A REVIEW OF BRITISH FĂœR
LEPIDOPTERA
1960
b y BARON DE WORMS.
THE story for 1960 is indeed a very different one from its predecessor. Following on the phenomenally warm season of 1959, that of 1960 was one of almost unbroken dullness with very few really hot spells and it eventually ended in one of the wettest autumns on record. It opened with, on the whole, a mild winter with only one sharp spell in mid-February. Butterflies began appearing at about their normal dates, while the sallow bloom was well up to its usual time of maximum, the end of March. A very welcome feature of the early spring was the reappearance in numbers of the Holly Blue (Celastrina argiolus, Linn.). It is manv years since this most attractive little butterfly had been seen in such plenty. For quite a long period it had been almost absent and many people were wondering if we would ever see it again in its former abundance. It was probably the previous dry autumn that helped it to produce such a bountiful first brood which was eventually repeated when in the later summer it was again present in hundreds in most areas over Southern England. This was one of the bright spots of this rather melancholy year. The two Pearl Bordered Fritillaries (Argynnis cuphrosyne, Linn., and A. selene, Schiff.) were out at their normal periods in early and late May respectively in fair quantity together with the Orange-tip (.Euchlo'e cardamines, Linn.). High hopes were raised at the end of this month when two examples of the Crimson-speckled Footman (Utetheisapulchella, Linn.), v/ere obtained on the south-east coast. Since it was apparently in great plenty in Southern Europe at the time, it was thought that this might be a prelude to an invasion or an autumn emergence, which has not been seen in this country for over 50 years, but no more appeared. In fact, this first half of the year was singularly devoid of migrant species, even among the butterflies, while the Rush Pearl (Nomophila noctuella, Schiff.) which came over in thousands in 1959, was virtually absent in 1960. June, however, was a much better month and the latter half brought some of the best weather of the whole season. About the middle of the month therewas a remarkable emergence of the Alder Kitten (Cerura bicuspis, Borkh.), almost record numbers being seen at light in its restricted localities, mainly in Sussex, while the last week of June brought an extraordinary apparent immigration of the Rannoch Looper (Itaine brunneata, Thunb.). At least eight examples were recorded, chiefly from the southeastern part of England and one as near London as Wimbledon. All the specimens were appreciably larger than those normally found in the Highlands, which points to a foreign origin, especially as
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BRITISH LEPIDOPTERA
this insect has in bygone years been notorious for turning up in the most unexpected places. The same period saw the capture of several of the Large Footman (Lithosia quadra, Linn.) evidently migrants too, as the normal date for this insect's appearance is the end of July. The Heart and Dart (Agrotis exclamationis, Linn was in prodigious numbers also during the last davs of June. Düring early July the Rest Harrow (Aplasta ononaria, Fuessl.) and the Pale Ochraceous Wave (.Sterrha ochrata Scop.) were in unusually large numbers on a restricted part of the Kent coast and it is indeed good news to know that the latter species has reappeared on the Suffolk coast together with the Tawny Wave (Scopula rubiginata, Hufn.). In mid-July some unusual migra in the Highlands were captured. These included the Striped Hawk (Celerio livornica, Esp.), the Spotted Clover (Heliothis scutosa, Schiff.) and the Death's Head (Acherontia atropos, L two of which were taken in the same regions in the following September. Butterflies during this period of the year were well up to average, in particular the larger Fritillaries and the White Admiral (Limenitis Camilla, Linn.), but migrant species we extremely scarce and very few Clouded Yellows (Colias croceus, Fourcr.) and Painted Ladies (Vanessa cardui, Linn.) were observed throughout the summer months. A single example of the Scarce Silver Y (Plusia interrogationis, Linn.) was taken in the Home Counties in early August, again pointing to foreign immigration, since its normal home is in the north of England and the Highlands. The Chalk-hill and Adonis Blues (Lysandra coridon, Poda., a L. bellargus, Rott.) were in good numbers, while the various species of the Vanessidae, especialy the Small Tortoiseshell (Aglais urticae, Linn.) were much below their average number
In early September a specimen of the Mediterranean Brocade (Prodenia litura, Fabr.) was taken in North Norfolk, probably rare migrant. It was obtained in the same localitv as the Slender Burnished Brass (Plusia aurifera, Hübn.), in 1959 and the Dorset Straw (Heliothis nubigera, Scop.) in 1958. This part of the year witnessed the start of a truly remarkable influx of the Convolvulus Hawk (Herse convolvuli, Linn.) which spread all along the sou coast of England and well inland to the most northerly limits. In such places as the Scilly Islands it was in great abundance, sometimes dozens being seen in a single night. This migration went on well into October. Another species which probably had not been seen in such numbers since before the War was the Delicate Wainscot (Leucania vitellina, Hübn). This insect too was very common on the south-western area, mostly in coastal regions during September and October. The White-speck Wainscot (Leucania unipuncta, Haworth) was once more quite numero among the south-western seaboard. The Red Admiral (Vanessa
BRITISH
LEPIDOPTERA
491
atalanta, Linn.) was again plentiful in the west during the autumn, probably on a southern migration. Only one specimen each of the Bedstraw Hawk (Celerio galii, Rott.) and the Silver-striped Hawk (Hippotion celerio, Linn.) were recorded in the south during the late summer. The autumn proved distinctly unproductive, except for a few of the Scarce Bordered Straw (Heliothis armigera, HĂźbn.) and it also saw the spread of Blair's Pinion (Lithophanc leautieri, Bdv.) to Dorset and Devon, while a specimen was even taken as far inland as Reigate. Two examples of the Black-streaked Pug (Eupithecia pkoeniceata, Rambur), discovered in South Cornwall in 1959, were taken in that area in this period in 1960 with another specimen in South Devon, thus pointing to its being well established on that part of our coast. T h e White Pyrale, the Scarce Olive Tree Pearl (Palpita unionalis, HĂźbn.) was also once more quite common in the South during the autumn. After a disappointing start and very wet summer, the latter months of 1960 proved very interesting and most productive as regards migrants, though most of the commoner butterflies were distinctly scarce throughout the year.