2025 saw a significant recovery for lepidoptera at Westcott after the very poor season the previous year. The number of species seen, as well as total counts of individual butterflies and moths, rose significantly and were back closer to the average. Spring 2025 proved to be the warmest and sunniest on record, while the Summer was exceptionally hot at times, although the Autumn reverted to a typically unsettled mix of wind and rain alternating with drier spells.
Butterflies
Brimstone Gonepteryx rhamni and Comma Polygonia c-album proved to be the first butterfly sightings of the year, both appearing in the garden on 3rd March, while the final one was as usual a Red Admiral Vanessa atalanta on ivy blossom on 12th October. A total of 830 individuals drawn from 23 species was recorded over the season, a significant improvement over 2024. The highest counts were provided by Red Admiral (125), Large White Pieris brassicae (105), Gatekeeper Pyronia tithonus (100) & Peacock Aglais io (99). It was noticeable that Gatekeeper in particular seemed to have a really good year in the garden, the count being more than double its previous best in 2023 when 43 were seen.
Brimstone Gonepteryx rhamni and Comma Polygonia c-album proved to be the first butterfly sightings of the year, both appearing in the garden on 3rd March, while the final one was as usual a Red Admiral Vanessa atalanta on ivy blossom on 12th October. A total of 830 individuals drawn from 23 species was recorded over the season, a significant improvement over 2024. The highest counts were provided by Red Admiral (125), Large White Pieris brassicae (105), Gatekeeper Pyronia tithonus (100) & Peacock Aglais io (99). It was noticeable that Gatekeeper in particular seemed to have a really good year in the garden, the count being more than double its previous best in 2023 when 43 were seen.
For the second year running no examples of White-letter Hairstreak Satyrium w-album were recorded here but I'm hopeful that the planting of four Ademuz disease-resistant elms will eventually tempt this species back because the butterfly is likely still using other elms around the village. While the newly-acquired trees (a variety of Ulmus minor) were still in pots awaiting planting they were being used by caterpillars of Comma Polygonia c-album so they obviously taste all right!
 |
| Comma caterpillar on elm, Westcott 17th May 2025 |
It was nice to see a couple of visits to our buddleia by Silver-washed Fritillary Argynnis paphia, the first here for five years. Another woodland species I'd really like to see again is White Admiral Limenitis camilla which made garden appearances three years running between 2005 and 2007 but there has been no sign of it since then. Marbled White Melanargia galathea and Small Tortoiseshell Aglais urticae both recovered somewhat from their dismal showings the previous year, with 10 of the former and 14 of the latter recorded, but the Small Tortoiseshell count in particular is still well below normal levels (to think that I recorded 652 of them in the garden in 2013!). Small Copper Lycaena phlaeas and Small Heath Coenonympha pamphilus are not at all regular here even though both exist in small numbers in the local area, so it was good to get counts of three and four respectively within our garden boundary during 2025. They were attracted to a small patch of ragwort Senecio jacobaea which was allowed to flourish and it was this plant which also helped produce the good numbers of Gatekeeper.
 |
| Gatekeepers on ragwort, Westcott 16th July 2025 |
The Mothing Year
As in previous years, a twin-30w actinic light was run inside the conservatory throughout the winter months and I potted up anything which came to the windows. From 20th March onwards two traps, both still using twin-30w actinic lights, were positioned out in the garden. On 22nd April one of the two actinics was replaced by a 125w MV light and that arrangement (two traps, one of them an MV and the other actinic) continued nightly throughout the year until 26th September when the MV was retired in favour of the second actinic again. Those two traps were brought in on 16th November when I reverted to running an actinic inside the conservatory.
As in previous years, a twin-30w actinic light was run inside the conservatory throughout the winter months and I potted up anything which came to the windows. From 20th March onwards two traps, both still using twin-30w actinic lights, were positioned out in the garden. On 22nd April one of the two actinics was replaced by a 125w MV light and that arrangement (two traps, one of them an MV and the other actinic) continued nightly throughout the year until 26th September when the MV was retired in favour of the second actinic again. Those two traps were brought in on 16th November when I reverted to running an actinic inside the conservatory.
