Suffolk Argus 38 Summer 2006 by Suffolk Naturalists' Society

Suffolk Branch Contacts President

Howard Mendel, do The Natural History Museum, Cromwell Road, London, SW7 5BD (0171 938 8782) Chairman

Mike Dean, Coach House, lxworth, Bury St. Edmunds, Suffolk IP3 l 2HL (01359 230292)

The Butterfly Conservation Conservation Officer (Butterflies}

Rob Parker, 66 Cornfield Road, Bury St. Edmunds, Suffolk IP33 3BN (01284 705476) Conservation Officer (Moths)

Tony Prichard, 3 Powling Road, Ipswich, Suffolk, IP3 9JR {01473 270047) County Recorder (Moths)

Membership Secretary

Tony Prichard (address above}

Beryl Johnson, 28 Medway Road, Ipswich, Suffolk IP3 0QH (01473 715701)

Tony Prichard, (address above)

Newsletter Editor

(Vacant} Publicity Officer (Vacant) Programme Secretary

Alan Johnson, 28 Medway Road, Ipswich, Suffolk IP3 0QH (01473 715701) County Recorder (Butterflies)

Secretary

Treasurer

Jim Foster, Lugano, The Street, Stonham Aspal, Stowmarket, Suffolk IP14 6AH (01449711484) Regional Officer Eastern Region

Sharon Hearle, do Busy Bee, 21 High St., Newmarket, Suffolk CBS 8LX (0 1638 731648) sharon@butterfly-conservation.org

Rob Parker (address above right) Committee Members

Stella Wolfe,

Volunteers Needed

ekeeper by BerylJohnson

If you feel you could help out now and then with the growing work of the Branch, please contact Beryl Johnson on 01473 715701.

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The Newsletter of the Suffolk Branch of Butterfly Conservation

Published by the Suffolk Branch of Butterfly Conservation www.suffolkbunerflies.org. uk Butterfly Conservation Limited by Guarantee Registered Office: Manor Yard. East Lulworth, Wareham, Dorset BH20 SQP Tel: (01929) 400209 © 2004 all rights reserved Reg. No. 2206468 Reg. Charity No. 254937 Editor. Stuart Gough Logo: (Silver-studded Blue) Doug Hammersley Design: Stephen Ion, Cat & Mouse design Printer. 321 Priming, 25 Brookhouse Business Park, HaclJeigh Road, Ipswich, Suffolk IP2 0EF

Butterfly Conservation

Summer 2006 Volume38

Summer2006

The Suffolk Argus

Contents

§Jat,~f;~ps

Editorial

Editorial Graylings in Suffolk 2005 Butterfly Report Annual Report on Silver-studded Blue 2005 Dingy Skipper Survey 2005 Early and Late Records Update Hot Spots for Butterflies My Net Reaction When did you last see a Wall Brown or Small Heath Open Gardens Poster Newsletter Details and General Information Suffolk Branch Contacts

3 4 6 8 11 14 15 16 17 18 19 Back Cover

For that difficult to find present, why not give a decorative butterfly or moth lo mount on the front wall of someone's home ?

Copy Dates Contributions for our newsletter should reach the Editor {address on back page) no later than:

Spring

Christmas Eve

Summer

April Fools Day

Autumn

August Bank Holiday Cast in aluminium and enamelled in very realistic colours at five times life-size,they will last for many years. Highly individual nameplates too, to your own design, with no-obligation colour preview. Suffolk Branch will receive one quarter of the purchase price.

Any piece of writing that is considered to be of interest will be published together with line drawings/prints /photographs. The Suffolk Argus is your magazine, so please let us hear from you.

To advertise in the Suffolk Argus please contact Mike Dean on 01359 230292.

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MOTHGROU

For that difficult to find present, why not give a decorative butterfly or moth to mount on the front wall of someone's home ? Cast in aluminium and enamelled in very realistic colours at five times life-size,they will last for many years. Highly Individual nameplates too, to your own desigo,with no-obligation colour preview. Suffolk Branch will receive one quarter of the purchase price. Phone or fax Mervyn Crawford on Mildenhall (01638) 712600 for Colour imichi.trel

Phone or fax Mervyn Crawford on Mildenhall (01638) 712600 for Colour brochure I Price list

Pric'e list

Come and see the wonders of the night. Regular field meetings and newsletter. Online guide to the larger moths of Suffolk. Website: www.suffolkmoths.org.uk Contad: Tony Prichard for further details. 19

The Suffolk Argus

Summer2006

Save our Butterflies Week 22-30 July

Open Garden for Butterflies & Moths Sat 29th July At "PriorsOak" Leiston Rd, Aldeburgh 10:30 to 12:30

Editorial by Stuart Gough

Programme Amendment

A slightly reduced Argus comes to you this summer, an edition that whilst containing no field meeting reports, it does cover last years butterfly season in some depth. This is down to the Annual Report and some of its annexes, as provided by Rob Parker. As you will see, the majority of the copy for this journal has been written by Rob, my thanks to him for coming up with the goods during the quiet months. Adjacent to this editorial you can find an amendment to the 2006 Field Meetings, passed to me by Alan Johnson, our Programme Secretary. I have regrettably had to stand down from the editor's role, with only two editions completed. Largely due to the fallibility of it being easier co say yes than no, when asked to take on the job in the first place. Consequently Mike Dean has asked for any volunteers, with both the time and willingness to take over the job, to contact him (details on back page) for details. •

Will any members planning to attend the meeting on Sunday July 23rd (North Downs) please note the following changes:Meet at car park of Dorking Railway Station, northeast outskirts of Dorking, just off the A24 going cowards Leatherhead. Map reference TQ 171503 (Landranger 187) Time 10: 15 prompt, as it is intended co catch the 10:45 train from the nearby Dorking Deepdene Station to Betchworth (tickets can be obtained on the train).

An open invitation to visit Trudie Willis' wildlife garden - 10 acres including a Buddleia and Honeysuckle collection. Experts will be on hand to point out what is flying and to show moths attracted to mercury vapour lights.

