Thursday, 6 April 2017

Moth surveys in Bucks, 2016


2016 was the cut-off year for records in Butterfly Conservation's National Moth Recording Scheme database to be used in the forthcoming Atlas of Britain and Ireland's Larger Moths, due for publication in 2018.  As a result I had another busy year moth-trapping within Bucks and a total of 17 different sites were visited as shown on the map below. 


Needless to say, prior permission was obtained from the site owner in each case and ten of the locations received multiple trapping visits.  They are all dealt with below, for the most part in alphabetical order:


          Ashridge Forest (SP9713) owned by the National Trust

The single visit here was in support of another "Creatures of the Night" evening organised by the National Trust on 12th August.  Martin Albertini and I ran four traps in the woodland near the Ashridge Monument and, as often happens for this event, the catch wasn't all that good although this time it was slightly better than previous years.  My two MV lights brought in 58 species between them, of which there was nothing unexpected although Barred Hook-tip Watsonalla cultraria, Poplar Lutestring Tethea or, Haworth's Pug Eupithecia haworthiata and Antler Moth Cerapteryx graminis were nice to see, along with a good collection of Black Arches Lymantria monacha (19 altogether).


          Bernwood Forest (SP6210) owned by the Forestry Commission

15 trapping sessions were held in Bernwood Forest during 2016.  This was my eighth consecutive year of regular trapping here and even now the site's moth list continues to grow - the species total has reached 791 over those eight years.  There are historic records from Bernwood of another 107 species but a good many of those will no longer be current.  The best records from 2016 were obtained on 9th July when I was joined by Martin Albertini and Peter Hall, in excess of 170 species being recorded that night between our six traps.  A female Triangle Heterogenea asella appeared at one of Peter's traps in York's Wood quite early on in the evening, while a male was discovered under the sheet of one of my traps in Oakley Wood about three hours later as we packed up.  This diminutive Red Data Book species was found at Bernwood in 2010 after an absence from the county of more than 50 years, the lack of other sightings perhaps being explained by the fact that it is believed for the most part to be a canopy dweller and is rarely tempted down to ground level.

Triangle, Oakley Wood 9th July 2016

The Nationally Scarce species Small Black Arches Meganola strigula, Common Fan-foot Pechipogo strigulata and Dotted Fan-foot Macrochilo cribrumalis were also recorded that night, the first two being Bernwood specialities which are not known from any other sites in Bucks. 

Much of my trapping effort in 2016 took place in the M40 Compensation Area on the eastern edge of the forest and a good list of species was obtained there, including a female Fox Moth Macrothylacia rubi on 22nd May and Prochoreutis myllerana plus what must have been a wandering Fen Wainscot Arenostola phragnitidis both on 28th July.  All three are very uncommon species in the county.  For anyone who may be hoping to visit the Compensation Area from May 2017 onwards, be warned that the Highways Agency (who own the site) are about to renew the deer fence and when that work is complete the site will be padlocked and access will be by prior permission only.  

Fox Moth, M40 Compensation Area 28th July 2016

Prochoreutis myllerana, M40 Compensation Area
 28th July 2016

Fen Wainscot, M40 Compensation Area 28th July 2016

I joined a daytime leaf-mining visit by the Bucks Invertebrate Group on 15th October which added several new micro-moth species to the site list, but perhaps the best record that day was the discovery of an active case of Coleophora potentillae on the underside of a bramble leaf.  Another rare species in Bucks, this find can only have been a few hundred metres from where E.G.R.Waters had the only previous Bernwood record more than 50 years earlier.

