This is the only planned national butterfly item on my stripped-down 2022 wildlife agenda, affording as it does the opportunity to observe one of the remaining two British species I had yet to record, Mountain Ringlet and Chequered Skipper. The second butterfly was on my to do list in 2020, when flights from Luton to Inverness cost rather less than they do now.

Whilst experiencing truly-kosher CS in Scotland remains an ambition, I decided to tolerate the insurance measure of taking in the re-introduced colony near Corby, Northants. The hitherto closely guarded location was announced earlier this year, and guided walks commenced on 14th May, so today being a suitable weather window I went to take a look.

If I might sound less than enthused it is because I distrust re-introduction sites and dislike the social media-generated circuses they so often entail. But a regular wildlife colleague who is not bothered by such things had preceded me here last weekend and was not inconvenienced too much. They clearly went at the right time because today was quite hectic, exactly as I expected

I arrived on-site at the Forestry Commission Fineshade Wood complex (NN17 3BB – SP 981983 – see here) just before midday and after the guided walk had begun. Weather conditions were sunny but with a strong, cool breeze. Enquirers at the visitor centre were directed to a 5km running route (brown waymarks) that starts on the far side of the car park and leads into the prime CS area of Westhay Wood. After a while the shorter cut brambly habitat along this trail on either side began to assume a promisingly managed look. Then myself and two companions began to enquire of butterfly observers walking the other way.

All told of a hotspot further ahead where up to four Chequered Skipper were active. As we drew closer it became obvious where that location was and what ensued was no more nor less than I had anticipated. Around a dozen people, all with cameras were in place with lenses trained on a sheltered bank of brambles containing our collective quest. As each new person arrived they went straight in, which is only to be expected. There was no pushing and shoving but I myself am invariably far too polite on these more usually avoided occasions.

A couple of times I put myself forward and getting to the front gained the acceptable underwing studies of this post. The likelihood of a decent top-wing image in the prevailing ambience seemed slight. Enquiring of passing BC volunteer surveyors I learned this has been the prime CS hotspot of the season so far. One who had led the morning’s 30-strong guided walk said six individuals had been recorded during it, four of which were at this spot plus two singletons at some distance.

That to me sounded like small needles in very large haystacks if I elected to walk the entire 6km trail, and so I called things quits. BC and the Forestry Commission warn that only a small number of connects are likely at this early stage of their project. There is a huge amount of habitat here in which the expanding butterfly population could be concealed and visitors are under strict instruction not to walk away from hard paths.

Chequered Skipper had become extinct in England in 1976 and the Rockingham Forest complex of which Fineshade / Westhay Woods are part was a former stronghold. Following much work by Butterfly Conservation, Forestry England and other landowners to restore suitable habitat, re-introduction of stock collected from a thriving Belgian population began in 2018 (see here). Breeding success was confirmed in May the following year since when there have been further re-introductions to boost the evolving colony.

In England, the butterfly was historically found in a band of wet woodlands and associated limestone grassland from Oxfordshire to Cambridgeshire and into Lincolnshire. By the 1950s it had become restricted to Rockingham Forest and some sites in Lincolnshire. Then as with other habitat specialists the late 20th century decline in coppicing and management of open rides, in tandem with proliferation of conifer plantations led to the CS’s demise.

Chequered Skipper thrives in open, sunny areas within or on the edges of woodland. The “Back From the Brink” project here enabled parts of the former stronghold to be restored to ideal conditions over four years with an initial 7km of long, sunny rides created and 23ha of vegetation managed to deliver the required network of habitats. A planned second phase, running to March 2023 will extend habitat improvements into other areas of Rockingham Forest and establish further CS populations.

Adult CS are around 30mm in size with a fast erratic flight pattern. At today’s site eggs are laid on Wood Small-reed and False-brome, though a range of other grasses may be used as in continental Europe. Larvae emerge after around three weeks and like other Skippers at first thread the edges of grass blades around themselves to form a protective tube. After moving on to other plants to feed and grow they eventually hibernate through the winter to re-emerge in April.

Public interest in the project is expected to be great since over the previous 40 years it was necessary to travel to the Scottish Highlands to try to see this butterfly. Tales abound of people working the national list who made that effort for little or no reward. Having now converted this tiny, difficult species myself I wonder if going all that way specially would have been worth it after all. I would not say today was enjoyable but the bottom line is I have Chequered Skipper on my own British list, and there is only one more species, Mountain Ringlet to go.

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My route today enabled me to make my Wood White observations for this season in two places. On the way out I stopped for leg stretching exercise at my regular Bucknell Wood location (see here and here) near Silverstone, logging five individuals. Then on the return journey I made a personal first visit to Wicken Wood on the Bucks / Northants border. Since this butterfly died out in it’s last Oxon stronghold of Whitecross Green Wood in the early years of the last decade, records have issued almost annually from this other ancient woodland to the immediate west of Milton Keynes.

