Migrant insect summary - July 2012

Following a very wet June we were all hoping that the weather would perk up in July!  The first three weeks of July were dull, cloudy, unseasonably cool and very wet – all apparently due to the position of the Jet Stream.  One low pressure system after another crossed the UK bringing largely awful weather.  However it was not all bad news as around the 20th July the Jet Stream started to move back north and by the 25th southeast England became positively balmy, basking in temperatures of 30 degrees!

Odonata news was dominated by seven records of Lesser Emperor Anax parthenope which came from a private site in south Cheshire on 5 July; a male at Winterton North Dunes, Norfolk, on 9 July; a male at Lowestoft, Suffolk, on 14th; reported at Folkestone Warren, Kent, over the weekend of 21 – 22 July; a male at the Southern Long Pit, Dungeness, Kent, on 25th; a singleton at Rutland Water, Leicestershire, on 25th and finally a single at Brampton Wood, Cambridgeshire, on 28th.

Red-veined Darter Sympetrum fonscolombii were widely reported with records from the following localities during July:

Cornwall: Little Treleaver, Lizard, Cornwall on 10 July and Windmill Farm, Lizard, on 29 July.

Gloucestershire: Woorgreens, near Cinderford on 26 July with one noted in the Forest of Dean on 28 July.

Lancashire: Model boating pond at Middleton Industrial Estate, Heysham, 7 – 21 July at least.

Merseyside: Seaforth Nature Reserve on 8 & 9 July.

Kent: Sandwich Bay on Restharrow Scrape on 27 July.

Bedfordshire: Houghton Regis Quarry NR on 10 July.

Norfolk: several localities but those most viewable were up to 15 showing very well at Kelling Water Meadows.

The recent colonist Southern Emerald Damselfly Lestes barbarus was on view at Cliffe Pools, Kent, from 21 July and the more widespread Willow Emerald Damselfly Lestes viridis was widely reported from Suffolk.

The weather has been very poor for butterflies with many species emerging late and in lower than expected numbers.  As far as migrant butterflies were concerned just odd sightings of Red Admiral Vanessa atalanta and Painted Lady Vanessa cardui were made.   

July was very poor indeed for the regular immigrant moths.  Coastal stations reported catches mainly consisting of low numbers of Silver Y Autographa gamma, Dark Sword-grass Agrotis ipsilon and a very few Pearly Underwing Peridroma saucia.  Bordered Straw Heliothis peltigera were really sparse with records from Bonchurch, Isle of Wight, on the night of 1 July; Littlestone, Kent, on 4 July and from St. Osyth, Essex, on 6 July.  A Delicate Mythimna vitellina was trapped at Preston, Dorset, on the night of 3 July.  The first Convolvulus Hawk-moth Agrius convolvuli reported this year was light-trapped at Sandwich Bay, Kent, on 13 July.

Migratory micro-lepidoptera included Diamond-back Moth Plutella xylostella, Rusty-dot Pearl Udea ferrugali and Rush Veneer Nomophila noctuella recorded in very low numbers.  There was a substantial immigration of Willow Ermine Yponomeuta rorrella mainly into SE England with counts of several hundred in Kent and Suffolk.  A few penetrated further west to Dorset.  Oncocera semirubella records away from known breeding areas came from Kent and Suffolk too.  Quite a number of Evergestis limbata were also reported – most of these most likely relating to wanderers from established colonies.

Despite poor numbers of the regular and expected moth immigrants there were a few surprises which included a Stephen’s Gem Megalographa biloba on St. Mary’s, Isles of Scilly, on 13 July (M. Scott).  Incredibly this was the second record for the island – the first occurring almost ten years ago to the night!  The origin of these Nearctic moths is still open to debate – are they true transatlantic vagrants, ship-assisted or accidental imports?

The five previous records of Stephen’s Gem are as follows:

Trawscoed, Cardiganshire, 19 July 1954.

Maidencombe, Devon, 1 October 1958.

