Migrant insect summary – August and September 2012
The first half of August was unsettled with frequent Atlantic depressions. High pressure then built around the middle of the month with 30 degrees widely recorded in the south. The highest maximum day-time temperature recorded was 32.4 degrees at Cavendish (Suffolk) on 18 August. Southerly winds around this time produced the best mothing conditions of the year so far with some very exciting captures indeed.
September continued warm with above average temperatures for the first fortnight – 28 degrees being recorded in the south on 9 September. Temperatures in the latter half of the month were closer to the historical average in the high teens. The winds were mostly westerly and south-westerly. Torrential rain arrived mostly in northern England following a northerly and then easterly airflow from 23rd to 25th.
Dragonfly news in August included Southern Migrant Hawkers again this summer at several sites around the Thames in Essex and Kent; following the species first appearance there in 2010. At least one male remained at Rainham Marshes (Essex) until 4 September. Lesser Emperors appeared along the south coast in Devon, Dorset, Hampshire, Surrey, East Sussex and Kent; up the east coast to Suffolk and inland to Cambridgeshire.
There were widespread reports of Red-veined Darter during the period with up to 50 noted at Severn Beach (Gloucestershire) in late August. Late records concerned a female seen in Hampshire on 29 September and 25+ still at Windmill Farm (Cornwall) on the same date.
Damselflies included Southern Emerald Damselflies reported from Cliffe Pools (Kent) and Winterton North Dunes (Norfolk) – both sites held the species in 2011 too. The other recent colonist, the Willow Emerald Damselfly continues to spread its range with many reports from new sites. Records came from Suffolk, Essex, Norfolk and Kent with the species recorded near Biggleswade (Bedfordshire) on 27 August – the first County record and in Cambridgeshire on 8 August.
Exciting butterfly news was the appearance of three Monarchs. The first was noted at Ventnor Downs (Isle of Wight) on 3 September with another remaining for a week on the south coast at Easton, Portland (Dorset) from 7 – 15 September. This latter individual remaining on view for this length of time was a popular twitch, with many visitors coming to see the butterfly and combining their visit with a viewing of a Short-billed Dowitcher at Lodmoor, in nearby Weymouth. The Monarch was frequently seen nectaring on Buddleia and occasionally Runner Bean flowers. During cool, dull periods it would roost high up in nearby trees. The third Monarch was noted at Flamborough Head (East Yorkshire) on 13 September – an exceptionally rare east coast record.
Monarch - Ventnor Downs (Isle of Wight) - Andy Butler
Camberwell Beauties appeared on cue as predicted in the previous summary! The first during the period was at Sissinghurst, Kent, on 11 August with two further records in September at Hayle Estuary (Cornwall) on 2nd and at Fareham, Hampshire, on 12th. A Long-tailed Blue of unknown origin was at the East India Dock (London) on 10 August.
A significant influx of both Red Admiral and Small Tortoiseshell was evident nationwide with some coastal stations reporting catches in their moth traps. A high count of 1000 Red Admirals was made at Ticehurst (East Sussex) on 13 September – the butterflies feeding on plums. Painted Lady and Clouded Yellow were notable by their scarcity although a dozen of the latter were in Bournemouth (Dorset) on 15 September.
Significant moth news in August was of the appearance of no fewer than five of the attractive Shining Marbled. With only one previous British record (from Herefordshire in 2006 and thought possibly to have been an accidental importation) this was big news! Three moths arrived on the same night of 19 August: at Downgate (Cornwall) (Mary Atkinson), Worthing (East Sussex) (Mike Snelling) and Dymchurch (Kent) (John Owen). News later surfaced of a further individual at Chardstock (Devon) caught on 18 August (Alan Jenkins).
Shining Marbled - Downgate (Cornwall) - Mary Atkinson
Other major moth news included a fine example of The Latin caught at Bracklesham (West Sussex) by Derek Lee. This exotic-looking moth was only the fourth British mainland record and first for 11 years. All records have been from the English south coast.
The Latin - Bracklesham (West Sussex) - Matthew J. Deans
Previous British records of The Latin:
Higher Hyde, Dorset, 7 July 2001
Wye, Kent, 27 July 1962
Laughton, Sussex, 16 May 1959
Tamarisk Peacock added to the British list as recently as 2004 appeared again this year with a record from Bexhill (East Sussex) on 18 August (Derek Crawley). This potential future colonist has only made it to our shores on about seven occasions.
Tamarisk Peacock - Bexhill (East Sussex) - Derek Crawley
The almost-mythical Three-humped Prominent was the East Anglian highlight from this exciting period when a male appeared at Matthew Deans’ trap in the grounds of Bawdsey Hall (Suffolk) on the night of 18 August. Since 1900 there have only been about fifteen previous British records of adults.
Three-humped Prominent - Bawdsey Hall (Suffolk) - David Hermon
Following the July record of a Stephen’s Gem from Scilly a forewing of another was discovered below a bat roost at Luckett (Cornwall) – constituting the seventh British record.
