Observations on the Swallowtail Butterfly, Papilio machaon L in Suffolk 1998.

98

Suffolk Natural History,

Vol. 35

OBSERVATIONS ON THE SWALLOWTAIL BUTTERFLY, PAPILIO MACHAON L. IN S U F F O L K 1998.

R. G. STEWART In 1998 I received eleven rccords of thc Swallowtail butterfly in Suffolk. This is an cxceptional number, compared to just six during thc three previous years of the current Millennium survey. The problems of authenticity are complex and none of thosc reported in 1998 presented any opportumty for close examination. In addition 'records are bedevilled by introduetions and fraud' (Thomas & Lewingion, 1991) while, referring speeifieally to Suffolk, Mendel and Piotrowski (1986) add that 'The Situation in Suffolk is further confused by the considerable number of attempted introduetions and deliberate releases'.

During the course of the current Millennium Survey at least two sources of breeding and releasing of butterflies have been identified, both mvolving Swallowtails, one close to the border at Diss and the other at Wenhaston. In fact, the only Swallowtail record I have had to reject outright was in a village garden at Wenhaston.

The Situation is further compounded by the climatic changes. Over htty years ago it was stated that 'Specimens of Swallowtails found at times in different parts of Southern England and in Kent in particular, have proved, on examination, to bc immigrants from France. These immigrants sometimes breed in this country but are not able to establish themselves permanently' (Beaufoy, 1947). Thomas and Lewington (1991) suggest 'There is also the chance if our climate does indeed become warmer, that the continental species P. m. gorganus, will establish itself in the South. It is a far commoner immigrant than is generally thought'.

The British Swallowtail, subspecies britannicus Seitz, is to be found in well-established colonies along the valley of the river Yare below Norwich.

The RSPB Reserve at Strumpshaw has a strong colony and my own recording there indicates a particularly successful second brood still on the wing well into September (Stewart, 1993). Although this sub-species is not migratory 'it is still a powerful flier that wanders between all the Broads adjoining the nvers Ant, Thurnc and Bure' (Thomas & Lewington, 1991). This capacity would make the presence of this native sub-species in the Beccles area of the Waveney Valley a distinet possibility - on a clear day the tall chimney of the sugar beet factory at Cantley, not far from Strumpshaw, can be seen. This part of Suffolk also from my own recording experiences, has several sites with tall, vigorous growth of milk parsley, Peucedanum palustre, which is almost exclusively the food plant of subsp. britannicus.

There were, however, no 1998 reports from this part of Suffolk. All eleven records occurred between 2Ist of July and 12th August. These dates strongly suggest P. m. gorganus and two records came from coastal sites: Minsmere on 5th August (Don Dorling) TM472672 and near Thorpencss on 1 Ith August (Rob Macklin) TM463596. The third was close to thc river Deben at Woodbridge on 25th July (Anne and Sam Beaufoy) TM273487. This record is further inland but on a tidal river. These three have been aeeepted as genuine migrants.

Trans. Suffolk Nat. Soc. 35

(1999)

SWALLOWTAILS IN 1998

99

The other cight present a morc complex Situation. They also cover the same twenty-three day timc span. Rccorded sighlings were from R u s h m e r c Road (Neil Sherman) T M 191456, Bixley Road (Wilf W e b b e r ) T M 194433 H u m b e r Doucy Lane (Barry Gooding) T M 196458 and a fortuitous glimpse from a w i n d o w of the Civic Drive in I p s w i c h ( S i m o n Kellett) T M 159477. T h e remaining four all came f r o m a small area in or close to the Rivers Estatc in Ipswich, namely two at Trent Road (Colin Gilbert, R o s e m a r y Carr) both T M 178428, one at M e d w a y Road (Alan and Beiyl J o h n s o n ) T M 179428 and one at Powling Road (Vivienne W o o d s ) T M 184427. T h e s e four covered the w h o l e ot the twenty-three day time span.

