Saturday, 11 January 2020

The Butterflies of Northamptonshire in 2019

The fantastic butterfly season during 2018 was always going to be a difficult act to follow and although some species were down in 2019 the year still held some great success stories. Among 2019’s achievements was a very welcome spike in Peacock numbers, a Painted Lady invasion, the continued colonisation by Dark Green Fritillaries and the incredible news of the first Chequered Skippers to emerge in the wild in the county for nearly half a century. On a personal level highlights for me were being lucky enough to be monitoring on the day of the Chequered Skipper emergence (see post here) and also after the staggering 2018 Black Hairstreak season being able to find all the early stages of the species the following winter and spring (see post here). Weather wise 2019 was rather changeable to say the least. The year started mildly including a very unseasonably warm day in February where temperatures reached nearly 18c, but this was followed by a wet and windy spring where warm sunny days were few and far between. The summer didn’t fare much better and although July had some fine summer days August saw the return of high winds and rain and after a dry September rain reappeared at the end of the month leaving unsettled conditions to dominate for the rest of the year. Despite the often less than ideal butterfly recording conditions we once again saw a huge increase in records with a good coverage of the county. So far we have received 25,291 records detailing the locations of 103,558 individual butterflies so many thanks to everyone who sent in records. As the number of records have jumped so dramatically over the last few years I've compared the 2019 results in the below species accounts to three year averages, I have however also included ten year comparisons to some species that had an unusually good season in 2018 (such as the Blues and Hairstreaks). These records are made up from UKBMS transect data, the Wider Countryside Butterfly Survey, the Big Butterfly Count, casual recording and iRecord. The results of the Garden Butterfly survey and Migrant Watch will be added once the data is repatriated to county recorders early in 2020. We are lucky to have a dedicated gang of transect walkers in the county who do an amazing job recording along their routes every week and in 2020 two new transects will be monitored in Salcey Forest which is great news! There is also a great conservation volunteer effort in Northamptonshire and we have plenty of opportunities to help out at work parties during the winter months, regular events are put on by Woodland Wings, the Back from the Brink project and also the local Butterfly Conservation branch. If these are something you'd like to help with you can find work parties in your area on the Beds and Northants Butterfly Conservation website events page (click here), on social media and also in the fantastic branch newsletter.



Chequered Skipper
After the Back from the Brink project released 42 Belgian Chequered Skippers into Rockingham Forest in 2018 there was a lot of eager anticipation to see if their offspring had survived in the wild. In the Spring of 2019 Chequered Skippers emerged in Rockingham Forest for the first time in over 40 years! You can read more about it on the Roots of Rockingham section of the Back from the Brink Website (click here).

Chequered Skipper, Rockingham Forest, 2019
Small, Essex and Large Skipper
All three Skippers were up from the previous year with the Large Skipper especially having a good season. The Small Skipper was up 32% from the previous year and up 43% from the three year average, the Essex Skipper was up 33% from the previous year but down 39% from the three year average and the Large Skipper had a 75% increase from 2018 with is a 97% increase over the three average. The first Small Skippers were seen on the 6th of June at Ring Haw and Hollowell Pocket Park, the last Small Skipper was recorded on the 25th of August in Daventry garden. The first Essex Skipper was seen on the 23rd of June at Bradlaugh Fields and the last one on the 15th of August at Sulby Manor gardens. The first Large Skipper of the year was recorded on the 29th of May at Stanwick Lakes and the last were seen on the 20th of August at Hazelborough Forest and Fineshade Wood.


Essex Skipper





Dingy Skipper
The Dingy Skipper had a good year in the county with a 39% increase from 2018 which is 86% over the 3 year average. The first one was seen at Twywell Hills and Dales on the 17th of April and the last was recorded on the 30th of June at Fermyn Woods Country Park. The sites that held the biggest numbers were Twywell Hills and Dales, Great Morton Sale, Polebrook Airfield and Fermyn Country Park.

