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2023 Review
2023 saw the world's weather switching to El Nino, the warming phase, and was the hottest year ever. Peking reaching 52'C and some of the worse forest fires in living memory in Canada and Greece. The very hot dry summer of 2022 was likely to have a big effect on 2023 with drought likely causing heavy mortality of juvenile stages and our expectations for the year were poor. Autumn 22 was likely good for our butterflies with a sharp cold spell in December ensuring caterpilars stayed in hibernation through yet another mild winter. Spring was dominated by cool easterly winds especially April and numbers were already down 8% by the end of May. Holly Blue up near 6 fold after booming last year and Comma up near 3 fold after booming last year along with Speckled Wood contributing the most numbers doubling also after a good year last year. Brimstone also showed a strong Increase. The biggest losers were Small Tortoiseshell and Peacock .
Overall, this was a warm and rather wet summer. The lion's share of fine weather - warm, dry, and settled with high pressure established - occurred during June, which was the Yorkshire's warmest and provisonally 2nd sunniest June only. In contrast, July and August mainly comprised unsettled weather. July in particular was very cool, dull and wet with the jet stream displaced to the south and a succession of low pressure systems . The month included a succession of particularly disappointing wet weekends with low pressure dominating However the most noticeabel differences were between lowland/damp areas up and upland/dry sites down considerably. The 'formative' part of the main butterfly season in May and June were hot and dry (+ 1.5’C) and dry sites like those on the Craven limestones drought really hit plants badly. This came to abrupt halt with July being cool and frequently wet (-0.5’C) again making recording difficult followed by a very average August and very warm Autumn. Although there were equal numbers of winners and losers as you can see from the chart opposite, a boom in the browns numerically pushed overall numbers up 9% and close to our all time record back in 2014.
Losers:
Most of us considered it a very poor summer and certainly our garden buddleia bushes after a grim 2022 attracted even fewer visitors this summer and Peacock and Small Tortoiseshells had a second very poor year. Both these species use nettles in full sun searching out larger clumps with with soft young growth but this year drought and June heatwave and poor numbers overwintering led to further steep decline in both species. In contrast in the cooler uplands they faired better with Peacock showing signs of recovery benefitting somewhat from the July rains. Othe losers were Dark-green Fritillary , Northern Brown Argus, Small Heath, Wall and Dingy skipper all on short grasslands which would have suffered along with moisture sensitive species like Ringlet and Green viened Whites which favour damp areas.
Winners:
The July rains made for perfect conditions for large numbers of arriving Red Admirals from Europe who boomed on the soft young nettle regrowth caused by the rains. It was easy to count dozens of 'clipped' nettle heads on a countryside walk where developing Red Admiral caterpillars bite part way through the nettle stem causing it to fall over on itself allowing the larva to make a larger safe nest. Comma also benefitted chosing nettles in part shade that suffered much less in the June heat and for a second year Comma boomed possibly helped by less parasitation due to decline in other Vanessids species with a bumper hutchinsonii generation.
Out in the countryside, particularly woodland and hedgerows it was also super year for many of our Brown species particularly in the vale of York and river valleys but not on sandy sites . Gatekeeper, Meadow Brown, Marbled White and Speckled Wood enjoyed a second very good year; these species also happening to be largest winners of climate change . Small Skipper with Small Copper also saw a significant increase after a run of poor years.
Monitored sites differences:
Most noticeable was the large differences between moisture retaining soils of the valleys and thin , dry limestone or sandy heaths where there was no shade. A large number of damp grassland, hedgerows and woodland benefited hugely with 3 sites seeing more than 50% increase! Small number of thin chalk and sandy sites suffered Craggy sites like Hawnby Hill down 25% and Whitcliffe also doing poorly
August 2023 : Summer Species Review for June and July
After a very poor spring and a diabolical July we could be forgiven for thinking it couldn't get any worse for our butterflies. Quite the Opposite! June is the critical formative month and this year's heat was highly beneficial for maturing caterpillars and pupa with half our summer species doubling in numbers against previous summers leading to a 37% overall increase, potentially making this a record year. The graphic below illustrates the change in abundance this summer against previous summers and shows the fortunes of species but we can also translate that into insect numbers to illustrate better what we actually see:
Winners
Meadow Brown is always our most numerous species every year, and this summer, numerically, saw the largest increase . It didn't seem to have suffered in last summer’s and this spring’s droughts. The species continues a pattern of increasing abundance in recent years and then by nearly doubling this year. This same pattern also applies to Gatekeeper, Marbled White and Speckled Wood up by about a half this year after a series of good years.
Both the two cabbage white species more than doubled being significantly bolstered by migrants. After a series of poorer years they just seemed to be everywhere, due to their mobility, often you could see ten in a vista which made them the most noticeable and placing them at the top of Yorkshires Big Butterfly count.
Most interestingly species that had done badly for some years made a dramatic comeback particularly Small Skipper, nearly doubling and Small Copper trebling obviously favouring the hot dry conditions. Even the less than Common Blue had a better first brood.
Across Europe these last 2 years of hot summers the migratory Red Admiral has been the biggest winner. Last year it became the top species in southern England but this year they managed to reach the north. It became a familiar and entertaining sight to see them basking in the evening sunshine on house walls soaking up the last rays and letting off steam with their usual antics of high speed chases of rivals in a circuit of the garden. Their size strength and grace with tremendous speed then effortless glide was the highlight of this summer
The Comma’s rise these last few years seems to have become a relentless boom with the hutchinsonii generation this year being exceptional, often making it the second most common butterfly on our Buddleia bushes after Red Admiral. It was also great to see Peacock showing the first signs of recovery after a very poor 2022 their caterpillars likely benefitting from the early July rains
Losers
There is most certainly a pattern amongst the losers of the effects of last summer’s and this spring’s droughts. Ringlet much prefers the damp and although only 20% down in abundance was by far the biggest numerical loser. The 2nd biggest numerical loser was Small Tortoiseshell after two years of booming in warm damp summers collapsed without a second generation last year and continues to struggle this. It prefers soft green new shoots of nettles absent last year but which this July’s rains have provided in abundance so there is hope still for a comeback in the second generation this year. Dark Green Fritillary is showing a precipitous fall to just a fifth of previous again after booming for some years and being lost completely from our sites or down to just a handful of individuals. Something went wrong as it did for this species back in 2016 for reasons unknown. Following the same pattern of drought effects on thinner soils Small Heath and the rockrose form of Brown Argus show large decreases.
Monitored Sites differences
Only 1 of our monitored sites actually showed a decrease and nearly a third doubled their totals across all species. Woodlands showed the largest increases and sandy /dry heathland the least.
Our site data marries quite well with Big Butterfly count remembering that these counts tend to reflect mobile species attracted to our flowering plants in our gardens elevating the big showy colourful Vanessids and highly mobile whites particularly during this year of strong migration while pushing down resident countryside rather immobile stalwarts like Meadow Brown and Ringlets which dominate our summer butterflies. The BBC Yorkshire winner of Small white came second on our sites while the other winners, Large White Red Admiral and Gatekeeper are not far behind.
