Daytime Mothing in Bucks, 2017

As usual, I carried out a good deal of daytime moth-recording during 2017 and some of the highlights are presented here.  Most of the locations mentioned appear on the map below.

As happens in most years, activity started in early March with a search for Orange Underwing Archiearis parthenias and a single male was seen flying around the ancient birches by the car-park in Bernwood Forest on the 9th.  Several subsequent visits to Kingswood to look for the aspen-feeding Light Orange Underwing Archiearis notha didn't produce any sightings until the 27th when two were seen.  On 7th April my first captive Emperor Moth Saturnia pavonia emerged and (unusually) was a male, so he was released some distance away near Bicester in Oxfordshire.  The following day two females emerged so they allowed me to begin "assembling" once again, starting with the garden at Westcott where it took them nearly three hours to provoke any reaction from local males but then four turned up at once!  After a couple of unsuccessful trips out, on the 11th I finally had some luck with males called in at three locations in the Greatmoor area.  Over the next few days further success was had at Calvert Green, Dorton, Honeyburge & Oakley.  On 22nd April eggs laid following the garden pairing on 8th April began to hatch, thus starting the cycle over again.

Emperor Moth, Westcott 7th April 2017

On 2nd May I made my first visit of the year to the disused railway cutting west of Westcott where there are populations of Dingy and Grizzled Skipper and Green Hairstreak butterflies.  Amongst the moths seen there on that date were Adela reaumurella, Nematopogon swammerdamella, Incurvaria masculella, Glyphipterix fuscoviridella, Pammene rhediella, Grapholita jungiella and Pyrausta purpuralis.  On 5th May I called at Smalldean Lane Bank near Bradenham and amongst the micros active on this chalk grassland site was Falseuncaria ruficiliana.  I make regular visits to an old waste site at Woodham and on 9th May found several examples of Epiblema sticticana sitting around on colt's-foot, including a mated pair.  A search around scrubby wasteland near the Greatmoor incinerator on 18th May produced another interesting collection of micros, including Glyphipterix forsterella, Epinotia tetraquetrana, Dichrorampha aeratana & Dichrorampha plumbana as well as many Cydia ulicetana flying around gorse.  At Finemere Wood on 22nd May I found the smallest of the long-horn micros, Cauchas fibulella, active on germander speedwell.  My annual search for Forester Adscita statices commenced in earnest on 24th May when a single male was seen at Bernwood Meadows.  A visit to another Forester site at Doddershall the following day found no sign of the species but I did pot a Coleophorid disturbed from the meadow and after dissection it turned out to be the first proven record for Bucks of Coleophora frischiella.  On 30th May a drive out to inspect the verges of a road junction near Steeple Claydon produced eight examples of Chimney Sweeper Odezia atrata and a quick call at some rough ground near Calvert produced as expected the micro Pancalia leuwenhoekella, a dozen of them found resting on daisy flowers.  Further Chimney Sweepers were seen at Pilch Fields near Great Horwood in June, a BBOWT site which I visited monthly during the season.