Their proximity to the tidal river Orwell gives s o m e credibility to their claim as genuine migrants though I reeeived no reports of Swallowtails in 1998 f r o m anywhere between Ipswich and the coast. There were also no records f r o m nearby Essex (Dr. Val Perrin, pers. comm.). There is also the possibility that all eight sightings were of just one individual. Perhaps the most vital Information, reeeived only recently, was of 'three or f o u r ' seen on subsequent days on the Rivers Estate but this information could not be substantiated by any w n t t e n records or definite dates, so it will have to be discounted.

Various c o m m e n t s about origin and sub-species were included on the Rare Butterfly f o r m s completed but these two sub-species are particularly difficult to differentiate: 'Even preserved speeimens can be difficult to assign, as d i s t i n g u i s h i n g characters o v e r l a p ' ( M e n d e l & P i o t r o w s k i , 1986). T h e proximity of all the Ipswich sightings would suggest a possible release but unless anyone admits to this their derivation must remain a matter of doubt T h e only definite conclusion is the difficulty of authenticity faced by any analysis of Swallowtail records outside their breeding colonies.

There is a sequel - I subsequently reeeived reports of two Swallowtail caterpillars, the first f r o m Westerfield R o a d in Ipswich ( T M 167457). This was identified and photographed on 28th September as it fed on garden rue Ruia graveolens (see Plate 10). This is identified as one of the plants often used by subsp. gorganus caterpillars ( M a i t l a n d - E m m e t t and H e a t h , 1990) U n f o r t u n a t e l y it succumbed to a spell of bad weather shortly afterwards. T h e second, in a garden along the Felixstowe Road at Nacton ( T M 2 1 8 4 1 4 ) was first identified in late August, feeding on Choisya. T h i s is a m e m b e r of the citrus f a m i l y and 'Citrus is regarded as the ancestral f o o d p l a n t of all S w a l l o w t a i l s ' (David Carter, Collections M a n a g e r , L e p i d o p t e r a , Natural History M u s e u m , London, pers. comm.). These records reinforce the gorganus I d e n t i f i c a t i o n of the Ipswich sightings as the time i n v o l v e d would a c c o m m o d a t e egg-laying and emergence of the Caterpillar. T h e second pupated successfully but I was i n f o r m e d early in June 1999 that only an empty case r e m a i n e d and no emergence had been observed!

References B e a u f o y , S. (1947). Butterfly lives. London: Collins.

M a i t l a n d - E m m e t , A. & Heath, J. ( \ 9 W ) . T h e moths and butterflies Britain and Ireland 7(1). Colchester: Harley Books.

M e n d e l , H. & Piotrowski, S. H. (1986). The butterflies of Suffolk.

S u f f o l k Naturalists' Society.

Trans. Suffolk

of

Nat. Soc. 35

Great

Ipswich-

(1999)

100

Suffolk Natural History, Vol. 35

Stewart, R. G. (1993). Swallowtails at Strumpshaw. White Admiral 25: 5-7.

Thomas, J. & Lewington, R. (1991). The butterflies of Britain and Ireland.

London: Dorling Kindersley.

Richard Stewart (County Butterfly Recorder) Valezina 112,Westcrfield Road Ipswich IP4 2XW Notes on some bryophytes recorded in Suffolk during 1998 I suppose it is inevitable that when studying an 'unpopulär' group like bryophytes, new and interesting records should turn up regularly. Although new county records are always exciting it is perhaps more satisfying when species only seen once, turn up in other areas. Platygyrium repens, Cinclidotus mucronatus and Orthotrichum tenellum were each found for the second time, the latter again by David Strauss who also found Platygyrium repens near Thorpness, new to VC25. One of the most exciting discoveries was of the moss Leptodontium gemmascens, on decaying leaves and stems, amongst grasses on the 'denes' just North of Dunwich, the third record of this very rare plant from the county. New to the county list was Phascum floerkeanum from an arablc field at Raydon. This is a minute species, perhaps a millimetre tall and wide and is undoubtedly much overlooked. In December two remarkable discoveries were made. The first was during a meeting organised by the Cambridge Group to Mildenhall Woods when Dr R. A. Finch found the liverwort Lophocolea semiteres. This is a New Zealand species which in Britain had previously, only been known from the Scilly isles and an arboretum in Scotland. It is well established in Europe on the Dutch/Belgian border. Upon seeing it, Robin Stevenson realised that it was a plant he has found near King's Lynn that has puzzled him for some time, and I also realised that an odd plant that I had collected near Sizewell a few years ago is also this species. David Strauss has since found it on Dunwich Heath so it would appear to be well established in East Anglia as well. Only two weeks after all this excitement another Southern hcmisphere plant, the moss Hennediella stanfordensis was found during a local meeting to a disused chalk pit in Offton. First found in Britain on the Lizard peninsula in 1958 this is only the second record from Eastcrn England.