Dingy Skipper, Fermyn Country Park


Grizzled Skipper
Although the Grizzled Skippers were down 24% from 2018 they were still 25% above the three year average. Despite this decrease from the year before 2019 was notable for the species as three new locations were discovered with singles recorded at Bucknell Wood and Roade and 2 seen at the Nene Wetlands just by the Rushden Lakes shopping complex. The first Grizzled Skipper of the year was seen on the 17th of April at Twywell Hills and Dales and the last on the 4th of July at Polebrook Airfield. The best sites to see them was Twywell Hills and Dales, Barford Meadows, Fermyn Country Park, Great Morton Sale, Old Sulehay and Polebrook Airfield.


Grizzled Skipper




Wood White
The Wood White had an average year with a slight 10% increase over 2018. The first one was recorded on the 10th of May in Bucknell Wood and the last ones were seen on the 2nd of August in Hazelborough Forest and another (which may be a wanderer) on the 4th of August in Evenley Wood Garden. This species is known to occasionally wander quite far from it's known locations and can sometimes turn up in unexpected places. On the 1st of June one was seen at Summer Leys Nature Reserve and another was seen in Brampton Ash, of course these could also be indicators of nearby unknown colonies in private woodlands. The public sites that held the largest populations were Bucknell Wood, Salcey Forest and Hazelborough Forest. Unfortunately, with the exception of Wicken and Whistley Woods, all the other locations are in private woodlands but for now the species seems to be doing well in the county and will be helped by the excellent efforts put in by the Woodland Wings Project which encourages ride management to benefit the species.

Wood White, Salcey Forest



Clouded Yellow
The Clouded Yellow had a good year in Northamptonshire during 2018 so it was no surprise that 2019 would show a loss. They were down 79% from the previous year and down 43% from the three year average. Despite this we did have a handful of sightings with singles being recorded at Pitsford Nature Reserve, a Piddington garden, Titchmarsh Nature Reserve, Harrington Airfield, Woodford Halse and 2 were seen at the private Bozeat Quarry on the 29th of August. By far the best and most reliable site to see them was the National Trust's Lyveden New Bield with a peak count of 9 seen on the 21st of September. The first of the year was recorded on the 16th of July at Lyveden New Bield and the last was seen on the 22nd of October at Harrington Airfield.


Clouded Yellow, Lyveden New Bield

Brimstone
2019 turned out to be a good year for the Brimstone, they were up 73% over the previous year and up by 95% over the three year average. The first ones were seen on the 13th of February at Pitsford Reservoir and Salcey Forest and the last was recorded on the 22nd of November in Kettering. This is a species that can be encountered anywhere but the sites where the biggest counts came from were Wakerley Woods, Summer Leys Nature Reserve, Stanwick Lakes, Twywell Hills and Dales and the Nene Wetlands.

Brismstone, Salcey Forest




Large, Small and Green-veined White
The Large White had a good year and was 33% up from 2018 although Small and Green-veined Whites were both down with losses of 23% and 47% respectively. The analysis with the three year average shows the Large White up by 11%, the Small White up by 49% and the Green-veined White down by 18%. The first Large White of the year was seen on the 24th of March in Weldon and the last was seen on the 22nd of October at Ditchford Lakes. The first Small White was seen on the 25th of February in Kettering town centre which was followed by another early one on the 26th in Becketts Park in Northampton, the last Small Whites were recorded on the 22nd of October at Pitsford Nature Reserve and Woodford. The first Green-veined White was seen on the 29th of March near the Brampton Valley Way in the area near Merry Tom Lane in Brixworth and the last was seen on the 8th of October at Farthinghoe Nature Reserve.


Large White, Hazelborough Forest










Orange-tip
The Orange-tip did well in 2019 with a 47% increase over the previous year and a 105% increase over the three year average. The first were seen on the 24th of March at Clopton churchyard and at Duston Mill lake in Northampton, the last was seen on the 22nd of July in a Daventry garden. This species can be found pretty much anywhere where it's larval foodplant grows (Cuckoo Flower and Garlic Mustard) but the highest counts came from Stanwick Lakes, the Nene Wetlands, Summer Leys Nature Reserve, Old village, Hazelborough Forest and Merry Tom Lane near Brixworth.

