Migrant insect summary - October to mid-November 2012

The weather during October was dominated by Atlantic low pressure systems; these producing mild conditions and predominant southwesterly airflows, with some quite heavy downpours at times.  Around the third week of October, easterly winds provided some interesting moth records; most notably in East Anglia and the South-east.   During the last week of October and the first week of November an Arctic blast ensued, with many moth-ers thinking about packing their traps away for the season, as catches dwindled.

Dragonfly sightings during October included a very late male Lesser Emperor seen perched on gorse near the cliff edge at Tennyson Down (Isle of Wight) on 6 October.  Red-veined Darter records came from Lower Pennington and Badminston Gravel Pits (both Hampshire) during the first week of October with a male and female noted at Windmill Farm (Cornwall) on 22nd of the month.  A very late Southern Hawker was noted at West Hill (Devon) on 13 November with a Migrant Hawker at Weybourne (Norfolk) on 18 November.  Common Darters were widely reported up until at least 18 November. 

Damselflies included four Willow Emerald Damselflies still at Alton Water (Suffolk) on 13 October.  An exceptionally late Beautiful Demoiselle was seen at Kenidjack Valley (Cornwall) on 30 October.

Following the August record of a Long-tailed Blue in London; another was seen on 30 October at Leigh-on-Sea (Essex) (Don Down).  Found indoors, this butterfly had presumably emerged from locally bought imported produce from a supermarket.   There were no reports of Monarchs during October; which was perhaps surprising given the fact that three were seen in September.

Impressive numbers of Red Admirals were counted in Hampshire in the first week of October; with 218 on 4th and 280 on 7th.  The majority of these butterflies were nectaring on Ivy (Dr David Tinling).   Clouded Yellows barely made it into double figures during October and Painted Lady butterflies remained scarce too.

The most significant moth news during the late autumn period was of the third Stephen’s Gem of the year light-trapped in Northern Ireland on 7 November.  Andrew Crory discovered the moth at the well-recorded Murlough NNR near Dundrum (Co. Down).  It was a ‘first’ for Ireland and there are only seven British records to date (including the two earlier this year).

Stephen's Gem - Murlough NNR (Co. Down) - Dave Allen

The other major news has been appearance for the second consecutive autumn of the Black-spotted Chestnut in Kent.  The first of the autumn was found on 7 November at New Barn whilst clearing out a greenhouse (Peter Heathcote).  Up until mid-November five moths have been reported in the New Barn and Dartford areas. 

Black-spotted Chestnut - New Barn (Kent) - Sean Clancy

Red-headed Chestnuts have been scarce this autumn with one at Minsmere RSPB reserve, Suffolk, most noteworthy as it was a ‘first’ for this well recorded reserve when one was trapped on 19 October (Robin Harvey).  At least two others were reported from undisclosed localities in Sussex during the period.

Red-headed Chestnut - Minsmere RSPB Reserve (Suffolk) - Robin Harvey

Completing the hat-trick of Eublemma species for Suffolk in 2012 (following a Small Marbled at Bawdsey Hall and Beautiful Marbled at both Leiston and Landguard earlier in the season); a Purple Marbled at Minsmere on 24 October was not only another ‘first’ for the reserve but represented the 1,100th species of Lepidoptera there (Robin Harvey).

Purple Marbled - Minsmere RSPB Reserve (Suffolk) - Robin Harvey

Records of immigrant hawk-moths during October concerned maybe fifty each of Convolvulus and Humming-bird Hawk-moths.  A record of convolvuli from Woodnewton (Northants) on 4 October was an excellent inland capture (Nick Smith).  There were no records of adult Death’s-head Hawk-moth in what is usually a good month for the species.  A belated larval record concerned one located at Widford (Herts) in mid-September.

Scarce geometrid moths during October and early November included reports of Blair’s Mocha from south coast localities – some of these certainly relating to moths from established populations.  Around 40 Vestals were reported which included a high count (in Suffolk terms) of five from Dunwich on the night of 23 October (David Brown).  There was a significant influx of Gems with numbers about three-fold of the Vestal tally.

Just a single Golden Twin-spot was recorded in October – at Sandwich Bay (Kent) on the 24th.  About eight Dewick’s Plusia were reported during October and a late Ni Moth was at Bracklesham (West Sussex) on 13 November (Derek Lee).

Around 60 Scarce Bordered Straw were recorded in October and mid-November.  Singles well inland at Bettisfield Moss (Shropshire) on 23 October and Ryton Pools (Warks) on 22 October were particularly noteworthy.  A small mid-October influx of Small Mottled Willow was evident with two at Bawdsey Hall (Suffolk) on the night of 23 October.  A Pale-lemon Sallow found whilst pulling up old Nicotiana at Saltwood (Kent) on 8 October was an unusual record (Paul Howe).

Three-figure counts were made of Delicate during the period.  Cosmopolitan reached double figures with records from the Isles of Scilly and Alderney.  Most of the White-speck recorded were also from Scilly where the species is probably resident.  Pearly Underwing and Dark Sword-grass were recorded in moderate numbers.  An Oxfordshire record of a Pearly Underwing from Benson on 8 October is particularly noteworthy (Marc Botham).

Of the recent colonists Flame Brocade were recorded in good numbers in Sussex and were a regular feature of trapping on Portland (Dorset).  Oak Rustic was recorded for the first time in East Sussex (at Bexhill-on-sea on 24 October) – (Keith Alexander) and for the second time in Kent (St. Margaret’s on 12 November (Tony Morris).  The species also appeared at Ferring (West Sussex) on 13 November representing the first site record (Tim Freed).

Oak Rustic - St. Margaret's at Cliffe (Kent) - Tony Morris

Sombre Brocade appeared on the Isle of Wight at Bonchurch on 14 October (James Halsey) representing a ‘first’ for the island.  Only about 15 Clancy’s Rustics were reported – a poor showing compared to recent years.  It was also a poor year for the Clifden Nonpareil with maybe a dozen noted during the month wandering from established populations.

Rare micros included the third British record of the presumed adventive Antipodean pyralid Musotima nitidalis at Harlow (Essex) on the night of 13 November (Paul Trigg) which followed hot-on-the-heels of last year’s record at Crawley.  The species was only added to the British list as recently as 2009 when one was recorded in Dorset.  The larvae feed on the underside of fern fronds.

Other interesting pyralids included the ‘tropical’ species Spoladea recurvalis at Portland (Dorset) on 8 October (Martin Cade) and Antigastra catalaunalis at Bawdsey Hall (Suffolk) on 23 October (Matthew Deans). 

Antigastra catalaunalis - Bawdsey Hall (Suffolk) - Rebecca Nason

Palpita vitrealis records tallied around 16 with two of these the same night at Dunwich (Suffolk) on 24 October (David Brown) and a first site record from Highworth (Wiltshire) on 23 October (Steve Nash).  Numbers of Rusty-dot Pearl remained low but there was a considerable influx of Rush Veneer.

Thank you for your contributions and we look forward to receiving your migrant news on Flight Arrivals, even of the commoner immigrants as the season draws to a close.  The remainder of November and into December will hopefully produce further records of the Black-spotted Chestnut too.