Dealing first with the statistics, in January there were ten nights when the lights were not run at all (temperature below freezing by dusk) and another seven occasions when they were run but produced a nil return. Otherwise the year saw no nights missed although there were ten further nil returns in February, five more in March, one in November and five in December. At least one trap was therefore run on 345 nights and moths appeared on all but 28 occasions. The species count for 2025 came to 740 (394 micros, 346 macros) and the total number of individual moths reached 36,523, of which 24,383 were macros. No records were broken, but at least the results were back close to where they should have been after a disastrous 2024. Worth a mention here is that I don't bother recording aggregated adult micro-moths such as Yponomeuta sp, Coleophora sp or Cnephasia sp because there are just too many different species involved for that data to be of any meaningful use to anyone. I do still count them up but the totals go no further than my diary so don't appear in the statistics. However, in 2025 the aggregated total of Yponomeuta moths came to 2,403 which is quite a significant number on top of nearly 500 which were identified to species (specifically evonymella and rorrella).
There were 19 occasions in 2025 when the species count was greater than 100 in a single night, equalling my highest ever count which was set in 2019; the first of them was on 13th June and the last on 11th August. The highest count was 161 species on 30th June, although it was the previous night which produced the largest overall catch (1,528 individuals drawn from 138 species thanks to a large invasion of Water Veneer Acentria ephemerella). A further ten nights saw species counts up in the 90s so overall it was quite a good year for numbers. However it is worth mentioning that there were also several unusually poor nights during the summer of which the worst was on 1st August when only 42 moths of 22 species turned up, split between the two traps. That's the lowest count I can remember having at that time of year.
The top ten best performing moths of 2025 were Acentria ephemerella (2,051), Lunar Underwing Anchoscelis lunosa (1,537), Large Yellow Underwing Noctua pronuba (1,294), Garden Grass Veneer Chrysoteuchia culmella (1,155), Common Grass-veneer Agriphila tristella (1,114), Common Footman Eilema lurideola (1,061), Common Wainscot Mythimna pallens (825), Straw Grass-veneer Agriphila straminella (756), Scarce Footman Eilema complana (741) & Mother of Pearl Patania ruralis (638). Amongst the remainder, White-point Mythimna albipuncta (535) came in at 13th, Square-spot Rustic Xestia xanthogramma (472) was placed at 15th while the often super-abundant Heart and Dart Agrotis exclamationis (386) was way down the list at 20th.
As tabulated below, 18 species were completely new for the garden during the year, taking the all-time site list to 1,112 different moth species:
|
4.063 |
Stigmella roborella * |
11 July |
|
4.095 |
Ectoedemia atricollis * |
12 July |
|
6.004 |
Heliozela resplendella (leaf-mine on alder) |
25 Sept |
|
14.006 |
Bucculatrix frangutella (leaf-mine on buckthorn) |
30 Sept |
|
15.016 |
Euspilapteryx auroguttella |
31 May |
|
19.003 |
Glyphipterix fuscoviridella
* |
11 May |
|
26.001 |
Tinagma ocnerostomella * |
29 May |
|
35.032 |
Pexicopia malvella * |
12 July |
|
35.073 |
Monochroa palustrellus |
27 August |
|
37.026 |
Coleophora violacea * (to lure for Ni
Moth) |
29 May |
|
49.075 |
Acleris umbrana |
13 Nov |
|
49.082 |
Acleris hyemana |
26 Nov |
|
49.148 |
Apotomis lineana * |
11 July |
|
62.055 |
Homoeosoma nebulella * |
31 May |
|
65.003 |
Barred Hook-tip Watsonalla
cultraria * |
30 May |
|
70.288 |
Brussels Lace Cleorodes
lichenaria |
05 July |
|
73.048 |
Small Yellow Underwing Panemeria
tenebrata (to lure for Adoxophyes orana) |
14 May |
|
73.093 |
Clancy’s Rustic Caradrina
kadenii * |
18 Sept |
Micro-moths
It is difficult to pick out the most interesting newcomers of 2025 because they were all noteworthy in their own ways. Of the two Nepticulids, Stigmella roborella (11th July) is an oak feeder but within the garden we have only a single very young oak about 10ft tall and to date I've only found Phyllonorycter mines on it, so that individual will presumably have wandered in from elsewhere in the village. Other miners of oak confirmed as adults here during the year included Stigmella basiguttella, Stigmella ruficapitella, Stigmella atricapitella & Stigmella samiatella which are all on the garden list already, so the chances of finding corridor mines eventually on our young oak must be quite high. Ectoedemia atricollis (12th July) may have been overlooked as a mine in the garden because we have both apple and hawthorn here, its two main food-plants, so that'll be one to hunt for next season. The discovery of a small number of mines of Heliozela resplendella on our alder (25th September) will hopefully produce an adult in the trap eventually, while spotting early mines of Bucculatrix frangutella on our buckthorn (30th September) prompted more detailed searching which produced a free-feeding larva. It has since pupated indoors so hopefully should mean that I get to see the adult early next year.