Orange-tip

Green Hairstreak
The Green Hairstreak had an average year with a slight 2% increase from 2018 and a 7% increase over the three year average. The first one was seen on the 17th of April at Weekley Hall Wood quarry and the last was seen on the 15th of June at Twywell Hills and Dales. This is a very localised butterfly and the best sites to see them were Twywell Hills and Dales, Fermyn Country Park, Great Morton Sale, Weekley Hall Wood quarry and Ring Haw near Old Sulehay.


Green Hairstreak


Purple Hairstreak
The 2018 Purple Hairstreak season was extremely good so it's no surprise there was a big drop in numbers during 2019. They were 64% down from the previous year and 21% down from the three year average. The three year average figure is slightly misleading though due to the big numbers recorded during 2018 so looking at a longer term trend they were 88% above the ten year average therefore it can still be considered a good year for them. The first of the year was seen on the 28th of June in Salcey Forest and the last of the year was recorded on the 26th of August also in Salcey Forest. The best sites to see them were Glapthorn Cow Pastures, Whistley Wood, Hollowell Reservoir, Brampton Ash, Salcey Forest, Bucknell Wood and Fermyn Woods.

Purple Hairstreak, Bucknell Wood

Purple Hairstreak, Wakerley Wood.

White-letter Hairstreak
The White-letter Hairstreak had a slightly better than average year. Once again 2018 was an unusually good year for the species so 2019's 70% drop in numbers is to be expected although a 57% increase over the ten year trends does indicate a better than average year. The first one was seen on the 23rd of June at Glapthorn Cow Pastures and the last ones were recorded on the 3rd of August in Fineshade Wood and the Fox and Hounds pub garden in Harlestone.

White-letter Hairstreak, Bucknell Wood


Black Hairstreak
The Black Hairstreak was 60% down from the previous year but 4% up from the three year average. The superb 2018 season also meant the following winter and spring was the best opportunity to try and find the elusive early stages of the butterfly in the wild to understand more about this secretive insect. The first one was recorded on the 4th of June in Glapthorn Cow Pastures and the last was recorded on the 7th of July in Fermyn Woods. Without doubt the best site to see them remains Glapthorn Cow Pastures but they can also be seen in the Blackthorn thicket at the north end of Fermyn Country Park, Fermyn Woods and the rides south of the Horesbox car park in Salcey Forest.

Black Hairstreak Egg
Black Hairstreak Larva
Black Hairstreak Pupa
Black Hairstreak


Small Copper
The Small Copper had a higher than average year and despite being 43% down from the previous year they were still 22% above the three year average. The first ones were seen on the 18th of April at Ravensthorpe Reservoir and Thrapston Gravel Pits, the last one was recorded on the 19th of October near Wicksteeds Park. The species can be seen anywhere with suitable grassland and brownfield habitats but the highest counts came from Ravensthorpe Reservoir dam, Twywell Hills and Dales, Summer Leys Nature Reserve and Pitsford Reservoir.

Small Copper


Brown Argus
The Brown Argus did well in 2019 and although down by 33% from 2018 they were still 40% above their three year average. The first of the year was seen on the 23rd of April at Twywell Hills and Dales and the last was recorded on the 17th of September in Sudborough. The sites with the highest totals were Clifford Hill Gravel Pits (aka Nene Washlands), Harlestone Meadow, Polebrook Airfield, Summer Leys Nature Reserve, Ring Haw, Harrington Airfield and Twywell Hills and Dales.


Brown Argus

Common Blue
Like many of the other Blues and Hairstreaks the Common Blue had a superb season in 2018 so 2019 was always going to show a drop. They were down 70% from the previous year which equates to a 37% drop from the three year average. When looking at the ten year trend though the Common Blue shows a slight 7% increase. The first was seen on the 19th of April at the Nene Wetlands and the last of the year was seen on the 28th of September at Ring Haw. This is a fairly common grassland butterfly but the sites with the largest counts were Irchester Country Park, Polebrook Airfield, Bucknell Wood, Lyveden New Bield, Great Morton Sale, Nene Wetlands, Sywell Country Park, Ring Haw, Weekley Hall Wood quarry and around the Salcey Forest Solar Farm.


