Swarth Moor  SSSI


 Dales National Park  Open Access

Site Details

Recorders:   Terry Whitaker,  Ian Court  , Mik Cardus, Mick Lambert, Steve Ryder, Frank Morgan, David Owen     Altitude 220m        Distance 1540m           Walk Time: 45mins

Situated to the south and part of the Ingleborough National Nature Reserve (NNR), Swarth Moor SSSI comprises an area of raised bog, fen and small areas of carr woodland. This is the key site for Small Pearl-bordered Fritillary in the Yorkshire Dales National Park and is one of the primary reasons for establishing a transect at this site. 


S1 sometimes has very high counts  particularly of Ringlets which maybe management dependant  and can attract species from other sections 

S2 sees the appearance both Dark green and Small Pearl bordered Fritillaries and good counts of Smal lHeath

 S3 is damp area and favoured by Green veined white and Orange Tips in particular. 

S4 is similar. 

S5  favoured by Large Skipper and growing number of SPBF. 

S6-7  sees most SPBF  

S8-10  grassy area sees the most DGF and Small Skipper 

Results 2023

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%.

Swarth Moor had a poor year with overall numbers down 30%.  The main reason is the big decline in more drought sensitive species namely Ringlet, Small Heath and Green-viened white which was just about universal trend across Yorkshire.   Dark-green Fritillary has seen regular falls one of the largest has been these last two years being absent this year. Although on many site Small Pearls have done well here it had its second very poor year and is in a  bad situation!

Transect reports

Results 2022

Overall an average year down 3% although with some big differences between the species.

 Small Skippe bounced back doubling in numbers enjoying the hot summer while large skipper  was a tad down.  Whites in general had a poorer season  but even so well up on last year. The vanessids were all down but not nearly as much as the majority of sites where they collapsed with no second generation, due to poor nettles. 

Both Fritillaries were down drastically to just a quarter of last year. SPBF are still on a steady decline down three quarters over the 20 year monitoring period which is disappointing. Meanwhile DGF as elesewhere in Yorkshire continues to enjoy a rapid long term rise although almost universally they are down this year. 

meadow brown Enjoyed a good year as elsewhere and compensated for a good deal of the loses. 

Ringlet and Small Heath were very slightly down in line with much of the county.

Results 2021

Small Skipper is much reduced from 2019 peak as was Large Skipper but this is a trend amongst all sites. Common Blue has reappeared but Green Hairstreak was absent this year.

The vanessids did badly apart from Small Tortoiseshell which  did well here and boomed on many sites.  SPBF is pretty consistant while DGF has greatly increased which is a pattern of the last few years. Small Heath boomed as in many sites while Ringlet faltered. Meadow brown was close to average