Case of Coleophora potentillae on bramble,
 York's Wood 15th October 2016


          Brush Hill (SP8203) owned by the Chiltern Society

Brush Hill overlooking Princes Risborough, 23rd August 2016

This local nature reserve lies on the scarp slope of the Chilterns overlooking Princes Risborough.  It is mainly chalk grassland but with some interesting mixed woodland around the edge.  Visited with three MV traps once per month between April and September, the site produced a very acceptable list of 346 species from those six trapping sessions.  Typical species of the chalk such as Royal Mantle Catarhoe cuculata, Fern Horisme tersata, Pretty Chalk Carpet Melanthia procellata, Square-spotted Clay Xestia rhomboidea, Rosy Minor Mesoligia literosa and Small Purple-barred Phytometra viridaria all put in appearances.  It was also very nice to see Square Spot Paradarisa consonaria on 8th May (an uncommon species in Bucks these days) and a male Gypsy Moth Lymantria dispar on 23rd August.  The latter may have been a migrant but is more likely to have been dispersing from the colony which persists on the edge of Aylesbury.  Another surprise was the sheer numbers of Orange Sallow Xanthia citrago recorded in the traps on 18th September (38 of them!) but it transpires that part of the surrounding woodland contains a sizeable quantity of lime trees.  Although it is a reasonably common moth I've previously only ever recorded it in single figures on any one occasion.

Royal Mantle, Brush Hill 11th June 2016

Gypsy Moth, Brush Hill 23rd August 2016
 
Amongst the micro-moths recorded at Brush Hill were Micropterix tunbergella (it is always nice to see "Moth No.1" on the British list!), Depressaria pimpinellae & Depressaria douglasella (both Nationally Scarce) and the inevitable Delplanqueia inscriptella which was only recently confirmed as a British species having previously been confused with Pempeliella (now Delplanqueia) dilutella.  The moth is now quite widespread across the Chilterns on good chalk grassland sites like this and it seems that only inscriptella is found in our region, but the difficulty of telling them apart means that at least one example from each location needs to have its genitalia inspected.

Micropterix tunbergella, Brush Hill 8th May 2016

Depressaria pimpinellae, Brush Hill 28th May 2016


          College Lake (SP9314) managed by the Wildlife Trust
 
BBOWT's flagship reserve in Bucks was visited six times between April and September.  Four MV lights were employed on each visit, two of them on the best area of chalk grassland and the other two in the reed-beds, which meant that the two different habitat types on offer were given equal priority.  The species count from those six visits came to a magnificent 374, making it by far the most productive site trapped at during the year.

Amongst the many notable macro-moths on the chalk were Pimpinel Pug Eupithecia pimpinellata, Chimney Sweeper Odezia atrata, Annulet Charissa obscurata, Light Feathered Rustic Agrotis cinerea, Tawny Shears Hadena perplexa and Marbled Coronet Hadena confusa.  The reed-beds didn't disappoint either, with Southern Wainscot Mythimna straminea, Obscure Wainscot Mythimna obsoleta, Twin-spotted Wainscot Archanara geminipuncta, Brown-veined Wainscot Archanara dissoluta, Webb's Wainscot Archanara sparganii, Small Rufous Coenobia rufa and Silky Wainscot Chilodes maritimus all putting in appearances along with the more common wainscot species.

Chimney Sweeper, College Lake 22nd June 2016

Light Feathered Rustic, College Lake 30th May 2016
 
Tawny Shears, College Lake 22nd June 2016

Southern Wainscot, College Lake 23rd July 2016

Obscure Wainscot, College Lake 23rd July 2016

The micro-moths found at College Lake proved to be even more interesting with two species in particular, both of them Nationally Scarce, being excellent records for the county.  Cochylidia heydeniana was a first for Bucks while Gynnidomorpha luridana was only the second found in VC24.  Both were confirmed by dissection.

Cochylidia heydeniana, College Lake 22nd June 2016

Gynnidomorpha luridana, College Lake 23rd July 2016

In addition to the six trapping visits I also attended a National Moth Night event at College Lake on 11th June.  Traps had been run by several Bucks Invertebrate Group members and BBOWT staff the previous night and their contents were put on show to visitors in the morning, including a good selection of hawk moths.


