Scar Close NNR

Dales National Park

SSSI

 Ingleborough

Site Details 

Recorders:  Andrew Hinde + Terry Whitaker                              Length 2389m           Walk Time: 45mins

Within the Ingleborough National Nature Reserve, the transect goes across Scar Close, at the north west slopes of Inglebrough.  An area of sparsely wooded limestone pavement supporting a wide diversity of calcareous grassland species. The site is unique in having areas of peat on the pavement that support more acidic tolerant species. The transect was established primarily for Northern Brown Argus but in recent years has had a large colony of Dark-green Fritillary. The discovery of Small Pearl- bordered Fritillary in 2007 highlights the importance of the transect monitoring approach for some of the key butterfly species in the upland 

Sections

S1 is dominated by Green-viened White

S2 is the favourite for Dark-green Fritillary  but is also seen throughout

S3 is favourite with Peacock and Northern Brown Argus is seen

S5 is favourite of Small Pearls  along with S8  but also seen throughout

S9  is also a favourite for the Vannesids  

S10 owards most species present at lower levels

Results 2024  Very limited data

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

TRANSECT REPORTS

Results 2023  limited data

County wide 2023 results reflect  the 2022 Heat and drought  with Small Tortoiseshell and Peacock nearly halved for the second year against their 5 year average. Red Admiral arrived in force in July and took advantage of soft nettle growth of the rains and had their best year ever. Drought sensitive species on thin soils were badly hit,  particularly Dark -green Fritillary and Northern Brown Argus but also Ringlet, Green-viened White and Small Heath.  Less drought affected species along with the hottest June on record built even more on gains last year leading to Comma, Brimstone, Holly Blue and most Browns  having a fantastic year reaching all time highs. A increase of 9% overall was mostly due to sheer numbers of Meadow Browns and Gatekeepers ment 2023 nearly pipped 2014 as best year in modern times.  Most noticeable was the large differeces between moisiture retaining mineral soils of the valleys and thin, dry limestone or sandy soils. A large number of damp grassland, hedgerow and woodland  dominated sites benefitted hugely with 3 sites seeing more than 50% increase . A smaller number of thin, chalky, sandy or craggy sites did badly some down up to 25%.

Scar close produced very limited data for the second year. We can be fairly sure Northern Brown Argus was likely down but not a disaster but continues its slow declien and Small Pearl-bordered Fritillary had  another good year and this species is much improved  over the last 4 years.  We need a good year of data to be sure of these important trends on this valuable site with 20 years of  good recording. 

Results 2022    limited  data

Although the data has too many gaps to have alot of certainity  we can see the skippers have gone absent this year along with Orange tips.  Peacocks are very much lower. Overal counts compared to the peak in 2019 are about half  largely as a result of this and of course the Painted Ladies that year. You can also guess that Dark Green fritillary and the Small Pearls are also holding well.. if not increasing.  

Longer term we can see a very strong improvement in the SPBF and a equally strong decrease in the Dark green Fritillary.  Northern brown Argus is showing a slow decline  along with an even steeper decline in Common Blue .  Overall numbers of al species is upwards in common with all our monitored sites. The repacements for teh Lycaenids are all  grassland species  starting with a sharp improvement in Small heath from 2015  meadow brown and Ringlet began to appear in increasing numbers each year along with Green Hairstreak. Almost all species suffered catastrphic losses in summer 2017