 |
| Vacated mine of Heliozela resplendella on alder, Westcott 25th September 2025 |
 |
| Vacated mine of Bucculatrix frangutella on buckthorn, Westcott 30th September 2025 |
 |
| Free-feeding larva of Bucculatrix frangutella from the above mine, on buckthorn at Westcott 30th September 2025 |
Despite its nondescript appearance, Tinagma ocnerostomella (29th May) was a definite highlight because this is a species I've only ever seen previously on waste ground within the MoD site at Arncott on the border with Oxfordshire. Its larvae feed inside the stems of Viper's Bugloss Echium vulgare, a plant which favours chalky or sandy soils so is not at all common in the Vale of Aylesbury. However, I did find a small patch of it growing beside a road locally in 2024 and as a result now have some in a pot which may be what attracted the moth. On the night of 29th May I decided to place a pheromone trap containing the lure for Ni Moth Trichoplusia ni adjacent to the garden MV trap, not with the intent of catching the target species but in the hope that I'd get one of the other moths known to be attracted to that lure, Coleophora violacea. I was very pleased to find that my plan worked, with five males entering the pheromone trap and another one going into the MV trap, so maybe the moth is a bit more widespread in the county than current records might suggest. Getting two additions to the garden list a fortnight apart in November was unexpected: Acleris umbrana (13th) was a first for Bucks of a nationally scarce woodland species known from a handful of southern counties, although it could well be expanding its range because there was a record from West Berkshire during 2024, while Acleris hyemana (26th) is mainly a moorland species which wouldn't really be expected in our area although there have been very occasional past sightings of presumed vagrants with one previous record for Bucks, from the Milton Keynes area back in 2003. Another nationally scarce species, Apotomis lineana (11th July) has until now been restricted to the far north of Bucks so may also be on the move with this sighting further towards the middle of the county.
 |
| Coleophora violacea, Westcott 29th May 2025. A non-descript grey species but the white tips to the antennae are just about visible in this image. |
 |
| Acleris umbrana, Westcott 13th November 2025 |
 |
| Acleris hyemana, Westcott 26th November 2025 |
Micros which did particularly well during 2025, achieving their best ever scores here, included Scrobipalpa ocellatella (66), Coleophora alcyonipennella (122), Celypha lacunana (379), Eucosma campoliliana (35), Oncocera semirubella (29), Ostrinia nubilalis (84) & Cydalima perspectalis (82). Scrobipalpa ocellatella first appeared at Westcott in 2022 when it had a "break-out" year from its usual haunts in the sugar beet fields of East Anglia. Hardly any were seen here over the next two years but then there was a very good count in 2025 with all but three appearing during August. The clover-feeding Coleophora alcyonipennella underwent a small population explosion locally in mid-August with the highest nightly count being 32 on the 17th.
Of the four new macro-moths recorded during 2025, the rather battered and worn example of Barred Hook-tip (30th May) wasn't really to be expected here despite being fairly common in the county because its larval food-plant Beech Fagus sylvatica doesn't do well on heavy clay soils, but there are some specimen trees on the adjacent Waddesdon Estate as well as several in a plantation within Bernwood Forest. Brussels Lace (5th July) was a nice surprise, this lichen-feeding species having been absent from Bucks since the 1930s until one appeared in the Rothamsted Insect Survey trap at Burnham Beeches during 2020, so hopefully it is now re-colonising the area. The addition of Small Yellow Underwing to the garden list was long awaited because it is fairly widespread in the local area. It proved to be another success story for the use of pheromones, this time with a lure for the tortrix Adoxophyes orana which the moth is known to be attracted to. Once I was sure that Small Yellow Underwing was flying locally I put a trap out in the front garden at dawn on 14th May and when checked at 10am it had caught three males. Clancy's Rustic (18th September) seemed to have a particularly good year and was added to many garden lists as it continued its spread across the county.