After a few poor years overall counts are back up to their 2019 high of 12 butterflies per count and 50% up on last year; a massive improvement begging the question even with the very poor weather of July and last year's and this spring's drought that we are heading for a good butterfly year simply because of an exceptional June.
July 2023 : Big Butterfly Count
Big Butterfly Count 2023: Red Admiral is a clear winner
After a few poor years overall counts are back up to their 2019 high of 12 butterflies per count and 50% up on last year; a massive improvement begging the question even with the very poor weather of July and last year's and this spring's drought that we are heading for a good butterfly year simply because of an exceptional June. Many of us have noticed Red Admiral numbers are up again this year after a good 2022 and numbers having been growing steadily braking records and being No1 throughout northern Europe these last 3 hot years.
Yorkshire's counts have been strongly influenced by European migration of all the top three species combined with a hot June increasing local abundance particularly the Large and Small White. The other beneficiary of the hot June were the Meadow Brown but more so the Gatekeeper has had another record year. The main losers in the droughts include Dark-Green Fritillary, Northern Brown Argus and Small Heath
The good news is there are large numbers of Red Admiral caterpillars presently so we can expect a 'feast' of these glorious giants before they start their return trip south. With their ability to find a northerly wind and fly at 2000 feet in near zero temperatures meaning they can do the last leg of their journey home to North Africa in just a few days rather than the slower northern migration at 200 feet over several generations.
June 2023 : Spring Species review
It is widely considered this spring was very bad for our butterflies but was this really the case? Certainly there were very few opportunities to see them due to a very poor April. However, this does not mean that they werent there and we just missed them. This is where our monitored sites tend to reveal the truth because of the very strict rules of only counting in conditions suitable for flight. Results for weeks 1-9 (April and May) from 20 of our monitored sites is summarised below comparing this year with the average of the last two by percent, plus, the number of site showing increases or decreases to give us insight into why. Yes, Numbers were slightly down but there was a good deal of variation with some riverside sites showing large increases like Sprotborough Flash , Fairburn Ings, Pottric Carr, Rodley NR and Thorpe Marsh while some Limestone/Sandy sites, being more susceptable to drought, showed big decreases, for example Fordon, Whitcliffe and Strensall Common. Interestingly overall there were the same number of sites up as down and overall numbers of all species down only 8%. This however was a very mixed bag with some quite extreme winners and losers. Biggest winners were Holly Blue up near 6 fold after booming last year and Comma up near 3 fold after booming last year along with Speckled Wood contributing the most numbers doubling also after a good year last year. Brimstone also showed a strong Increase. The biggest loser is Small Tortoiseshell which has been absent from a significant number of sites since last June after failing to have a second generation in last years extreme heat .Likewise Peacock also suffered but after so few were seen last summer we had a much better show this spring indicating they were forced to hibernate very quickly in last years heat. Small Heath suffered badly with their habitat being dry/limestone sites. Brown Argus, at least on dry rockrose sites, showed a strong decrease while on mineral soils showed an increase; much like last year. Most worrying is the very poor show of Wall; down to a quarter of previous numbers after several good years. We can expect similar variation as the first results of the summer species start to come in with many of the Browns booming while the Dark Green Fritillary being wiped out of some of its sites with reduced numbers.
More to come in the summer review in Early August
May 2023
27th May As the June dip commences and thespring species decline there are already intriguing signs of a bonanza in some of our grassland species particularly moths. Large numbers of Mother Shipton, Burnet Companion, Small Yellow Underwings and even small Purple and Gold (mint Moth) are being seen on our monitored sites. Dingy Skipper on its lowland sites is in good numbers but on the wolds it is very poor so we can conclude dry sites suffered more in last years heat. Small Heath numbers are building as are Common Blue. The spring whites are now in rapid decline while Holly Blues and Brimstones are still a common sight and just an occasional very elderly Peacock
The first Large Skipper was spotted on the Fordon Chalk Bank transect this week (23rd May photo thanks to Kerry Metcalfe) which is earlier than the average so it looks like the current run of sunny warm weather is leading to a catch up .
Large Skipper is the first of our summer species to emerge. Due this week is also Large Heath, Meadow Brown and Smal Pearls and Derbyshire has already seen Dark-green Fritillary and new generation Small Tortoiseshells.
September 2022 Highlights:
Picture of the Month
Wall at South Gare, Redcar photo by Andy Symes on 23rd September
A 3rd generation of Wall emerged mid month all along the Yorkshire coastline
September sightings have been generally poor although Speckled Wood have had a good showing as have Small White along with reasonable numbers of third brood Small Copper and Brown Argus. So far no signs of third brood Wall or Holly Blue although just south of us they are showing in small numbers. Very low numbers of Brimstone and Peacock continue while there are still quite a few Red Admiral and Comma feeding on rotting fruit and Ivy flower. Amongst our Moths there have been Clifden Nonpariel, Convolvulus Hawk with yet more Humming Bird Hawk moths; a bumper year for migrants.
After several cool nights and days the weather has certainly turned more autumnal and my expectations were low walking Bishop Wood this week. However it could have been late June with the sheer number of Comma's on Blackberry with 15 individuals counted on the transect. Comma returns to our woodlands to hibernate and 'gorge' on rotting fruit, getting ready to go into hibernation after their summer aestivation. Into view came something considerably larger and to my surprise it was a female Silver-washed Fritillary. It made straight to the orange binding on my notebook and landed; i've had this happen before; they are very strongly attracted to anything orange as part of their gregarious nature. It rested for a few seconds as if to say 'Goodbye old friend' before zooming off. The last Silver-washed Fritillaries were seen in Yorkshire in Mid-August and the one opposite shows the kind of condition they can get into by this time. My specimen condition was not too bad which suggests it had aestivated from sometime back in the heatwave of July. The european Cardinal and the american Great Spangled Fritillary the females only will aestivate in the hottest part of summer and then reappear 4-6 weeks later after the heat has passes to give themselves more time to find suitable egg laying sites. I suspect amongst the large population in Bishop Wood this individual managed similar but as far I'm aware this is a first for the UK. You can imagine that the same urge to come out of aestivation that caused the Comma's to awake also woke the Fritillary. Most worrying no Brimstones were seen while in a normal year you would see a dozen or more in Bishop Wood.
August Highlights: Another heatwave brings an abrupt early end to the main flight season .
A record year for 'Hummers' and other migrants but second generation species were small in number and duration as the drought continues to severely limit plant growth.
Picture of the Month
Clouded Yellow at Orgreave Common Lagoons, Rotherham Photo by Mike Smethurst on August 28th
After the extremes of the July heatwave and a short reprieve and a little rain at the end of the July, August commenced with mixed weather. For those lucky enough to get the rain plantlife began to revive and there was hope the eggs of grassland species would be saved. The first half of the month was dominated by high pressure and the heatwave returned with temperatures well up into the 30's peaking on 12-13th. As we entered the third week of the month the high pressure moved away to be replaced by showers and some torrential thunderstorms did bring some very welcome, if patchy, rain. The drought continued for most and on the 28th Yorkshire had its first hosepipe ban since 1996. Over the month the Met office reported Yorkshire was 2.7'C above the long term average while southern and eastern areas of UK were 4'C up. Rainfall was a worrying 48%. The first half of the month was particularly sunny was 143% of average.
