Green
Hammerton
inc. Helenfield LNR
Site Details
Recorders: Alistair Taylor, Angela Taylor, Stella Craven, Teresa Warbrick Distance: 3590m Walk Time : 1hour 15mins
The transect includes Helenfield Nature Reserve, a wet woodland planted about 20 years ago.
Sections:
S1 village lane then becomes farm tracks S2 with many of teh commoner garden species plus Common Blue and Holy Blue . S3 headland yielding really good numbers and a particular favourite of teh Small Tortoisehell. Then into intensive agriculture of S5-8 to reach S9 the edge of the reserve and then back through a woodland ride of S10. After S3 most of the action is in Helenfield NR woodland of section S9, the west edge, and S10 through the wide ride with Whites and Browns being particularly numerous along with Comma Peacock and Red Admiral . The White-letter Hairstreak was seen in S9 woodland edge grasslandand has the highest counts of most species and particularly Gatekeeper. S10 is a favourite with Speckled Wood
2024 Results
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
Green Hammerton did just a whisker better than the county average. Large Skipper , Brimstone and Large White did better than the site average. Speckled wood did proportionally not so bad. Ringlet on regular sites did rather poorl but rather well on dry sites recovering from the drought. Small Tortoiseshell plummeted while Peacock made a dramtic return after last year.
2023 Results
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%.
Green Hammerton had a pretty good up 6% and close to the county average but still a tad down on last year. Species trends follow the county trends fairly closely with the big winners being Gatekeeper and Meadow Brown and big losers Peacock and Small Tortoiseshell. As eleswhere there were record numbers of Brimstone, Holly Blue and Comma. Speclkled wood saw a bit of rise although elsewhere it broke records to its best year ever.. Red Admiral also had its best year since the 1990's and showed strongly on all transects apart from those at the highest altitudes. Great to see Wall clinging on even in this bad year for this species. The site trend is still for steady strong increase in total numbers.
2022 Results
A massive increase in numbers on this developing site with almost all species increasing. The big winners were Gatekeeper and Speckled Wood which universally boomed across Yorkshire . An increase in Gatekeeper of 10 fold in 3 years is remarkable. Common Blue is also benefitting from the improving habitat and Wall Brown has been returned as has Large Skipper. Holly Blue exploded as it has done universally. Bad news is short but Peacock had a very poor year with only a very small summer generation. Unusually Small Tortoiseshell has nearly held its ground against last years boom and is at very high numbers For most of lowland Yorkshire Tortoiseshells crashed and some sites saw none after June which was the same at this site with the second generation basically 'cancelled' as the first generation hibernated immediatly in the heat. Meadow Brown was well down on the last 2 years but held onto average
2021 Results
As with many transect this year sees a big rise in Gatekeeper numbers as the species recovers from drought in early 2020 but all the browns have benefited to make for the best year so far. As elsewhere the Vanessids have had a bad year particularly Comma apart from the Small Tortoiseshell whose boom these last two years continues. The cabbage whites also had a pretty good year. Unfotunately Wall has not returned. Holy Blue was absent and had a disasterous oear as it did elesewhere. Small Skipper has maintained it numbers after a rapid rise in the last two years but Large Skipper remains absent
2020 Results
2020 saw small skipper creeping in in numbers into Helenfield and the near disappearence of Large Skipper. Small White had a good year and Orange Tip were in good numbers again along the lanes and on the woodland edge. Small Copper had a good 2nd brood. Tortoiseshell and Peacock saw a good rise in the maturing woodland and the Browns maintained rising numbers The migrant Painted Lady and Red Admiral had a poor year