Sparsholt, Hampshire, 27 October 2001.

St. Mary’s, Isles of Scilly, 9 July 2002.

Cwm Ivy, Glamorgan, 20 September 2002.

The only other European records concern two individuals on Guernsey, Channel Islands, in August 2001.

Nowadays a resident in parts of SE England, although still an exciting catch, is the Dewick’s Plusia MacDunnoughia confusa.  In July records came from Sissinghurst Castle, Kent, on 21 July; Ramsgate (also Kent) on 26th and St. Osyth, Essex, on 27th.  Another good record from Kent was the Golden Twin-spot Chrysodeixis chalcites caught at Ramsgate on 30th by Phil Milton – the same lucky captor trapping the Dewick’s at the same locality five nights earliler.

                 

                  Dewick’s Plusia, Newington, Kent - Phil Milton

                   

                  Golden Twin-spot, Newington, Kent - Phil Milton

                 

                  Dewick’s Plusia, St. Osyth, Essex - Clive Atkins

The two recent colonists - Plumed Fan-foot Pechipogo plumigeralis and Tree-lichen Beauty Cryphia algae also put in an appearance in Kent during July.  

Other goodies have included a Many-lined Costaconvexa polygrammata at Ipswich, Suffolk, on the night of 17 July (N. Sherman) – the sixth County record with a probable immigrant Dotted Rustic Rhyacia simulans nearby at Hollesley the same night.  Also in Suffolk a Bright Wave Idaea ochrata was another ‘probable immigrant’ example at Dunwich Heath on the night of 5 July.  Records from Norfolk included two interesting pyralids – Sclerocona acutellus was a county ‘first’ recorded at Walcott on the night of 4 July and Assara terebrella recorded at Barnham Broom on 15 July was a ‘first’ for East Norfolk.  An additional terebrella was trapped at Thames Ditton, Surrey, on 30th.

                 

                  Many-lined, Ipswich, Suffolk - Neil Sherman

The highlight in Kent was a stunning Orache Moth Trachea atriplicis light-trapped at Sandwich Bay Bird Observatory on 5 July (I. Hodgson) although a Scarce Black Arches Nola aerugula was a close contender at Kingsdown on 28th (N. Jarman).

                   

                   Orache Moth, Sandwich Bay, Kent - Ian Hodgson

                   

                   Scarce Black Arches, Kingsdown, Kent - Nigel Jarman

In what has been a good season for Striped Hawk-moth Hyles livornica – further reports were received as follows:

2 July: singles at Wimbleball & Wells, Somerset.

3 July: Langport, Somerset.

4 July: Dungeness, Kent.

5 July: Ballineanig, Ballyferriter, Co. Kerry (daytime observation).

7 July: Lleyn Peninsula, Gwynedd.

                   

                   Striped Hawk-moth, Langport, Somerset - John Bebbington FRPS

                  

                   Striped Hawk-moth, Lleyn Peninsula, Gwynedd - Margery Griffin

Six records of Bedstraw Hawk-moth Hyles gallii were very well scattered with one on the Isle of Man on 7 July; one at Heysham, Lancashire, on 24th; one on the south coast at Portland, Dorset, on 26th and then three more typical east coast records from Spurn, East Yorkshire on 13th; Landguard, Suffolk, on 15th and Bempton Cliffs, East Yorkshire, on 25th.    

                    

                    Bedstraw Hawk-moth, Dhoon, Isle of Man - Ian Scott

Looking ahead August is a good month in which to catch immigrant moths like the Gypsy Moth Lymantria dispar and the Great Brocade Eurois occulta.  Other rarities could include Dusky Hook-tip Drepana curvatula or rarer still Rosy Underwing Catocala electa which has recently been expanding its European range.  If we get some easterly winds then Camberwell Beauty Nymphalis antiopa butterflies may well appear.

Atropos would like to thank you for your contributions and we look forward to receiving your migrant news on Flight Arrivals.