www.ukbutterflies.co.uk

I had an email today regarding 2011's Big Butterfly Count. I haven't had time to digest the results but it seems that fewer butterflies were recorded this year (although, as ever, there were a few species whose numbers rose).


Thank you for taking part in Big Butterfly Count 2011!
With your help we counted more than 300,000 butterflies and moths, giving us some fascinating results...

Butterfly numbers were down this summer. The average number of individual butterflies and moths seen per count dropped by 11 per cent compared to last year’s event. Many species were less abundant. The dismal summer weather, the coldest in nearly 20 years, was undoubtedly to blame. Butterflies need warm conditions to be active, find food and mates and, if female, to lay eggs.

The Common Blue suffered one of the biggest declines compared with 2010; its numbers fell by 61 per cent. Other species faring badly included the Brimstone, Small Copper, Comma and two common immigrants, the Painted Lady and Silver Y moth.

The Gatekeeper topped the Big Butterfly Count chart this year, up from third place in 2010. Also moving up this year were the Red Admiral, which was almost twice as common in 2011 than last year, and the Speckled Wood, which increased by 80 per cent.

Although not a great summer for butterflies, there was a phenomenal response to the Big Butterfly Count this year, with 34,300 people taking part and twice as many counts submitted as in 2010. Many thanks to everyone who helped us ‘take the pulse of nature’.

See the full results and find out how all the species fared in 2011 on the Big Butterfly Count results page.

http://www.bigbutterflycount.org/2011ma ... X5,1L5V2,1

I didn't take part in the count but i agree with the results. it has been a terrible year in the garden. but on the other hand it seems to have been a good year out in "the wild" i wonder if there is any correlation between good garden years and available nectar outside of the garden.

Chris

We had a discussion on here a couple of years ago as to whether an apparent decline in sightings was due to fewer butterflies or fewer opportunities to go and see them in the poorer weather . At the time of the discussion it was pointed out that a particular species ( Silver Washed Frit IIRC ) that was having a very good year because of the good summer were actually the product of eggs laid in the previous year which was a bad summer and that species had supposedly had a bad year .
FWIW , I do agree that the Common Blue has had a poor year here in Sussex .

For what it's worth, I'd say in my experience this year has been excellent for Speckled Woods, Red Admirals, Peacocks, Pearl Bordered Fritillaries, Holly Blues and Purple Hairstreaks.

On the other hand it has been poor for Common Blues, Small Tortoiseshells, Small Whites and Small Coppers.

David M wrote:I had an email today regarding 2011's Big Butterfly Count..................
"The dismal summer weather, the coldest in nearly 20 years, was undoubtedly to blame."

As a scientist, I found the use of the word "undoubtedly" in the e-mail quoted by David very questionable. Surely, there are many possible factors - increased use of insecticides, increased use of crop sprays on the plants on which butterflies feed, greater levels of predation, as examples. I agree that the dismal summer weather almost certainly didn't help but we shouldn't ignore other factors that may well be contributing to butterfly decline.

Mike

The Butterfly count aside,I am wondering what has happened to all the large whites this year.It can't be because of the weather,as I hardly saw any in the first part of the year,when the weather was good.Are too many chemicals now being used in gardens and on their food plants?
P.J.U.

MikeOxon wrote:

David M wrote:I had an email today regarding 2011's Big Butterfly Count..................
"The dismal summer weather, the coldest in nearly 20 years, was undoubtedly to blame."

As a scientist, I found the use of the word "undoubtedly" in the e-mail quoted by David very questionable. Surely, there are many possible factors - increased use of insecticides, increased use of crop sprays on the plants on which butterflies feed, greater levels of predation, as examples. I agree that the dismal summer weather almost certainly didn't help but we shouldn't ignore other factors that may well be contributing to butterfly decline.

Mike

There is precious little science in the big butterfly count......I looked at a few of the returns and there were butterflies that had clearly been reported as a result of mis-identification.

The survey does have its uses though, and I'd like to see them extend it to the full 'season', i.e. from late March through to late September if at all possible.

P.J.Underwood wrote:The Butterfly count aside,I am wondering what has happened to all the large whites this year.It can't be because of the weather,as I hardly saw any in the first part of the year,when the weather was good.Are too many chemicals now being used in gardens and on their food plants?
P.J.U.

Here their late season numbers are up on last year over some game cover that contains brassicas, which is the second year the field in question has had such a mixture. My sadness has been the lack of Common Blues but again I think there has been a drop in the amount of vetches available.

Great project with crazy results (for a Central European).

Gatekeeper? We call him extinct (due to huge area shift/drift to west)

P.J.Underwood wrote:The Butterfly count aside,I am wondering what has happened to all the large whites this year.It can't be because of the weather,as I hardly saw any in the first part of the year,when the weather was good.Are too many chemicals now being used in gardens and on their food plants?
P.J.U.

For me I wondered where GV Whites went and Peacock butterflies, must have seen less than 10 peacock butterflies the whole year and most of those I saw around August, saw only one between March-early July, one in late July and rest in August.

As for large whites, could it have been down to parasites (small brachnoid wasps)? I noticed large numbers of parasited caterpillars last year, saw them all over the place. However I did notice since farmers in my local patch had planted turnips instead of barley in 2 fields, numbers of Large Whites in August were very large in those fields (saw 30+ in a few minutes of driving close to the field when passing one bright sunny Sunday afternoon, 40+ in nearby field. Less small whites though)

I did the big butterfly count and only saw 2 Red Admiral, 2 Small Tortoiseshell, 1 large white and a Green-Veined White.