          Dancersend (SP9008) managed by the Wildlife Trust

This was moth-trapping on 27th August at the end of a Bucks Invertebrate Group field meeting held at the southern (waterworks) end of BBOWT's Dancersend nature reserve.  My two MV lights were run on remnant chalk grassland and didn't produce much of particular interest although Stephensia brunnichella was a nice find and the appearance of Blastobasis adustella in large numbers (125 between the two lights) was certainly noteworthy. 


          Gussetts (SU7688), Hatchet (SU7889) & Homefield Woods (SU8186)

These three areas of mixed woodland in the Chilterns not far from Marlow, the first two privately-owned and the third owned by the Forestry Commission, were visited during November to search for the Nationally Scarce species Plumed Prominent Ptilophora armigera which flies at this unsociable time of year.  Bonfire Night is traditionally the time to start looking for this species but I delayed my first trip to Homefield Wood until 10th November.  This is normally the most reliable site in Bucks for the moth but on this occasion I drew a blank.  A return visit on 14th November was more successful with six males coming to light, five of them to an MV placed beneath the oldest field maple I could find.  The following night I visited Swain's Wood at Northend (see later) and got another two males, then on 23rd November I joined Martin Albertini at Hatchet Wood near Frieth where a single male Plumed Prominent was caught.  Gussetts Wood was visited on 24th November and, again, just a single male came to light. 

Plumed Prominent, Hatchet Wood 23rd November 2016

Plumed Prominent, Hatchet Wood 23rd November 2016

    
          Hughenden Valley Green Farm (SU8695) owned by the National Trust

Green Farm overlooking High Wycombe, 2nd August 2016

Green Farm is a large chalk grassland site immediately to the north-west of High Wycombe and overlooks the town.  Traps were run there four times between April and September (rather fewer occasions than had originally been planned) but a reasonable species count of 200 moths was still achieved.  The majority of the records were of common and widespread species but the pick of the bunch has to be a Netted Pug Eupithecia venosata which came to light on 26th May.

Netted Pug, Green Farm 26th May 2016


          Milton Keynes Lodge Lake (SP8338) & Walton Lake (SP8837)

Lodge Lake, Milton Keynes, February 2016

Walton Lake, Milton Keynes, February 2016

These two sites are managed by the Milton Keynes Parks Trust.  Lodge Lake at Loughton is adjacent to the West Coast Main Line in Central Milton Keynes while Walton Lake at Woughton Park is in a slightly more rural setting adjacent to the Open University campus.  Both have reed-beds but those at Walton Lake are substantial and are probably the oldest in the area.  Lodge Lake was only visited twice during the season and suffers a great deal from light pollution.  Reed-feeding species recorded there included Chilo phragmitella, Schoenobius gigantella, Southern Wainscot Mythimna straminea and Silky Wainscot Chilodes maritimus but otherwise the site produced little of particular interest.  Affected rather less by light pollution, Walton Lake was visited five times between April and September and proved to have a good assemblage of common species as well as more of the expected habitat specialists.  In addition to those seen at Lodge Lake, Walton Lake also produced Orthotelia sparganella, Calamotropha paludella, Donacaula forficella, Obscure Wainscot Mythimna obsoleta, Crescent Celaena leucostigma, Twin-spotted Wainscot Archanara geminipuncta, Brown-veined Wainscot Archanara dissoluta and Webb's Wainscot Archanara sparganii.

Orthotaelia sparganella, Walton Lake 18th August 2016

Crescent, Walton Lake 18th August 2016


          Rammamere Heath (SP9229) managed by the Greensand Trust

This was another single moth-trapping visit at the end of a joint Bucks and Beds Invertebrate Group event held on 28th May.  My three traps produced a grand total of 45 species on what was a rather chilly night and there was little of significance apart from single examples of Larch Pug Eupithecia lariciata and Broom Moth Melanchra pisi.  The most abundant moth of the evening was Light Brocade Lacanobia w-latinum (26 caught).