Common Blue

Common Blue


Holly Blue 
The Holly Blue saw a 10% decrease from 2018 but was still 53% above the three year average. The first of the year was seen on the 25th of March at Summer Leys Nature Reserve and the last of the year was seen on 18th of September on Brackmills Industrial Estate in Northampton. This is a species that can be seen in a variety of habitats but the best sites in 2019 were Abington Park, Brackley Cemetery, Wellingborough near Isebrook and London Road Cemetery in Kettering.


Holly Blue


White Admiral
The White Admiral shows a drop by 40% compared to 2018 but is only down by 4% from the three year average. The first one was seen on the 22nd of June in Glapthorn Cow Pastures and the last one of the year was seen on the 16th of August in Salcey Forest. The best sites to see them were Fermyn Woods, Salcey Forest, Bucknell Wood, Hazelborough Forest, Plumpton Wood and Harry's Park Wood.


White Admiral


Purple Emperor
Although slightly above the ten year average the Purple Emperor didn't have a particularly good year. The records show a 56% drop in numbers compared with 2018 and they were 25% down from the three year average. There was a degree of forestry in the Fermyn Wood complex the proceeding winter and although in the long run this should benefit many butterflies in the short term it may have effected Purple Emperor numbers at that site. They did seem to do well at other sites though and 16 were observed on the 9th of July in Salcey Forest. We also had some surprises in 2019 as singles appeared at Summer Leys Nature Reserve, along the footpath between Upper and Lower Harlestone, Wakerley Wood and a garden in Flore. The first of the year was seen on the 1st of July in Harry's Park Wood and the last ones of the year were recorded on the 4th of August in Fermyn Woods and the aforementioned Flore garden. Despite the forestry the best site in the county to see them still remains Fermyn Woods followed by Salcey Forest, Bucknell Wood and Hazelborough Forest. They have expanded their range a lot in recent years though and they can be encountered in most woods with a suitable mix of Oak and Sallow.


Purple Emperor, Salcey Forest

Purple Emperor, Salcey Forest

Purple Emperor, Horsebox Car Park, Salcey Forest.


Red Admiral
Like most of the butterflies that overwinter as an adult the Red Admiral had a good year in 2019. They were 309% up from 2018 and 73% above the three year average. The first one was seen on the 8th of January in Fineshade Wood and the last one was recorded on the 30th of December in Salcey Forest.

Red Admiral

Painted Lady
This migrant butterfly occasionally has invasion years and 2019 was certainly one of these. They were up from the previous year by 960% and up by the three year average by 910%. The last invasion year was exactly ten years prior to this back in 2009. They were seen all over the county in 2019 especially in peoples gardens and this spectacle no doubt encouraged a lot of the public to take part in the Big Butterfly Count.The first of the year was seen on the 23rd of February at Finedon Cally Banks and the last one was seen on the 22nd of October at Sywell Country Park.


Painted Lady, Salcey Forest

Small Tortoiseshell
The Small Tortoiseshell showed an 80% increase over the previous year and a 57% increase over the three year average. The first was seen on the 14th of February in a Finedon garden and the last Small Tortoiseshell seen on the wing was recorded on the 29th of October on the Westone Estate in Northampton.

Small Tortoiseshell

Peacock
The Peacock had a superb year in 2019 which was a bit of a surprise considering the lack of records during the summer the previous year. It has been theorised that they went into a period of aestivation (diapause caused by excessive heat) during the 2018 summer heatwave prior to overwintering. This seemed to be confirmed by the large amount of records for them in the Spring the following year. Peacock records show a 371% increase from the year before and a 318% increase over the three year average. The first of the year was seen on the 21st of February at Farthinghoe Nature Reserve and the last one was recorded on the 25th of November in Yelvertoft.

Peacock, Wakerley Wood

Comma
The Comma had a slightly better than average year with a 78% increase from the previous year and a 62% increase over the three year average. The first one was seen on the 11th of February in Hardingstone and the last one of the year was seen on the 29th of October at Lyveden New Bield.

