2nd brood Adonis Blue at Chilterns sites + Otmoor Hawkers – 26-28th Aug & 7th Sep

In this greyest of English summers there are still some butterflies and dragonflies that have yet to be featured on this blog. The dismal end to August, as well as some good birds to go after, has ruled out including Lulworth Skipper in my British butterflies series. In the same way the wet end to July meant a long trip to north Lancs and Cumbria to record the “northern four” – High Brown Fritillary, Mountain Ringlet, Northern Brown Argus and Scotch Argus – will have to wait for another season at least.

Locally the only butterfly business still to do – other than photographing a Clouded Yellow – was checking out second brood Adonis Blue at my “home ground” Aston Rowant NNR (N), Oxon. I had resolved today to get on with some much needed gardening at home, but when yet more gloomy cloud settled upon Garsington in the early afternoon my noble intentions were defeated. It looked more cheerful over towards the Chilterns escarpment but the grey stuff seemed to follow me along the M40, to settle upon the reserve when I reached it.

On arrival I met fellow Oxon naturalist Chris Bottrell and a couple from Newark, Notts and they had not seen any Adonis. So a collective decision was taken to relocate to Yoesden Bank across the county boundary in Bucks. It still looked sunnier in that direction but guess what: the grey stuff followed us to that new location too. Chris decided to head home, leaving me to search this BBOWT reserve with Nick and Amy, the visitors. They had already seen their first Brown Hairstreak and Silver-spotted Skipper in God’s own county (Oxon) today and now hoped for the third lifer Adonis Blue, since none of these species occur in the East Midlands. Not only that but they had referred to this blog to help research their day out – nice people!

Adonis Blue (male)

So a chance encounter with other enthusiasts reminded me again how fortunate we are in Oxford to be within easy range of so many butterfly species. Yoesden Bank (SU789980), a steep sided stretch of flower rich chalk grassland to the east of a village Radnage, is England’s northernmost location for Adonis Blue and notable in also supporting Small and Chalkhill Blue in one place. The pursuing cloud decided to go no further east once we were on site here, but in a brief sunny interlude three male Adonis Blue (pictured above) showed themselves.

Nick and Amy from Notts

Nick and Amy from Notts

After leaving Yoesden Bank I returned to Aston Rowant hoping things might have brightened. In the event conditions were still overcast but it was too early to go home. So I followed the top footpath from the car park then trod directly down that part of the hillside above the M40 where I expect to find Adonis Blue. After disturbing two possible females I found a third perched on Marjoram, motionless in the cool early evening temperature. Then further down the hillside I came across two males, the first of which posed in a similar way to the female while the second buried itself deep in the sward. So maybe this cloudy afternoon had a silver lining, since I would not have captured these images (below) had it been sunny.

Adonis Blue (male)

Adonis Blue (male)

For a 2015 top wing picture of Adonis Blue at Aston Rowant NNR  see here.

Adonis Blue (female)

Adonis Blue (female)

During the previous two afternoons I visited the RSPB’s Otmoor reserve just north of Oxford to catch up with two hitherto late summer absentees from 2015’s Rn’S dragonfly records. Both Southern Hawker and Migrant Hawker were seen at this reliable location for each species, along with some ever unco-operative Brown Hawker and many Common and Ruddy Darter.

Migrant Hawker (male)

Migrant Hawker (male)

Addendum

7th Sep: After just over a week mostly of more oppressive murk the last two mornings have dawned cold and sunny. Cue “England set for Indian summer” headlines in the national press. Well, kids have just gone back to school. Following a report on RBA of a Red-backed Shrike on Otmoor I went out for a mooch around from 8am today, but no-one else was looking. But here was an opportunity finally to capture male Migrant Hawker for the autumn. This one (above) was warming up for the day along one of the Blackthorn hedges.

Red-footed Falcon at Willow Tree Fen, Lincs – 22nd Aug

This is another bird I have observed just once previously. I do recall the old Wiltshire sighting in the summer of 1989 and that it was fairly distant. Several of these attractive vagrant Falcons have been reported in England in 2015. I was first tempted by one at Wareham, Dorset back in the spring but didn’t bother to go for it in the end. Next I read of one near Stoke-on-Trent being enticed with food by batteries of 50 or more photographers, to hover above their heads while they competed for the perfect shot. To my mind, the unnaturalness of such a contrived situation meant that Falcon might as well have been in a zoo or brought out to perform for evening classes at a birds of prey centre somewhere.

Then a couple of weeks ago today’s little number turned up in the Lincolnshire fens. After going to north-Norfolk a week ago for an Icterine Warbler (see here) I realised that this latest Red-foot was well within my preferred range at a mere 110 miles. This was the one to go for and a very hot Saturday was an apt time to re-acquaint myself with the species.