Priors Oak lies one mile north of Aldeburgh on the B 1122, on the left.

www.suffolkbutterflies.org.uk 18

Summer2006

The Suffolk Argus temperature has risen to the 30°C necessary for flight, it will either fly, or turn around until its body and wings are facing directly into the sun minimising heat uptake from then on. The cryptic markings on the hindwings are all that remains to be seen when the forewings are folded back, and the orange patch around the apical eyespot is· lost from view. Against sand, gravel or dead wood, the butterfly is extremely difficult to spot, even if you saw accurately where it landed; only when it flies off at your approach, does it become visible again. Taking nectar in the sun, it is less cautious, and may even open its wings partly, so look on the heather blossom for best results. Sometimes described as human friendly, they do seem to take an interest in passing humans, and bright T-shirts are said to attract them. A male alighted on Alex's pink blouse in the King's Forest this summer, and stayed for several minutes whilst I tried to focus the camera. What I did not see this year in West Suffolk, was any quantity of Graylings. In the recent past, I have found a dozen or more at a couple of spots on Lakenheath Warren, but this year it was just singles. I suspect that their distribution is polarising towards the Sandlings and the Brecks, leaving a bigger gap in the middle of Suffolk than is shown in the maps of Richard Stewart's The Millennium Atlas of Suffolk Butterflies - a visible change even over a 5-year period. [See map opposite for the latest picture) It has not been seen at Wortham Ling for some years, and our 2005 field visit sought to discover whether it was still present, but sadly failed to prove that it was. Late in summer, the females visit clumps of grass and lay eggs singly, usually on a dried brown sheath, rather than on a growing blade. On one of our field trips a couple of years ago, some members were lucky enough to watch one laying an egg on apparently dead grass on the margins of Sizewell Beach. The larvae hatch in autumn, but do not feed much before hibernating, still as tiny caterpillars, at the base of a tussock. When fresh grass begins to grow in spring, they start to feed in earnest, climbing up the stems at night to eat the growing blades out of sight of predators. Moth

Graylings • in

Suffolk

by Rob Parker The Grayling is the largest British member of the butterfly family of"Browns", and one of the scarcest. We are lucky to have it in Suffolk, although our populations are harder to find than they used to be. ff you are interested in seeing them, read on. Grass sounds like an easily found larval host plant, but the Grayling is rather particular about the sort of grassland it frequents. It needs welldrained sandy soil, preferably slightly acidic. A glance at the UK distribution map in the Millennium Atlas of Butterflies in Britain & Ireland shows that it is found at mainly coastal sites, and hardly inland at all. The Suffolk Brecl<landprovides something of an exception, as the soils here are very sandy, and akin to the Sandlings which is our most extensive habitat. The individual grass species vary from Marram on the dunes to Sheep's Fescue on heathland, but lush green fertilised pasture is totally unsuitable. Sandy soils often support conifers, and the Grayling is happy along the edge of the forest at Tunstall or Thetford, where sparse grass sprouts along the side of a stony track. Such a place often has heather too, which is the Grayling's favourite source of nectar. The adult is on the wing in a single brood, from mid July through August, and well into September. Often there is a mass of heather at that time, but very little other blossom on the heath. It flies strongly, and often lands on the path a few metres ahead of you, only to disappear instantly; so effective is the camouflage of its undersides. Temperature regulation appears to be particularly important for the Grayling, and it basks not wings open like most species, but wings tightly closed and inclined away from the sun to catch the maximum heat on its undersides. When its body

When did you last see a Wall Brown or a Small Heath?

to find over a longer period. In the Millennium survey, the Wall was recorded from 32% of Suffolk's 1089 tetrads, and 5 years later it was found in only 23% of the 855 tetrads surveyed. In 2005 it was recorded from only 6%, making it almost as scarce as our Biodiversity Action Plan species. The decline of the Small Heath follows a similar pattern, with 33% in the Millennium survey falling to 22%, and the last two single years hitting 17% and 20% rather less worrying than the Wall. Attention is drawn to this situation to encourage butterfly watchers to keep a special eye out for both Wall and Small Heath. Past records being often only a tick, do not throw much light on the strength of a population, so please do record numbers and comment on habitat quality when possible. Even approximate estimates of 5, 20 or 30 plus are helpful for Small Heath, once assumed to be present in hundreds, whereas Walls are more likely to be in ones and twos, •with anything over 6 being quite noteworthy. We have created a large colour sheet to catch the attention of casual recorders, and this will be deposited in country parks and forest centres, as well as being distributed to SWf branches. If you are ready to assist by distributing these to suitable places, please contact Sharon Hearle on 01638 731648. By the time you read this, the first brood will be over, but you can make a diary note to look for the second. Sightings can be sent to Rob Parker at: butterflies@sns.org.uk

by Rob Parker ff you live in central Suffolk, the chances are that you have not seen a Wall for some years, and you may have to think bard to remember whether you actually saw any Small Heaths last year. But both are what :we think of as widespread butterflies, and the Small Heath used to be really common. Sadly, both are in . decline, and this merits a bit of attention. They belong to the same family (the Satyridae, or "Browns"), and are both doublebrooded, their larvae both feed on grasses, but only in particular habitats. Both are declining, and their distribution patterns are similar, with good cover near the coast, reasonable colonies in the Brecks, and a widening void in the agricultural- areas in. between. The trend is towards the even thinner distribution pattern of their cousin the Grayling. The thin soils of the Sandlings support the right sort of grassland for the Wall, and our heaths are places where the Small Heath still flies in good numbers over sparse Sheep's Fescue, but the high nitroge_n grassland of fertilised "improved" grassland that now dominates in mos_t places is useless. Members in the west have a good chance of spotting Walls sunning themselves on the bare soil in the shelter of the banks along the Lark or the Little Ouse. May is a good time to be on the look out for the first broods, with the larger second broods reaching their peaks in August, and a few late emerging insects still on the wing well into autumn. The Wall is rather short-lived, and you have to be there during the right few days, whilst the Small Heath, being more numerous, is easier

,...-:'"

by DouglasHammersley

Summer2006

The Suffolk Argus

Grayling by Douglas Hammersley

My Net

Reaction by Wilfred George. In 1930s, butter-muslin was too thick - so left me puzzlin'. Mosquito-net, in 1940s dari.fied our bug-hunt sorties. I'd found the common butterflies and so it was no great surprise that hover-flies became my quest and my over-riding interest. For these I use a smaller net which folds up, so that I can get it in my pocket, out of view, where it does not upset those who might think I'm netting butterflies exterminating some rareprize. Yet, if I say I'm catching flies, then no-one minds how hard one tries. But what's the difference? Why applaud a hunter of a different Order?