Hummingbird Hawk Moth is having a record breaking year and most of us have seen one with both Buddleia and Red Valerian proving the best attractant. Good numbers of Red Admirals and Whites arrived in waves throughout the month along with a few Painted Lady and a smattering of Clouded Yellow's.
After the extremes of the July heatwave and a short reprieve and a little rain at the end of the July, August commenced with mixed weather. For those lucky enough to get the rain plantlife began to revive and there was hope the eggs of grassland species would be saved. The first half of the month was dominated by high pressure and the heatwave returned with temperatures well up into the 30's peaking on 12-13th. As we entered the third week of the month the high pressure moved away to be replaced by showers and some torrential thunderstorms did bring some very welcome, if patchy, rain. The drought continued for most and on the 28th Yorkshire had its first hosepipe ban since 1996. Over the month the Met office reported Yorkshire was 2.7'C above the long term average while southern and eastern areas of UK were 4'C up. Rainfall was a worrying 48%. The first half of the month was particularly sunny was 143% of average.
Hummingbird Hawk Moth is having a record breaking year and most of us have seen one with both Buddleia and Red Valerian proving the best attractant. Good numbers of Red Admirals and Whites arrived in waves throughout the month along with a few Painted Lady and a smattering of Clouded Yellow's.
16th August Update
After that late July 'bit of rain' which revived our grasslands at least away from south and east of the county the heatwave of the last week has scorched things once more making us worry again about the survival of 2023's butterflies. It shouldn't be too bad now the heatwave has broken down. The good news is also Common Blue are back strongly with their second generation which is the first positive for this species for several years. A few females Gatekeeper and Meadow Browns are still flying along with low numbers of ragged Small Skippers plus a few fresh Small Copper and fair numbers of next generation Small Heath. Wall is currently on the wing and has surprised quite a few people with its spread reaching places where it has not been seen for some time but dry sites are suffering in the drought but it going to be a good year for this species. Whites, particularly Large White, continue to fly in quite good numbers but still our Buddleia bushes remain pretty quiet with only Red Admiral making up the vanessids, very, very low numbers of Peacock and although the second generation Small Tortoiseshell are now flying numbers are still very very low.
July Highlights : A Gatekeeper boom and answering ' Why has my Buddleia bush had so few Butterflies?
Picture of the Month
Silver-washed Fritillary by Peter Stoppard at Lindrick Common
Silver washed has seen a significant dispersal in Yorkshire pooping up in gardens just about anywhere as it did in 2019
July was dominated by high pressure to the south of us drawing in warm continental air. While an almost continuous stream of fronts, often with heavy showers, dominated across the north and west side of the county. As you can see in the July rainfall map below it split the county in two along a line approximately from Wakefield to Malton. Below the line had record low rainfall at only 25% of normal while above was much closer to normal rainfall. This was very clear as you drove into South Yorkshire as verges and lawns were scorched brown. But to north by the month end the grass was making a strong recovery and there is a good deal more hope for next years butterflies!
The high pressure did briefly move over top of us creating the heatwave from 16-20th and Yorkshire had its hottest day ever on the 19th at near 40'C. Temperatures were 2'C higher than average for the month. The extreme heat was in large part due to already very hot air over France coming up and then getting superheated under the high pressure acting like a pressure cooker. The last week of the month was often very dull and drizzly making even finding a transect walking slot difficult.
As the heatwave struck transect counts were already beginning to fall away but the heatwave shortened their remaining lives and numbers fell dramatically especially the Skippers, Marbled Whites and Ringlets with only Gatekeeper surviving in any numbers by the end of the month and having a outstanding year with numbers near three times 2021. Now we are left with a bit of gap! Peacocks are still emerging but are quickly going into hibernation and the big peak in Comma is now subsiding and Tortoiseshell numbers are very low leaving our buddleia only with a few fresh Red Admirals. The next generation tortoiseshells are presently pupa and fingers crossed we wil get a good emergence in August. Meadow Browns are still flying but the heatwave has reduced their number.
Summer 2022 Sneak Peak at our Monitored Sites
The summer highlights has to be a very strong summer generation of Comma with numbers up nearly 4 fold. In contrast Small Tortoiseshell after a disastrous spring has a equally disasterous summer with numbers nearly halved and we suspect this is the bust after the last two years of boom due to the tachinid parasite Sturmia bella. The figures for Peacock are slightly misleading as last year they had barely started but this year are already past their peak and seem to have suffered but the next few weeks will tell us if 2023 will be a all time low. It dificult to believe in 2020 on one section on my transect I had 145 and last week just 3. So, it looks like parasitation and the main peak being early is the reason our Buddleia bushes have been pretty empty through July although Red Admiral has been bolstered by migrants and numbers have been up near 3 fold. The good weather has had a positive influence on many species with both Large + Small Skippers up after two years of down. The Large + Small White also show a recovery after a not so good 2021. The other highlight are Gatekeeper has nearly trebled and by the end of the month is just keeping our interest alive during the Big Butterfly Count where there has been not much else to count and interest in the scheme has fallen substantially as a result. Small Heath after a bumper year in 2021 is doing an adjustment and returned to more normal levels; down 40% but still good. The damp loving Ringlet and Speckled Wood bot had a great summer despite the drought and really benefitted from the late May downpour. Silver washed fritillary although down in Bishop Wood this year due to the large amount of forestry work last winter is still above previous years and there has been a big dispersal again through the county with insects popping up almost anywhere, returning to woods where it was last seen in 2019. Holy Blue continues to do well although the peak is still to come. In shear numbers it is always Meadow Brown that determines the overall summer count and its good to say it has not suffered too bad in the drought and numbers are slightly up consistantly across the county. Marbled White we thought were booming went over very quickly but even so was fairly consistantly doubled in numbers. Dark-green Fritillary after an extrememly good year last year is down this as were Brown and Northern Brown Argus. It remains very worrying that Common Blue shows no come back.
'Sneak peak' takes a subest of our 70 plus monitored sites for which we have regularly input data and complete enough for us to analyse. Thank you all those who contribute.