If successful today it would be my first ever BC UTB record of the species, which would be further welcome evolution after first ever Oxon Duke of Burgundy recently (see here). A large part of the Wicken / Leckhampstead Wood complex is also private but I presume the BC species champion and transect walkers have access to that key site. So I wanted to find out whether Wood White were observable along the publicly accessible trail that runs north to south through the woodland.

Parking in the late afternoon at SP730412, I rather pushed the now necessary leg stretching regime to the extreme by walking the entire length of the trail out then back. Within around 500 metres of the northern entrance gate I eventually came across two flying Wood White at around 5:30pm, but was unable to obtain pictures so those in this post come from Bucknell Wood. Not knowing exactly where the county border passes through the second woodland I cannot say on which side my sightings were, but I’m counting them as my first UTB records anyway.

My attention was caught earlier this week by a report of hundreds of Small Blue butterflies at a site on the South Oxon Downs. And what made that record all the more alluring was the mention of several Duke of Burgundy at the same place. I recalled being told several years ago of a Duke colony in the vicinity by a mysterious and enigmatic downs-man of local repute who is known by the epithet of “The Keeper”. But the location (as was his wont) had not been forthcoming. Now maybe word was out, at least for myself.

My local butterflying so far this season has been concentrated at Watlington Hill on the Chilterns escarpment, with spring specialities Green Hairstreak, Dingy and Grizzled Skipper, Brown Argus and Common Blue all recorded. But I’m not sure whether Small Blue occurs at that adopted patch, and Duke of Burgundy certainly doesn’t. The popular site of choice for the latter this season seems to have been Incombe Hole (see here) in north Bucks, which hence was bound to be a circus that my current petrol-saving mode gave a second reason to avoid. Now, today’s previously unvisited alternative offered an evolved experience, such as I seek for each of the title butterflies of this post.

So this morning I went to check things out. Parking at the roadside and walking along a right of way I quickly noticed large numbers of Small Blue in the trackside vegetation. Then, as soon as I found Cowslips I beheld a first Duke of Burgundy, though it was quite a worn specimen. Shortly afterwards the female in the picture (above) announced herself, and that was job done. This much sought species is reaching the end of its flight season now, but I had recorded it rather agreeably for another season.

I believe this is a remnant and fragile colony of Dukes and so will not publish the precise location herein. The BC Upper Thames Branch Atlas of Butterflies, published in 2016 cited just three remaining colonies on Lambourn Downs, of which one is private and specially managed for the species. Elsewhere in the survey region, DoB is restricted to a strong population at the Ivinghoe Beacon / Incombe Hole complex of north Bucks, and a smaller one at Bradenham in the same county. The only other recorded Oxon colony of living memory at Aston Upthorpe Downs near Cholsey and Blewbury has long been extinct.

All along the track a profusion of Small Blue (pictured above) continued, the most I have ever seen in one place. Brooks and Lewington describes such large occurrences of this most diminutive of British butterflies as few and far between, with the vast majority of colonies containing no more than 30 adults. These typically breed for many generations in very sheltered downland conditions where the soil is thin and unstable and the plant cover sparse and warm. Embankments, old quarries and dunes are all favoured habitats.

Emergence usually begins in mid-May with numbers peaking around three weeks later. A few may linger into July, almost overlapping with a small second brood. Adults are highly colonial, often being confined to no more than 200 sq m of land supporting perhaps two dozen Kidney Vetch food plants. As I saw today, males gather in sheltered, sunny hollows at the foot of slopes, perching for most of the day with wings half open 30 – 120cm above the ground and spaced 1 – 2 metres apart. Females visit these perching sites to be mated and thereafter avoid them.

Today’s experience afforded the opportunity to witness most of this behaviour, but not mating. In the past I have concentrated my Small Blue attentions in Oxfordshire mostly to the Ridgeway above the Devil’s Punchbowl near Wantage, Lowbury Hill above Aston Upthorpe that is now plagued by off-road motor cyclists, Lardon Chase above Streatley, and Hagbourne Railway Embankment. Today’s encounter with what is one of my favourite British butterflies was by far the most instructive and rewarding to date.