Richard Fisk, 1 Paradise Row, Ringsfield, Beccles, Suffolk NR34 8LQ

Trans. Suffolk Nat. Soc. 35 (1999)

101 1998 notes on Microlepidoptera The following spccics werc obscrvcd at Framlingham during thc period 26th July lo 3rd August. The spccies numbcrs follow Bradlcy (1998) and thc vcrnacular names are taken from the samc sourcc or from Heslop (1947). Notes on larval foods are based on Emmet (1991). Although moslof these spccies arc common, it was thought worthwhile to record thcir occurrcnce, if only to compare with thc comments of Morley (1937).

385 Anthophila fabriciana August

Linn. (Fabricius's Nettle-tap) on ncttles, 27 July, 2

644 Borkhausenia fuscescens Hb. (Faint-dotted Tubic) on dccaycd leaves in birds' nests, 28, 30 July, 2 August 647 Hofmannophila pseudospretella materials, 29 July

Stt. (Brown

House-moth) on dry

6b8 Carcina guercana Fabr. (Oak Long-horned Flat-body) on various trecs and bushes, 26 July 688 Agonopterix heracliana umbels, 26 July 868 Helcystogramma July, 2 August

Linn. (Comon Flat-body) on leaves and flowers of

rufescens

Haw. (Wainscot Obscure) on grasses, 28, 30

870 Oegoconia quadripuncta Haw. (Four-spotted Obscure) on leaf litter, regarded as distinctly local by Morley, 26, 29, 31 July, 2 August 873 Blastobasis lignea Wals. (Furness Dowd) on vegetable matter, droppings, 31 July 937 Agapeta August

hamana

Linn. (Hook-marked Conch) on thistles, 29 July, 2

972 Pandemis heparana D. & S. (Dark Fruit-trce Tortrix), on various trees and shrubs, 26 July 994 Clepsis consimilana 31 July

Hb. (Saffron Twist) on privet, other bushes and trees

1016 Cnephasia longana Haw. (Long-winged Shadc) polyphagous on various herbaeeous plants, 2 August 1021 Cnephasia asseclana D.&S. (Flax Tortrix) polyphagous on various herbaeeous plants, 28, 29 July 1036 Acleris forsskaleana July

Linn. (Forsskal's Button) on maple, sycamore, 27

1048 Acleris variegana D.&S. (Gardcn-rose Tortrix) roses and other trecs and plants, 28, 29, 30 July 1201 Eucosma cana Haw. (Hoary Sealcd Bell) on thistles, knapweeds, 26 July, 2 August 1293 Chrysoteuchia culmella Linn. (Garden Grass-venecr) on grasses, 26 27 28, 29, 30, 31 July, 1, 3 August 1302 Crambus August

perlella

Scop. (Yellow Satin Grass-vencer) on grasses, 2

Trans. Suffolk Nat. Soc. 35

(1999)