29th July. A dull damp week but will it save 2023's butterflies? The south and east of england are still experiencing extreme drought and we are lucky we entered the year with full reservoirs or we would already be on hosepipe bans or worse. Our summer species have already laid most of 2023 eggs but what will those larvae find when they hatch in a week or so time? Those who remember 1977 know back then the heatwave continued till the last days of August and it was too late and a massive crash in lepidoptera populations resulted. Similarly in 1995 although the weather broke in mid August. We are also lucky we had those couple of inches of rain in late May which the south didnt and this pattern continues. If the plants in our hedgerows and grassalnds begin to recover then there is hope the effects will not be long term. For many of our scarcer species 1977 was the end of the line and they went extinct in close to 75% of sites and never returned. Species like Green-viened White, Ringlet and Speckled Wood are the most sensitive to dry conditions. More on the BC Blog HERE
July 26th UPDATE
Phew!! What a scorcher! Just as our summer species hit their zenith the heatwave struck on the 18th when I expect most of us retreated inside well before midday. The peak in numbers has been significantly higher than 2021 but the peak flight periods are earlier and shorter in duration. Gatekeeper in particular has had a good summer and is peaking this week while Ringlet , Marbled White and Meadow Brown are starting to decline quickly. The heatwave has certainly shortened lifespans significantly. A big disappointment is the Parkgate, Sheffield Grayling have not been seen this year. The continuing drought plus the extreme heat has forced both Purple and White-letter Hairstreaks to the ground looking for moisture and cool but at least making them much easier for us to observe; often in numbers and behaving lethargically below nearby Elms and Oaks. There is nothing more graceful to watch than Silver-washed Fritillary which is presently at its peak and has returned to a number of locations where it was last seen in the big peak in 2019 and even East Yorkshire suggesting another dispersal event. Numbers on our monitored sites are up again and it is easy to see 50 plus individuals on a walk through Bishop Wood, Selby see our Butterfly Walk HERE . They are a true delight to watch gliding and soaring through the woodland rides, and, getting harried by the occasional Comma who are also having a very good summer with a very large increase in numbers on our transects. A few elderly Small Tortoiseshells are still on the wing, but very patchy, and the most worrying is the distinct lack of Peacock. Low numbers have been seen but have quickly gone into hibernation leaving our buddleia bushes almost empty apart from the occasional Red Admiral, often very fresh second generation. Tortoiseshell caterpillar I raised have only produced tachinid parasitic fly so maybe we are seeing a boom in their parasite after the last two boom years for the butterfly. In contrast Comma with different generational timing and after being in steep decline these last two years is having a great year. So you can assume Comma have dodged the tachinid flies who only have a adult life of 2-4 days, and, more closely tuned to the Tortoiseshell life cycle. Tachinids are large and closely resembles a house fly and lays minute hardened eggs individually on nettle leaves around feeding caterpillars who then ingest them. Infected caterpillar pupate normally and can even reach the wing colouring up stage before killing and the crysalis. The flies larva continue to feed inside for a few more days and then emerge from the pupa and abseil to the ground via a long white protein thread which is a give away sign if you ever find a pupa or rear them yourself. The fly larva pupate within a few hours into a chesnut brown oval pupa. A long gap of nearly 4 weeks before they emerge in order to be on the wing as the butterfly larvae reach the 4th instar which is about now on my local nettle patch. The recent boom/bust cycle of our vanessids is likely caused by tachinid Sturmia bella . This species arrived from Europe in 1998 from the continent and is now dominant and has been contraversially linked to the recent decline in numbers of our vanessid species although there is no evidence this is anything other than natural variation although the ups and downs now seem to be much larger!
The first 'wild' Purple Emperor for many years was seen in a garden at Oughtibridge, Sheffield this last week. In modern times there has been very few observations of this species known for its ability to stay hidden from human view, rarely coming down from its lofty treetop home. A female decended into a garden and stayed some minutes sufficient for a very accurate description by two witnesses and verified by Dennis Dell who is local to the area. The garden backs onto Beeley woods part of a complex of woods refered to as Greno and is of ancient origin. These woods containing many oak and at 700 ha. are the largest in Yorkshire. Not only is the habitat correct the date also indicates extrememly strongly this specimen is of natural origin with this sighting corresponding to the emergence of females in Sherwood forest this year where they are having a bumper year much like the rest of the country. The question is; is this a wanderer or does it indicate local breeding? Purple Emperor is one of our fastest spreading species with much increased abundance nationally with Nottinghamshire having some of the strongest colonies. It was tantalising to discover South Yorkshire only had one previous sighting by an air-raid lookout at Ewden head in 1941 during the Sheffield blitz and is just 6km away. You might suspect that a lookout would have high power binoculars to hand. Across this species range, there are many cases where it has existed at extremely low population densities completely un-noticed until someone who knows where and how to look with binoculars has rediscovered it. Could this be true once again?
Now the species has fully emerged grounded insects are rare and much of the activity is likely to be on prominent highspot trees after midday. Only the Scotch Argus has not emerged but is well overdue at its Wharfedale locations.
There will be a more detailed analysis of the summer so far before the end of the month with a 'Sneak Peak' of Summer 2022 from our monitored sites
JULY 11th UPDATE
Many of our species this week are starting their second generations, including Small, Large and Green-viened Whites, Common Blue, Small Copper and Holly Blue are rapidly building in numbers. Peacock and Brimstone are also just beginning. Meanwhile most of our summer species are at their peak with counts on our tramsects commonly between 200-500 individuals. It is looking like a good summer as the heatwave begins, but concern grows whether the current draught and withering plants will significantly adversely affect mortality.
June Highlights : A month of beautiful migrants and a Marbled White boom
Hummingbird Hawk Moth by Chris Cox taken in his garden in Keyingham
Always a delight and one of many seen throughout Yorkshire as they migrate
June was another dry month and quite changeable despite a couple of brief hot and sunny spells mid month after a very poor start . This weather pattern has certainly affected both butterfly numbers and the erratic emergence of new species during the month after the cold Jubilee week. Certainly the highlight is the contining migration of Hummingbrird Hawk moths along with Painted Ladies a good many Red Admirals and Silver Y moths. Transect numbers have been doubling almost every week since the low point of the June lull in the first week of the month. The 2nd week of July they wil hit their peak.
Speckled Wood's came out in large numbers in the middle of the month while Common Blue and Small Heath 1st broods continue to decline. The Whites were almost absent from many transects but in the final days of the months second brood commenced. Small Tortoiseshell have slowly increased through the month but not on the scale of last year.
The summer brood Comma (Hutchinsoni) has appeared very strong on our monitored sites with nearly three times the numbers of last year. It is looking promising for a recovery after some poor years recently.
On our main monitored sites on the Wolds and the Limestone ridge Marbled White is showing a very strong increase by a factor of nearly 3 see the flight charts. This comes after a very strong showing last year. A similar thing is happening to Meadow Brown and Ringlet with number up by a factor of 2-3 so far.
30th June Update Migrant Hummingbird Hawk Moths still being seen in good numbers along with Red Admirals. There are the first signs of a new hatch of Small Whites and a few Green-viened White along with large numbers of the 'Browns' and Small Skipper now emerging Marbled White explosion? After finding a Marbled White on my tiny home meadow in Cawood I looked at the latest transect results and numbers this year are currently running 2-3 times higher than last year. It is likely we are seeing a good deal of dispersal of this beautiful butterfly so please do keep an eye out and send your reports. It is difficult to believe the Vale of York is being invaded after a good year last year!
26th June Update A larger influx of Painted Ladies but particularly Red Admirals today. The 'grey pilrims' (Painted Ladies), as often as not, are seen flying fast in a northerly direction. The much warmer weather has led to the emergence of Gatekeeper on the 23rd 4 days later than averge along with Silver-washed fritillary, our earliest ever emergence at Brockadale . Purple Hairstreak emerged on the 24th spot on schedule. Essex Skipper is the last species to emerge and it is likely already on the wing so please do look out.
