the body!

But I've never measured the life-span of an individual butterfly, so it could also be that males emerge over a more spread-out period.

Guy

Thanks Guy, well I read a message that head of BCNI wrote and he seems to think that Orange-Tips are more numerous in NI than previous years, but we won't know for sure until we have all the reports of them and compare it to other years. Since they overwinter as a chrysalis, it wouldn't be down to early warm weather I would think as I would have thought the early and cold winter would have had more of an impact but I don't know much about the weather effects on early stages of butterflies compared to say predators or other threats to them prior to them becoming adults.

i went to a site near Spaldwick, Cambridgeshire yesterday and was amazed at the abundance of Orange Tips compared to the previous 4 years.

Charles

I have seen huge numbers at times this year. I can't remember how it compares to previous years though because I may just notice them more now but I think numbers are up on last year at least.

Unlike previous years, my local authority have not yet wasted the publics money, and cut the roadside verges. So we are seeing dozens of Orange-tips on the way to our transact, but virtually none when we get there. So the records may end up showing, that 2011 was a bad year for Orange-tips at Danebury.

Regards Gruditch

Hi all,
What Guy Padfield says is totally spot on....synchronised emergence...that is exactly what I am seeing here. I counted 50 plus on one day. Females emerged pretty much a day behind the males...since then the weather has been clear allowing a mass explosion in numbers. The B side to this is that numbers will suddenly sharply drop....


Iain.

Before last year I had never seen an OT in my garden, this year I've seen 2 or 3 a day. The same with my local cemetery although with higher numbers.

Cheers

Lee

Here in the West Midlands there are certainly more around than in recent years, in fact one of my neighbours, who only has a passing interest in butterflies was only commenting the other day to me about this.
Up until last year I would usually see the occasional Orange Tip in my Garden. This year they have been present almost every day for the past few weeks.
If I sit out in my chair I can almost guarentee one will be along within a few minutes.
This year I have also seen far more females than usual in the garden.

Cheers,
Neil.