Butterfly Conservation HAMPSHIRE & ISLE OF WIGHT BUTTERFLY & MOTH REPORT 2013 Contents Page Introduction – Mike Wall 2 The butterfly and moth year 2013 – Tim Norriss 3 Branch reserves updates Bentley Station Meadow – Jayne Chapman 5 Magdalen Hill Down – Jenny Mallett 8 Yew Hill – Brian Fletcher 9 Dukes on the Edge – Dan Hoare 11 Reflections on Mothing – Barry Goater 13 Brown Hairstreak – Henry Edmunds 18 Obituary: Tony Dobson – Mike Wall 19 Hampshire & Isle of Wight Moth Weekend 2013 – Mike Wall 21 Common Species Summary 24 Branch photographic competition 26 Alternative Mothing – Tim Norriss 28 Great Butterfly Race 2013 – Lynn Fomison 29 Weather report 2013 – Dave Owen 30 Glossary of terms 32 Butterfly report 2013 33 Butterfly record coverage 2013 33 Summary of earliest-latest butterfly sightings 2013 34 2012-2013 butterfly trends in Hampshire & Isle of Wight 35 Species accounts 36 Moth report 2013 72 Editorial 72 Moth record coverage 2013 73 Species accounts 74 List of observers 146 Index to Butterfly Species Accounts 152 1 Introduction I have pleasure in writing this, my first introduction as Chairman of the Branch. When I joined Butterfly Conservation some ten years ago, as a new recruit to the wonderful world of moths, I never envisaged becoming part of the main committee let alone finding myself on this ‘lofty perch’! Firstly, I would like to register my and the Branch’s thanks to Pete Eeles for his support and enthusiasm for the branch during his time as chair, despite the pressures of a job that often saw him away from the country, and to the other members of the main committee for their support and enthusiasm over the past twelve months. The year since the last report was published has been a busy one for the Branch. As one of the largest branches, Hampshire and Isle of Wight has a significant part to play in the organisation, and we have been very active behind the scenes developing closer ties with central head office to improve communication, management and joint working and the branch is increasingly seen as leading the way in best practice. 2013 continued the trend of recent years in having an unusual weather pattern, characterised by a very cold winter and spring causing significant drops in recording levels for our butterflies and moths, before turning around and becoming, in the end, a true butterfly summer (amazing what a hot spell can do to short term memory!), with transect counts on our reserves reflecting both this and the significant habitat management work that has been done. Ride-widening and hedge management at Bentley Station Meadow resulted in record numbers of species such as Silver-washed Fritillary there, and Magdalen Hill Down and Yew Hill continue to benefit from scrub clearance and carefully managed grazing using sheep and cattle. We would like to put on record again our thanks to the Hampshire and Isle of Wight Wildlife Trust and the South Downs National Park Authority for their continued support, without which management of our reserves would be almost impossible. Last year’s New Members Day was as ever well attended. This is an annual event at which we invite new members to spend a day being introduced to the work of the Branch and of Butterfly Conservation as a whole and to see the Branch's flagship reserve at Magdalen Hill Down in the afternoon. This year’s event is still being planned but is hoped to be held in late summer. More details will be released in due course. The AGM and Members Day held in October saw a changing of the guard, and thanks are due to the three members who stood down, Roger Buchanan, Dave Green and Brian Fletcher, and to Pete as mentioned previously. As I write this 2014 started wet, but let’s hope it will be another good summer and enables a continuation of the recovery seen last year for our varied and diverse lepidoptera. Please visit our reserves which are the lifeblood of the branch, see the good work that is being done and if you would like to know more about our work or get involved with the work of the Branch, please contact us – without volunteers, which we all are, none of our work would be possible. Mike Wall Chair, Hampshire & Isle of Wight Branch May 2014 2 The Butterfly and Moth Year 2013 Tim Norriss 2013 was an entirely different affair from 2012, and thank goodness for that I hear you say. Many species made remarkable recoveries, most notably the Small Tortoiseshell for which four times as many records were received this year than in 2012. This belies the real scale of the increase however since the numbers seen were greater than in the last ten years. Perhaps the cold spells in February 2012 and March 2013 have affected the parasite Sturmia bella or perhaps a hyper-parasite has now had an effect. It will be interesting to see if the population now