And then that golden flash goespast swooping round - and much too fast. Reminiscent of a bomber W'lisit Painted Lady? - or a Comma? Identity mistakes get made when specimens are worn and frayed. Richard and I displayed this failing took Painted Lady for a Grayling. So even with my half-sized net it's worth a try, in hopes we get one more speciesfor the list which (if netless) we'd have missed.

Grayling records 2000 to 2004 inclusive.

men searching fescue for Lunar Yellow Underwing larvae at night do find Grayling larvae at sites like Rendlesham Forest. Late in June they pupate in a silk-lined cavity at ground level, awaiting emergence some hot day in July. So, if you want to see Graylings, make a note in your 2006 diary now. In the west, visit Cavenham Heath NNR, the King's Forest, Lakenheath Warren (the public bits) or even Ramparts Field. Towards the coast, there is a wider range of opportunities around Minsmere, Dunwich and Sutton Hoo, to name but a few. Go on a fine day in July or August, and look out for patches of heather. Remember that Meadow Browns will be on the wing, and watch them first, noting their size and the appearance of their underwings when settled on the ground. When something larger flies by more strongly, watch it carefully - it could be Hipparchiasemele. And if it is, then be sure to note the date and precise location. The County Butterfly Recorder is waiting for your records! (butterflies@sns.org.uk ).

Note the polarisationtowardsthe sandy areasof the Brecksand the Sandlings. Found in a total of I 08 tetradsover thefive yearperiod.

Written Autumn 2005

Key: • 1 sighting • 2-9 max seen • 10+ max seen

Then the restlessClouded Yellow never stops - athletic follow. W'lisit he/ice?- Berger's?- Pale? Could befemale - could be male. These three species make my case to be readyfor the chase. And Richard is, at heart, we know it just one more, bug-hunting poet.

Now if I see a butteifly, I'm still excited - and try to note its species, and its sex, which may require (in practice) nets. Some types, like Graylings, closetheir wings at rest, which means the bloomin' things all look the same until they flutter {which must make other Graylings mutter.)

The Suffolk Argus

Summer2006 numbers were not down by as much as casual observation led one to think. Overall then, 2005 has been notable only for a handful of unusual sightings; generally it has been a year of low butterfly numbers.

2005 Butterfly Report

Weather Average temperatures were again about a degree up on historic averages, but sunshine was only average. Rainfall was low initially, but it was wetter than average in the summer. The table below shows mean temperature, sunshine for and rainfall for East Anglia, all presented as anomalies compared to averages over the period 1961 to 1990. Spring warmth opened the season nicely, but some very wet days inhibited recording activity in summer. Autumn was warm and extremely sunny; sadly there were very few butterflies on the buddleia, but there were plenty of Red Admirals well into November.

by Rob Parker 2005 was the hottest year the Northern Hemisphere bas ever experienced, according to climatologists. However, the Suffolk weather was not hot compared to 2003, and was sufficiently erratic to spoil the butterfly season for some species, with heavy rain at unwanted moments. It was an ordinary year for our commonest residents, a depleted year for the Vanessids and an unusually poor year for migrants. The progressive decline of Grayling and Wall Brown continued, and most observers commented on a boring, poor, unexciting or disappointing season. Fortunes were mixed for our scarcer species, with encouraging records from fresh sites for White Admiral and White-letter Hairstreak, ups and downs for Dingy Skipper and a big down for the Silver-studded Blue at Purdis Heath. A couple of rare aberrations were found in the wild, and further excitement resulted from the discovery that Purple Emperor was flying in Suffolk (following releases made in earlier years). Meanwhile, counts from transects showed that

Monitoring the BAP Species This year's Dingy Skipper survey got off to an excellent start, with a record count at the Wordwell/King's Archery colony, but a worrying count of just one at RAF Barnham, where grazing by sheep has just been introduced. The Silver-studded Blue survey was blighted by a false start and heavy rain, resulting in incomplete counts at the Minsmere sites. Results elsewhere were mixed, with two newly colonised sites apparently in good health, but a very worrying deterioration at Purdis Heath, where no one saw more than 6. The White-letter Hairstreak was again rather well recorded in 2005, with 9 sightings from

Tortoiseshell, Meadow Brown, Ringlet and Gatekeeper. I counted over a hundred Gatekeepers in 2004. The sunlit path attracts Wall, Painted Lady and Grayling, while Holly Blue is usually present higher up. Also in the trees, depending on the time of day, are Purple Hairstreaks. An unofficial path rakes you right to Thorpeness, with a comfortable seat recently placed to give extensive views across the North Warren reedbeds. A right turn at the cottages takes you past buddleias, the edge of the Meare, across the golf course, past the windmill and House in the Clouds then a final few hundred yards of good butterfly habitat on the left before you emerge in the middle of Thorpeness. Now you are not far from the area that attracted unprecedented numbers of Queen of Spain Fritillary in 1997 and being so dose to the sea there is always the chance of migrants - Swallowtail has also been recorded nearby. Returning to the original path along the railway line, the sheer number of butterflies that is so memorable on a hot, sunny summer's day. Hallway along a right turn continues the circular walk, mainly through conservation fields with Small Copper, Small Heath and Brown Argus likely species, plus Common Blue that can also be seen on the protected shingle beach facingyou as you emerge at Sluice Cottage. Also, returning to Aldeburgh, check closely on all the stands of flowering Valerian growing in the shingle beach. The plant is good for migrant butterflies and on August 31st 2004 my total count was 36 Small White, 24 Painted Lady, 3 Clouded Yellowand 96 Small Tonoiseshell.

