Countywide, after a warm winter  April turned  cold, very wet and dull and everything just about stopped and it was near impossible to transect walk all month. By May  there were already  losses  among our spring species being  down a third in numbers.  June brought Arctic winds, a complete reversal of  the Hot June of 2023 when nine  species reached all time highs here and across the UK.  For the  first two weeks of this June  temperatures  were 8’C cooler than  in 2023 around  a frigid  9’C  with  only 5 good days of sun at the end of the month.  The  first three weeks of July had  the same theme of  cool and damp with 5 warm sunny days at the end. Transect walking for many  was very difficult.  The  persistence of the cold and damp over such a long period had a devastating effect with numerically two thirds of our butterflies in the critical later stages of their development; mortality was very high. It was  also one of the longest June  ‘Lulls’  lasting from late May to the beginning of July. When the main flight  season did arrive it  was  slow to build up  and there was no usual peak. Better weather in August helped  save the second generation and very unusually numbers actually went up at the start of September.

  Losers

        For many species it was a triple whammy after  the heat and droughts of the previous 2 years and  last July’s poor flight period this year made it a perfect storm. Overall, annual numbers were down 41% against the average and 45% down on last year.  Half our species were down more than 50% and a quarter down more  than 70%. The Lycaenids, Vannesids and the Fritillaries were amongst the worst affected. Many transect walkers did not see  a single Common Blue, Small Copper, Holly Blue, or Brown Argus until late into their 2nd broods..  Four of our long term declining species Common Blue, Small Heath, Small Skipper and Green-veined White  had  their worst year ever recorded. 

The Winners and less bad losers 

      Northern Brown Argus  had an exceptional year up near 50%  Other species bucking  the trend were Brimstone and Marbled White. The  damp  loving Ringlet on many limestone/dry sites  were up a half  while on most wet sites they fell by a half.  However if it wasn’t for Ringlet holding up the overall numerical losses, this year would have been significantly worse. It often happens when Meadow Brown has a very poor year, like this one, Ringlet does proportionally better, and vice versa in a warm year. 

It has all happened before… many times.    

It was our worst year since 2016 but nearly as bad as 2009  when numbers  were  down 50%.  2024 comes after a run of 6 relatively good years since 2018  along with  rapidly rising temperatures including 2 of our hottest summers which were followed by two of our best butterfly years in 2019 and 2023. It is  likely 2024 was a blip

Whitcliffe saw a significant fall in overall numbers which is large part was down to loes amongst the drought sensitive speces namely Ringlet and Small heath  contrasting with meadow Brown managed to  go up on average which was a common acrooss teh county. Also suffering was Wall and Speckled wood and although Peacock and Small Tortoiseshell were better than last year against the average they are still well down but at least showing now signs of recovery. Reversing much of these declines was Small Skipper which boomed up near three fold and recorded its highest ever numbers. Comma  also had a bumper year along with Red Admiral both having there bast year ever as they did across the county. All the whites were well down this year but it was great the Brimstone appeared for the first time!  Gatekeeper  or maybe a Marbled White next?

Slightly down on the average hides some big changes with our species . However numbers are still holding up well compared to the recent all time peak in 2018/19 that almost all sites experienced.

The decrease in small skipper and increase in Large  mirrors many sites as do the quite laregg decrease in the Cabbage Whites. In common with other sites Orange tip had a better year  but here numbers  were up 6 fold .  Small Copper seems to be in a downwards trend in many localities  but is very variable . Holy Blue reappeared after an absence in common with many sites .  The vanessids is where most of the losses occured particularly Peacock but also Tortoiseshell was only  one fifth of last year  with only a very small 1st and 2nd generation. Peacock numbers were porr in teh spring unlike most locations and actually came back in August but only for a week before fading away very quickly. This likely reflects temperatures are considerabbly cooler   by 3-4'C than the lowland where both species made almost no showing after early July.  In complete contrast and in harmony universally with other lowland locatiosn Comma  had a good year after  zero for last 3 years.  Speckled wood like most of teh browns had a godd year here slightly up but on many locations it showed a doubling in the September generation. Wall although half of last year held its ground and the longer term it is rising significantly which is also true of other locations Wall is on teh up as it is in Derbyshire peaks. Meadow brown was very much up but the big winner which bucked the county trend was Small  Heath which at this site is showing a longer term  increase, plus a slight second generation,  even if numbers this year were a bit down on the boom and ten times higher than 7 years.  Is this climate change or is it  habitat?  is a question begging an answer

An outstanding year 49% up on the average when most sites were down. 

Most species were up  and the trends of 2020 are somewhat repeated  with the strongest performers being Small Heath  doubling its previous high and booming throughout the county and Small Tortoiseshell continuing tits boom as elsewhere .

 Wall was good which matches eleswhere.

Loosers were Small White  Large Skiper and Ringlet along with Holy Blue  which matchs the rest of Yorkshire 

Even without the migrant Painted Lady numbers were a bit down with significant losses of  Small Copper and Green-veined White, which may well be due to the drought conditions of early spring.  Migrant Red Admirals held up well, as did Small Tortoiseshell having a good year.   Small Heath numbers continue to rise strongly.  Ringlet numbers are well down after a hot summer of  2019 and the drought of 2020.