2015 British Butterflies – 2: Duke of Burgundy at Noar Hill & Grizzled Skipper at Butser Hill, Hants – 20th Apr

Noar Hill is a Hampshire & Isle of White Wildlife Trust reserve where I previously observed Duke of Burgundy in  the 2011 and 2013 seasons, and so is a natural choice of site to include in this series. The hilltop (SU744319), just south of the village of Selborne, is characterised by former medieval chalk workings that created a patchwork of sheltered hollows and rich chalk scrub habitat (pictured below) ideal for chalk downland butterflies. This year the Dukes, one of Britain’s most vulnerable species, began flying on 15 April and should continue until late May.

DSC_0108 Arriving on site mid-morning I searched those areas with which I was familiar but could find no Dukes. Then I was fortunate to meet Butterfly Conservation’s Hants and IoW co-ordinator Ashley Whitlock who directed me to the new (for myself) location of his one sighting so far on this day. When I reached that spot Ashley and a companion arrived behind me and re-found the butterfly, a male (pictured below).

Duke of Burgundy (male)

Duke of Burgundy (male)

Duke of Burgundy are very territorial, so if an observer stays in the place where one is first seen that butterfly will keep coming back. Eventually a second male appeared, challenging the first one. It was now midday and warm sunshine prevailed. I moved on to a chalk pit where I had seen and photographed Dukes two years ago, finding two butterflies in exactly the same spot as then. I believe these were a male and female, the latter being the slightly larger and paler of the genders. Once again these insects kept returning to the same place.

In all I saw five Duke of Burgundy at this site and was told of one other. According to the British butterfly bible Thomas and Lewington this is a typical day’s haul for a downland colony, since adults emerge progressively from mid-April to late May and their average life span is five to seven days. I also observed my first few Holly Blue of the season here today, and Orange Tip were everywhere.

Female Duke (above) and on Cowslip food plant (below)

Female Duke of Burgundy (above) and on Cowslip food plant (below)

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In the afternoon I moved on another 14 miles or so to Butser Hill NNR (SU716203), the highest point on the chalk ridge of the South Downs. From the reserve car park I walked to the top end of Rake Bottom, a deep dry valley on the western flank of the hill that is a hotspot for Grizzled Skipper. I would guess this spectacular natural feature dwarves the fabled Devil’s Punchbowl on the Oxfordshire Downs by a third as much again in depth (pictured below).

Rake Bottom, Butser Hill NNR

Rake Bottom, Butser Hill NNR

I met a couple here who had walked up the valley from the lower end. They confirmed that the “Grizzles” were the most numerous species present and before long I began to see them as well. Being so tiny they are quite difficult to relocate after they jump out of the way in typical Skipper fashion. But I do not recall seeing so many of this butterfly in one location before. The afternoon was drawing on and I had bought just an hour’s parking time, so resolving to return to this site at some time in the future to see what else might be here, I left.

Grizzled Skipper

Grizzled Skipper

grizzled skepper.1502 rake bottom

And here are more “local” butterflies that I photographed along the Roman Road at Otmoor at the weekend. The Green-veined White is a first brood male, that can be almost pure white on the top side and much smaller than both their second brood counterparts and females.

In presenting my British butterfly year on this blog I will divide species into local and scarcer categories. Generally speaking “local” denotes anything that may commonly be seen in town gardens, while the “scarcer” ones are those that require particular sites or habitats to be visited. Each of the latter category will be reported under the same heading style as this post.

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Dinant Wallcreeper update

I have had an email from Robin Gailly, the Belgian birder who guided me to observing the long-staying Wallcreeper in Dinant on 22nd March. The bird last roosted in that town on 7th April and is now assumed to have departed. I am interested to learn that it was first found (on 30th December 2014) due to a group of local birders prospecting suitable sites for the species that they thought occurred more in south-east Belgium than was previously assumed. Robin tells me a second Wallcreeper wintered in a quarry near Liège.

I like this picture of the bird on the Palais de Justice wall just before disappearing into the dark cavity above it’s head for the night.

Wallcreeper (in failing light) (c) Robin Gailly

Wallcreeper (in failing light)
© Robin Gailly

2015 British Butterflies – 1: Green Hairstreak at Aston Rowant NNR, Oxon – 16th Apr

Yesterday I learned that in the last five days, while Oxonbirders have been beating our annual path to the Chiltern Escarpment to observe migrating Ring Ouzel, the little jewels that are Green Hairstreak have emerged nearby almost unnoticed. Mid-April represents a fairly early start to one of my favourite butterfly’s flight season. This is always a special moment in my wildlife calendar and with their appearance my heart is gladdened.