Pammene rhediella, Westcott 2nd May 2017

Falseuncaria ruficiliana, Bradenham 5th May 2017

Epiblema sticticana pair, Woodham 9th May 2017

Dichrorampha aeratana, Greatmoor 18th May 2017

Cauchas fibulella, Finemere Wood 22nd May 2017

1st June was a red-letter day for daytime sightings.  Having done some research into sites in Bucks known to have wild liquorice Astragalus glycyphyllos, I went off in search of Grapholita pallifrontana which is a UK BAP priority micro-moth species that feeds on the plant.  The only record of the moth in Bucks comes from the Victoria County History so I wasn't holding out too much hope of finding it.  A check of a former food-plant site on the verge of the A509 near Sheringham proved negative (completely overgrown, no sign of liquorice) but another location near Weston Underwood came up with the goods and I found plenty of foodplant lining a farm track, complete with at least 18 of the moths spread along a stretch of a couple of hundred metres.  Result!  Another tortrix species was found resting on one of the wild liquorice plants and this proved to be Cochylis molliculana which seemed to turn up in lots of places in Bucks during 2017.  While in the area I decided to do some searching of hedgerows near Olney on the look-out for caterpillar nests of Small Eggar Eriogaster lanestris. The moth seems to be known in Bucks only from north of Milton Keynes and even then there have been exceedingly few records of it, probably because the adult flies so very early in the season (in February and March).  However, three males were light-trapped near Olney in 2017, one on 9th March and another two on 15th March at the same spot, so that seemed like a good area to look for larvae.  Even so, it still came as a great surprise when with little effort I discovered a nest of 200+ caterpillars on a south-facing hedge!

Grapholita pallifrontana, Weston Underwood 1st June 2017

Cochylis molliculana, Weston Underwood 1st June 2017

Small Eggar larval nest, Olney 1st June 2017

On 10th June I took the pheromone lure for Six-belted Clearwing Bembecia ichneumoniformis out to the disused railway west of Westcott where 11 of the moths appeared in no time at all.  I had further success at Calvert with the same lure in early July.  The MoD site at Arncott was visited for a butterfly survey on 24th June and Narrow-bordered Five-spot Burnet Zygaena lonicerae was recorded there, as was a day-flying Scarlet Tiger Callimorpha dominula (although the latter was actually just inside Oxfordshire).  On 4th July I took some experimental pheromone lures for the Burnet Moths out locally to give them a try.  They worked very well indeed at BBOWT's Calvert Jubilee and Leaches Farm Meadows reserves and at each site I managed to get Five-spot Burnet Zygaena trifolii in addition to Narrow-bordered Five-spot (and Six-spot Burnet Zygaena filipendulae).  Until 2007 it had been the accepted wisdom that only Narrow-bordered Five-spot was found in Bucks, but that year I discovered a small colony of Five-spot Burnets on the south side of the large land-fill at Calvert and this was written up in a note for the Entomologist's Gazette the following year.  It stood to reason that there would be further such colonies of the species in the local area and it was good to have this confirmed, especially as the original site was all but destroyed during the construction of the Greatmoor incinerator.  A clue that Five-spot Burnet might be present at a site is the prevalence of moths with confluent spots.

Five-spot Burnet, Calvert 4th July

Narrow-bordered Five-spot Burnet, Calvert 4th July

On 10th July I made a short visit to Chalfont Heights to see if Forester was still around and managed to find two active males (right at the end of their flight period).  This seemingly overlooked colony was only discovered in 2015 in what was thought to be a fairly well-recorded area for day-flying insects in South Bucks.  A look at two Chiltern chalk grassland sites on 25th July, one near Bradenham and the other near Cadsden, produced several sightings of the long-horn micro Nemophora metallica at both locations (sitting on scabious flowers) as well as Small Purple-barred Phytometra viridaria at the latter.

From late-July onwards my attention was mostly directed at leaf-mines.  On 29th July at Woodham I found mines of Phyllonorycter klemannella on alder (one was reared through back at home, the adult emerging on 11th August), while found at the same site on 31st July were active mines of Phyllonorycter comparella on grey poplar and on 21st September active mines of Stigmella assimilella on aspen.  A Bucks Invertebrate Group leaf-mine meeting was held at Black Park and the adjacent Rowley Wood on 14th October and it produced a good number of species, of which Stigmella nylandriella on rowan and Tischeria dodonaea on oak were new to me.

Moth Surveys in Bucks, 2017

For regular night-time moth surveys away from home, 2017 was one of those years where I started out with good intentions but things didn't quite go according to plan!  The weather played a part but from August onwards I had to spend a lot of time in Devon on family business so monthly surveys at some sites came to an abrupt end.  All the same, I managed to visit a reasonable number of sites spread across the county and obtained some useful records.

