Bank YWT  

Thorton le Dale

Site Details

Recorders: Ian Popely,  Graham Oliver  and Paul Cogan                Distance :  925m   Altitude: 145m     Walk Time: 45mins

Ellerburn Bank is a 3 ha. grassland site sloping south-east on oolitic limestone on the southern edge of the North York Moors near Pickering. Despite its modest size, it is one of the most extensive areas of unimproved limestone grassland remaining in the North York Moors . It was notified as a SSSI in 1983 and has been managed as a nature reserve by the Yorkshire Wildlife Trust (YWT) since 1966, having been informally managed for nature conservation perhaps for the previous decade. The flora and fauna of the site is exceptional for the region, with over 150 species of plant recorded including large displays of Cowslip in spring, orchids in early summer and Gentians in late summer . Flowering plants of regional note include Dropwort, Woolly Thistle, Saw-wort, Fly Orchid Ophrys and Greater Butterfly Orchid. The site is noted for its extensive Lepidoptera fauna , including butterflies of regional note such as Dark Green Fritillary  and Dingy Skipper Erynnis tages, and the site also supports a population of Glow-worm Lampyris noctiluca. Management of the reserve currently consists of low-intensity winter grazing by Hebridean sheep  and rotational scrub clearance.


The upper, northwestern margin borders an agricultural field and consists of a Bronze Age earthwork (a double ditch and bank) partially covered with Hawthor and Blackthorn  scrub, S4 (record bank side only ) and S5  whilst the lower, south-eastern side bordered by forestry S7, consists of a patchwork of taller grass and Gorse following the lowest path.  S1 follows the north east boundary dry stone wall and is favoured by Wall brown and Dingy skippers and lizards. The southern edge is sheltered and  changes to isolated gorse bushes  S3 returns to teh entrance and S4 follows the ditch southwards.

2023 Results

County wide 2023 results reflect  the 2022 and  2023 spring 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 mositure 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%.

Ellerburn Banks calcareous grasslands are succeptible to drought and although drought resistant species prospered those there were not significantly decreased . Overall numbers were down 11% whiel county waise were up 9% but it was a mixed picture. The big winners were Marbled White and Meadow brown that have thrived in last years hot summer and this year very hot June.  Speckled wood did surprisingly well as they did across the whoel of Yorkshire in likely their best year ever along with Brimstone and Red Admiral. Drought sensitive Ringlet and Small Heath suffered badly but Common Blue was  even worst . Wall and Dark-green Fritillary suffered  badlyeverywhere . The vanessids all did badly ( apart from Comma) and only in the dales  did we see the beginning of recovery of these species.  

Transect reports 2020

2022 Results

Small Skipper is having a bad time in Yorkshire but here it it significantly worse possibly due to the dry nature of the site and it follows the county pattern of the 3rd year of decrease. Large skipper although better than last year  is also on a down. Dingy skipper follows the county pattern of being a bit down on the good years, Brimstone again follows county trends in being up . The whites dont follow the county trend being well up on this site while down in the county. However Orange Tip was well up  as in the county trends . Small Copper showed a loss as in the majority of sites. Brown Argus was  down on this upland limestone site as it was on other rockrose sites while the migratory form was well up on its alternative foodplant cransebill down in the lowlands. Common Blue was also down but held its ground on other sites.  All the vanessids were down apart from Comma which was  well up and follows trends across the county with neither Small Torts  or Peacock producing a second generation and later having a very grim time,  Dark Green Frits were also down as in other parts of the county. Speckled Wood boomed as they did elsewhere particularly in later broods. Meadow Brown boomed and Ringlet was well up  more so here than in other sites . In common with the county Small Heath was down along with Marbled White, 

2021 Results

Overall numbers were down somewhat compares to the boom years of 2018-19. The large skipper did not reappear after a rapid fall last year and even teh Dingy skipper was down possibly the effects of last years drought spring. Green viened white had a good year as tehy tend to enjoy a wet summer.  Small Copper was also well up  but Brown Argus  had its best year since 2018 . common blue in contratst continued a trend of decreasing . The vannessids in common with most transects had a bad year particularly Comma. Speckled woods and most of the browns were down apart from Small Heath that had a boom similar to other transects  and Ringlet had its best year  for some years. Unfortunately Wall was not seen thsi year after better numbers last year but we know they tend to hate wet summers like 2020-2021.

Things in general still in good shape.

Results 2020

After two cracking good years numbers have fallen back only marginally and held up well  during teh poor summer of 2020 but it may well have benefitted from the long hot dry spring. Skippers were down along with Green viened white and Speckled wood which could be related to the spring drought but its great to see the Wall back in good numbers and Small Tortoiseshell after years in teh doldrums have a boom year along with Small copper and to a degree Dark Green Fritillary. A good deal of estimating had to be done for the spring species  so  its difficult to comment . Overall things look in good shape.