NOTES AND COMMENTS ON SOME SUFFOLK MOTHS IN 1998 M. R. HALL A spell of unseasonally mild weather during early February raised hopes that perhaps 1998 would break the pattern of the last few seasons and prove to be "a good moth year". Unfortunately this was not to be and by the end of the year most recorders had reported a generally poorer year than of late. However, there were several highlights among which the re-discovery of the light orange underwing, Archiearis notha, and the record of the vine moth, Eupoecilia ambiguella, (a Notable/Nb species) new to Suffolk, are the most exciting. The real benefit of the warm weather in February was that those intrepid recorders who regularly venture out at this time of year were rewarded with pleasant conditions, that encouraged the less obvious early season moths to put in an appearance at their moth traps, rather than having tĂś endure almost freezing evenings in the usually forlorn hope of adding to our knowledge of the distribution of moths that are described as "common and widespread" and yet are but sparsely recorded in Suffolk. The small brindled beauty, Apocheima hispidaria, was recorded from the Ipswich Golf Club (SMG), Wolves Wood (TP) and Sicklesmere (SD); the spring usher, Agriopis leucophaearia, from Bromeswell Green (TP), Ipswich Golf Club (SMG), Minsmere (CA), and Wolves Wood (TP); and a little later in the year, in March, the lead-coloured drab, Orthosia populeti, at Eye (PK). RegulĂ¤r day-time surveying by Neil Sherman showed the orange underwing, Archiearis parthenias, to be well distributed in suitable habitat throughout much of the county. It was on one of these trips, to Wolves Wood, that Neil re-discovered the light orange underwing, Archiearis notha. This is a moth that has not been recorded in Suffolk for many years. Indeed there are no specific site records since Morley (1937) and his comment is of a species "less common than parthenias and apparently confined to clay woods containing much sallow". This is a slightly enigmatic and intriguing Statement as the larvae of the light orange underwing feed on Aspen, Populus tremula, and no other pabulum is recorded in the literature. Neil retained a voucher specimen so that the record could be confirmed by the Suffolk Lepidoptera Panel. On the 20th May an unusual Tortricid was noted in the moth trap at Landguard (NO) and as the tentative identification, although seemingly positive, was very unlikely the specimen was retained and the identification subsequently confirmed by Dr. J. Langmaid. The moth is the vine moth, Eupoecilia ambiguella, which is regarded as local and scarce and had previously been known in England only from Essex and Kent to Dorset and from Llantrissant in Wales. This species, which is widespread in the temperate zones of the Palaearctic and Indo-oriental regions, is said to be found frequenting moist heaths and scrubland, limestone scrub and open woods where the preferred larval foodplant Alder Buckthorn, Frangula alnus, occurs. Although not regarded as a migrant it seems probable that this specimen wandered across the Orwell/Stour estuary even though it is not recorded in north east Essex (Goodey & Firmin, 1992). Two other species that in recent years have also been recorded in this part of Suffolk and were at the time new
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to the county are both flourishing. The Oecophorid Tachystola acroxantha was reported in good numbers from two sites in Felixstowe (JN and NO) in 1998 and the least carpet, Idaea rusticata atrosignaria, (see Bradley, 1998 for nomenclature used in these notes) was particularly prolific at Landguard (NO) with 86 being recorded in July and August. It was also recorded elsewhere in Felixstowe (many by JN), at Ipswich Golf Club (NS/SN), Nowton (RE) and Barrow (AP). This species would seem to be well established in Suffolk at the moment and it will be very interesting to monitor its progress (or possible decline) in the next decade or so. Although the overall picture for 1998 was of lower numbers of moths being recorded and species generally being reported from fewer sites, there were species that defied