Suffolk Lepidoptera in 1973

SUFFOLK LEPIDOPTERA IN 1973 H . E . CHIPPERFIELD

mild winter was followed by a cold spell in early February but a warmer evening on 19th brought out a number of spring geometers including the Early Moth (Theria rupicapraria Schiff.), Pale Brindled Beauty (Phigalia pedaria Fabr.), Dotted Border (Erannis marginaria Fabr.), and March Moth (Alsophila aescularia Schiff.). T h e Orange Underwing (Archiearis parthenias Linn.) a day-flying moth was well out in Dunwich Forest on 24th March and several members of the "Quaker" family appeared about the same date. The emergence of the early spring moths is usually a little later in Suffolk than in the southern counties.

Hibernated Peacock (Nymphalis io Linn.) and Small Tortoiseshell (Aglais uriicae Linn.) butterflies were flying in the sunshine on 23rd March and the Green-veined White (Pieris napi Linn.) was observed at Butley Creek on 29th April during an outing of the Bird Section to that area. Unfortunately the Holly Blue (Celastrina argiolus Linn.) has again become very scarce. I only saw one example in Walberswick on 18th June, which is a very late date for the first brood. I saw none of the second brood.

Other observers report the same scarcity.

ANOTHER

On 5th June I paid the first evening visit to Abbey Farm, Letheringham, with Messrs. W. G. Buncombe and John Shackles in connection with the farming and wildlife survey undertaken by the Nature Conservancy. Unfortunately the night became clear and cool and very few insects were attracted to our lights. However, on later visits numbers improved considerably. Redgrave/ Lopham Fen on 6th produced several specimens of the Marsh Pug (Eupithecia pygmaeata HĂźbn.). This is an addition to Mr. C. W. Pierce's list of moths for the Trust's Reserve. On 20th July I was able to confirm the presence of this species when I found some larvae feeding on Water Chickweed (Myosoton aquaticum). During the Society's meeting at Tattingstone on 9th June a Red Admiral (Vanessa atalanta Linn.) was seen by Mrs. Kershaw. Subsequently this migrant butterfly was very common. Also found on this outing was a larva of the Small Yellow Underwing moth (Panemeria tenebrata Scop.) on Mouse-ear Chickweed.

Larvae of the Ground Lackey Moth (Malacosoma castrensis Linn.) were still very small on the sah marshes at Aldeburgh on 18th June and not as plentiful as usual. These larvae often survive submergence during hibernation in their dense web during the winter.

On 22nd June, Mr. Brown of Lowestoft Field Club reported a Lobster Moth (Stauropus fagi Linn.) at the lights of Brooke Marine at Lowestoft. This is a very unusual place for such a woodland

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species. A Broad-bordered Bee Hawkmoth (Hamearis fuciformis Linn.) was seen hovering over catmint and valerian flowers on 24th June at Walberswick.

A specimen of the Least Carpet Wave (Sterrha vulpinaria H.-S.) came to mercury-vapour light on 16th July. This is the second example of the insect to be recorded at Walberswick as Mr. Brian Elliott found it on 4th August, 1971. It is common on both sides of the lower Thames estuary and also occurs at Portland, Dorset, and Torquay and there are old records of single specimens at Stowmarket and Felixstowe.

The British Entomological and Natural History Society held a field meeting at Walberswick during the week-end of 28th-29th July. The local specialities, the White-necked Wainscot (Nonagria neurica Hübn.), Fenn's Wainscot (Arenostola brevilinea Fenn), and Powdered Wainscot (Simyra venosa Borkh.) were all in evidence and the Fen Wainscot (Arenostola phragmitidis Hübn.) was abundant, but a visit to Southwold beach had to be made to see the Lyme-grass Wainscot (Arenostola elymi Treits.), the Shore Wainscot (Leucania litoralis Curt.) and the Coast Dart (Euxoa cursoria Hufn.). The last three inhabit the sandhills and the disastrous flooding by the sea at Walberswick during the last two years has no doubt greatly reduced the populations of these species.

The Lucid Pearl Moth (Perinephela perlucidalis Hübn.) was only discovered in the British Isles in 1951 at Wood Walton Fen in Huntingdonshire. It was first seen at Walberswick in 1967 and has been seen in most years since then. A further example seen on 3rd August suggests that it is well established in this district.