Hot Spots for

Butterflies: Aldeburgh to Thorpeness by Richard Stewart. This can either be a circular walk or you can go right through to Thorpeness. It is best for butterflies when the bramble is flowering but if you go earlier you could add Orange Tip, Green Hairstreak and possibly Brimstone to the list. The two tetrads concerned are TM4657 and TM4658 and the walk starts, leaving Aldeburgh, a few hundred yards past the parish church, on the right. If you reach the Leiston road you have gone too fur. Initially it is shady with probably just Speckled Wood present but once you clear this short stretch you are on a permissive footpath following the path of the old railway line. The back of a caravan site is on your right and wider views across to RSPB North Warren on your left. The masses of bramble bushes attract most of the species, and these include three skippers and three whites, Red Admiral, Peacock, Comma, Small

Table 1. 2005 Weather for East Anglia Season Winter 04/05 Spring Summer Autumn

Mean Temp Deg C 5.6 9.4 16.5 12

Anomaly % up 1.2 1.2 0.9 1.5

Sunshine hrs 193.9 435.0 552.4 386.8

Source: www.meroffice.gov.uk/ climate/ uk Anomalies are measured against the 1961 to 1990 averages.

Anomaly % 115 98 97 121

Rainfall mm 98.9 109.4 152.4 170.9

Anomaly % 69 79 98 105

Holly Blue

Common Blue

by Mervyn Crawford

by DouglasHammersley 15

Summer2006

The Suffolk Argus Suffolk Butterflies", and this already merits an update. Milder winters and earlier springs have brought many species out earlier, and 10 Suffolk firsts have been bettered in the six and a half seasons since the Millennium Atlas was compiled. One of these, the Small Copper is the only early record for 2006 - up to the time of writing, (May 1st) - unless you know better! The table has been drawn up to highlight the recent changes, and to credit the observers. Another 6 late records were beaten, with extended summers allowing Browns to fly later and the White Admiral managing a second brood in 2004. As climate change continues, we may expect further additions before long.

Early and Late Records Update by Rob Parker Richard Stewart published a table of the earliest and latest Suffolk sightings for each species on pages 36 to 38 of "The Millennium Atlas of

Early/Late Records

previously unknown sites. Over the period since 1995, records have now been made from 84 tetrads, although not all of these represent established colonies, and the steady increase is a measure of recording effort rather than a genuine spread of the species. Separate detailed accounts for each of the BAP species are available as annexes [Not attached].

Spring brought only one earlier than ever record a Brown Argus on April 28th. Autumn was mild, sunny and extended, with the Browns flying later than usual - on October 6th, both Meadow Brown and Gatekeeper were still on the wing. This is later than previous records by just a day for Meadow Brown, but by 10 days for Gatekeeper. Speckled Woods, Large Whites, Commas and Peacocks were all to be seen in sunny spells, but it was Red Admirals that were most noticed, with 33 records in November/December.

Migrants It was a poor year for migrants, with Painted Lady appearing in very low numbers. There were only 16 Clouded Yellow sightings, and no Camberwell Beauties or Queen of Spain Fritillaries.

Geographic Coverage Records were received from 493 tetrads, which is better than 2002 and 2003, but does not match last year's high of 530. In all, some 295 recorders contributed, and "regulars" were joined by new faces, some from SNS, others through BC's Spring Survey, and a good number through participation in the BTO's Garden Bird Watch, which encouraged butterflies to be noted alongside birds. Our distribution maps are improving as an increased number of observers record butterfly numbers, rather than simply presence.

Swallowtails Recorder

Earliest Earliest to 2005/6 to 2000

MarkComish ColinJacobs RobMacklin Merwn Crawford

20/06/03 27/03/06 06/06/03 28/03/05

RichardChamoion

16/06/03

RobParker RichardChamoion MikeTa~lor

28/03/02 19/04/02 21/06/03

DarrenUnderwood 25/05/04 J. Goslina 08/06/04

07/06/95 29/05/83 31/05/97 25/04/90 28/05/97 27/04/97 09/01/98 18/03/95 25/02/00 11/03/00 23/03/90 12/04/95 22/06/99 04/07/99 29/03/98 17/06/00 03/05/97 24/04/92 18/03/90 22/06/99 01/01/00 20/02/90 01/01/00 15/03/97 01/01/00 15/01/95 31/03/90 24/04/90 02/07/00 13/06/92 27/05/95 14/06/97 05/05/83

Species

Latest to2000

SmallSkinru,r EssexSkiooer Lan:ieSkipper DinaySkiooer Swallowtail CloudedYellow Brimstone LarqeWhite SmallWhite Green-veined White OranqeTio GreenHairstreak PurnleHairstreak White-letterH'streak SmallCoooer Silver-studdedBlue BrownAraus CommonBlue Holly Blue WhiteAdmiral RedAdmiral PaintedLady SmallTortoiseshell CamberwellBeautv Peacock Comma SoeckledWood Wall Gravlinq Gatekeeper MeadowBrown Rinalet Small Heath

25/09/95 12/09/84 31/08/84 04/07/83 28/08/91 21/11/32 15/11/95 01/11/59 27/10/94 29/10/95 20/07/95 20/07/96 08/09/00 28/08/00 16/11/84 21/08/83 23/10/99 06/11/94 01/11/84 01/09/51 11/12/94 20/11/95 28/12/97 14/10/96 31/12/97 12/12/00 03/11/95 30/10/95 22/09/95 21/09/95 16/09/84 27/08/84 04/10/99

Latest to 2005

Recorder

18/09/04

Merwn Crawford

Two adult Swallowtails were seen, one at Trimley and the other on the outskirts of Ipswich. There was no recurrence of the flurry of sightings made in 2004, and no reports oflarvae.

Residents 16/11/03

Merwn Crawford

11/10/04 25/12/02

NiqelCumminq MikeDean

Orange-tips, Holly Blues and Green Hairstreaks all did well in spring, although Holly Blues were not so numerous in the second brood. By summer, the shorrage of Small Tortoiseshells, Peacocks and Commas was a topic of general awa~eness,and it is possible that they are suffering from the spread of the parasitic Tachinid fly Sturmia be/la. Again, there was a very poor showing of the Wall, although the Grayling and Small Heath did not deteriorate below their low 2004 numbers. The White Admiral had a strong year, with sightings in 31 terrads, including 6 in totally new sites, following a year that produced a partial second brood. :rhe Small Tortoiseshell, noted in 66% of tetrads visited, remains our most widely reported butterfly, though it was closely challenged by the Speckled Wood and Green-veined White.