In presenting my British butterfly year on this blog I will divide species into local and scarcer categories. Generally speaking “local” denotes anything that may commonly be seen in town gardens, while the “scarcer” ones are those that require particular sites or habitats to be visited. Each of the latter category will be reported under the same heading style as this post.

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Green Hairstreak is usually the first scarcer species to appear, and a good place to see them at Aston Rowant NNR (SU730967) is along a brambly bottom edge of the chalk hillside just above the Sunken Way trail from the car park (see site plan above). A lot of this habitat had been newly cut but upon reaching an uncut portion lower down the slope I quickly saw a first butterfly. As I reached for my macro lens this individual flew back into cover and then there was a bit of a wait for another one to appear.

At this point sunlight was reduced by light cloud, but as soon as proper sunshine broke out the butterfly (below) emerged from cover to sit up and pose perfectly. What a delicate and understated little beauty, I just love ’em! I saw seven Green Hairstreak in all at this location, then walked around the reserve to prospect for more.

green hairstreak.1501 aston rowant

Green Hairstreak

If traffic noise is disregarded, from the M40 motorway that dissects the site, Aston Rowant NNR is a beautiful chalk hillside reserve. It is worth visiting just to experience the spectacular summer wildflowers that support an abundance of insect life including Dark Green Fritillary, Adonis Blue, Chalkhill Blue and Silver-spotted Skipper butterflies. I regard this place as my “home ground” and have spent many a contented hour here.

After the lower location I tried another spot just over the crown of Beacon Hill that had been described to me as supporting Green Hairstreak, but could not find any. Whilst taking a nature break there a bi-plane flew low and right over my head, proof not only that privacy can rarely be relied upon but that the tranquillity of no nature reserve (for those who seek it) is safe from the invasive species Plonkerus maximus.

Lastly I drove round to Linkey Down, just south of the M40 and the area where the Ring Ouzel are found. Seven were said to be present today but I saw just two of them in company with Wayne Bull. Other birders came and went but I was more concerned with butterflies today. The Green Hairstreak habitat here has been cut severely by English Nature in the last two years, and on encountering a working party recently I took the opportunity to enquire why. The explanation was that in managing a patchwork habitat EN must prioritise what should stay or go, and invasive Hawthorn had been removed here. No doubt there are sound habitat management reasons for this but I still regret the loss of what was a Green Hairstreak hotspot. I found none today though conditions became lightly overcast while I was there.

So what of “local” butterflies in the first half of April? Brimstone have been flying everywhere this sunny week, and Orange Tip are beginning to appear too. Of the hibernators, Peacock Butterfly and Small Tortoiseshell are plentiful and I recorded my first two Comma on a visit to the South Oxon Downs yesterday. In that location I also saw my year’s first Orange Tip and Small White, having seen a first Speckled Wood a week ago at Standlake Common.

Pulborough Brooks – 14th Apr

Yesterday I enjoyed a day out with Ewan Urquhart at the RSPB’s Pulborough Brooks reserve in Sussex. Since 1989 this site’s flood meadows (or “brooks”) of the Arun Valley have been managed both for grazing and wetland birds. There are also areas of grassland, woodland and heath here, with visitor trails to get the general public around and several hides.

River Arun flood meadows

River Arun flood meadows

One of the reserve’s summer bird specialities is breeding Nightingale and that was what we went to see. Ewan explained that this usually difficult to observe species is not only regular here but for some reason unusually showy. And I soon found out what he meant. The Nightingales favour an area at the foot of a path that descends from the visitor centre. There was other wildlife interest, notably Great Crested Newt and Adder, but we were here for Nightingale and fairly soon after our arrival one began to sing.

Last May when I was in southern Portugal there seemed to be one of these songsters in every other bush at some places, but they were rarely inclined to show themselves. In my early days in Oxfordshire in the late 1980s I recall them singing on parts of Otmoor but I didn’t ever set eyes on one. Last year I added the species to my Oxon list at another site but as in Cyprus, southern France and Portugal in recent years the local bird was seen just fleetingly, and that has always been my experience. At Pulborough Brooks … well these pictures tell the story. I will not be entering them into any competitions but I have previously been accustomed to much more foreground clutter obscuring my views.

Nightingale

Nightingale (above and below x 3)

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nightingale.1504 pulborough brooks

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and a Chiffchaff

… and a Chiffchaff

We saw probably just two birds but I received a text from Ewan today saying five more singing males had arrived. Some people yesterday were also hoping to see a Scarce or Yellow-legged Tortoiseshell butterfly that had been present in the same area of the reserve a week ago. There had been just one British record from1953 of this eastern European insect until the late summer of 2014 when there was an unusual migration to these shores. Like our British Small Tortoiseshell the visiting species hibernates, and a few individuals have re-emerged this spring in Norfolk, Cambridgeshire and here at Pulborough Brooks. After this first ever successful over wintering, butterfly enthusiasts are now hoping for breeding in Great Britain for the first time. See here for the full story.