In Dunwich Forest on 16th August there was not much to be seen on the wing but two small pine-feeding species Purdey's Shoot (Clavigesta purdeyi Durr.) and Sprinkled Scots-fir Argent (Cedestis gysseleniella Zell.) could be disturbed from the pine trees in numbers.

When Mr. George Baker and I paid our fourth visit to Letheringham on 17th August we were joined by Mr. and Mrs. A. Watchman and other members of Ipswich Naturalists' Society. Three mercury-vapour lights were run on this occasion and a total of eighty-eight species of moths was recorded. These were mostly common species but the total included the Sallow Kitten (Harpyia furcula Clerck.), four species of Prominent, and six kinds of Thorn including the August Thorn (Ennomos quercinaria Hufn.) which is not very common in Suffolk. There were also two interesting pyralid moths, the Tabby Knot-horn (Euzophera pinguis Haw.) whose larva feeds on the inner bark of ash, and continued infestatioii usually kills the tree, and the Pine Knot-horn (Dioryctria abietella Schiff.) which has two types of life-cycle. Larvae hatch-

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ing in early summer feed inside pine cones whilst those hatching later in the year feed first in the cones and after hibernation they burrow into the shoots and feed on the pith or in the buds.

In late August the Peacock Butterfly (Nymphalis io Linn.) was very common and September saw a great emergence of the Red Admiral (Vanessa atalanta Linn.) the offspring of earlier immigrants from the Continent. On a small heap of rotting banana skins about 6 inches Square I saw twenty of these fine butterflies.

Similarly the Small Tortoiseshell (Aglais urticae Linn.) swarmed on its favourite flowers and Mr. and Mrs. Prangnell called me in to see about forty of these insects on three Ice Plants in their Walberswick garden. DĂźring the same period the Silver-Y moth (Plusia gamma Linn.) was very common both by day and night, hovering over flowers. They are also attracted by bright lights and on the morning of 6th September there were over 200 in my mercury-vapour trap. This moth is a resident species but its numbers are often greatly increased by immigration.

In spite of a very extensive Are on Walberswick Common in 1972 the Grayling Butterfly (Eumenis semele Linn.) and the Small Copper (Lycaena phlaeas Linn.) were present in reasonable numbers, but the Silver-studded Blue (Plebejus argus Linn.) could not be found in its former habitat at Wenhaston. However, Mr. Wilfred George discovered a flourishing colony of this butterfly near Dunwich and Mr. S. Beaufoy saw it in good numbers on a heath near Ipswich so perhaps its numbers will build up again on our Suffolk heaths where it used to abound.

Of our other butterflies I have heard of no SufTolk records of any of the fritillaries but a few of the Painted Lady (Vanessa cardui Linn.) were seen in several widely separated parts of the county.

Mr. Beaufoy reported several Comma (Polygonia c-album Linn.) near Ipswich and Mr. A. C. Hubbard of Woodbridge saw two Clouded Yellow (Colias croceus Fourc.) at Kirton Creek near Felixstowe in late August.

Mr. George Baker of Reydon found a Convolvulus Hawkmoth (Herse convolvuli Linn.) in September. Larvae of the Bedstraw Hawkmoth (Celerio galii Rott.) were reported from the Lincolnshire coast and quite a number of these two immigrant moths were found in the western counties during the summer, but I have heard of no more from Suffolk this year.

A further visit to Letheringham on 28th September added eight more species to the list in connection with the farming and wildlife survey. As was expected, several of the common autumn moths put in an appearance, but I was surprised to see single examples of the Large Thorn (Ennomos autumnaria Wemb.) and Barred Sallow (Tiliacea aurago Schiff.). T h e former has been a

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fairly regulär species in the Stowmarket area since 1952, although Claude Morley considered it to be "so rare as to be doubtfully indigenous" in 1937. The Barred Sallow is associated with beech which is not a native Suffolk tree.

Single specimens of the Purple Emperor (Apatura iris Linn.) and White Admiral (Limenitis Camilla Linn.) butterflies were reported from West Suffolk woods. Both these species have become very scarce in Suffolk and as they inhabit deciduous woods it is most important for their survival that our remaining native broadleaved woodlands are saved from destruction. Several other woodland butterflies have also become very scarce and are in peril of joining the endangered species list.

II. E. Chipperfield, F.R.E.S., The Shieling, Polmer s Lane, Walberswick, Southwold, Suffolk.