 
Broom Moth, Rammamere Heath 28th May


          Rushbeds Wood (SP6615) owned by the Wildlife Trust

Quite close to home and unusual in that it wasn't "coniferised" by the Forestry Commission during the 1950s and 1960s, I had trapped regularly at this damp deciduous woodland site between 2007 and 2009 and thought it was about time for some further surveying.  In 2016 I ran traps there on 16 occasions between January and December.  The resulting list of 265 moth species didn't break any records and there was nothing particularly noteworthy amongst them apart from Lobesia reliquana and Triple-spotted Pug Eupithecia trisignaria, both of which were first records for the site.  The wood has always been good for Poplar Lutestring Tethea or and White-marked Cerastis leucographa, both of which turned up in good numbers, and it was also nice to see Scallop Shell Rheumaptera undulata and Red-necked Footman Atolmis rubricollis.  After a wave of sightings at various locations in the county between 2013 and 2015, this would be the only Red-necked Footman I recorded anywhere in Bucks during 2016.

Lobesia reliquana, Rushbeds Wood 4th June 2016

Poplar Lutestring, Rushbeds Wood 17th May 2016

White-marked, Rushbeds Wood 1st April 2016


          Stoke Common (SU9885) owned by the City of London Corporation

I accompanied Martin Albertini to this excellent heathland site on three occasions during 2016.  An early season visit on 12th May had as its main target Small Chocolate-tip Clostera pigra but unfortunately the species failed to appear.  The moth has not been recorded here, its only known site in Bucks, since 2011.  Highlights from this and the other two visits, one in June and one in September, included Fox Moth Macrothylacia rubi (two females to the same trap), Emperor Moth Saturnia pavonia (one female to light, the site's first post-millennium record of this species which is most odd considering how extensive the heather is here), Grass Wave Perconia strigillaria, Beautiful Yellow Underwing Anarta myrtilli, True Lover's Knot Lycophotia porphyrea, Neglected Rustic Xestia castanea and Heath Rustic Xestia agathina.   

Fox Moths, Stoke Common 6th June 2016

Neglected Rustic, Stoke Common 6th September 2016


          Swain's Wood (SU7392) managed by the Wildlife Trust

Swain's Wood, February 2016

This permit-only nature reserve is a very steep-sloping chalk grassland bank surrounded by typical Chilterns beech woodland. Simply getting the equipment onto the grassland involved skills in mountaineering but it was worth the effort!  Three day-time and seven night-time visits were made between April and November and they resulted in 342 species being recorded, a very respectable total.  Nationally Scarce micro species comprised Nemophora metallica, Stephensia brunnichella, Elachista biatomella, Elachista subocellea, Agonopterix nanatella, Eulamprotes unicolorella, Acompsia schmidtiellus, Rhopobota stagnana, Hypochalcia ahenella & Merrifieldia baliodactylus.  Of these, Agonopterix nanatella was the first ever adult sighting of this species for VC24, the previous two records both being of larvae.  Another noteworthy micro was Delplanqueia inscriptella which was confirmed by dissection (see earlier under Brush Hill).

Nemophora metallica, Swain's Wood 26th July 2016 

Elachista subocellea, Swain's Wood 9th June 2016

Agonopterix nanatella, Swain's Wood 7th July 2016

Delplanqueia inscriptella, Swain's Wood 9th June 2016

Macro-moths sightings included Mocha Cyclophora annularia, Royal Mantle Catarhoe cuculata, Plumed Prominent Ptilophora plumigera, Kent Black Arches Meganola albula (present on site in some numbers, 21 being noted on 7th July) and several larvae of Striped Lychnis Shargacucullia lychnitis

