What has made this a good year?

[hilary]

From what I've seen and from this forum, it seems to have been a good year for butterflies. I was wondering if anyone has any particular ideas as to what has contributed towards making this a 'good' year?
I know the weather is supposed to be one of the most important factors but much of the last 18 months or so has been unusual and as it seems to have suited almost every species of butterfly I am wondering if there is any patricular thing about it that may have helped?
Liz

[David M]

It's a very good question, and I'm sure even the more expert on here would struggle to answer it.

2012 was appalling and 2013 saw winter extend right up to the end of April.

Okay, from late May through to mid June and then largely from early July onwards, conditions have been pretty good, but how does that explain the great year most UK butterfly species seem to have had?

Did the cold start to the year kill more butterfly predators than usual?

Is it just that we've become used to seeing so FEW butterflies that this year has been notable by comparison?

Could it be that butterfly numbers are equally as high last year, but due to the inclement weather far fewer were actually seen in 2012 by human beings?

[Paul Harfield]

It's a very good question, and I'm sure even the more expert on here would struggle to answer it.

I do not think anybody will really know the answer, but I am sure there will be lots of varying suggestions from experts to novices. Here is mine, from a novice

Perhaps the start of it was the horrendously wet summer we had in 2012. Maybe horrendous for us, but for the plants I am sure it was one of the best years for a long while. Judging by my garden all the plants certainly did unusually well, everything was very lush Maybe the larval stages did exceptionally well on this lush vegetation and a higher than normal percentage survived through to later stages. The prolonged winter of 2012/2013 maybe removed some of the predators/parasites from the equation. All this resulting in a bumper emergence once the summer had kicked in.

It would be interesting to know if there were any species that did not do well in 2013

[Pete Eeles]

I remember giving an on-the-spot brain dump to a journo a few weeks back, which resulted in this:

http://metro.co.uk/2013/08/29/butterfly ... r-3927538/

Cheers,

- Pete

[Mark Senior]

As I have posted before , all the butterflies we have seen this year ( except immigrants ) came from eggs that were laid last year . 2012 was of course ( supposedly ) a very bad year for butterflies but in reality it cannot have been that bad , they must still have been about , bred and laid eggs even if we did not see them perhaps because so often we were huddled out of the rain indoors .
The factors stated by jackz423r also come into the equation as to whether butterflies do well in a particular year but we just do not know enough about this subject .

[NickMorgan]

Up here the number of spring butterflies was certainly lower than an average year. Small, Large and Green-veined Whites were in short supply for the first generation and Orange Tip numbers were lower than normal. On top of all of the rain in 2012 we had flooding in July and December and I think that wiped out eggs, caterpillars and chrysalises. The number of Ringlets and Meadow Browns was low where I do my transect close to a river, I think again because of last year's flooding.
When we notice a great number of butterflies was in August. The second generation of whites was very numerous along with Peacocks and Small Tortoiseshells.
There are also a lot of caterpillars around just now, so fingers crossed we could be in for decent numbers of butterflies next year too.

[hilary]

I too saw very noticably high numbers of Peacock, Tortoishell, Large and Small White. With the others I'm not experienced enough to have an opinion (until the yearly statistics come in!). I addition to all the things already mentioned I was hoping that all the new agricultural wild life initiatives (and the general increase in public interest and knowledge) is giving an extra boost to the very mobile butterflies in that they are able to better outrun their predators and move into fresh areas. But it must be very difficult if not impossible to measure those kind of things.

On the down side Green subsidies, I often drive past a new solar panel array covering many acres, and thought it is a waste of good land but that the grassland below must be offering a better living to many invertabrates, even if its mown from time to time, than wheat or potato fields. But yesterday I saw they had weed killered the lot and am angry that the owners are getting a supposedly 'green' subsidy from funded by everyone that uses electricity. I hope they get a dust-bowl effect and have to spend their profits on cleaning them but just in case I shall have think who to write an angry letter to!

[essexbuzzard]

Was it such a good year? Certainly it was a very good Summer,by recent standards at least. But the Spring and (so far) Autumn have been pretty aweful!

My,totally unscientific opinion is that,in the Summer,caterpillars and chrysalises were able to progress more quickly, making them liable to predation for a shorter period,due to the higher temperatures in July this year,increasing the survival rate.

I think one of the reasons we prticularly enjoyed this Summer is because it was so unexpected-it took us all by surprise!

[David M]

Spring was pretty ordinary really, but it all kicked off late May/early June when we got that first prolonged warm spell. Numbers seemed to explode very suddenly and unlike in previous years, we never really had a lengthy miserable spell to rein things back in.

Early season Orange Tips, Speckled Woods and Whites seemed less common than normal, but presumably the eggs laid by those species developed quickly and healthily thereafter, resulting in high numbers later on.