     Asham Meads (SP5914) owned by the Wildlife Trust
This was trapping for a Bucks Invertebrate Group field meeting held on 20th May.  The site is a collection of three large ridge-and-furrow wildflower meadows surrounding a copse mainly of oak, ash and blackthorn.  I ran two MV lights, one in the copse and the other in the eastern meadow.  Neither trap performed particularly well as the temperature dropped quite quickly.  Only 32 different species appeared and there was nothing unexpected, the meadow trap bringing in reasonable numbers of Anania fuscalis, Grass Rivulet and Small Square-spot (all to be expected in that habitat) while the most interesting things found in the copse were a larva of Merveille du Jour and a case of Luffia ferchaultella both on oak trunks.

Meadow trap at Asham Meads, 20th May 2017

     Ashridge Forest (SP9713) owned by the National Trust
The National Trust's annual public "Creatures of the Night" evening was held on 4th August and two MV lights were run for the event in the woodland area known as Pitstone Common, right on the border with Hertfordshire.  The traps performed slightly better than they have in previous years for the same event but even so only just over 40 species were recorded.  However, there was at least a bit of colour amongst those which did turn up and the 20 or more visiting members of the public went away happy. 

     Bernwood Forest (SP6110) owned by the Forestry Commission
Regular trapping in Bernwood, which is probably the largest expanse of (mainly) oak woodland in Bucks, continued throughout 2017 and I made 17 visits in all, spread between January and October.  One of those visits (on 8th July) was a joint Bucks Invertebrate Group and British Entomological & Natural History Society field meeting where 11 light traps were employed, spread over Oakley Wood, York's Wood and Hell Coppice, and it was particularly fruitful in that the Red Data Book species Triangle Heterogenea asella put in another appearance.  My own trapping visits during the year concentrated on Oakley Wood and York's Wood.  More than 400 different moth species were recorded and 18 of them were new to the list of moths recorded in the Forest since I began regular annual surveying there in 2009, taking the total to 809.  The new species were micros Antispila treitschkiella, Psyche casta, Crassa tinctella, Aproaerema anthyllidella, Eulamprotes unicolorella, Coleophora alcyonipennella, Elachista argentella, Ancylis obtusana, Gypsonoma minutana, Epiblema scutulana, Grapholita janthinana, Elegia similella, Cataclysta lemnata/Small China-mark, Nymphula nitidulata/Beautiful China-mark and macros Least Carpet Idaea rusticata, Mocha Cyclophora annularia, Narrow-winged Pug Eupithecia nanata, Small Rufous Coenobia rufa, while two further macro species (Purple Clay Diarsia brunnea and Suspected Parastichtis suspecta) hadn't been recorded since the 1960s.  There are historical records of a further 105 species from Bernwood so the site's all-time total is now well over 900.

Crassa tinctella, Oakley Wood 26th May 2017

Gypsonoma minutana, Oakley Wood 21st June 2017

Elegia similella, Oakley Wood 21st June 2017

Bernwood's nationally scarce specialities also put in their usual appearances, with Small Black Arches Meganola strigula (in June) and Common Fan-foot Pechipogo strigulata (in May and June) both being recorded, although it has to be said with fewer sightings than is normal.

Common Fan-foot, Oakley Wood 26th May 2017

     Burnham Beeches (SU9584) owned by the City of London Corporation
I joined Martin Albertini at Burnham Beeches on 5th August for another public "Creatures of the Night" event.  My two lights were run on remnant heathland and brought in only 20 species, almost exactly half the total achieved at the similar event the previous night at Ashridge!  However there were a few nice moths amongst them, including Dichomeris marginella and Pediasia contaminella which are not at all common in Bucks.