Kent Black Arches, Swain's Wood 7th July 2016

Early instar larva of Striped Lychnis, Swain's Wood 26th July


          Turville Heath (SU7491) common land

This was a single night's moth-trapping on 2nd July in support of a Bucks Invertebrate Group field meeting held in memory of long-time moth enthusiast Tony Harman who lived in the village and had sadly passed away in September 2015.  After dark the temperature dropped very quickly and there were few moths around, my traps bringing in only 44 species.  Nearly all were common and widespread species and the only one of passing interest was a Gold Swift Phymatopus hecta


          Wotton Lakes (SP6817) privately owned

The Warrells at Wotton Underwood, February 2016 

Being less than three kilometres from home, I'd often thought that the lakes on the 200-acre private estate of the manor house in Wotton Underwood might be the source of some of the wetland moth species which I occasionally get in my garden at Westcott.  The lakes there were laid out in the mid-1700s by Capability Brown who was previously the head gardener at Stowe in the north of the county.  For 2016 I sought and obtained permission to trap regularly around The Warrells, the lake closest to the manor house which currently has the most extensive reed-beds.  Six visits at roughly one month intervals were made between April and September and produced a final list of 215 mostly common and widespread species, but they did include wetland specialists such as Calamotropha paludella, Schoenobius gigantella, Southern Wainscot Mythimna straminea, Obscure Wainscot Mythimna obsoleta, Bulrush Wainscot Nonagria typhae, Twin-spotted Wainscot Archanara geminipuncta, Brown-veined Wainscot Archanara dissoluta, Webb's Wainscot Archanara sparganii and Silky Wainscot Chilodes maritimus.   

Twin-spotted Wainscot, Wotton Lakes 15th August 2016

Brown-veined Wainscot, Wotton Lakes 15th August 2016

Webb's Wainscot, Wotton Lakes 15th August 2016



Sunday, 8 January 2017

Species counts per 10km square

Slightly more than 1,600 moth species had been recorded in Bucks by the beginning of 2016.  They comprise just over 620 macro-moths, a figure thought to be a fair reflection of current and former residents of the county.  The balance of some 980 micro-moths might seem to be a respectable total but that figure is by no means complete as a browse through John Langmaid's species maps on the Moths Count website will reveal.  Hard work, particularly over the past decade, has improved the situation considerably but new micros continue to be added to the county list on a regular basis and there is still plenty of scope for many more to be found.  The map below gives species counts per 10km square for VC24, correct to the beginning of 2016. 


Further recording effort during the course of 2016 will have ensured that Bucks now has at least three 10km squares with 1,000+ moth species, with others getting very close to that milestone.  The two shown above include Bernwood Forest (SP61) and Burnham Beeches (SU98).


Monday, 19 December 2016

Westcott, Bucks - the year 2016 in review



Butterflies

It was another poor year for butterflies in the garden at Westcott.  Only 19 species were recorded from the all-time list of 30 and one particularly surprising absentee was Ringlet Aphantopus hyperantus even though it seemed to do quite well in the local area.  Perhaps it did appear but when my back was turned.  ‘Empty buddleias’ sums up much of the summer and it wasn’t until the second half of August that any of the vanessids started to appear in numbers.  Peacock Aglais io never really got going at all before heading off into hibernation and the maximum seen at any one time was six, whereas counts of 40 or 50 are not uncommon here in a normal year.  Small Tortoiseshell Aglais urticae did moderately well, building to a maximum of 33 on 30th August, but it was left to Red Admiral Vanessa atalanta to hold the fort later in the season once the ivy had come into bloom, that species achieving a maximum of 21 on 24th September.  Comma Polygonia c-album was active from mid-July until mid-October but only ever appears here in ones and twos and it was no different this year.  The migrant Painted Lady Vanessa cardui was reasonably regular from the beginning of August (three were seen together on buddleia on the 3rd) and was noted on-and-off until the final sighting on ivy on 2nd October.

Another absentee in 2016 was Small Skipper Thymelicus sylvestris, although both Essex Skipper Thymelicus lineola and Large Skipper Ochlodes sylvanus did put in their usual handful of appearances during July.
 