June 22nd UPDATE Another influx of Migrants. Lots of reports of Hummingbird Hawk moths in your gardens is causing some excitement and what a sight they are! In addition we still having a fair influx of Painted Ladies and Red Admirals.
In the last few days Graylings have been seen at South Gare somewhat early and White-letter hairstreak has emerged more than a week later than average; the year remains very mixed up! Certainly the current very warm weather wil speed things up and already the transect counts are trebling as the season reaches its climax. Good numbers of Large Heath are now on the wing after a slow start this year held back by the cool jubilee period. If you wish to see them then I recommend Crowle Moors Butterfly Walk HERE. The Purple Emperor in Sherwood forest are pupating fast now and predicted to be on the wing the first few days of July. They are making a good showing in the south .
Spring 2022 Review
Spring 2022 has been rather warmer, dryer and sunnier than average according to the Met Office for Yorkshire. May temperatures were close to normal but heavy cloud depressed sunshine hours by more than 20%; particularly in the north and west of the county while East Yorkshire was average. May has been dominated by a succession of atlantic fronts then a nice pulse of warm winds from the south that brought the mini invasion of migrants which are still with us into June. The end of the month into June was cool.
The season was running early till the end of April but then things have slowed quite dramtically in May with the majority of species now emerging behind schedule. The last week of May, crucial for timing of our summer species, was very cool and we suspect both pupal and late instar caterpillar development has slowed or even stopped which means the June lull is likely to be longer and last till the 3rd week of June.
Looking at your casual records (see the pie chart) Holy Blue sightings have nearly tripled on this time last year as have Red Admiral and Duke of Burgundy, while Comma and Speckled Wood have doubled. Small Tortoiseshell and Peacock are slightly up compared to this time last year. Losers seem to be Brimstone, Orange Tip and Green Hairstreak slightly down. Small White has doubled while Green-viened White is slightly up Large White is well down.
For a truer picture of our species your best looking at the trends from our site monitoring with transects. Opposite is an early 'Sneak Peak'. Taken from 20 of Yorkshire's monitored sites we have results up till 1st week of June. The comparison is with 2021 and, overall, numbers are about the same, even with the way better weather of 2022. Most spectacular is Holy Blue which sees a 22 fold increase in abundance and from being present on just 1 site last year has returned to 10. The fall in numbers over the last 2 years, confirms we are now in the 'up' part of this insect's cycle with its parasite. Almost as spectacular is Red Admiral recording 9 times more abundant after the wave of migrants in May. It was almost entirely absent last spring. The contrasting and consistent story across most sites is the decline in Small Tortoiseshell and Peacock by approximately half. Peacock abounded in 2020 giving good numbers coming from hibernation last Spring but they fared very badly in reproducing in the very poor weather, so lower numbers went into hibernation last autumn. Amongst the whites, Small White shows a strong increase, and Brimstone has done better. Speckled Wood have also done quite well. Wall, Common Blue, Small Heath and Brown Argus have peaked earlier in the better weather this year and account for most of the improvement at this point in time.
May 2022 Highlights : Lack of sun slows things and a mini invasion of Painted Ladies
May: Picture of the Month
Painted Lady by Chris Cox
28th May Migration Update; Many different migrant species are arriving into the UK in a mini invasion including Red Admiral, Silver Y , Striped Hawk moth and of course, Painted Lady. Some are looking surprising fresh considering their long journey. Painted Ladies proved to be the most numerous butterfly on the 3 Hagges transect this afternoon with 3 recorded but the winds are just about to switch around to the north.
22nd May Migration Update; Many different migrant species are arriving into the UK in a mini invasion including Red Admiral, Silver Y , Striped Hawk moth and, of course, Painted Lady. Some are looking surprising fresh considering their long journey. Cutting the hedge this morning in my Selby garden I saw 2 Painted Ladies and a Red Admiral and a few whites. Painted Ladies are tending to follow river valleys and then hill topping ; as is their habit.
15th May Update Although butterfly numbers are just beginning to drop on the transects as we approach the June dip it has been a very good Holly Blue year and pretty good for Orange Tip as illustrated by this Dutch graphic of the 2022 flight curve. The dry conditions however will slightly impact our summer species numbers. Currently there is a large wave of Painted Ladies on the south coast so we may expect to see a few with the current good weather from the south.
April 2022 Highlights The season starts early with good numbers
Picture of the Month
Small Tortoiseshell by Tony Chapman
It has been a good start to the season being not only early but numbers good, partcularly Small Tortoiseshell and in the last week Holly Blue appears to be having a bit of a boom after the duldrums of the last couple of years. The month started cool and our transects walkers have found it difficult to reach minimum weather conditions to survey and most have dropped 1 or 2 weeks through the month. However just like 2021 it has been very sunny and dry . A short warmer spell mid month that saw Dingy Skipper appear extremely early at Fordon Chalk banks and then the winds switched back to the cool northerly and slowed emergence. At the very end of the month a short spell of warm southerleys brought out Duke of Burgundy, Brown Argus, Wall and Small Heath on the last day of the month. Again many of these are earlier than normal with the largely very mild Autumn and Winter responsible.
14th April Update
The 2022 season is running significantly early.
Green Hairstreak reported earlier this week on Commondale 4 days earlier than 2021. A Painted Lady was seen on Townclose Hills Transect Kippax today by Rachel Inhestor no doubt born by the warm southerly airflow . Dingy Skipper was also reported today on The Fordon Chalk bank transect by Kerry Metcalfe , 8 dayes earlier than last year and our earliest ever first sighting for that species by 5 days this site yielding the earliest sightings 3 years out of the last 4. This would suggest the first Duke of Burgundy wil be out within a few days with the current run of warm weather and we can expect Pearl Bordered Fritillary a day or so later.
4th March 2022 Update
The 2022 season has started rather slowly
January: There were a few sighting in the warm spell at new year with three of Small Tortoiseshells and a Peacock and then a scatter more on sunny days including another Peacock and a Comma and a couple of Red Admirals
February started with a cold spell and nothing was seen for 3 weeks! Then a Brimstone appeared In Cottingham on the 23rd followed by a number of Small Tortoiseshells and a Peacock across the county plus a Comma in Baildon
March has started with just a single Tortoiseshell recorded so far in Yorkshire
Totals for the year so far are: 14 Small Tortoiseshells 2 Comma, 3 Peacock, 3 Red admiral and 1 brimstone
Big Butterfly Count 2021 : Update
BC have published and overview of the Big Butterfly Count HERE shows despite record participation in this very popular citizen science project individual insect count per record were the lowest recorded in its 12 year history. The average count in 2021 was down to 9 while in 2020 it was 11 and 2019 16. It discusses how much of this was due to weather in the recording period, and of course the diabolic effects of this year cold wet spring compared to recent warm dry springs of 2018-20. The very weak Jetstream this year has a lot to answer for but will it continue? The overwhelming effects were on double brooded species which will likely take a further year to recover. Highlights were Small Tortoiseshell remains poor although we buck this trend in Yorkshire with a boom. Red admiral had a good year in the south but Peacock had its worst year since 2012 and this certainly true in Yorkshire. The 3 week time slot of BBC and the delay in the second broods are really the take away story with some of grassland species actually having a good year and some species enjoying the damp.