Dichomeris marginella, Burnham Beeches 5th August 2017

Pediasia contaminella, Burnham Beeches 5th August 2017

     Coombe Hill (SP8406) owned by the National Trust
This was one of the sites at which I'd hoped to trap monthly during the season but in the end things didn't work out and I managed only three visits, one each in April, May and July.  The best area of chalk grassland at Coombe Hill lies on the top, between the car-park and the monument, but I chose to survey much lower down the slope adjacent to Ellesborough golf course because that is where the Coombe Hill butterfly transect is walked.  The results weren't earth-shattering, with only just over 200 species recorded between the three visits.  Some nice micro-moths were seen, including Micropterix aruncella, Depressaria chaerophylli, Acompsia schmidtiellus, Thiotricha subocellea, Sophronia semicostella, Coleophora lixella, Mompha miscella & Delplanqueia inscriptella, most of which are typical finds on chalk grassland, but the macro-moths were almost without exception common and widespread species which could turn up anywhere in the county.  

Micropterix aruncella, Coombe Hill 23rd May 2017

Depressaria chaerophylli, Coombe Hill 9th April 2017

Sophronia semicostella, Coombe Hill 5th July 2017

One of the peculiarities of running traps at Coombe Hill (and at other sites in the immediate area, such as Grangelands) is the need to co-ordinate one's activities with the police at Chequers in order to avoid the possibility of a visit from an armed response unit!  

     Finemere Wood (SP7121) owned by the Wildlife Trust
A regular trapping haunt of mine since 2007 because it is so close to home, the species list at this woodland SSSI stood at 714 at the end of 2015, of which all but 46 species had been recorded by me over those nine years.  I gave the site a rest in 2016 but returned in 2017 and visited 22 times between February and December.  16 new species were added, comprising micros Stigmella aceris, Stigmella assimilella, Antispila treitschkiella, Adela croesella, Narycia duplicella, Luffia ferchaultella, Glyphipterix thrasonella, Glyphipterix fuscoviridella, Clepsis spectrana, Cnephasia incertana, Acleris logiana, Orthotaenia undulana, Epinotia abbreviana, Anania fuscalis along with macros Ghost Moth Hepialus humuli and Oak Nycteoline Nycteola revayana (the last one rather a surprising omission until now from this ancient oak woodland).

Acleris logiana, Finemere Wood 29th March 2017

The tortrix Acleris logiana is a species that is spreading quite rapidly through the county now, having first been found in 2009.  During 2017 I recorded it at Hog & Hollowhill Woods, on Rammamere Heath and in the garden at Westcott as well as at Finemere (examples were dissected from all four locations to prove their identity).

     Foxcote Reservoir (SP7136) managed by the Wildlife Trust
This under-recorded wetland site near Buckingham barely deserves a mention here.  A Bucks Invertebrate Group field meeting was held on 9th September, rather late in the season and during what turned out to be a month of relatively poor weather.  Only two of us attended, myself and the site's volunteer warden Bill Parker, on what was a very chilly evening and our two traps brought in a grand total of seven moth species before we gave up.  The site is still under-recorded!