Purple Emperor.

06/10/05 06/10/05

LydiaCalYesbert LydiaCalvesbert

The surprising discovery of Purple Emperors flying in Theberton Woods was found to be the result of clandestine releases dating from 2000. It remains to be seen whether they can establish a sustainable breeding population in the wild.

SpeckledWood by Beryl]ohmon

The Suffolk Argus

Summer2006

Species Maps

Bemer's Heath [TL7977J. The northern edge of Berner's Heath has plenty of Bird's-foot Trefoil along the rather exposed northern edge. It was visited twice (May 16th in poor weather & Jun 17th in good conditions) without success.

Annual Report on Silver-

Distribution Maps for individual species have been prepared for our 31 regulars, and these are available for reference as required. This year's total species count stands at 33 if the introduced Purple Emperor is included.

Analysis Relative scarcity can be deduced from a count of the number of tetrads from which each species has been recorded. Our rarest native butterflies are usually the 3 BAP species, followed by the White Admiral. This year's league table reflects a numb~r of changes, with Clouded Yellow appearing high up as a result of the poor migration season. Encouragingly, White Admiral and Holly Blue are much improved, but worryingly, the Wall was only found in 6% of the squares surveyed. Year-on-year change is not simple to quantify: a straight tetrad count is less meaningful than the percentage of survey squares in which each species was found. Neither measure assesses a butterfly's abundance at its breeding sire as accurately as the "index" derived from transect walks.

studded Blue for 2005 by Rob Parker Season 2005 started late by comparison with the past 2 s.easons. A cool, wet spring protracted larval feeding, and the butterfly was not on the wing until June 18th, compared with June 7th in 2003/4. A summer interrupted by heavy rain spoiled survey effort as well as depressing the peak figures at most colonies. Relatively low temperatures reduced the prospects for colonising activity late in the summer.

Transects Derailed data was submitted for the established transects at North Warren (Rob Macklin), Fynn Valley (Richard Stewart), RSPB Minsmere (Robin Harvey), Bradfield Woods (Steve Hunt), Center Pares (Graham Hersey-Green), Cavenham Heath (Michael Taylor), Walberswick (Adam Burrows) and Bury Sr Edmunds (Rob Parker). Four new transects have also produced results this season: Wolves Wood (Mark Nowers), Newsons Farm (Frances Bee), Barham picnic site (Nick Dickson) and Upper Abbey Farm (Trudy Seagon), bringing the roral to 12 full transects and 3 single-species transects. Special thanks are due to all those transect walkers for their regular monitoring, which provides an objective abundance count as well as site-specific observations, and flight times.

The Counts The main count at Minsmere had been planned for June 20th, and a team of volunteers counted the two main colony areas until it became clear that the population was predominantly male, and well short of its peak. Unfortunately the re-count two weeks later was hit by torrential rain, and the third attempt was past the peak, so the results were unsatisfactory. Most other colonies were adequately counted, although recorders had to make several visits to get reasonable results. An initiative to inuoduce mini transects at Minsmere got off to a poor start, but was trialled sufficiently to devise a workable plan for future years.

Annexes [to be published later]: Scarcity 2004 & 2005 Analysis of 11 Years to 2005 Derailed reports for BAP species. Silver-studded Blue Dingy Skipper and White-letter Hairstreak

Sketchfar [TL836801J. See remarks above, under Marmansgrave Wood. Shepherd's Grove [TL987l}. This area has some Bird's-foot Trefoil on the former airfield, not far from the planned IKEA development. It was surveyed on Jun 8th, but did not appear suitable for Dingy Skipper.

DingySkipper by DouglasHammersley

Haverhill Industrial [TL6844). This area (mainly just outside VC26) has Bird'sfoot Trefoil, and had been suggested as a postindustrial site worth inspection. Three visits were made, but no Dingy Skipper were found.

Euston Quarry [TL896775}. This wonderful CWS has everything that ought to make a good Dingy Skipper site, including Bird'sfoot Trefoil and a Common Blue colony. It was inspected early this year, on May 8th, but for the third year in succession, no Dingy Skippers were found.

Rob Parker,County Butterfly Recorder. July, 2005

OTHER SITES (Inspected, with negative results)

LANDOWNERS (and other interested parties, for reference)

Cut-off Channel [TL7386]. , During Norfolk's 2004 survey for Grizzled ancf Dingy Skipper, both were found along the watercourse known as the Cut-off Channel, which has a chalky double embankment along a nine mile stretch in Norfolk. Visits to the Suffolk stretch were made on May 12th (after finding DS flying \n nearby Norfolk), but there was a shortage of Bird's-foot Trefoil, and nothing was seen.

Euston Estate (Chris Spicer) Elveden Estate Qim Rudderham) Thetford IP24 3TQ Stamper Farms O.Stamper, West Farm) IP24 North Farm (Rob Watson) IP24 East Farm (David Heading) Barnham IP24 2QN Forest Enterprise (Nick Gibbons) RAF Hanington (Gwyn Smith) Center Pares (Ecology Manager) Brecks Countryside Project Norfolk Butterfly Recorder (Patrick Bonham) BC EoE Regional Officer, Butterfly Conservation (Sharon Heade) East of England Tank Museum (Sean Hindle) Barnham IP24 Environment Agency Suffolk Biodiversity Partnership

Thetford Rifle Range [TL8480J. This MoD site lies in administrative Norfolk, bur is in Suffolk's biological recording area. It has plenty of Bird's-foot Trefoil in a suitably sheltered area, and was walked extensively on May 24th in poor weather and again on May 25th in hot weather. Although the habirat looked excellent, it was disappointing not to find any Dingy Skippers.

The Suffolk Argus

Summer2006

ACTIVE COWNIES

Elveden (Center Pares) [TL810805). A site visit with Center Pares Ecology Manager found at lease 9 Dingy Skipper flying on May 18th, and staff revisiting on May 27th were able to find 15. The area mown as the bird walk will be managed with the Bird's-foot Trefoil in mind.