Greater Yellowlegs at Titchfield Haven – 11th Apr

Today was the second time in 2015 that a particular north American wader passed through Hampshire County Council’s reserve at Titchfield Haven on The Solent. One Sunday back in January I had missed Greater Yellowlegs through not seeing the news in time to get down there. By the following day the bird, a lifer had gone. This time I picked up the news within an hour of it appearing on RBA and so got straight into my car and went.

My day had begun locally at Farmoor Reservoir where I met up with Tezzer and Mark. Some site passage specialities are passing through there at the moment but not while we were present. So we relocated to Linkey Down on the Chiltern escarpment where this spring’s first reported Ring Ouzel for that location had been seen earlier in the day. There we met several other Oxonbirders and thanks to the most sharp-eyed amongst the group I saw this species in our county for a fourth consecutive year *. I bowed out at that point, fortunately so given events a little further afield.

* I have since self-found  Ring Ouzel at another Oxfordshire location

* I have since self-found Ring Ouzel at another Oxfordshire location

When I arrived on site just before 4pm, the Greater Yellowlegs was sleeping to one side of Titchfield Haven’s Meon Shore Hide that was bulging with birders. Fairly soon the bird began to move around, being a lot smaller and greyer in appearance than the Black-tailed Godwits with which it was associating. The GY had a quick and delicate action and the diagnostic, slightly upturned bill was noticeable. But it was too distant to obtain clear pictures, this one (below) being as good as things got for me today.

Greater Yellowlegs

Greater Yellowlegs

Various other birds seemed to object to the visitor’s presence however, until the “Yank” fled exclaiming onto the River Meon nearer the coastal road. But it didn’t stay there for long before going inland again. When I got back to the Meon Shore Hide the Yellowlegs was not on view, though it had apparently dropped back in before flying off for good (see here).

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The scrapes at Titchfield Haven (pictured above) hold large numbers of breeding Black-headed and some Mediterranean Gull. This reserve was the first place, in March 2010 where I saw the latter species. Having picked out a nice group of them on the northern scrape, once the star visitor had been lost I walked round to the Pumfrett Hide to observe the gulls. These pictures (below) show how Med Gulls stand out amongst their Black-headed counterparts, with jet black masks, bright red beaks and legs, white wing tips and a different character. They are to my mind very striking and attractive birds.

Mediterranean (centre) and Black-headed Gulls

Mediterranean (centre) and Black-headed Gulls

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I looked in at the Meon Shore Hide again after 5:30pm but there had been no further sign of the Greater Yellowlegs and the crowd of visiting birders had largely dispersed. I was pleased to have had a second bite at this cherry and to gain another north American addition to my life list, and so headed home mindful of this day’s narrow window of opportunity.

Easter birds and insects around Oxford (review)

In my previous post I said local birding had become tedious. That was perhaps a little harsh as there have actually been some good birds in Oxfordshire recently. What had been most tedious was the overcast, soul-dampening weather that persisted through much of March. But all that changed over the Easter holiday weekend.

In recent days it has been possible to see three scarcer ducks locally  – Long-tailed, Ring-necked and Garganey – and then there is the Red-necked Grebe at Farmoor Reservoir. The last-named is currently gracing the site for it’s fourth consecutive passage season, and each time has drawn a lot of attention nationally. When this individual first appeared in the autumn of 2013 it was a county tick for more than a few seasoned Oxonbirders. Since then the Grebe has become a celebrity in our annual birding calendar, its presence always signalled by the attendant photographers. It is of course unusual to see this species in full breeding plumage in England, and the site is easily accessed from the A34 north-south trunk route.

Red-necked Grebe in pre-Easter murk

Red-necked Grebe in pre-Easter murk

Of the ducks, a female Long-tailed Duck has moved between various sites in Oxfordshire since last November (see here). Most recently this bird has taken up residence at Cassington gravel pits besides the A40 road west of Oxford, maintaining her preference for difficult to view sites with no public access. I couldn’t locate the bird here on two visits in the past six days, though others have been more fortunate.

On 1st April a drake Garganey arrived just north of Oxford on a lake at Stratfield Brake and has remained there each day since. This Woodlands Trust reserve is wedged in between the Oxford canal and a sports ground of the same name (SB). I first visited the following morning, accessing the site from a footbridge over the canal and meeting Oxon naturalist Wayne Bull. We could not locate the bird but I returned later in the morning and a visitor had been successful. I am more used to seeing this summer visitor in the middle distance, and at these closer quarters the subtle beauty of its breeding plumage stands out. The picture (below) is reasonable by my standards but still has a grey feel dictated by the weather conditions.