     Hog & Hollowhill Woods (SU8185) managed by the Wildlife Trust
Following a daytime reconnaissance visit in February, three moth-trapping sessions were carried out here during the main part of the season, one each in May, June and July.  Owned by Bucks County Council, this is mixed deciduous woodland, mainly comprising beech and oak but there are also plenty of other tree varieties present so it is much more interesting than your typical Chiltern beech wood.  It was therefore all the more surprising that no moth recording had been carried out here previously.  300 different species were recorded during the three trapping visits and they included some really good finds.   One of the most significant discoveries was Triangle Heterogenea asella, with five individuals coming to light (two during the June visit and three in July).  Sir Eric Ansorge lists Bucks as one of the chief haunts of Triangle in the UK and according to Richard South it was "not uncommon in beech woods at Marlow", but until discovered in Bernwood Forest during 2010 the only fully documented records for the county came from the 1950s in High Heavens Wood (between Marlow and High Wycombe).  Little of that particular woodland still exists because much of it was felled on being turned over to landfill and even now the site is used for waste recycling.  Another good find was Olive Crescent Trisateles emortualis, of which a singleton appeared during the July visit.  Like Triangle, this is a Red Data Book species and there are previous records from this general area of Bucks up until the mid-1970s but none later than that.  However, the moth has known migratory tendencies and there were a handful of other records from adjacent counties at around the same time as this one, so that is perhaps a more likely explanation for the sighting.  Other good species seen included Mocha Cyclophora annularia, Royal Mantle Catarhoe cuculata, Beautiful Carpet Mesoleuca albicillata, Scallop Shell Rheumaptera undulata, Clouded Magpie Abraxas sylvata, Great Oak Beauty Hypomecis roboraria, Rosy Footman Miltochrista miniata and Red-necked Footman Atolmis rubricollis.  Interesting micros included Stenoptinea cyaneimarmorella (in Bucks otherwise known only from Burnham Beeches), Parornix fagivora, Ethmia dodecea, Monochroa cytisella, Recurvaria nanella and Ancylis upupana amongst many others.                    

Ancylis upupana, Hog & Hollowhill Woods 22nd May 2017

Triangle, Hog & Hollowhill Woods 26th June 2017

Beautiful Carpet, Hog & Hollowhill Woods 26th June 2017

Clouded Magpie, Hog & Hollowhill Woods 26th June 2017

Olive Crescent, Hog & Hollowhill Woods 17th July 2017

A return visit in November with Martin Albertini was to target Plumed Prominent Ptilophora plumigera and we were very pleased to find the moth in three of our four traps, adding another new site locally for this nationally scarce species.

     Holtspur Bottom (SU9190) managed by Butterfly Conservation
This was another Bucks Invertebrate Group field meeting, this time held on 24th June in good weather on this chalk grassland reversion site.  My two MV traps, plus a 15wt actinic run by one of the other participants, brought in around 160 species which was quite a good result.  Amongst the micro-moths, Pexicopia malvella and Eucosma parvulana (one of the three Eucosma species in the hohenwartiana group which need dissection to separate) were good catches, while the macro-moths included nice species such as Mocha Cyclophora annularia, Pretty Chalk Carpet Melanthia procellata and Kent Black Arches Meganola albula (of which nine were seen), although for the most part the list was just a good assemblage of common moths.  

     Ivinghoe Beacon (SP9516) and The Coombe (SP9615) both owned by the National Trust
On 30th March an early-season visit to The Coombe, an area of sloping meadow not far from the beacon car-park, resulted in the expected records for Northern Drab Orthosia opima but unfortunately not for Mottled Grey Colostygia multistrigaria which I last found in this area in 2012.  The impressive chalk grassland of Ivinghoe Beacon itself received just two visits using two MV lights each time, one on 24th May and the other on 19th June.  The May visit produced good numbers of Light Feathered Rustic Agrotis cinerea (13) and Broom Moth Melanchra pisi (15) while the June visit did likewise for Reddish Light Arches Apamea sublustris (24), all of which are regulars here.  Altogether 25 species were new to the Beacon but they were mostly common species, although it was nice to get another confirmed Bucks record for Eucosma fulvana (the third member of the hohenwartiana group, mentioned under Holtspur above).

Northern Drab, The Coombe 30th March

Light Feathered Rustic, Ivinghoe Beacon 24th May

   
     Rammamere Heath (SP9230) managed by the Greensand Trust
I prioritized Rammamere Heath in 2017 and here at least managed to complete the full survey as planned, making one daytime and six night-time visits between May and October.  Four MV lights were employed on each trapping visit, two on the younger heathland in SP9229 (where I had concentrated my efforts during previous surveys in 2011) and two more on the older heathland in SP9230.  All of the trap locations were within just a few metres of the Bedfordshire border.  A healthy 415 moth species were recorded during the 2017 survey, of which 147 were additional to those found in 2011.  Yarrow Pug Eupithecia millefoliata, Streak Chesias legatella and Bird's Wing Dipterygia scabriuscula were nice finds, being fairly uncommon in Bucks, but otherwise the additions were of fairly widespread species, few of which were habitat specialists of heathland.  Amongst the site's known rare species, White-line Dart Euxoa tritici and Archer's Dart Agrotis vestigialis both put in appearances (this being the only known location for either of them in Bucks), as did the nationally scarce Rosy Marbled Elaphria venustula, but otherwise the species list was just an excellent assemblage of relatively common moths.