Arriving on site just before 11am, I turned into a car park full of birders one of whom pointed out a hazy blob in his scope. By the time I set up my own scope the Red-footed Falcon had moved, so I followed the main track into Willow Tree Fen then turned left along the top of a dyke. Apparently, prior to my arrival the bird had posed for an hour on a fence post along this access track and hovered over people’s heads. When I caught up with the RFF it was hunting from a favoured tree, perched into the sun looking away from its audience most of the time.

Distant, hazy Red-footed Falcon

Distant, hazy Red-footed Falcon

Red-footed Falcon is similar in shape and flight to the more familiar Hobby, but hovers like a Kestrel though with deeper wing beats. A slate blue grey in tone with striking red undertail and legs in the adult male, they hawk mainly for insects from bushes, overhead wires or fence posts in a Shrike-like manner. I watched this one for some time in the heat haze before wandering off to explore some more of the reserve.

Willow Tree Fen (TF181213) was purchased by the Lincolnshire Wildlife Trust in 2009 since when the site has been restored from arable farmland back into the region’s largest area of natural fen habitat. The reserve comprises a mixture of reed beds, shallow meres, seasonally flooded pastures and hay meadows. This is part of an ongoing conservation programme to increase the county’s wild fenland by 200%.

Willow Tree Fen

Willow Tree Fen

After a lunch break I went back with my digiscoping collar to try to gain some at least half decent images. The Falcon had remained faithful to the same spot and the light was now better as cloud gathered ahead of a forecast showery breakdown. But as in the morning my efforts didn’t bear consideration. Then at some time after 3pm the bird began to move around the reserve more. Someone alerted me to a growing cluster of birders along the access track and I headed there. The situation had turned full circle from that time before my arrival, with the RFF hunting from fence posts to one side of the track.

Red-footed Falcon

Red-footed Falcon (1s male)

DSC_0109

Now I was rewarded for my uncharacteristic devotion of more than four hours to this bird. It’s admirers, most of whom had only just arrived, were being treated to displays of aerobatics, hovering and fairly close perching on fence posts. What a stunner! The expression “cracking bird” could have been coined just to describe it. With acceptable pictures taken and cumulo nimbus building up it was time to head home after a day well spent.

Spotted Sandpiper at Coate Water LNR, Wilts – 18th Aug

This was a nice and easy twitchette for a Nearctic wader that I had seen just once before. But I retain little recollection of that sighting somewhere in Cambridgeshire in 1993, and was abroad when much more recently a Spotted Sandpiper spent a few days at Oxford’s Farmoor Reservoir. Hence the appeal of a 30-mile drive today to the outskirts of swingingest Swindon.

Use of the bird hides at Coate Water requires a permit and key obtainable from the country park activity centre here. That meant a walk the longer way around the Y-shaped lake, but on reaching the LNR I was greeted by some birders one of whom said the visiting attraction was showing well. This Spotted Sandpiper was active in a muddy area to the right of a cramped and dingy hide that on my arrival held several other birders. But views of it were spoiled by an untidy protective fence (pictured below).

spotted sandpiper.1505 coate water

At a distance the adult individual at first looked like a Common Sandpiper but once I had it in my scope the dark breast spots, yellowish legs and bold supercilium all stood out. This was indeed a cracking bird. It now remained to wait for the Spot Sand to come closer to the hide and offer better photo opportunities. Eventually it did and these images (below) were the best I could obtain. The bird moved around the muddy area throughout my stay, feeding constantly as a steady trickle of people entered and left the hide to observe it.

spotted sandpiper.1501 coate water

Though a north American breeder, Spotted Sandpiper is a fairly regular vagrant to Great Britain with annual records mostly in late summer and autumn. The species is closely related to the slightly larger Common Sandpiper but distinctive by virtue of its breeding plumage and jerky flight style. I was pleased to get a fresh record of a vaguely remembered wader that had become just a name on my life list, and now hope it might hop across the county boundary into Oxfordshire. The May 2014 Farmoor bird was a county tick for quite a few high (ie 250+) listers but I was otherwise engaged in Portugal at that time.

Spot Sand watercolour

Spot Sand watercolour

Icterine Warbler at Burnham Overy Dunes, Norfolk + Wall Brown – 15th Aug

A fall of Eurasian drift migrants across eastern England on Friday prompted my first out-of-county birding twitch of the autumn passage. The outstanding candidates for me were two Icterine Warbler, a lifer on the north Norfolk coast. One of these birds was reported at Blakeney point, of 3-mile (each way) shingle spit walk fame. The second was about a mile from the nearest road at a spot just west of Holkham Pines, near the village of Burnham Overy Staithe. As usual I went for the easier option.

