Brockadale YWT
Pontefract
Site Details:
Recorders: Paul + Joyce Simmons, Les Driffield Distance: 2988m Altitude: 32m Walk Time : 1 hour
Brockadale is located in the valley of the River Went as it flows through a craggy, steep-sided gorge formed after the last ice-age when glacial melt-water burst through the magnesian limestone ridge. Around 350 species of plants grow on the nature reserve. Early flowers such as cowslip, common dog-violet and spring cinquefoil, well suited to the limestone soil, can be seen in spring. Native plants such as rock-rose follow, as well as orchids, salad burnet, yellow-wort, betony, field scabious and, in August, a profusion of clustered bellflower. Butterflies abound in the meadows, with the spectacular Marbled White and Dark Green Fritillary are unmissable in July. Day-flying moths like Six-spot Burnet and Chimney Sweeper are common, Silver washed Fritillary is now a common sight and both Purple and White-letter Hairstreaks can be seen.
Sections:
S1 starts from the car park westwards along the top of the hill with hedgerows as well as the meadow below and has very high counts of meadow brown and is a favourite with the Small Tortoiseshell. S2 is just above the Horse field in the process of being improved with lots of Small Tortoiseshells. We enter the woodland S3 in a very quiet shady section frequented occasionally by Speckled Woods and Silver --washed Fritillary. S4 is a small meadow in the middle of woodland which abounds with violets and is the home of the Dark-green fritillary and many Marbled Whites. S5 known as the the butterfly ride is full lof Speckled Woods and Ringlets and is a favourite with the Silver-washed Fritillary. S6 descends through the woodland towards the valley with more Ringlets and Speckled Woods. Section 7 valley bottom with damper calcareous grassland stands out with huge numbers of Ringlet, Marbled White, Peacocks and the other vanessids plus white but particularly Brimstones and Gatekeeper. Brown argus also appears here asS7 S8 is intermediate scrub before starting back up the slope of S9 and Common Blues appear in number. Holy Blue has been spotted in S10
Results: 2023
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%.
As well as being a dry site of calcareous grasslands it is also a woodland site so overall numbers are dead on the county average of 9% up. The trends are pretty close to the county with teh big winners Brimstone, Holly blue Speckled wood and Gatekeeper. The big looser was Ringlet as everywhere else but more so here. Dark Green fritillary loses are similar to most locations being extremely high and teh species has been lost from its new gains along teh limestone ridge, hopefully it wil bounce back just as quickly . Tortoiseshell still tumbling and showing no signs of stoping one of its worse declines in modern times while Peaock is at last turned teh corner and starting to improve again. Comma increases of 90% seem now to be teh norm as do strong increases in Speckled wood and one is left wondering how much of this is down to loss of Small Tortoiseshell and all its parasites are benefiting both these species. Marbled white had yet anothe good year. As at other woodland site white letter hairstreaks were much more visible as teh descend from their normal tree habitat after the rains washed away the honeydew and could be found nectaring on flowers. Small skipper is very disappointing as many unmanged sites had quite a boom of this species. Many local sites alos saw teh big influx of migrant small white this summer as here. brown Argus on lowland sites liek this showed a very strong increase.
Results: 2022
A better year in 2022 . Small Skipper continues its slow decline as in many sites and is worrying. Large skpper was up on last year in most places by 30% and Brockadale is spot on. Brimstone was also up by a similar amout to teh rest of teh county. green viened white and Orange tip were about teh same which again is similar to the county with just smal changes but Large white in teh county was down 11% and -2 here so fairly similar. It great to see Whiet letter hairstreak spotted on transect which is rare descending only in dire heat or lack of honeydew. In Yorkshire Smal Copper was up a tad on last year but wel down longer term so great to see a good few here although their occurance tends to be sporadic. Brown Argus on rockrose suffered very badly as here but boomed out on mineral soils on cranesbill Common Blue suffered as well more so than other sites possibly due to drought on Brockadale's chalk -5% across the county. Holy Blue was the same as last year which is quite different from other sites where it really boomed on teh spring generation. The vanessids overwintered really well but were the real casualities in the heat and drought. Small Torts across the county were down -56% as here . Peacock did not suffer as badly here as elsewhere but Comma universally boomed doubling in numbers on the summer generation. Dark green=Frits wer a bit down as again was pretyy universal and Silver washed were well up with a boom in teh county and much dispersal yet again. Marbled white boomed but died off very quickly which masked a significant dispersal of thsi species popping up all over grasslands throughout much of the lowland grasslands The other browns also benefited somewhat but Gatekeaper really boomed. Together the browns pushed the year total above last year despite the huge losses in the vanessids which is reflected in many localities