Essex Skipper, Westcott 23rd July
 
Once again the elms at the bottom of our garden produced half a dozen of sightings of White-letter Hairstreak Satyrium w-album during the second half of July.  However, another of the trees succumbed to Dutch Elm Disease in 2016 and we are now left with only two on which the butterfly might still breed although regrowth from earlier losses is coming along nicely.  Unusually, on 23rd July I managed to get a half-decent photograph of one slightly battered individual which left the tree-tops to visit some bramble blossom.
 
White-letter Hairstreak, Westcott 23rd July
 
The only noticeable butterfly success story in 2016 was that of Holly Blue Celastrina argiolus, with activity from up to four individuals at a time noted on 51 days between 3rd May and 4th September.  In past years I’ve seen females egg-laying on our large Cherry Laurel and that is certainly the most favoured plant here on which to see basking adults, but we do also have plenty of its regular food-plants in the garden too (holly and ivy).

Holly Blue, Westcott 14th May


Moths

Trapping effort in the garden was almost identical to that of 2015 with the twin-30wt actinic light being run on every suitable night throughout the year, supplemented and/or replaced by the 125wt Mercury Vapour during the main part of the season.  The final species count was 629 (313 micro-moths, 316 macro-moths) which is actually just four short of the previous year’s record tally even though activity during the first half of 2016 seemed to be very slow indeed, far worse than in 2015, and suggested it would not be a vintage year.  The 30 micro and three macro species listed below proved to be new for the site list and they take the overall garden moth total to 906: 
 

4.002
Stigmella lapponica (mine on Birch)
25th June
4.007
Stigmella luteella (mine on Birch)
14th Oct
4.012
Stigmella aceris (mine on Norway Maple)
1st Nov
12.044
Haplotinea insectella *
17th July
15.056
Phyllonorycter salicicolella *
21st July
15.064
Phyllonorycter coryli (mine on Hazel)
9th Sept
15.076
Phyllonorycter emberizaepennella (mine on Snowberry)
10th Oct
15.081
Phyllonorycter nicellii (mine on Hazel)
5th Oct
20.007
Argyresthia cupressella *
20th June
20.015
Argyresthia curvella
20th June
28.024
Tachystola acroxantha *
16th July
30.001
Agnoea (Pseudatemelia) flavifrontella *
3rd June
34.012
Sorhagenia rhamniella *
20th July
35.143
Teleiodes luculella
10th June
37.011
Coleophora badiipennella *
21st July
38.046
Elachista albidella *
29th July
45.012
Stenoptilia pterodactyla *
27th July
48.002
Prochoreutis myllerana *
27th July
49.045
Eana osseana *
27th July
49.158
Hedya ochroleucana *
2nd Sept
49.289
Epiblema costipunctana *
24th July
49.307
Rhyacionia pinivorana
7th June
49.320
Dichrorampha alpinana *
20th July
62.012
Matilella (Pyla) fusca *
4th June
62.0151
Delplanqueia inscriptella *
15th July
62.021
Oncocera semirubella *
22nd Aug
62.064
Ephestia elutella *
25th July
63.042
Diplopseustis perieresalis *
21st July
63.048
Palpita vitrealis
3rd Sept
63.091
Agriphila latistria *
28th Aug
 
 
 
71.022
Maple Prominent Ptilodon cucullina
15th July
73.151
Webb’s Wainscot Globia sparganii
22nd Aug
73.215
Lesser-spotted Pinion Cosmia affinis *
24th Aug
* confirmed via dissection, with grateful thanks to Peter Hall.