RAF Barnham [TL 8580/8680}. The first visit to the Barnham Training Area, in fair weather found not a single Dingy Skipper, even though they were flying elsewhere on that day. This is alarming, at what ought to be our strongest colony. Sheep now graze the trainjng area, and 64 were in the Dingy Skipper area on that day. By arrangement, English Nature attended the next visit on Jun 3rd to assess the impact of grazing on the sward. On that day, just one Dingy Skipper flew, and the flowering of the Bird's-foot Trefoil was late.

DEFUNCT SITES King's Forest Oohn O'Groats Cottages) [TL818737}. One Dingy Skipper was found on the track from the main road towards John O'Groats Cottages, and this was the first sighting on the west of the BI 106 since the Millennium survey. However, there is not much suitable habitat in this area, and the significance of one stray crossing the road should not be overstated (this point is only 200m from the edge of the Archery colony}.

King's Forest {Wordwell) [TL 834732}. This site recorded a maJOmum count of 16 on May 27th, and again the Dingy Skippers were flying further to the south and west than the main ride, extenrung their domain to include the sheltered glades to the west of the tree line.

Marmansgrave Wood [TL8480}. An abundance of Common Blues in this area suggest that Bird's-foot Trefoil may exist along the footpath, but the bracken encroachment continues, and the former site may be considered defunct. A sheep-grazed area in the Elveden Estate's Sketchfar domain has one promising looking corner at TL836801, which deserves a visit next year.

The count of 377 includes one well-populated flight area where the heather is re-growing following an accidental burn, so the reality of a low count in other areas is somewhat concealed. The area in need of cutting is enormous and beyond the resources of the Martlesham Conservation Group. If English Nature funds can be released to enable forage harvesting in the (privately owned) airfield area, the colony will have a future, otherwise the prospects are not good.

Wenhaston Black Heath For the third year in succession, the population has been barely detectable, and Silver-studded Blue have been noted only in the traditional ilight area, even though other areas of pioneer heather are now available nearby. Habitat work by the Wenhascon volunteer group continues.

Visits by 3 separate recorders found no more than 6 Silver-studded Blue, and none were found on the' adjacent Golf Course. This is a serious crash from the recent past: 2004:63, 2003:86, 2002: l 08, and 2001:145. In his 2003 report to Suffolk Wildlife Trust, Neil Ravenscroft warned that the over-mature condition of the heather, the low proportion of Erica, and the absence of ant colonies all presented grounds for concern. It is salutary that just 2 seasons after this alarm, the colony is in crisis. A number of discussions and an on-site meeting were held to assess the strength of the ant colonies and to consider appropriate heather management plans for the forthcoming winter. le was felt that past forage harvesting had been the correct technique, but that an insufficient area of pioneer heather had been created. To enlarge the area suitable for egg laying in 2006, forage harvesting will be undertaken to extend the width of each tract of cut heather. Adrucionally, a fresh tract will be cut to the south side of the footpath through the "main flight area".

Barnhamcross Common [TL86481 l]. This site lies adjacent to RAF Barnham, and occasional strays are seen on the south edge of Barnhamcross Common, which lies in administrative Norfolk, but in Suffolk's biological recording area. Several visits were made to the southern margin and the wider area of the common, but no Dingy Skippers were found.

King's Forest (Chalk Lane) [TL827752]. Numerous visits to this tradjtional site proved negative, although at least 2 were seen dose to the heathland regeneration area on May 25th. The tree felling discussed last year with the Forestry Commission has not yet come to pass. The 2004 records of strays further east and north were not reproduced, despite several independent searches.

Martlesham Heath

Purdis Heath

Kings Forest South [TL7872/8073/8272SW}. Not specifically targeted this year, but no casual records received.

King's Forest (Archery) [TL831737]. Only 300m north of the Wordwell site, but cut off by a forest compartment, lies an east-west track with good Bird's-foot Trefoil along the margins. This links to an area used for archery practice, part of which is kept mown. This year's count coincided with good weather and fresh emergences, and a team of 6 counted no less than 107 Dingy Skippers active on May 14th. On subsequent visits, the flight area was found to extend even further east and west than the first survey, its northern limit being the mature coniferous edge at TL830739. The Bird's-foot Trefoil grows over a wide area, and appears to flourish under the mowing regime implemented for the archers.

Results The results for the season's counts are tabulated below, and are generally .Jesscomplete than usual. Although the results for Minsmere, Walberswick, Westleton Heath and Common, Upper and Lower Hollesley are not high, they do not give cause for concern. Furthermore, there is some encouragement from the recently established colonies at Parsnip Plantation and Rushmere Heath, both of which have shown a gentle increase in numbers. Furthermore, overall distribution maps for 2005 show records from 17 tetrads, which is the second highest count since 1995. On the other hand, there was a population crash at Purdis Heath, and just one butterfly at Wenhaston Blackheath. Although the numbers at Mardesham Heath are higher (377) the downward trend does give cause for concern. These 3 sites need heather management, and are dealt with inruvidually below.

I --

\_"\_ ·•.

Silver-studded Blue by BerylJohnson

Summer2006

The Suffolk Argus Monitored Silver-studded

Blue sites listed geographically

Location

North GridReference Date 74 TM4074 BlackheathWenhaston TM420749 Jui TM4874 WalberswickComm'NNR TM491752 29-Jun 72 TM4472 70 TM4670 AldrinQhamWalks TM464612 1-Jul 68 TM4468 WestletonHeathNNR TM4569 29-Jun WestletonCommon TM44306870 3-Jul WestletonFootballPitch TM44406880 3-Jul MinsmereWestletonWalks TM459689 MinsmereSawmills TM452692 MinsmereFootballPitch TM451691 MinsmereNatteriackPond TM451693 MinsmereSW Como' 1 TM450694 MinsmerePit Como'2 TM457692 MinsmereSEComo'3 TM457691 MinsmereComo'20 N TM446683 MinsmereS Como'3 TM456693 MinsmereCentralComo' 3 TM453693 TM4668 MinsmerePowerlines TM461683 MinsmereNorth Bridlewav TM468687 MinsmerePotbrioos TM468689 20-Jun MinsmereNorth Grimstones TM462688 20-Jun MinsmereE Como' 13 TM468681 MinsmereComo' 13 track TM464681 MinsmereComo' 13 Tanktrao TM466683 DunwichHeath TM468687 1&03 Jui 66 TM4466 Como'20 South TM445670 GravelPit TM449669 46 TM3246 UpperHolleslevMoD TM33344723 11-Jul TM3446 "Lower Holleslev""A""" TM342465 2-Jul "Lower Holleslev""8""" TM343461 2-Jul "Lower Holleslev""C""" TM350460 28-Jun 44 TM2044 RushmereHeath TM202448 14-Jul TM2244 MartleshamHeath TM2445 10-Jul TM3244 ParsnioPlantation TM32724579 11-Jul 42 TM2042 "Ipswich Golf Club,Purdis" TM208432 Jui PurdisHeath TM21204270 6-Jul 40 TM2040 IndustrialEstate TM207419 6-Jul