September 2021 highlights : A very warm month but numbers still lag
Photo of the month By Chris Cox
The season has ended suddenly with numbers tumbling on our transect walks in the last week of the month, despite the good weather. The only significant nectar presently is Ivy , however our gardens are oasis with Sedums and Michaelmas Daisy drawing in Red Admiral and sometimes Comma. September temperatures have been well over average by near 3'C after the mid month mini heatwave hitting 27'C and more September records being broken! It has been quite sunny as well as dry but counts on our transects have often been single figures from mid month and rather disappointing overall. However, the Whites did have a better month and numbers have recovered well in the second generation. The Small Tortoiseshell boom continues and have often been the most abundant species in our gardens along with Small White. The main beneficiary of August damp has been Speckled Wood on its third generation reflecting the lush grass growth throughout August with counts on woodland transects having been large. It has earned its place as Butterfly of the month. There has been a small peak with the second generation Comma later in the month while Peacock has been mostly disappointing. A third generation of Small Copper was also evident in the middle of the month. Good numbers of migrant moths have been seen in the middle of the month. Quite a few moth traps yielded the rare migrant Clifdon NonPariel (Blue Underwing) and even Striped Hawk Moth plus a Camberwell Beauty was spotted at Scarborough Mere. This is the last update of 2021 and we would like to thank all of you for your contributions with 300 records in September and 3000 so far this season. We ask our transect walkers to complete entering their data so we can bring you a timely analysis of 2021 soon. Please do keep entering your sightings.
SSeptember 28th Update The season has ended suddenly with numbers tumbling on our transect walks in the last week of the month, despite the good weather. The only significant nectar presently is Ivy , however our gardens are oasis with Sedums and Michaelmas Daisy drawing in Red Admiral and sometimes Comma. September temperatures have been well over average by near 3'C after the mid month mini heatwave hitting 27'C and more September records being broken! It has been quite sunny as well as dry but counts on our transects have often been single figures from mid month and rather disappointing overall. However, the Whites did have a better month and numbers have recovered well in the second generation. The Small Tortoiseshell boom continues and have often been the most abundant species in our gardens along with Small White. The main beneficiary of August damp has been Speckled Wood on its third generation reflecting the lush grass growth throughout August with counts on woodland transects having been large. It has earned its place as Butterfly of the month. There has been a small peak with the second generation Comma later in the month while Peacock has been mostly disappointing. A third generation of Small Copper was also evident in the middle of the month. Good numbers of migrant moths have been seen in the middle of the month. Quite a few moth traps yielded the rare migrant Clifdon NonPariel (Blue Underwing) and even Stripped Hawk Moth plus a Camberwell Beauty was spotted at Scarborough Mere. This is the last update of 2021 and we would like to thank all of you for your contributions with 300 records in September and 3000 so far this season. We ask our transect walkers to complete entering their data so we can bring you a timely analysis of 2021 soon. Please do keep entering your sightings.
Big Butterfly Count 2021: The Results are in!
Well done Yorkshire for managing 8600 Big Butterfly Counts this year up by over 5% over last year with 143,000 nationally. Helped by the July heatwave we recorded just over 67,000 individuals or 7.5 butterflies per count compared to 9.2 nationally. 1500 records came in from the Sheffield and Rotherham area, 930 from Bradford, 840 from Leeds, 700 from York, 540 from Doncaster, 520 from Hull and 500 from Harrogate, Thank you all that took part. Three quarters of the records came in over the first 10 days which was the heatwave tapering off as the rains set in the last 10 days of the count. Our Top 5 species were Small White (14.2K) then Large White (13.1K) Meadow Brown (7.1K) , Ringlet (5.8K) and Small Tortoiseshell (4.2K). Nationally the top 3 were same but Yorkshire contrasted with the national results where Gatekeeper came fourth and Red Admiral 5th both; having exceptional years. See more HERE
Photo by Gavin Ashworth at Ribblehead on 12th August
August Highlights: The Tortoiseshell boom continues
Picture of the Month
Photo by Martin Roberts on 25th August at Huntington, York
As the end of the season approaches, a question I've been asked is "Did we have a summer?" Its easy to forget the July heatwave and while in Europe it continued well into August with some of the highest temperatures ever experienced, and devastating wildfires, our heatwave broke up in late July to a procession of rainy days and sunny intervals. August had average temperatures but has been, in large part, cloudy with mists and drizzle and any sun quickly extinguished with convective cloud bubbling up in minutes. Good sunny spells have been days apart and opportunities have been scarce to get out and explore and our transect walkers have struggled to find a suitable 'slot' to walk in, although the north of the county it has been significantly sunnier A blocking high pressure just west of Scotland established in the last 2 weeks drawing down cool NW winds from Scandinavia and the forecast into September is to remain dry but murky.
The August highlight has to be the continuing boom of Small Tortoiseshell's which in our fields and gardens is our most abundant butterfly even beating the whites. On August 7th in a local field with a broad flowering stewardship belt I noticed webbing, and, on closer inspection, the cause was large numbers of Small Tortoiseshell caterpillar webs. Over the next few days what must have been thousands of hungry mouths marched the full length of the field stripping every nettle back to a stump. Now they are emerging and Tortoiseshells numbers have boomed in the last few days with wide scale reports of huge numbers On my Buddleia they was certainly no 'social distancing'!
In contrast Peacock and Comma numbers remain low possibly because of the cold spring. You can speculate that weather conditions were not conducive to egg laying and by the time they were there, later in June, there were few surviving females. In fact Peacock webs were not seen until well into July, many weeks late, and adult emergence has been late, poor and extended. Red Admiral certainly shone as having a boom year on the Big Butterfly Count but only in the south of England however some made their way to Yorkshire supplementing earlier arrivals offspring and good numbers have been seen towards the end of the month.
Early August also saw a very large peak in Gatekeeper after a very good July for the brown family but by the third week they were about finished along with the Skippers. In contrast Meadow Brown continue with fresh specimens being reported till the end of the month . The woodland Hairstreaks survived well past the middle of the month and it was nice to see Holy Blue in good numbers mid month. Small Copper numbers also grew through the month and second generation Common Blue presently. The Scotch Argus was plentiful in its Wharfedale locations and was on the wing throughout the month. The migratory lowland Brown Argus are presently being seen on their second generation but as is usual with this sub species its hit and miss whether you see it. Wall did well in its normal haunts along the coast and uplands but was also seen in low numbers well distributed across the lowlands. Silver-washed Fritillary might just make it into to September and has had a stunning season being the most abundant butterfly In Bishop Wood for the last five weeks. Brimstone are settling into their woodland hibernation quarters where numbers are quite good feeding up on nectar nearby. Red Admirals and Painted Ladies will now start heading off on their homeward journeys gathering on the coast. Individuals will travel 100km a day but on this leg of their migration they are travelling at height waiting for the upper air streams to be south before commencing their perilous journey. Twice as many will leave than arrived originally.