During the three hour outward drive Oxonbirders Tezzer and Andy kept me informed of relevant news on RBA, and when I got to my destination mid-morning plenty of cars were parked beside the A149 by a track out to Burnham Overy Dunes. That looked promising, then a man walking back told me the “Icky” was showing well and I picked out a cluster of birders some way off. The bird was pointed out as soon as I arrived on site and that was another of the more regular drift migrant warblers added to my British and life lists.

The

The “Icky” site from a distance

It being a first winter individual I expected a paler looking bird than I was actually observing. In the event the lemon yellow tone of this fairly large warbler was plain to see and the big orange bill also stood out. Other diagnostics are a pale wing panel, long primary projection and grey legs; but I expect lots of you know that because you’ve seen them before and I hadn’t until now! Today’s bird was quite showy to begin with, treating its audience to displays of feeding and preening at fairly close range. Then it relocated to the far side of the watching group and put on an even better performance.

icterine warbler.1501 holkham dunes

Large head, long wings, short tail

Like last winter, these images of a small passerine are as good as it’s likely to get with my equipment and show how the bird was seen. As the morning progressed and the number of birders grew the Icky became more skulking, offering less frequent views. So I checked with Norfolk people present whether there was anything else of note in the area, and on being told not began to meander my way homeward.

holkham dunes.1502 icky twitch

On the walk out and back to this site today I came across several Wall Brown, a butterfly that is more numerous in England around coasts during it’s larger August and September second brood. This species has the most intricate underwing pattern of all the British browns, as these pictures show. Grayling and Dark Green Fritillary were also active in the dunes and along the sea wall, adding a nice bonus to a successful twitch.

wall brown_01.1506 holkham dunes

Second brood Small Blue on the South Oxon Downs – 12th Aug

Yesterday afternoon I made the effort to visit a favourite Oxon site for one of my favourite butterflies. Small Blue, following their peak emergence in mid-May, produce a usually more limited second brood from late July through August. Pressure on the available sunny days in May (see here) meant I didn ‘t make it up to Lowbury Hill, the highest point on the downs above Blewbury. I last found Small Blue here in June 2012, so it was good to get sightings again upon fitting this little excursion into the Rn’S British butterfly summer.

Seeing them is usually weather dependent, and as the walk out and back from Westway above Blewbury is around five miles any attempt is best undertaken on a sunny day. But I always enjoy wandering on this part of the Downs whatever is or isn’t seen. Yesterday conditions improved through the afternoon, so by the time I arrived on site things were pretty much perfect for flying butterflies. I counted 8 – 9 Small Blue in all along a hedgerow just to the north of Lowbury Hill (SU540826) that is a hot spot. They are never easy to capture being so tiny but these pictures (below) compare with my best from previous years.

Small Blue

Small Blue

small blue_01.1505 lowbury hill

Amongst the other species flying here I was again struck by the size difference between individual female Common Blue and Brown Argus. Hence any potential Small Blue I picked out needed to be checked very carefully since some of those other butterflies were barely larger. To complicate things further the wingspan of Small Blue themselves can vary from 16 to 25mm. The food plants are Horseshoe and Kidney Vetch, and Common Bird’s-foot Trefoil. Typical colonies in isolated and sheltered locations number a few dozen adults though much larger concentrations do occur. And that’s the miniature jewels that are Britain’s smallest butterfly covered properly for the season.

New Forest Odonata – 3: Ashley Hole again – 8th Aug

A warm day being forecast I opted to pay a repeat visit to the heathland wilderness of Ashley Hole (SU228167) hoping for a better look at the Common Hawker dragonflies. Overnight murk was lifting on my arrival at Telegraph Hill and once I set out from there it was wall-to-wall sunshine for the rest of my stay. As I trod a familiar route to the boggy valley of the CH hotspot Grayling butterflies escaped my footfall, while Stonechat clicked and whistled amongst the heather and gorse. There is presently a family of these birds close to the parking area here and today the juveniles made a charming sight atop one bush.

Stonechat siblings

Stonechat siblings

View down the valley towards Ashley Bottom

View down the valley towards Ashley Bottom

I have to say that the fair weather conditions did not produce significantly greater numbers of flying odonata than a week ago (see here). But the Common Hawker were definitely more active with at least four males and two females seen. A year ago I spent about three hours watching two males patrol the same route around the bog in Ashley Bottom without settling. This time observing two more males hawking around the bomb craters for long periods was an interesting experience, but one of these perched for just a few seconds in which today’s only photo opportunity came and went. At the crater where I had disturbed a female last weekend, another or maybe the same one was egg laying in the pool-edge vegetation but she remained largely concealed whilst doing so.