Haplotinea insectella, Westcott 17th July

Diplopseustis perieresalis, Westcott 21st July

Agriphila latistria, Westcott 28th August

The three illustrated above, Haplotinea insectella, Diplopseustis perieresalis and Agriphila latistria, were all new species for Bucks.  With the expectation that I might well struggle to reach 600 species for the year (in the end something I needn’t have worried about), from September onwards particular attention was paid to searching for leaf-mines.  41 different species were identified this way in the garden, of which six proved to be new for the garden list.  For me the most interesting discovery was a vacated mine of Stigmella aceris on a fallen leaf beneath our Norway Maple.  This species is a fairly recent (1970s) colonist of the UK which is slowly spreading northwards but as yet doesn’t seem to be particularly common anywhere.  It was first recorded in Bucks during 2006 as an adult caught by the Rothamsted Insect Survey trap at Burnham Beeches.  There have been about 20 subsequent records, mostly as larval mines on Field Maple and Norway Maple and almost all from the southern half of the county.  For more about leaf-mines in the garden during 2016 follow this link.
 
Argyresthia curvella, Westcott 20th June
 
Sorhagenia rhamniella, Westcott 20th July
 
Prochoreutis myllerana, Westcott 11th August
 
Dichrorampha alpinana, Westcott 20th July
 
Prochoreutis myllerana appeared in the moth trap on four occasions between 27th July and 24th August, while on 5th September I found one resting during the daytime on a rudbeckia flower which by co-incidence was also being used by an example of its very common close relative Anthophila fabriciana (the Nettle-tap).  This made me wonder if I might perhaps have been overlooking the species in the past.  The larvae of myllerana feed on Skullcap which isn’t found in the garden although there are plenty of damp spots, ditches and ponds locally where this member of the mint family might thrive.

Maple Prominent was a very welcome addition to the garden list.  It seems to have a rather odd distribution in Bucks even though the larval food-plant Field Maple is ubiquitous.  The moth is widespread throughout the Chilterns and in the Milton Keynes area but appears to be largely absent from Aylesbury Vale and the northwest of the county.  Despite intensive trapping over the years, I’ve never found it in Bernwood Forest or any of the other associated ancient woodlands locally.
 
Maple Prominent, Westcott 15th July
 
The overall number of moths trapped in the garden during 2016 was 26,670.  That might seem a lot but it was actually a disappointing result, each of the previous three years having produced a higher total (27,438 in 2013; 32,910 in 2014; 33,941 in 2015).
 
Those macro-moth species which usually appear here in very large numbers suffered mixed fortunes during 2016.  A few ended up doing very well indeed, notably Brimstone Moth Opisthograptis luteolata, Large Yellow Underwing Noctua pronuba, Small Square-spot Diarsia rubi and Setaceous Hebrew Character Xesta c-nigrum which all achieved their highest ever garden totals.  However, rather more of them performed quite poorly compared to previous years, including Heart & Dart Agrotis exclamationis, Square-spot Rustic Xestia xanthographa, Lunar Underwing Omphaloscelis lunosa and Dark Arches Apamea monoglypha, along with the aggregate pairs of Common/Lesser Common Rustic Mesapamea secalis/didyma and Uncertain/Rustic Hoplodrina alsines/blanda.  None of the springtime Orthosia species did at all well apart from Hebrew Character Orthosia gothica, while the autumn Agrochola and Xanthia species also performed quite poorly although Black Rustic Aporophyla nigra, which flies at the same time of year, put in its best ever showing with 205 counted. 
 
Dusky Thorn Ennomos fuscantaria, supposedly one of our common species which is most under threat, was another moth which put in its best ever showing with 206 individuals seen.  Hopefully that can be sustained but the omens aren’t good due to the continued spread of the Chalara fungal disease which threatens its larval food-plant Ash Fraxinus excelsior.  Ash Die-back has already been found in my 10km square (link to map).