August 13th UPDATE While many parts of Europe are recording some of their highest temperatures ever experienced, and devastating wildfires rage the UK sits largely under cool and cloudy Jetstream with an occasional high pressures systems creating a few dry days, but mostly its been very showery. Out in the fields spring sown crops are late but are gradually being harvested. Crop yields are good where they avoided the worst floods and the seasonal vagaries but overall its an average farming year. Plant growth has been abundant this summer and we have all had to cut our lawn very much more frequently. This has had a knock on in the abundance of most of our species and although our memory will always be of the 2021 as the spring with no butterflies, high summer has certainly redeemed itself . The Whites and Browns have been abundant with Small White now catching up. Gatekeepers are having a particularly abundant year and are maintained their numbers presently. There has certainly been a influx of Red Admirals reflected in the Big Butterfly count but Peacocks still lag well behind as do Comma and we are currently in a dip waiting the next generation of Tortoiseshells. Small Copper are now emerging in numbers and Holy Blue in large numbers and is at a peak. Second generation Wall are appearing presently in pleasing numbers. Scotch Argus still showing in Wharfedale. White-letter and Purple Hairstreak remain strong. Today, just 10 miles over the border in Derbyshire the first Brown Hairstreak was seen at Pleasley Pit transect, Mansfield where it has been present in good numbers for a few years now.
August 4th UPDATE As we pass the peak of the season with cooler showery weather prevailing this last week we have had some record counts form our transects. Meadow Brown numbers are past their peak but remain good and we have had a surge in Gatekeeper which are currently at their peak. The Whites are also at long last getting going with Large White leading the charge and Green-veined now emerging in good numbers, giving more hope that our species are making up for so much lost ground this spring. Only the Small white remains in the doldrums. Brimstones are emerging in numbers now and transect counts are rising. Silver-washed Fritillary is being reported from gardens more and more and is having a good year returning to places where it was seen for the very first time in 2019 and numbers remain at a record high in Bishop Wood. I've even had a report from a York man holidaying on the Scottish west coast that he had seen one there after seeing his very first in Bishop Wood a few days before. The Vanessids are at long last showing signs of getting going these last week with Peacock numbers rising fast and should continue to do so for at least another 2 weeks in an extended season because of the late start. Comma and Red Admirals are also having an emergence plus a few fresh Painted Ladies are being seen. Small Skipper have gone past their peak but Essex Skipper is about at its peak currently. Ringlet, Marbled Whites and Dark-green Fritillary are declining quite quickly. Speckled Wood are at a low although we can expect the next generation very soon in our woodlands . The next generation Common Blue on the lowlands are gathering numbers as are 2nd generation Small Copper and Brown Argus . Small Tortoiseshell numbers are falling as we await the next generation which should build up over the next fortnight. Holy Blue is approaching its peak presently. White-letter Hairstreak are just past their peak but Purple Hairstreak is still strong. If you have a large Oak tree near you, even stood on its own, stand underneath it between 5.30-7pm and watch on the lea side ( they hate wind) and count how many you see and pop it on our sighting page ; dedicated recorders are finding remarkable numbers of this much under recorded species.
July Highlights
Picture of the Month
Silver-washed Fritillary by Ian Brookes Pickering Woods 17th July
The heat wave reverses the fortunes of our summer species
Despite being one of the 5 warmest July's on record with the mid-month heatwave peaking near 30'C it was also wet. Rain was very local with some parts suffering flash floods, mighty thunderstorms and huge hailstones, others nothing . Global weather continues to be driven by weak and undulating Jetstream bringing heatwaves and floods in equal measure. It caused not only our heatwave but also that of the Western U.S, Middle East and China with sweltering temperatures. Northern Ireland had three record breaking hottest ever days in a row and Death valley recording the highest ever recorded temperature on earth of 54.4'C. At the same time the Jetstream dragged warm moist air up from the tropics as very slow moving fronts causing catastrophic rain events in the low countries, China and New Zealand. It was July 14th when the Jetstream moved north and a large high pressure anchored itself over top of the UK. This gave us the the heatwave which lasted over 10 days with our busiest day ever on our casual sightings page on Friday 16th as the mercury climbed above 25'C. The following days were some the hottest of the summer and actually drove some of our casual recorders inside!! even so we had welll over 700 sightings in July and nearly 3000 so far this year.
July: Winners and Losers
Our stoic transect walkers carried on regardless with counts recovering back to near normal during the first week of July . The hot weather coincided with the main emergence of many of our brown family leading to very high scores of Meadow Brown, 40% over last year, with over 1000 recorded on the Thorpe Marsh transect. Over a 1000 Ringlets were recorded on Forest of Flowers, York again 40% above last year It also rapidly turned into a 'Gatekeeper' Summer with more than double last years counts. Other species in July showing big gains were Small Heath at an amazing 260% over 2020. Speckled Wood were also double last year while Silver-washed Fritillary at its stronghold in Selby tripled! Dark Green Fritillary also had a good July with counts up a half and the spread through the county continues. Large Skipper also doubled but there are some loosers. Small Skipper is down to 75% of last year. The Large and Small White were halved continuing the trend of the bad start to the season but there is still some time in August for them to recover more. The big losers were our Nymphalids with Peacock counts only a tenth of last year, so far, and Comma and Red Admiral a half. In contrast Small Tortoiseshell has retained its massive increases of last year and is slightly up. Analysis table is presented below:
July 20th UPDATE 5 days of near 30'C and we are wilting but not the butterflies !! Few of us are venturing out to spot after our busiest day ever last Friday to near zero today. However transect counts continue at very high levels with many exceeding 200. Silver-washed Fritillary have seemingly exploded at its favourite site of Bishop Wood with more than double previous years counts. So, it is a great time to see mating pairs and lots of courtship dances. Female emergence has begun so male activity is feverish but in the hot weather they are stopping to take salts from the road frequently. The courtship dance is a most elaborate and unique and has never been filmed or photographed! Recent work by Ray Cannon from Scarborough has found that the insects actually touch during the loop the loop dance. The male passes under the female and then darts immediately upward so her antenna are drawn over the very evident sex brands of the male forewing. He then stalls so she overtakes and then he swoops back down underneath her and so the loop goes on lasting 1-2 seconds per loop. All this time she is going in a straight line down the ride. New season Peacock have now emerged and numbers are rising and also new season Brimstone and second generation Holly Blue. Ringlets and Meadow Brown remain at their peak but are joined in large numbers by Small Skippers and some fresh Essex . Large skippers are now declining quite fast as are Speckled Woods. A large peak in Large White and Green-vein white and good numbers of Hutchinsoni Comma . This summer form of the species will breed but not hibernate while the regular form will remain unmated till next spring and will go in and out of hibernation for the remainder of summer. Tortoiseshells numbers have dipped somewhat but Marbled White remain strong and Dark-green Fritillary are holding up but well past their peak now. We are also in the peak of the Purple and White-letters Hairstreaks. The Purple Emperor season started the middle of last week the latest season for many years by over three weeks but in Sherwood and North Notts numbers are strong and groups of us have been visiting to get familiar with this rapidly expanding species. Let me know if you want to see them and i can forward more details.