the trend and occasioned comment for being more in evidence than they had been for the last year or two. Unfortunately there were also some species that were notable because their decline in 1998 seemed to be considerably greater than the norm. Of those species that were more in evidence some had been equally numerous in previous years. Among these are the knot grass, Acronicta rumicis, which was noted at Landguard (NO), Sicklesmere (SD), Ipswich (SG). Eye (PK), Dower House, Aldringham (DF), Ipswich Golf Club (SN/NS) and Rede Wood and Bromeswell Green (SMG); the latticed heath, Semiothisa clathrata clathrata (see Plate 7), from Nowton (RE), Ipswich (SG), Sicklesmere (SD) where intriguingly it was actually down by 78% on 1997, Bourne Park Ipswich, Shingle Street and Friday Street (SMG), Dower House, Aldringham (DF), Ipswich Golf Club (SN/NS) and Landguard (NO) where there were apparently three distinct flight periods, from the lOth to 2Ist May, the 29th June to 13th August and Ist to 19th September and the shaded fan-foot, Herminia tarsicrinalis, which is being shown to be much more widespread around those sites listed last year. Other species that caused comment on their frequency in 1998 were the lunar yellow underwing, Noctua orbona (see Plate 8), which was more plentiful in its known Breckland strongholds (RE, SD and DAC) and was also recorded from Wortham Ling (MB), Minsmere and Friday Street (SMG) and Burgh Churchyard (NS); the green carpet, Colostygia pectinataria\ the heart and club, Agrotis clavis, and particularly the privet hawk-moth, Sphinx ligustri. However, three species that in the last few years had also been noted as being more numerous than usual were specifically mentioned by a number of recorders as being very much less in evidence than expected and in some cases virtually non existent. These three are the common wainscot, Mythimna pallens, the heart and dart, Agrotis exclamationis, and the large nutmeg, Apamea anceps. The Situation with these three species in particular is summed up by the comment from Rafe Eley concerning the large nutmeg "I think on the whole perhaps my most common moth in a normal year. This year less than 2 dozen." I would urge all recorders to monitor these usually common species most carefully during the next few years so that it might be possible to determine whether such dramatic declines, more or less across the county, are nothing more than accepted cyclical Variation in populations or whether they continue at such a low ebb (or even lower) and indicate a serious deterioration in the viability of our moth fauna.
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NOTES ON SOME SUFFOLK MOTHS, 1998
Unfortunately the three spccies mentioned abovc are not the only ones in declinc at the moment. Several, like the drinker, Euthrix potatoria, the poplar hawk, Laothoe populi, and the a u t u m n thorns; A u g u s t thorn, Ennomos quercinaria, September thorn, Ennomos erosaria, canary-shouldered thorn, Ennomos alniaria, large thorn, Ennomos autumnaria, and even the feathered thorn, Colotois pennaria, to a lesser extent, are all continuing a trend that has been noticed for the last year or two. Others likc the c o m m o n e r yellow u n d e r w i n g s ; large yellow u n d e r w i n g , Noctua pronuba, lesser yellow u n d e r w i n g , Noctua comes, b r o a d - b o r d e r e d yellow u n d e r w i n g , Noctua fimbriata, lesser b r o a d - b o r d e r e d yellow u n d e r w i n g , Noctua janthe, and particularly least yellow underwing, Noctua interjecta caliginosa, together with the setaeeous hebrew character, Xestia c-nigrum, and the turnip, Agrotis segetum, have all shown a noticeable decline in 1998. However, as the degree of decline is very variable between recorders and there are a few exceptions to the general trend it is to be hoped that these species are just s h o w i n g a normal cyclical population Variation especially those where the resident stock is usually Supplement by immigrants f r o m the continent. T h e rare Pyralid, Platytes alpinella, (a p R D B 3 dspecies) was again recorded at Landguard ( N O ) and in 1998 this moth, which is very local