Comma







Dark Green Fritillary
The Dark Green Fritillary has really gained a foothold in the county in recent years and the records recieved in 2019 certainly show a big increase in numbers. The species was 262% up from 2018 which is a 707% increase above the three year average. Although the populations are concentrated in the north of the county we did see some recorded at different sites with singles recorded at Croughton Quarry, Roade and Twywell Hills and Dales. The main sites for them though are Old Sulehay, Ring Haw, Fineshade Wood, Wakerley Wood and Great Morton Sale. The first of the year was seen on the 20th of June at Old Sulehey and the last of the year was seen on the 8th of August in Fineshade Wood.

Dark Green Fritillary

Silver-washed Fritillary
The Silver-washed Fritillary showed a slight 14% drop in numbers compared to 2018 but were still 35% above the three year average. They could be seen in most of our woodlands but the best sites in 2019 were Fermyn Woods, Bucknell Wood, Salcey Forest, Wakerley Wood, Fineshade Wood, Great Morton and Little Sale and Hazelborough Forest. The colour form valezina was also seen in most of the colonies but Bucknell Wood remains the best site in the county to see them.The first of the year was seen on the 18th of June in Salcey Forest and the last of the year was seen on the 26th of August in Bucknell Wood.

Silver-washed Fritillary


Speckled Wood
The Speckled Wood showed a slight decrease of 17% from the previous year but was 13% above the three year average. The first were seen on the 28th of March in Great Doddington, Barnes Meadow, Moulton and Piddington, the last of the year was recorded on the 16th of October in Yardley Chase.

Speckled Wood

Marbled White
The Marbled White is still increasing its range in the county and saw a slight increase of 9% over 2018 and a 49% increase over the three year average. This grassland species can be encountered on most suitable grassland sites but the best sites to see them are Twywell Hills and Dales, Bradlaugh Fields, Weekley Hall Wood quarry, Helmdon Old Station Yard, Polebrook Airfield, New Duston, Ring Haw and Old Sulehay and Barford Meadows. The first of the year was seen on the 15th of June at Twywell Hills and Dales and the last was seen on the 21st of August in Stefan Hill Pocket Park in Daventry.

Marbled White




Gatekeeper
The Gatekeeper had a great season in 2019 and were up by 102% from the previous year and up by 132% over the three year average. The first of the year was seen on the 24th of June in Great Oakley Hall Park and the last of the year was seen on the 5th of September in Kettering.

Gatekeeper



Meadow Brown
The Meadow Brown was up by 68% from the previous year and up by 120% over the three year average. The first of the year was seen on the 1st of June on the Nene Wetlands Nature Reserve and the last of the year was seen on the 28th of September at Ring Haw.


Meadow Brown

Ringlet
The Ringlet showed a 46% increase over 2018 and a 130% increase over the three year average. The first of the year was seen one the 1st of June on Moulton Park Industrial Estate and the last of the year was seen on the 22nd of August near Hellidon.

Ringlet



Small Heath 
The Small Heath saw a very small increase of 1% above 2018 but it was still 75% above the three year average. The best sites to see them in 2019 were Twywell Hills and Dales, Ring Haw, Croughton Quarry, Borough Hill near Daventry, Welford Quarry, Weekley Hall Wood quarry, Great Morton Sale and Barford Meadows. The first of the year was seen on the 19th of April at Ring Haw and the last of the year was recorded on the 28th of September also at Ring Haw.

Small Heath












5 comments:

  1. Excellent information, hopefully a good year to come,

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  2. Excellent information, hopefully a good year to come.

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  3. It's very pleasing to see the uptick in populations of most species. Sad that I missed the Wood White and Purple Emperor at Summer Leys as I was there so much last year. Here's to an even better 2020 and much more photography. Thanks David for your continued efforts.

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  4. Hi David I can't believe that I have just seen a Queen of Spain fritillary in my garden. It was definitely not a comma. Unfortunately by the time I got my phone camera it had flown. Is this species here this year? The weather conditions have been conducive for a channel crossing.
    Regards Kenneth

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  5. Today I saw a silver washed fritillary in Harlestone firs, this is the first fritillary I've ever seen. I was wondering if anyone else has seen them here?

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