 |
| Barred Hook-tip, Westcott 30th May 2025 |
 |
| Brussels Lace, Westcott 5th July 2025 |
 |
| Three Small Yellow Underwing males inside pheromone trap, Westcott 14th May 2025 |
 |
| Clancy's Rustic, Westcott 18th September 2025 |
Other macro-moths which did well in 2025 included Fox Moth Macrothylacia rubi (10) and Lappet Gastropacha quercifolia (11) which each achieved their first double-digit counts. The migrant Hummingbird Hawk-moth Macroglossum stellatarum (83) had its best year ever after a complete absence in 2024. Single-dotted Wave Idaea dimidiata (270), Shaded Broad-bar Scotopteryx chenopodiata (145) & Red-green Carpet Chloroclysta siterata (123) all achieved their highest ever annual counts, as did Yellow-tail Euproctis similis (418, which included a record 80 individuals in the traps on 1st July). Jersey Tiger Euplagia quadripunctaria continues its inexorable expansion locally with 128 seen at Westcott in 2025, up from 71 the previous year and quite an achievement for a species which was first recorded in the garden as recently as 2018. Of the autumnal species, Figure of Eight Diloba caeruleocephala (45) & Merveille du Jour Griposia aprilina (88) both managed record counts. Finally, White-point Mythimna albipuncta (535) and Turnip Agrotis segetum (299) had their longest ever seasons here as well as their best ever totals, the former between May and mid-November and the latter from April through to early December.
Mocha Cyclophora annularia, one of my favourite moths, turned up twice (12th & 17th July) having only been seen once before in the garden back in 2017. Pretty Chalk Carpet Melanthia procellata and Marbled Green Bryopsis muralis also made very welcome second garden appearances, the former on 19th June and the latter on 27th July, having first been seen here in 2013 and 2011 respectively. Plumed Fan-foot Pechipogo plumigeralis visited again on 1st October having been added to the garden list in 2024, while the smart-looking Autumnal Rustic Eugnorisma glareosa made a single repeat visit on 19th September after joining the list for the first time in 2023, so it looks as though both species may now have moved into this area.
 |
| Mocha, Westcott 12th July 2025 |
 |
| Marbled Green, Westcott 27th July 2025 |
 |
| Plumed Fan-foot, Westcott 1st October 2025 |
 |
| Autumnal Rustic, Westcott 19th September 2025 |
Migrants
Nothing really out-of-the-ordinary turned up at Westcott during 2025 but there was a very good selection of the more common migrant species throughout the summer and autumn periods, some of them appearing in good numbers. However, it came as a surprise to see how few Silver Ys visited the garden in a year when migrant activity in general was well above normal levels throughout the UK.
|
|
Species |
First |
Last |
Total |
|
18.001 |
Plutella xylostella |
12th April |
27th November |
35 |
|
63.031 |
Udea ferrugalis |
16th July |
22nd December |
34 |
|
63.048 |
Palpita vitrealis |
12th November |
14th November |
4 |
|
63.052 |
Nomophila noctuella |
11th July |
12th November |
77 |
|
69.010 |
Humming-bird Hawk-moth |
30th June |
14th September |
83 |
|
70.038 |
Vestal |
13th August |
16th October |
9 |
|
72.073 |
Small Marbled |
13th July |
- |
1 |
|
73.015 |
Silver Y |
24th May |
12th November |
12 |
|
73.074 |
Bordered Straw |
26th June |
18th August |
3 |
|
73.076 |
Scarce Bordered Straw |
8th July |
20th September |
6 |
|
73.087 |
Small Mottled Willow |
25th June |
19th August |
10 |
|
73.295 |
Delicate |
23rd August |
27th September |
8 |
|
73.307 |
Pearly Underwing |
15th November |
- |
1 |
|
73.327 |
Dark Sword-grass |
25th April |
28th November |
16 |
 |
| Small Marbled, Westcott 13th July 2025 |
 |
| Bordered Straw, Westcott 26th June 2025 |
 |
| Scarce Bordered Straw, Westcott 30th August 2025 |
No comments:
Post a Comment