and rather u n c o m m o n on coastal sandhills and shingle, was also f o u n d at Friday Street ( S M G ) ; C a v e n h a m and Icklingham Heaths (DAC), Lakenheath Warren (DAC), near Lakenheath at Pashford Poors Fen ( S M G ) , M i n s m e r e ( S M G ) and Tunstall C o m m o n (SMG). Pashford Poors was also an inland site for the d o g ' s tooth, Lacanobia suasa, which is more usually f o u n d in coastal areas and estuaries although it did m a k e its usual appearance in the W a v e n e y Valley at Mettingham (MB). Landguard (NO) also saw the second county record of the baisam carpet, Xanthorhoe birivata, on the 23rd July and c o n f i r m e d that the ground lackey, Malacosoma castrensis, (another R D B 3 species) is still flourishing in this corner of Suffolk. The S u f f o l k Moth G r o u p reported the water ermine, Spilosoms urticae, f r o m Rede W o o d in May and it was noted at D o w e r H o u s e , Aldringham (DF) in June. It is to b e hoped that these records following those f r o m one or two other sites in recent years herald a revival in the f o r t u n e s of this species. Another spccies that is featuring in more site reports in the last couplc of years, after a complete absence f r o m county records since the 1960's, is the orange footman, Eilema sororcula. This species of oak and beech woodland, with larvae feeding on various species of lichens found on these trees, was reported from Lineage W o o d s (TP), Ipswich Golf Club ( S N / N S ) and Hollesley C o m m o n (SMG). A moth that has not been recorded in S u f f o l k since 1979 the dark spectacle, Abrostola triplasia, (Bradley, 1998) was recorded at both D o w e r H o u s e , Aldringham (DF) and Minsmere (SMG). This species is much less c o m m o n and m o r e local than its congener the spectacle, Abrostola tripartita, and the two are less c o n f u s e d in the field than they have been in the literature where the specific names have been "regularly" exchanged over the years (until the latest list). A S u f f o l k M o t h G r o u p visit to Groton W o o d on the 15th M a y confirmed the presence of Fletcher's pug, Eupithecia egenaria (another R D B 3 species) in the areas of small-leaved lime, Tilia cordata, in the wood. On the same evening
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the poplar lutestring, Tethea or or, also came to light. Although by no means rare this Thyatirid is local in its distribution and more common in the southeastern counties of England where it follows the distribution of Aspen. It was also recorded from Ipswich Golf Club (SN/NS) and at East Bergholt at a joint meeting with the Essex Moth Group. Another member of the Thyatiridae, the common lutestring, Ochropacha duplaris, was recorded in July at North Warren (SMG). This comparatively common and widespread moth which occurs in birch woods and deciduous mixed woodland containing birch is probably under-recorded as it is not always readily identified being smaller and less distinctly marked than its relatives and it does not rest in the typical Position of most members of this family. The Ipswich Golf Club (SN/NS) and Dower House, Aldringham (DF) were the sites for the most recent records of the grass wave, Perconia strigillaria, in Suffolk. Previous records have been from Minsmere, Hollesley and the Dunwich Forest and although this species, with larvae feeding primarily on heather, broom and the flowers of gorse is found only sporadically away from its strongholds in Surrey, Sussex and Hampshire it is another species to look for through the heathlands in this part of Suffolk. It was also at the Aldringham site that the Kent black arches, Meganola albula, was recorded. The festoon, Apoda limacodes, is a species that is supposedly an inhabitant of mature beech and oak woodland and certainly the bright green, woodlouse-like larvae can be found clinging to the undersides of oak leaves, but virtually all recent East Anglian records have come from areas of scrubby oak, particularly fringing heathland. In 1998 it was recorded from Oxford Road, Ipswich (SL) and Ipswich Golf Club (SN/NS) and both sites maintain the current pattern. Following the