Rosy Marbled, Rammamere Heath 14th June 2017

White-line Dart, Rammamere Heath 11th August 2017

Archer's Dart, Rammamere Heath 11th August 2017

     Stewkley (SP8325) privately owned
I was looking forward to trapping at this site because it lies within the least well recorded 10km square in Bucks.  This was a rare opportunity to obtain records from Blackland Covert which is just about the only sizeable piece of woodland in the 10km square, the remainder of it being almost entirely unproductive and sterile farmland.  At the invitation of the owner, a Bucks Invertebrate Group meeting was held at the site on 17th June and I joined the evening moth trapping session with two MV lights, running them on rides within the woodland which produced records for two adjacent tetrads.  The weather was kind and we did quite well, over 90 species being found in each of my traps for a combined total of 116.  When records from the four additional traps run by other participants are taken into account the final total will be closer to 150 species.  There was nothing particularly exciting at any of them, just a really good selection of common species.  Perhaps of most interest at my own lights was the sheer numbers of Double Dart Graphiphora augur, 27 being recorded which is the most I've ever had in one session anywhere.

Double Dart, Stewkley 17th June 2017

     Stoke Common (SU9885) owned by the City of London Corporation
Three trapping visits were made here during the year accompanied by Martin Albertini and Andy King, one in April, one in May and one in August.  We were again targeting Small Chocolate-tip but, once more, the species failed to show.  It hasn't been seen at this, its only known site in Bucks, since 2011 which is a bit worrying.  The moth's larvae feed on creeping willow Salix repens which is actually quite plentiful here amongst the heather.  The three visits produced 29 species which I haven't seen before at Stoke Common although I imagine that few of them will be completely new to this well-recorded site.  It was nice to see Cypress Pug Eupithecia phoeniceata and Larch Pug Eupithecia lariciata as well as species such as Neglected Rustic Xestia castanea, Dotted Clay Xestia baja and Heath Rustic Xestia agathina which are typical of that heathland habitat.  The biggest surprise, though, was on 26th August when Martin and I were sat minding our own business at one of my traps and a truly enormous beast appeared, circling round the trap before diving into nearby undergrowth.  It was immediately clear that this was Clifden Nonpareil Catocala fraxini and it was soon extracted from the vegetation into a large pot.  What a nice surprise!

Dotted Clay, Stoke Common 26th August 2017

Clifden Nonpareil, Stoke Common 26th August 2017

   
     Wooburn Moor (SU9190) privately owned
A small area of privately-owned chalk grassland close to the Holtspur Bottom reserve was visited by Neil Fletcher and I on 15th July.  There was space to run two traps (one each) and mine brought in an acceptable 92 species which included Parectopa ononidis, Coleophora lixella, Agonopterix ciliella (a rare moth in the county), Acompsia schmidtiellus, Pediasia contaminella, Cydalima perspectalis/Box Moth and Dark Spectacle Abrostola triplasia.  Two early instar caterpillars of Striped Lychnis Shargacucullia lychnitis were found feeding on one of 30+ dark mullein plants scattered across the site.

Agonopterix ciliella, Wooburn Moor 15th July 2017

Agonopterix ciliella, Wooburn Moor 15th July 2017

Dark Spectacle, Wooburn Moor 15th July 2017

Larvae of Striped Lychnis, Wooburn Moor 15th July 2017