Immigrant hawk-moths during August and September mainly concerned the enormous Convolvulus Hawk-moth which was widely recorded – perhaps around 70 were recorded with three caught in a single night at Durlston CP (Dorset) the highest single count. A larva of Death’s-head Hawk-moth was discovered on 20 August near Hastings (East Sussex). Another half a dozen Bedstraw Hawk-moths were recorded during the period.
Bedstraw Hawk-moth - Bawdsey Picnic Site (Suffolk) - Matthew J. Deans
Rare geometrid moths during the period included two Dusky Hook-tips in Kent (at Sissinghurst and Saltwood on 19 and 20 August respectively). Around half a dozen Blair’s Mocha were reported including an excellent inland record from Kenilworth (Warwickshire) on 20 August. Jersey Mocha records continue to increase year on year and at least ten were light-trapped during the period. Vestals were recorded in reasonable numbers along with a few Gems. Probable immigrant Rest Harrows were recorded at Bradwell (Essex) on 17 August and from Dungeness (Kent) on 4 September.
The Oak Processionary was recorded away from the known breeding areas as a probable immigrant during August at Hemsby (Norfolk) on 12th, Dungeness (Kent) on 18th and at Bradwell (Essex) on 20th. The other seemingly unpopular moth – the Gypsy Moth – was recorded away from its known breeding haunts in Portsmouth (Hampshire) and on Thanet (Kent).
After the high number of Crimson Speckled records in the 2011 season the only one seen this year was one typically found by day at Chesil Beach (Dorset) on 26 September by Dave Foot - who successful bred the moth last year. Similarly after a record year in 2011, the only Small Marbled so far this year was at Bawdsey Hall (Suffolk) on the night of 26 August – a county ‘first’. The appearance of a dozen Beautiful Marbleds on the south coast and East Anglia was another feature of the mid-August heatwave; with two records each from both Kent and Suffolk.
Small Marbled - Bawdsey Hall (Suffolk) - Matthew J. Deans
Rare plusias arriving included two different individuals of Slender Burnished Brass on the Lizard (Cornwall) on the nights of 26 and 29 September (Mark Tunmore). Golden Twin-spots were only recorded from Kent (Densole on 15 August and Ramsgate on 5 September). About six Dewick’s Plusia were reported.
Slender Burnished Brass - Lizard (Cornwall) - Mark Tunmore
Dewick's Plusia - Bradwell (Suffolk) - Keith Knights
Pale Shoulder is a beautiful moth with only about 25 previous records prior to this season. This year produced two further records on the 19 August from Bexhill (East Sussex) and well inland from Kensworth (Bedfordshire). It is surprising this moth is so rare here as it is a widespread and sometimes common moth in southern Europe.
Scarce Bordered Straw and Bordered Straw were recorded in very low numbers during August and September with many coastal stations missing out on records of these species. A Marbled Grey at Sandwich was a typical ‘Kentish record’ on 12 August. Small Mottled Willow had a poor showing with less than ten reported to ‘Flight Arrivals’. Numbers of Porter’s Rustic are subject to fluctuation too – five were reported during the period. Following the Orache Moth last month in Kent; one was at Freshwater (Isle of Wight) on 17 August. The striking Purple Cloud was trapped at Densole (Kent) on 7 August – this county providing the majority of records of this species.
Following an excellent autumn for Pale-lemon Sallow in 2011; just a handful were reported this year as suspected immigrants. This first of the year was recorded from Hemsby (Norfolk) on 13 September.
The regular immigrants Delicate and Cosmopolitan only reached single-figure counts during August and September and Pearly Underwing only tallied about 15 individuals reported. A single suspected immigrant Portland Moth was caught at Sandwich Bay (Kent) on 16 August. The sole record of Great Dart this year was at Sandy Point (Hampshire) on 17 August and the only Great Brocade of immigrant origin was at Hollesley (Suffolk) on 13 August.
Immigrant micro-lepidoptera included the fleabane-feeding Tebenna micalis seen near Falmouth (Cornwall) during August and a single at light at Bawdsey Hall (Suffolk) on 4 September – this one representing the first for Suffolk and East Anglia.
Tebenna micalis - Bawdsey Hall (Suffolk) - Rebecca Nason
However it was Cydia amplana that broke all records! An unprecedented influx of this tiny orange tortrix took place during August with widespread records – perhaps as many as 700 individuals were recorded. The highest counts came from Portland (Dorset) with 107 on 17 August and 83 from Alderney (Channel Islands). One at Lealholm (North Yorkshire) on 16 August was a county ‘first’.
Rare immigrant pyralids included an example of Diplopseustis perieresalis at Tiverton (Devon) on 2 September and single Duponchelia fovealis found in the classic way indoors in Hampshire and County Antrim. Approximately 15 Loxostege sticticalis were reported and half a dozen Acrobasis tumidana.
'Atropos' thank you for your contributions and we look forward to receiving your migrant news and photographs for future migrant summaries and publication in the journal. Hopefully October will produce a few surprises; maybe some Red-headed Chestnuts and it will be fascinating to see where Black-spotted Chestnut turns up this autumn – will records be restricted to Kent or has the moth already spread?