huge numbers of marbled beauty, Cryphia domestica, reported from his Ipswich garden by Stuart Ling last year (Hall, 1998) a further increase was noted in 1998 with a total of 460 Coming to the trap between the 4th July and 26th September (a maximum of 64 on the 14th August). It will be most interesting to see whether this trend continues, levels out, or, as I would suspect, declines almost as rapidly as it increased as parasite populations catch up. Diligent day-time Observation was rewarded with further records of the lunar hรถrnet clearwing, Sesia bembeciformis, at Stowmarket and Combs Wood (NS) and much more excitingly with two records for the red-belted clearwing, Synanthedon myopaeformis, (a Notable/Nb species). This day Aying moth is usually found on the wing from late June right through July as the adults emerge from the pupae between 10.00 am and 12.00 noon. The presence of larvae is frequently indicated, as they feed internally in apple (and sometimes pear, peach and almond) trees, by small quantities of reddish frass which accumulate in bark crevices during the winter and early spring. The 1998 records came from Rushmere (NS) and Sudbury (CMcG). Another Suffolk record of the waved black, Parascotia fuliginaria, this time from Ufford (MF), does not really help in answering the question as to whether the scattering of sightings in Norfolk and Suffolk in the last few years represent a further population expansion of a species which until 1945 was rare in England or help to confirm suspicions that this species is an occasional immigrant. The Yponomeutid Acrolepiopsis assectella, the leek moth, is a one time migrant that appears, comparatively
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NOTES ON SOME SUFFOLK MOTHS, 1998
recently, to have become an established species with British records chiefly from the coastal counties of south-eastern England. Currently this species has pRDB3 status although it is a potential pest, a possibility that Stainton (1867) warned about before it was even known in Britain, and has warranted mention as such by Buczacki & Harris (1998: 306) and been the subject of question and answer in "Garden News" in November 1998. A singleton was recorded in Nowton Country Park (MH) in July. With several more records from Norfolk it is a species recorders may well encounter in greater numbers in the near future. On the same night the Tortricid Ancylis upapana, which is also designated pRDB3, was also recorded in Nowton Country Park. It is a distinctive species which is local and generally uncommon and apparently restricted to birch woods in the southern and south-eastern counties of England from Suffolk and Kent to Hampshire, Wiltshire and Oxfordshire. A score or so of migrant species were recorded from various sites across the county during 1998. The majority were noted at Landguard (NO) and some, like the silver Y, Autographa gamma, the diamond-back moth, Plutella xylostella, the rush veneer, Nomophila noctuella, which is also a breeding migrant and the dark sword-grass, Agrotis ipsilon, a species which can become a transitory resident, were widespread and often numerous (87 dark swordgrass at Landguard and 22 much further inland at Nowton (RE)) in their appearance. Two other Pyralids, Sitochroa palealis and the European com borer, Ostrinia nubilalis, are both migrants that become established as short to medium term residents. They were both recorded at Landguard and the latter was also seen in Eye (PK) and Aspal Close, Mildenhall (BC). The Breckland population of the tawny wave, Scopula rubiginata, is probably sustained by periodic influxes from the continent. This resident population was noted on several Breckland heaths (DAC) but the records from Ipswich (SL), Rushmere St. Andrew (JBH), and Wolves Wood (SMG) were almost certainly migrants. The gern, Orthonama obstipata, another migrant that is also a transitory resident, was recorded at Landguard and also in Berners Road, Felixstowe (JN). There were several migrant hawk-moths recorded in 1998 with the convolvulus hawk-moth, Agrius convolvuli, at both Landguard and Nowton (RE); the bedstraw hawk-moth, Hyles galii, at