from the North

Observer

RichardHavard Adam Burrows

Male

Female Total

Rob Macklin

179

217

Adam Burrows DavidRous DavidRous

137 175 25

39 77 15

176 252 40 0 0 0

0 0 0 0 0 0 0

Mel Kemo Mel Kemo

DavidSutton

47 368

0 37

0 0 47 405 0 0 0 2 0 0

DavidMason

159

192

RichardStewart RichardStewart DavidMason

325 244 22

142 91 2

467 335 24

not split

377

0 6

0 0

0 6

RichardStewart 47 1787 2005 Totals

20 508

67 2672

DavidMason Phil Smith DavidMason Neil Sherman RichardStewart

appears to be holding its own in a very limited area of the Suffolk Brecks, covered by just 5 tetrads.

Dingy Skipper Survey, 2005

2005 SURVEY The Dingy Skipper was on the wing from late April elsewhere in UK, and on the Devil's Dyke (Cambs/Suffolk border) by May 2nd, but the Brecks population was again later. None were flying on May 6th, and the first definite record was from Wardwell on May 14th. The cool wet spell at the start of May had the effect of extending the flight period. This finished at Devil's Dyke by June 8th {last sighting May 28th), yet they were still present in King's Forest on June 18th. The survey involved 19 participants, and the main events were:

by Rob Parker SUMMARY

The 2005 survey continued the intensive study of 2004, refining our knowledge of the extent of the Dingy Skipper's distribution. The newly found colony in the Archery area of King's Forest was found to be flourishing, with a peak count of 115, and an expanded-flight area. On the other hand, the established colony at RAF Apr 29th - Training at Barnham (Spring Survey Barnham had a very poor showing, with just one Event). Dingy Skipper seen in rwo separate visits. This abrupt change is probably related to the recently introduced sheep grazing regime, and needs . May 12th - Survey along Cut-off Channel in Lakenheath area. careful management, if the colony is to survive. Continued checks of former sites did not reveal any unexpected records, and there were only· May 14th - Counts at Wardwell & Archery area, but nothing found at Chalk Lane or to the north a few sightings in the Chalk Lane areas. east. A number of possible sites in peripheral areas were investigated this year, notably along the CutMay 18th - Count at Center Pares, repeated by off Channel, where no Dingy Skippers were staff on Ma!J27th. found, although the banks of the same waterway do hold good populations just a few miles into· May 23rd - RAF Barnham survey - negative, Norfolk. Tlie population on the Devil's Dyke repeated Jun 3rd - only one seen. remains strong, although this lies just outside VC26, i.e. in Cambridgeshire's recording area. May 24-25th - Surveys at Thetford rifle range The very promising site at the Thetford Rifle Range was inspected, but no Dingy Skippers were May 25th - Chalk Lane; 2 seen. found despite the apparently suitable habitat. The season was again later in the Brecks than May 30th - King's Forest; one seen west of road in Cambs, and this was exaggerated by the cold (first since Millennium survey). wet spell in early May. The flight period became rather extended, and some Dingy Skippers were May 6-30th - Negative searches made at Euston, still flying in King's Forest on June 18th. Sketchfar, Marmansgrave, Barnhamcross, Berners All visits were conducted with the Heath, also Shepherd's Grove and Haverhill etc. landowner's consent, or along public rights of way. A grant from Awards for All enabled volunteers to A total of 17 sites were visited during the 2005 be reimbursed for mileage undertaken during the flight period. Dingy Skippers were found only at survey. The sites visited are listed individually the established sites, including an isolated, but below, as active, defunct or for future investigation. stable colony at Center Pares. The butterfly

Summer2006

The Suffolk Argus Monitored Silver-studded

Blue sites listed geographically

Location

from the North

Observer

RichardHavard Adam Burrows

Male

Female Total

Rob Macklin

179

217

Adam Burrows DavidRous DavidRous

137 175 25

39 77 15

176 252 40 0 0 0

0 0 0 0 0 0 0

Mel Kemo Mel Kemo

DavidSutton

47 368

0 37

0 0 47 405 0 0 0 2 0 0

DavidMason

159

192

RichardStewart RichardStewart DavidMason

325 244 22

142 91 2

467 335 24

not split

377

0 6

0 0

0 6

RichardStewart 47 1787 2005 Totals

20 508

67 2672

DavidMason Phil Smith DavidMason Neil Sherman RichardStewart

appears to be holding its own in a very limited area of the Suffolk Brecks, covered by just 5 tetrads.

Dingy Skipper Survey, 2005

by Rob Parker SUMMARY

The Suffolk Argus

Summer2006

ACTIVE COWNIES

Martlesham Heath

Purdis Heath

Kings Forest South [TL7872/8073/8272SW}. Not specifically targeted this year, but no casual records received.

I --

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Silver-studded Blue by BerylJohnson

The Suffolk Argus

Summer2006

Species Maps

Annual Report on Silver-

Annexes [to be published later]: Scarcity 2004 & 2005 Analysis of 11 Years to 2005 Derailed reports for BAP species. Silver-studded Blue Dingy Skipper and White-letter Hairstreak

DingySkipper by DouglasHammersley

Rob Parker,County Butterfly Recorder. July, 2005

OTHER SITES (Inspected, with negative results)

LANDOWNERS (and other interested parties, for reference)

Summer2006

Early and Late Records Update by Rob Parker Richard Stewart published a table of the earliest and latest Suffolk sightings for each species on pages 36 to 38 of "The Millennium Atlas of

Early/Late Records

Migrants It was a poor year for migrants, with Painted Lady appearing in very low numbers. There were only 16 Clouded Yellow sightings, and no Camberwell Beauties or Queen of Spain Fritillaries.

