High Brae YWT

Inglebrough 

Northern Brown Argus transect

Details 

Walkers  Terry Whitaker                                           Distance 1632                         Walk Time 55mins                 Altitude 326m

Situated on the east side of Inglebrough in the Ribble Valley just north of Horton in Ribblesdale. In summer, experience a multitude of plants and flowers, with an expanse of yellow rock-rose in June and the rare Alpine bistort, found here in one of its most southerly locations. Brae Pasture includes areas of hay meadow, calcareous grassland, limestone pavement and woodland. The diversity of habitats support a wide range of plants, invertebrates and birds including notable species such as blue moor grass, bird’s-eye primrose, alpine bistort and frog orchid. Sheep and cattle graze from late summer into late autumn after the traditional late summer haycut. 

Sections

S1 from the layby goes to the tree line that runs north south on teh edge of the limestone pavement . S2  and nearby S9 -S11 are in a grassy area just below the pavement and this is where most of teh action takes place .  Meadow Brown, Ringlet and skippers are restricted to the grassy area of S2 and S11 and is also favoured by the Common Blue. The Northern Brown Argus  reside pretty much in S2-S3 and then S9-11. S9 is a favourite with the Small heath . Dark-green Fritillary very much favours S2 and S10 woodland edge 

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%.

A poor year at High Brae down nearly a third in overall numbers. Biggest losers Dark-Green Fritillary was down dramatically in the drought. Other drought sensitive species like Ringlet, Green-viened White, Large Skipper and Small Heath were alos well down  and all were down across teh county. Northern Brown Argus was just a tad down while on many sites it suffered a good deal more. Big Winners here and countywide were Red Admiral and Meadow Brown both having record years. The site continues to decline at quite a speed which is worrying. 

TRANSECT REPORTS

Results 2022

The signs of some recovery continues with a boom in the browns this year  with Small Heath accounting for a good percentage of the improvement with the best year since 2014. 

Both Golden skippers reappeared  with the exceptionally warm weather but drought was a big factor for other species with last years boom in Dark Green Fritallary  crashing. Northern brown Argus held up well  but still in long term decline while Common was at least quite a bit up. . Smal Tortoiseshell crashed as it did throughout Yorkshire due to poor quality nettle and no second generation was possible.  

Results 2021  

From 2014  possibly the best butterfly year by a good margin in recent times there has been a slow decline. However  there is signs this has slowed . When many species were peaking in 2018/19 here many were falling which we might guess is down to drought on very thin soil. 2020-2021 wet summers seemed to suit Northern brown Argus  as it did in 2016-17 which were universally poor fo rmost  butterflies eleswhere and Common Blue and Dar- green Fritillary and Small heath dropped dramatically.