Bog habitat in Ashley Bottom

Bog habitat in Ashley Bottom

Female Common Hawker laying eggs

Female Common Hawker laying eggs

As much as I like the wildness and beauty of this place there is a frustrating side to things here because Common Hawker are so difficult to photograph. It had taken four previous visits to gain a passable flight shot of a male, now would I ever capture a perched image of either gender? By early afternoon I decided to explore an area in the lowest part of the valley, then go on to Latchmore Brook to try to photograph Goldenrings. That relocation was rendered unnecessary because at least three male Golden-ringed Dragonfly were lazily patrolling the stream that flows though the valley floor, chasing each other away whenever their flight paths crossed. These perched frequently but didn’t like to do so against uncluttered backdrops.

Golden-ringed Dragonfly (male)

While I was prospecting for these pictures (above) another observer appeared, the first time that has happened in my five visits here, but when I eventually walked in his direction he hurried away. He had the air of an expert but I suppose I cannot pick and choose when I wish to be sociable. As on last weekend’s visit I didn’t find any Black Darter here which seemed strange. But at the first pool further up the valley as I walked away from Ashley Bottom I did come across just one of these bog specialists. The very acidic looking patches that they favour always make for interesting pictures and today was no exception.

black darter_01.1504 ashley hole

Upon leaving here I was suffering a little from wilderness fatigue and all too aware of the onset of another insect season’s end. Whether I will re-visit Ashley Hole in future years I cannot say, or perhaps it would be better to seek out Common Hawker in northern locations where they might be more plentiful. But whatever I decide this so evocative corner of the New Forest will always hold meaningful recollections.

ashley hole.1503 up valley

Goodbye to Ashley Hole for another season

Silver-spotted Skipper and more at NT Watlington Hill, Oxon – 7th Aug

On the southern flank of Watlington Hill on the Chilterns escarpment, a trail runs along a valley side where the great richness of the wild flora is matched when conditions are right by the insect life. The location (SU705934) is sheltered so in windy conditions butterflies funnel in here from the more exposed hilltop and western facing slopes of this National Trust site. And in a plentiful year such as 2015 for second brood chalkland butterflies this can be a place par excellence in which to observe them.

Site plan (click to enlarge)

Site plan (click to enlarge)

The trail begins from the NT car park at the top of the hill, emerging from woodland just before the steep open slope in the centre of the site plan (above). Around the base of that slope and in other more open areas good numbers of Silver-spotted Skipper and Chalkhill Blue were active. I recorded the first of those species for my British Butterflies series during the awful weather of late July. The battered and bedraggled individual that I posted pictures of on 28th (see here) conveyed the conditions in which it was found. That unfortunate butterfly emerged in a period of strong wind and torrential rain and possibly knew no different in its short life. But SSS are such photogenic little charmers when the sun is shining, and these pictures (below) taken today show how they should be experienced.

silver-spotted skipper_01.1502 watlington hill

I was struck today by the size variation in the hundreds of Common Blue present here. Collins Butterfly Guide says that in both sexes appreciable intra-seasonal differences occur and this demonstrates the ecological adaptability of the species. In the left-hand picture (below) the male Common Blue is smaller than the Brown Argus that has settled next to it. The right-hand specimen was so tiny that I wondered if I was seeing a first ever Small Blue at this site, until it revealed the underwing pattern of Common. The central picture shows a more usual size differential between male and female Common Blue.

And then there's the stunners that are Chalkhill Blue

Then there’s the stunners that are Chalkhill Blue

Lastly, here is a grasshopper du jour to add to my recent collection. I have now invested in a series of A5 laminated ID plates published by Peregrine Publications. These explain that grasshoppers cannot be identified reliably by colour since this varies tremendously between individuals of the same species. So there’s the explanation why I always have difficulty in matching my own photographs to field guides. I am pretty sure this one (below) is a Field Grasshopper that is widespread and common from July to October in dry short grassland.

Field Grasshopper

Field Grasshopper

I went out this afternoon thinking in terms of filling in time but was given a reminder that something more can always be squeezed out of any butterfly season. This was how things should be: a peaceful site, only manageable numbers of dog walkers and joggers, no traffic noise or light aircraft doing aerobatics overhead, no tourists or in-your-face paparazzi: just spectacular wild flowers supporting a wealth of fascinating wildlife to be enjoyed.