June Highlights: Why have there been so few butterflies?
Why have there been so few butterflies ? You might be forgiven to thinking this since the short burst of butterfly activity in the final days of May when the ghastly spring finally gave way to sunshine and warmth. This was promptly followed by the traditional June lull that has proven to be exceptionally deep and long because of the cold wet spring causing species to emerge two weeks late in many cases despite June being largely sunny , dry and warm . The disastrously low butterfly counts of May have continued till the third week of June when our summer species began to really take off, but, much slower to build than normal.
Picture of the Month by Chris Cox of Marbled White at Kiplingcotes Chalk Pit on the 26th June
Total counts were half those of 2020 over June from all our transects Apart from a short flush of Large White at the beginning of the month almost no whites have been seen flying throughout the month! Large Skipper were the first summer species to appear quite slowly then Meadow Browns and Dark Green Fritillary in the middle of the month with Ringlet a week later. Dark Green Fritillary continues to make progress with new colonies appearing northwards up the limestone ridge. Orange Tips, Green Hairstreak and Dingy Skipper continued flying to the middle of the month while they normally are all gone by the beginning of June. Marbled Whites also appeared in the third week of the month and as I write numbers are still going up, but, still no significant Small Skippers seen. Large Heath emerged on 9th , 2 weeks behind schedule, and have now peaked . The highlight of the month has to be the really good emergence of the first generation of Small Tortoiseshells with some recorders getting over 30 and a continuation of the good numbers carried over in hibernation from last year, in many cases they are the most common species seen this month. In addition reasonable numbers of migrant Painted Ladies appeared at the beginning of the month followed by Red Admiral later . The first White-letter Hairstreak on the 26th followed by Silver-washed Fritillary on the 29th, actually on time . Thank you for near 600 sightings this month despite the dearth and resultant waning enthusiasm.
Its is also possible that after 3 good summers for our butterflies that 2021 is an 'adjustment' in their trajectory which we should not be too surprised about.
May Highlights
Picture of the Month
Photo by Trevor Walton on May 12th at Hawnby
From Bad to much Worse! Is there Hope?
Could it get any worse than April? Well Yes! Nothing seen in the garden, transect walkers grounded or walks abandoned half way due to thunder, sleet or rain. Moth traps empty night after night. We are feeling the effects of 'La Nino' the cooling cycle linked to the 11 year cycle of sun spots. The result is a weak Jetstream which has sunk further south and west in an even more convoluted path than April, picking up low pressures and with cold arctic air still streaming into the north sea dumping their rain on the UK. It could prove to be the wettest May in 100 years and certainly in Yorkshire nearly 2-3 months rain has fallen. Average temperatures are down by over 2'C. Effectively we have had April in May. The grasses have flourished but flowering plants have been held back almost frozen in time at the beginning of May and are now at least two weeks behind. Peak daily temperatures have been 11-13'C and insufficient for flight and only Orange Tips seen in the brief sunny intervals. Transect walkers who managed to get out in marginal conditions saw very little with number less than half. Brimstone eggs laid on Buckthorn died in frosts or were predated by hungry birds . The weather finally broke on Friday 28th and a high pressure established over the UK and the long range forecast is for a good June. As I write Brimstones and even Small Tortoiseshell's, that had gone back into hibernation these last 7 weeks have reappeared. Yes , things can bounce back if the survivors get some flight time in the next 10 days. We have had more than 100 sightings come in in the last 3 days of May bringing the total for the month to near 400 although there has been many days of zero through this miserable month. We have had a run of nearly three good years for our butterflies and a disastrous spring is here to test that improvement's resilience. As always with butterflies, we should expect surprises!
This month best picture goes to Jessica Bone, taken in York on 25th April
April Highlights
Old Man Winter delivered icy kisses throughout the month which was dominated by northerly air streams and high pressure anchored over Greenland. Mereologically a weak polar vortex has lead to our jet stream being not only weak but undulating resulting in cold air being sucked out of the Arctic on all three northern hemisphere continents. Greece and Spain have suffered the largest snowfall for many years and the situation is mirrored in North America and Asia with crops ruined. Here our tender plants and blossom and even stinging nettles have been burnt. There was frost somewhere in the UK everyday of the month and Yorkshire had snow flurries for 10 days in a row over the Easter holiday. April was the driest, coldest, and sunniest almost ever recorded. Butterfly sighting however were good even with the cold and 300 sightings came into the website. Species continued to emerge illustrating its not just air temperature but the ground level microclimate warmed by the very sunny conditions led to Dingy Skipper being a day earlier than last year. Duke of Burgundy have appeared on time on the 26th. Orange Tip numbers have built up as have the Whites However the weather has seriously disrupted transect walking with some only achieving 1 walk so far this season. Thank you all those trying.
NB To have a chance of winning Picture of the month please do make entries in our sighting system of your latest pics.
March Highlights
Picture of the Month
This months best photo goes to Chris Cox taken on the Rail Trail at Keyingham VC61
The 2020 UKBMs results were published this month with Small Tortoiseshell being the stand out winner with some sites showing 300% increase in numbers. large and Small Whites, Brimstone, Holly Blue, Marbled White and Meadow Brown did well but even with this third good butterfly year in a row more species did badly than well. More on Yorkshire results HERE
It's been a long wait for the butterfly season to really start in Yorkshire taking till mid March for some sunny weather. This was followed by a 'Spanish plume' of warm air on 20-21st and then Saharan winds from North Africa on the 29th brought us our best spell with temperatures in the 20's and nearly 70 sighting records coming in during the last 3 days of the month. Its great to have 135 records in March into the new sightings system and over 200 so far this year from 33 recorders; see HERE. Thank you. The picture of the month goes to Chris Cox; see opposite. There have been very good numbers of our hibernators and some fantastic Brimstone counts from Bishop Wood and Brockadale plus a battered Painted Lady in Scarborough and a Hummingbird Hawk moth also seen. The first Holy Blue and Orange Tip have been seen and we can expect Speckled Woods, Wall, Small Heath and Green Hairstreaks any day. Nationally 2021 sees both the Large Tortoiseshell and the Clouded Yellow successfully overwinter on the Dorset coast, yet again indicating that they really want to become UK residents.
March saw the launch of our interactive Butterfly Atlas for Yorkshire which has won some international admiration as a first of its kind. Its a great tool to explore our countryside. It would be great if we can add our moth records as the next big challenge. Watch the demo video HERE and explore HERE
We also launched our online events and You tube channel to mark our progression to a new medium HERE. It has already allowed so much more interaction with our membership and brought people together throughout the county which was never practical before. We have used the opportunity to reinvigorate our formal recording which lags well behind our tremendous casual recording effort with training on UKBMS and species identification. There will be a number of transect restarting and some new ones this year including two of our best sites at Brockadale and Fordon Banks but we still need more interested volunteers with lots of spare time to repair the damage of the pandemic and staff losses from our charities.