stabilises or whether it will enter a cycle of boom and bust such as that of the Holly Blue. The spring butterflies fared quite well despite the unseasonably cool weather. The Glanville Fritillary was the main exception and you can read Andy Butler’s rather depressing account of this species in later pages. We should remember though that with the right weather and habitat conditions all lepidoptera can stage remarkable recoveries, such is their fecundity. It is a shame though that for the second year running there were no reports of either Small or Pearl-bordered Fritillaries on the island and it is thought that both have been lost. Wall Brown showed a continuing decline on the Hampshire coast at Pennington but fared better on the island. When the summer arrived things took a dramatic turn for the better. The Satyrinae did well with excellent numbers of Marbled White and Speckled Wood being seen at some sites. On the 27 July Lynn and I went for a walk in Harewood Forest and the numbers of butterflies were exceptional; 400 butterflies of 17 species in an hour including 120 Silver-washed Fritillary and 65 Peacock. I don’t remember seeing such numbers for many, many years. The numbers of Chalkhill Blue flying at Arreton Down on 10 August were estimated to be around 50,000! What an amazing sight this must have been – definitely one of the seven wonders of the Isle of Wight, if not the world. Arreton Down (TJN) It is not surprising therefore that the numbers of records received went up. The number of butterfly records in 2013 went up to 79,062, a new record, and this compares to just 13,438 in 2001. In the same period the number of moth records submitted has gone from 44,763 to 123,186. This inevitably puts a strain on the process of manipulating the data, and the checking and verification required. New options for submitting your records came into effect from 1 May 2014 and are detailed on the Branch website at: http://www.hantsiow-butterflies.org.uk/recording.php The hot sunny summer saw the largest continental Swallowtail invasion since 1945 with 3 adults laying eggs in a number of gardens in Hastings, Eastbourne and Chichester. The butterflies were also seen in other south coast counties including Suffolk, Kent, Dorset and there were four sightings in Hampshire and one on the Isle of Wight. Perhaps this is the start of the colonisation of Southern England by the Swallowtail. The other migrant butterfly species to put in an unexpected appearance was the Long- tailed Blue. The first sightings were in August and continued though to October. It may well have bred in our area as it was shown to do in other south coast counties. There were migrant moths in profusion as well. Gold Spangle Autographa bractea, Sub- angled Wave Scopula nigropunctata, Feathered Beauty Peribatoides secundaria, Pigmy Footman Eilema pygmaeola and Pale Shoulder Acontia lucida were all recorded between 18 July and 2 August. There followed three Plumed Fan-foot Pechipogo plumigeralis and many Clifden Nonpareil Catocala fraxini in September. October produced reports of Uresephita gilvata, Crimson Speckled Utetheisa pulchella, and Sombre and Flame Brocades Dryobotodes tenebrosa and Trigonophora flammea. The adventive Boxworm Moth Cydalima perspectalis was found for the first time in all three vice counties. It will be interesting to see if this far-eastern species can survive the British winter and gain a foothold here. Boxworm Moth larva Cydalima perspectalis (TJN) As part of an initiative organised by Simon Curson with willing volunteers from the island to search for the scarcer autumn species that are found on the southern cliffs of the Isle of Wight in the autumn, several important records were received for the RDB Beautiful Gothic and the Brindled Ochre. Butterfly Conservation has just completed the three year project called, 'Dukes On The Edge', aimed at halting the shocking decline of the Duke of Burgundy in South East England. You can read a summary of the work carried out in the following paper by Dr Dan Hoare. 4 Branch Reserves Update Bentley Station Meadow 2013 Jayne Chapman A cold start to the spring in 2013 meant that some emerging butterfly species, i.e. the specialists, such as Pearl-bordered Fritillary, continued to suffer (not that we have many records of this species at Bentley), but the warmer weather that was to follow enabled some species such as the Large, Small and Green-veined Whites to bounce back from the terrible weather of 2012. Many species respond to habitat management, and so with the Reserve still in the restorative phase, with volunteers continuing to bring the meadow back from the brink of secondary woodland, the combination of decisive management and a warmer summer culminated in very impressive numbers of butterflies seen in 2013.