Dower House, Aldringham (DF); a death's-head hawk-moth, Acherontia atropos, larva at Sicklesmere (SD) (see Plates 1 & 2) and a number of the day-flying humming-bird hawk-moth, Macroglossum stellatarum, from Landguard, Nowton (RE), Minsmere (CA) and Monks Eleigh (AW). Probably the most spectacular migrant was the Clifton Nonpareil, Catocala fraxini, seen nearly opposite the Safeway supermarket, close to the River Waveney, on the Beccles by-pass (TWF). This sporadic migrant and transitory resident is presumed to have been resident in the Norfolk Broads (and other places) as late as the 1930's so it is not impossible for a temporary re-establishment to occur in the future. The preferred larval foodplant is Aspen. The white-point, Mythimna albipuncta, was recorded from Landguard, Felixstowe (JN), Minsmere and Knettishall Heath (SMG) and its relative the delicate, Mythimna vitellina, from Landguard. This was also the only site to record the scarce bordered straw, Helicoverpa armigera, and the bordered straw, Heliothis peltigera, although there were 13
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History, Vol. 35
of thc lattcr. There was only onc recorder who reported the vcstal, Rhodometra sacraria, in 1998 (RE) and hc had four at Nowlon. The pearly undcrwing, Peridroma saucia, was recorded at Landguard, Nowton (RE), Eye (PK), and Dower House, Aldringham (DF). Although there werc quitc a number of migrants reported in 1998 it was fewer that the year before and continued the decreasing trend since the recent peak in 1995. As in earlier years I am sure there have been sightings of both migrant and resident species that have not yet found their way to either of the county recorders or the Suffolk Biological Records Centre. Do pleasc send these and records for inclusion in future reports to either; Jon Nicholls, 18, Berners Road, Felixstowe, Suffolk, IP11 7LF; Tony Prichard, 3 Powling Road, Ipswich, Suffolk, IP3 9JR or the Suffolk Biological Records Centre, The Museum, High Street, Ipswich, Suffolk, IP1 3QH. Acknowledgments I thank all those recorders whose records and notes have helped to compile this report: Charlotte Anderson (CA), Maggie Brooks (MB), D. A. Coleman (DAC), Butterfly Conservation (BC), Stan Dumican (SD), Rafe Eley (RE), Malcolm Farrow (MF), T. W. Fairless (TWF), Dominic Funneil (DF), Steve Goddard (SG), J. B. Higgott (JBH), Paul Kitchener (PK), Stuart Ling (SL), C. McGrath (CMcG), Jon Nicholls (JN), Steve Noye (SN), Nigel Odin and Mike Marsh (NO), Adrian Parr (AP), Tony Prichard (TP), Neil Sherman (NS), Suffolk Moth Group (SMG), Arthur Watchman (AW) and in particular those who provided additional comments on numbers and local fluctuations which have been so helpful. References Bradley, J. D. (1998). Checklist of Lepidoptera recorded from the British Isles. Hants./Gloucs.: Bradley & Bradley Buczacki, S. & Harris, K. (1998). Pests, diseases & disorders of garden plants. (second edition). London: Harper Collins. Goodey, B. & Firmin, J. (1992). Lepidoptera of North Easl Essex. Colchester. Colchester Natural History Society. Hall, M. R. (1998). Notes and comments on some Suffolk moths in 1997. Trans. Suffolk. Nal. Soc., 34: 91. Morley, C. (1937). Final catalogue of the Lepidoptera of Suffolk. Ipswich: Suffolk Naturalists' Society. Stainton, H. T. (1867). On thc habits of Acrolepia assectella, Zâ€ž a species not yet found in Britain. Entomologist's mon. Mag. 3: 257-258. M. R. Hall (MH) Hopefield Scole Diss Norfolk IP21 4DY
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Plate 1: Death's-head Hawk Moth. Acherontia (p. 83). A regulĂ¤r migrant to Britain (p. 4).
atropos L.. Sicklesmere, 1998
Plate 2: Death's-head Hawk Moth larva. Acherontia atropos Lâ€ž Sicklesmere. 1998 (p. 83). In times past collectors would pay potato pickers to find larvae so that they could obtain fresh specimens (p. 4).
ÂŁ Q Plate 7: Latticed Heath, Semiothisa clathrata clathrata L., a Biodiversity Action priority species which did well in 1998 (p. 80).
Plate 8: Lunar Yellow Underwing, Noctua orbona Hufnagel, a Biodiversity Action priority species which was plentiful in its known Breck strongholds in 1998 (p. 80).