 
  Top 20 Highest Counts

  20   Riband Wave     275
  19   Lesser Broad-bordered Yellow Underwing      278
  18   Agriphila tristella      316
  17   Plutella xylostella      325
  16   Dark Arches      341
  15   Chrysoteuchia culmella      344
  14  Hebrew Character      345
  13   Common Footman      373
  12   Smoky Wainscot      495
  11   Flame Shoulder      533
  10  Common Rustic (aggregate)      559
  9  Brimstone Moth      583
  8   Heart and Dart      629
  7   Square-spot Rustic      699
  6   Lunar Underwing      760
  5   Small Square-spot      864
  4   Uncertain/Rustic (aggregate)     1047
  3   Setaceous Hebrew Character     1334
  2   Acentria ephemerella     1424
  1   Large Yellow Underwing     2086

 
Amongst the micros there was one very notable success story, that of Acentria ephemerella (Water Veneer) which during July, August and September amassed  a total of 1,424 individuals meaning that it came second only to Large Yellow Underwing in the year’s garden league table.  Although nowhere near those kind of numbers, Parapoynx stratiotata (Ringed China-mark) also did exceptionally well here in 2016 so the conditions locally may have favoured species whose larval stage is spent under water.
 
Acentria ephemerella, Westcott 18th September
 
Thanks to the newspapers predicting devastation of our brassica crops, Brussels Sprouts in particular, everyone will have heard about the mass invasion of Plutella xylostella (Diamond-back Moth) across the North Sea into the UK during late-May.  Westcott didn’t escape them although the final count for the year only reached 325, far fewer than many moth-trappers on the east coast achieved.  Several other micro-moth species which usually do very well here put in dismal performances during 2016.  The ‘grass moths’ were down considerably in numbers, Chrysoteuchia culmella and Agriphila straminella achieving only half of their previous year’s totals, while Agriphila tristella fell even further, down from 1,046 in 2015 to 316 in 2016.  Pleuroptya ruralis (Mother of Pearl) also put in a poor showing, dropping from 703 in 2015 to 196 in 2016.   

For migrant moths 2016 proved to be equally as good at Westcott as was the previous year, the only notable down-turn being that of Hummingbird Hawk-moth Macroglossum stellatarum which, unusually, was only recorded the once.  The table below gives first and last noted dates for those species which can be regarded as migrants here:

Plutella xylostella
325
9th May
10th October
Crocidosema plebejana
    1
2nd January
   -
Nomophila noctuella
  51
11th May
29th October
Udea ferrugalis
  43 
8th July
24th September
Diplopseustis perieresalis
    1
21st July
   -
Palpita vitrealis
    1
3rd September
   -
Vestal
    2
30th August
2nd September
Gem
    1  
6th July
   -
Convolvulus Hawk-moth
    1
28th September
   -
Hummingbird Hawk-moth
    1
27th June
   -
Dark Sword-grass
    6
9th September
14th November 
Small Mottled Willow
    1
17th August
   -
Silver Y
110
4th June
30th October
Dark Spectacle
    1
29th July
   -

Palpita vitrealis, Westcott 3rd September

Convolvulus Hawk-moth with Lunar Underwing helpfully
providing scale, Westcott 28th September

Only two of the migrant species were newcomers to the garden list (Diplopseustis perieresalis and Palpita vitrealis).  The example of Crocidosema plebejana was presumably a remnant from the remarkable spate of moth immigration which took place over Christmas 2015 when, unfortunately, we were away. I wonder what I missed!
 
Garden Tiger, Westcott 12th July
 
One of the iconic moths of my youth when, unlike now, it was common everywhere in Bucks, Garden Tiger Arctia caja had only been recorded in the garden at Westcott once since the millennium and that was back in 2009.  I was therefore very pleased to get a second visitor on 12th July 2016.  It wasn’t to end there, though, because over the next fortnight I had four more appear in the garden trap.  I really hope that this is the start of a resurgence locally although somehow I doubt it.  2016 was really more noteworthy for the regulars which didn’t turn up in the garden, including Pale Eggar Trichiura crataegi, Lappet Gastropacha quercifolia, Brindled Green Dryobotodes eremita and Old Lady Mormo maura, while only the one Red Underwing Catocala nupta was seen when their count here often reaches double-digits.