Drake Garganey

Drake Garganey

It subsequently transpired that this duck hugs the lake shore on the sports ground side and is often concealed in the marginal vegetation there. Many more pictures appeared on the Oxon Birding Blog (OBB) over the holiday period. Good Friday was a wet, dismal day but Saturday turned into something of a passage season classic.

En route a little later than intended to my weekly rendezvous with the Otmoor Massive, I met two cars heading the other way up Otmoor Lane belonging to Oxonbirders Tezzer and Mark. “Hello, something’s turned up,” I thought and indeed it had: four Ring-necked Duck at Standlake gravel pits to the south-west. Turning around, I called “The Wickster” (Tom Wickens) who leads a monthly first-Saturday walk at Farmoor Reservoir, and we arranged to meet there. In the event Tom had just one other walker besides myself on this day and we all agreed to go and see the RNDs. But before we left Farmoor an Osprey dropped in.

Tom is something of a grapevine maestro. Hence an observant birder tipped off patch worker Dai, who passed it on to Tom and I was in the right place at the right time for a chance encounter, my first local Osprey in three seasons. When this bird hit the water it seemed to stick there initially. Then the Osprey rose carrying an enormous Trout, one less for Farmoor’s fee paying anglers, to be mobbed immediately by gulls and crows. The visiting raptor circled ever higher until Tom guessed it was over Abingdon still clutching the fish and having evaded its pursuers. What a sighting! By now I was fully appreciative that none of this would have happened had I not been late heading to Otmoor in the first place. It was that sort of day!

Ring-necked Ducks (centre) (c) Adam Hartley

Drake Ring-necked (centre two) and Tufted Ducks
© Adam Hartley

Pit 60 at at Standlake gravel pits is managed as a nature reserve by the Lower Windrush Valley Project. When we arrived at the key holders’ hide on the north shore Tezzer and Mark had been joined by more of Oxon ‘s finest including Ewan and Gnome. The Ring-necked Ducks were in a  group away to the right and the three drakes were displaying amorous intent towards the lone female. Mating was filmed here a day later. The likelihood of four truly wild birds turning up in the same place in England had been greeted with scepticism initially. But through Saturday and Sunday this came to be accepted as a nationally significant sighting of the north American species, and was even a news item on Radio Oxford (see here).

From Pit 60 I followed Ewan and Mark back to Stratfield Brake for another look at the drake Garganey. Four more of these migrant wildfowl had meanwhile arrived at a site just outside of Thame, east of Oxford. I caught up with these (again three drakes and a female) later in the afternoon on a farm pond but they were too distant to photograph.

On Easter Sunday and Monday I made the effort to stay at home for part of the day and get on with some gardening. In the spring sunshine (at last!) hibernator butterflies, Small Tortoiseshell and Peacock Butterfly began flying at King’s Copse Park where I live. I also had my first garden Brimstone butterfly of the year and various bees and wasps were active. What a transformation the sunny conditions created, even tempting some fellow residents outside.

Large numbers of Scarlet Tiger moth larvae have survived the winter. These have munched their way through much of the invasive Green Alkanet in my wildlife garden and have also concentrated on the other original food plant Caucasian Comfrey. I am finding them on other plants too but the widespread devastation that I feared last autumn has not happened yet. In their hunger these larvae seem to turn to anything to eat, even Dandelions. When I find well grown ones on the walls of my park home again I assume they are crawling away to pupate. Adult moths are due in June.

Northern Wheatear

Northern Wheatear

Later in the afternoons of Sunday and Monday I paid my first visits of the year to the South Oxon Downs. The area above the villages of Blewbury and Aston Upthorpe is always an uplifting one to walk and contains SSSIs of butterfly importance that will be featured here later in the year. On Sunday I experienced a fairly large Corn Bunting and Yellowhammer roost above Woodway (SU532848) south of Blewbury. Then on Monday the highlight was the male Northern Wheatear (above) in Juniper Valley (SU545835), a reliable location for this species throughout the summer as well as in the passage season.

Drake Garganey again

Drake Garganey again

Today was sunny again after a cool, foggy start so I went out to photograph some of the birds in better light. First up was the Stratfield Brake Garganey that obliged as soon as I arrived on site. Then in the afternoon I enjoyed an extended session with the Red-necked Grebe, in company with visiting photographers as always. Some of the best pictures on OBB have made me wonder why I bother to attempt bird photography with my entry level SLR, but I am quite pleased with this shot.

Red-necked Grebe at Farmoor What a difference some sun makes!

Red-necked Grebe at Farmoor Reservoir
What a difference some sun makes!