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.