Swallowtails Recorder

Earliest Earliest to 2005/6 to 2000

MarkComish ColinJacobs RobMacklin Merwn Crawford

20/06/03 27/03/06 06/06/03 28/03/05

RichardChamoion

16/06/03

RobParker RichardChamoion MikeTa~lor

28/03/02 19/04/02 21/06/03

DarrenUnderwood 25/05/04 J. Goslina 08/06/04

Species

Latest to2000

Latest to 2005

Recorder

18/09/04

Merwn Crawford

Two adult Swallowtails were seen, one at Trimley and the other on the outskirts of Ipswich. There was no recurrence of the flurry of sightings made in 2004, and no reports oflarvae.

Residents 16/11/03

Merwn Crawford

11/10/04 25/12/02

NiqelCumminq MikeDean

Purple Emperor.

06/10/05 06/10/05

LydiaCalYesbert LydiaCalvesbert

SpeckledWood by Beryl]ohmon

The Suffolk Argus

2005 Butterfly Report

Hot Spots for

Table 1. 2005 Weather for East Anglia Season Winter 04/05 Spring Summer Autumn

Mean Temp Deg C 5.6 9.4 16.5 12

Anomaly % up 1.2 1.2 0.9 1.5

Sunshine hrs 193.9 435.0 552.4 386.8

Source: www.meroffice.gov.uk/ climate/ uk Anomalies are measured against the 1961 to 1990 averages.

Anomaly % 115 98 97 121

Rainfall mm 98.9 109.4 152.4 170.9

Anomaly % 69 79 98 105

Holly Blue

Common Blue

by Mervyn Crawford

by DouglasHammersley 15

Summer2006

The Suffolk Argus

Grayling by Douglas Hammersley

My Net

Grayling records 2000 to 2004 inclusive.

Note the polarisationtowardsthe sandy areasof the Brecksand the Sandlings. Found in a total of I 08 tetradsover thefive yearperiod.

Written Autumn 2005

Key: • 1 sighting • 2-9 max seen • 10+ max seen

Summer2006

Graylings • in

Suffolk

When did you last see a Wall Brown or a Small Heath?

,...-:'"

by DouglasHammersley

The Suffolk Argus

Summer2006

Save our Butterflies Week 22-30 July

Open Garden for Butterflies & Moths Sat 29th July At "PriorsOak" Leiston Rd, Aldeburgh 10:30 to 12:30

Editorial by Stuart Gough

Programme Amendment

Priors Oak lies one mile north of Aldeburgh on the B 1122, on the left.

www.suffolkbutterflies.org.uk 18

Summer2006

The Suffolk Argus

Contents

§Jat,~f;~ps

Editorial

3 4 6 8 11 14 15 16 17 18 19 Back Cover

For that difficult to find present, why not give a decorative butterfly or moth lo mount on the front wall of someone's home ?

Copy Dates Contributions for our newsletter should reach the Editor {address on back page) no later than:

Spring

Christmas Eve

Summer

April Fools Day

Autumn

Any piece of writing that is considered to be of interest will be published together with line drawings/prints /photographs. The Suffolk Argus is your magazine, so please let us hear from you.

To advertise in the Suffolk Argus please contact Mike Dean on 01359 230292.

111·~-~l ··· r14¼·,. :1'~---~l--..,-_ -~·tl/J1fitJp··.--~ ~ ..p,,i.._;,.------

SUFFOL

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•, '----~1. ..• . )i ;

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MOTHGROU

Phone or fax Mervyn Crawford on Mildenhall (01638) 712600 for Colour brochure I Price list

Pric'e list

Suffolk Branch Contacts President

Howard Mendel, do The Natural History Museum, Cromwell Road, London, SW7 5BD (0171 938 8782) Chairman

Mike Dean, Coach House, lxworth, Bury St. Edmunds, Suffolk IP3 l 2HL (01359 230292)

The Butterfly Conservation Conservation Officer (Butterflies}

Rob Parker, 66 Cornfield Road, Bury St. Edmunds, Suffolk IP33 3BN (01284 705476) Conservation Officer (Moths)

Tony Prichard, 3 Powling Road, Ipswich, Suffolk, IP3 9JR {01473 270047) County Recorder (Moths)

Membership Secretary

Tony Prichard (address above}

Beryl Johnson, 28 Medway Road, Ipswich, Suffolk IP3 0QH (01473 715701)

Tony Prichard, (address above)

Newsletter Editor

(Vacant} Publicity Officer (Vacant) Programme Secretary

Alan Johnson, 28 Medway Road, Ipswich, Suffolk IP3 0QH (01473 715701) County Recorder (Butterflies)

Secretary

Treasurer

Jim Foster, Lugano, The Street, Stonham Aspal, Stowmarket, Suffolk IP14 6AH (01449711484) Regional Officer Eastern Region

Sharon Hearle, do Busy Bee, 21 High St., Newmarket, Suffolk CBS 8LX (0 1638 731648) sharon@butterfly-conservation.org

Rob Parker (address above right) Committee Members

Stella Wolfe,

Volunteers Needed

ekeeper by BerylJohnson

If you feel you could help out now and then with the growing work of the Branch, please contact Beryl Johnson on 01473 715701.

/',

/ /

,,;!;~

The Newsletter of the Suffolk Branch of Butterfly Conservation

Butterfly Conservation

Summer 2006 Volume38

Suffolk Argus 38 Summer 2006

Articles inside

Newsletter Details and General Information Suffolk Branch Contacts Back Cover

Graylings in Suffolk

Early and Late Records Update

My Net Reaction

Dingy Skipper Survey 2005

Hot Spots for Butterflies

Editorial

Annual Report on Silver-studded Blue 2005

2005 Butterfly Report