102

Suffolk Natural History, Vol. 35

1303 Agriphila selasella Hb. (Pale-streaked Grass-veneer) on marshy grasses, a distinclly local spccies, 27 July 1304 Agriphila Straminella D.&S. (Straw-coloured Grass-veneer) on grasses, 26, 27, 28, 29 July, 2, 3 August 1305 Agriphila tristella D.&S. (Comon Grass-veneer) on grasses, 27, 31 July, 2 August 1316 Catoptria falsella D.&S. (Chequered Grass-veneer) on mosses, 29, 31 July, 2 August 1340 Eudonia truncicolella Stt. (Rustic Grey) on mosses, regarded by Morley as a distinctly local species, 31 July 1344 Eudonia mercurella Linn. (Small Grey) on mosses, 27, 28, 29, 30 July 1376 Eurrhypara hortulata Linn. (Small Magpie) on nettles, mint, 26, 27, 30 July 1388 Udea lutealis Hb. (Pale Straw Pearl) on herbaceous plants, 26 July, 2, 3 August 1390 Udea prunalis D.&S. (Dusky Brindled Pearl) on herbaceous plants, 28, 29 July 1421 Aglossa pinguinalis Linn. (Largc Tabby) on chaff, vegetable refuse, 27, 28 July 1424 Endotricha flammealis D.&S. (Rosy-flounced Tabby) polyphagous, 26 July 1426 Achroia grisella Fabr. (Lesser Wax Moth) on old combs in bee-hives, 26 July - three specimens 1428 Aphomia sociella Linn. (Bee Moth) on combs in nests of Hymenoptera, 26, 28 July References Bradley, J. D. (1998). Checklist of Lepidoptera recordedfrom the British Isles.

Fordingbridge, Hants: D. J. & M. J. Bradley.

Emmet, A. M. (1991). The moths and butterflies ofGreat Britain and Ireland.

Vol. 7(2). Colchester: Harley Books.

Heslop, I. R. P. (1947). Indexed check-list of the British Lepidoptera with the English Name of each of the 2313 Species. London: Watkins & Doncaster.

Morley, C. (1937). Final catalogue of the Lepidoptera of Suffolk. Ipswich: Suffolk Naturalists' Society.

Alasdair Aston Wake's Cottage, Seiborne, Hampshire GU34 3JH

Trans. Suffolk Nat. Soc. 35 (1999)

FRESHWATER INVERTEBRATE RECORDING

103

Freshwater Invertebrate Recording in Suffolk County Recorder's Annual Report Since my report on the Aquatic Heteroptera (TSNS 34, 1998) the number of records in the Freshwater Invertebrate Survey of Suffolk database has grown to nearly 30,000. Almost 800 records bcing added last year despite the constraints of fĂźll time teaching. At least another thousand records remain on paper and in notebooks, awaiting input onto Computer. Thirty four individual Orders of invertebrates and nearly 500 species are represented by individual records.

The recent series of dry summers and winters seems to have ended and last year the water levels in ponds and rivers were higher than for some time. This will hopefully be reflected in increases in the populations of certain invertebrates, which may have suffered as a result. A case in point is that of Cladocera or water fleas. Some lakes and ponds which I have sampled fairly regularly for the last few years have shown a marked decline in the number of species, and in some cases samples preserved from last summer still showed almost a monoculture of Simocephalus vetulus. It will be interesting to note whether improvements in water supply will be matched by changes in Cladoceran population dynamics.

I have been able to add many species records to the FISS database, although no new species were taken last year. However very few records were received from other recorders and I really do need more information from across the county to obtain a clearer picture of aquatic invertebrate status in Suffolk.

On a brighter note the FISS Website is now eighteen months old at the time of writing and has attracted about 8,000 visitors. Many of these are searching for information about pond and stream life and I have been busy answering questions from students both from Britain and around the world in places as far afield as America, Australia, the Middle East and even from islands in the Pacific. Unfortunately I have not had any Suffolk Records from this source.

The SNS publication White Admiral is also published via the FISS site and is slowly building up it's own internet readership.

One target for the year to come is to survey more ponds, as current data has predominantly been obtained from rivers. Naturalists who might not be able to supply invertebrate identifications can still help my survey by suggesting good quality ponds or lakes in the county, which can be sampled. This would help a great deal as the quality and even existence of ponds is not something that can be reliably deduced from maps.

Adrian Chalkley, 37 Brook Hall Road, Boxford, Sudbury, Suffolk C 0 1 0 5HS E-mail Adrian@fiss.puplenet.co.uk FISS Website http://www.fiss.purplenet.co.uk

Trans. Suffolk Nat. Soc. 35

(1999)

Plate 10: Swallowtail, Papilio machaon L., larva in Ipswich, 28th September 1998 feeding on garden rue, Ruta graveolens (p. 99).