The Duke of Burgundy posts in this journal from different out of county sites have been well referred to over the last eight seasons, reflecting the enduring popularity of a much-sought item amongst British butterfly enthusiasts. For archive detail on the species see:

Duke of Burgundy at Incombe Hole, Bucks – 27 & 30th Apr 2021 – 178 views

Pearl-bordered Fritillary, DoB et al at West Wood Hants – 20th & 21st May 2019 – 356 views

Marsh Fritillary, DoB et al at Battlesbury Hill, Wilts – 19th May 2018 – 879 views

DoB @ Heyshott Down, Sussex and Noar Hill, Hants – 8 & 10th May 2018 – 110 views

Duke of Burgundy at Noar Hill, Hants and Butser Hill Sussex – 4 & 5th May 2018 – 192 views

Duke of Burgundy at Noar Hill, Hants – 20th April 2015 – 313 views

This all began back in the first lockdown of spring 2020. With local wildlife enthusiasts being limited to walking from home, an unprecedented number of Common Clubtail were recorded along the River Thames in Oxfordshire. These included at least eight sightings in Cholsey by a regular patch worker Alan Dawson. When Covid restrictions were lifted the emergence season for what is an iconic and especially sought dragonfly in Great Britain had passed. But my appetite had been whetted for an alternative Clubtail experience from the perennially frustrating classic sites of Goring and Pangbourne further downstream.

Cue more of the same. A year ago I visited BBOWT’s Cholsey Marsh reserve a number of times and guided by Alan learned where the hotspots were, but without success myself. After another patch regular alerted me twice to Clubtails he had found, then when I reached those spots they had flown I became disheartened and lost interest. This is a notoriously difficult dragonfly to connect with, since the opportunity usually occurs only in the brief “drying off” interval between their riverside emergence from the larval nympth and onward flight to the nearest suitable canopy. Once they are gone they are gone, as discount supermarkets like to say.

I had played out that patient but unrewarding scenario time and again at Goring and Pangbourne, and the negativity so induced was heightened by some of the emergences I witnessed being deformed or failed. Indeed I only ever recorded two healthy specimens, one in each location (see here and here). Now, going into 2022 with a much-reduced insect agenda, converting the Cholsey site for Clubtails has been an early goal.

My first visit this season was three days ago on 9th May. Despite mingling on site with patch royalty in the personae of Alan, Ian Lewington and Geoff Wyatt I was once more unsuccessful. Alan had seen one before I arrived and Geoff saw two after I left, but none of those Clubtails were perched. So the objective on my second visit today (12th) was to gain what would be only the third pictorial record for the site this season. The other two were by Alan (see here) and Lew (below) on 5th.

Cholsey Marsh is a scarce remaining example of the kind of riverside marsh that was once common prior to large-scale drainage of such habitat for agriculture. The wet reed and sedge beds here – punctuated with patches of grassland, willow scrub and ponds – are home to a rich spectrum of plants, invertebrates and birds amongst which the very localised Common Clubtail (Gomphus vulgatissimus) is a site speciality.

The larval stage of these insects is thought to last for between three to five years. The nympths require silt in which to burrow, and so the species is restricted to slow flowing or meandering river systems with sufficient deposits. Another requirement is bankside tree cover for adults, as at Cholsey Marsh, Goring and Pangbourne. Emergence on the Thames starts in early May, beginning around 8am to peak in the early afternoon, and most of the population hatches within a tightly synchronised period possibly as short as one week (per Brooks and R Lewington).

Emergence occurs close to the river banks on suitable support, and most healthy tenerals make their maiden flight after around two hours, typically onto higher vegetation at a short distance before dispersing into woodland up to 10km away. This species makes extensive use of the canopy. Because of this, the majority of records each season are of immature Clubtails in yellow and black colouring. Sightings of green-toned mature males are much less frequent, though I know a man who has done so (below).

Such mature males may return to the river from a week later, where they can be observed perching on exposed bankside vegetation, especially steep banks with good tree cover. They are territorial and disputes occur over the water where flying close to the surface they search for females that descend from the overhead treetops. Their flight season continues until the end of June.

Today (12th) I arrived on site at around 10am and walked the tow path downstream from the end of Ferry Lane (SU601854) to the “four arches” railway bridge. There are several dense stands of brambles, nettles and other vegetation along this route that provide suitable staging posts for newly emerged Clubtails. Those are the hotspots where most sightings occur and the closer they are to the river bank the better.

As three days earlier but this time alone I completed the outward leg then retraced my steps, and eventually there was what I sought: a very fresh, yellow and black Clubtail, perched at around head height. Facing away from the river (pictured above), this individual shows quite clearly how the species acquired its name – success at last! Cue celebratory exchanges of WhatsApps with my three earlier field colleagues, once the willing subject had flown off.

This item marks the first important conversion on my non-birding 2022 wildlife agenda. I made one further visit here before deciding that any chance of further success as the Clubtail flight season progresses was not worth the time that local patch workers can put in when they have other reasons for being there anyway. Trying to observe this dragonfly each spring remains a largely frustrating annual chore, but I have now cracked the enigma at Cholsey Marsh.