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

Staveley West  like its neighbour had a very good year nearly double the county trend in overall numbers and up 14% overall . Species trends prety closely follow the county with massive increases in Gatekeeper (4 fold) and Meadow Borwn (2 fold) while Ringlet dropped dramatically to just a fifth of last year illustrating teh drought here was much worse.   Unfortunatly the affects of drought ment  Small Heath was not seen this year. However the same species showed a marked improvent just next door. Speckled wood  doubled as did Comma. Brimstone tripled and Holly Blue  reached an all time high along with Red Admiral. Peacock really suffered  here as it had these last two years but Small Tortoiseshell managed to come back where in most localities it had a even worse year after an atrocoius 2022.  Common Blue boomed after last year sun. Drought sensitive Orange Tip and Green-viened White fell back as they did in most parts.

This year is a somewhat  down on 2020- 21 and well down on the recent high in 2018-19 But even so there are soem interesting new patterns emerging. In particular  increasing number of Small heath since 2019 and now Marbled White is a great addition following just a couple of years behind as the species has had several dispersal events in recent years leading to lots of new colonies including along Nidderdale.  Loss of the Large Skipper woudl indicate the grasslands are evolving and maybe dryer and over the years butterfly numbers are increasing by about 10% over the last decade. Most species this year are following the county trends with the Skippers, Whites and Vanessids being very much reduced partcularly Peacock the exception being ,as everywhere else, Comma had a good year more than double last year . Most of the browns with the exception of the more moisture loving Ringlet were well up but didint compensate completey for all the other losses