Two Visits to Suffolk during 1959

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THE MEADOW

BROWN

It will be seen that the general pattern is the same as in 1958 in that there is a large excess of males over females at the beginning of the season, the reverse being the case at the end of the summer.

The great difference between the relative numbers collected in the two years lies in the time of emergence. In 1958, which was wet and cold, the first butterflies did not appear in any numbers until the end of June, while in the hot and dry summer of 1959 there were considerable numbers Aying as early as the middle of June, and at the end of June and beginning of July they were very plentiful indeed. In 1958, during the period 21st to 30th July, the numbers of males was still in excess of the number of females, while in 1959 the number of males feil below the number of females during the period 9th to 18th July. At the end of August, 1958, the insects were still quite plentiful, while in 1959 the Aying season was over very early, only 5 butterAies being captured on 18th August. This difference between the two years was, no doubt due to the very different weather conditions ; the hot spring of 1959 caused the butterAies to start emerging about a fortnight earlier than in 1958, and the continued sunny weather enabled the insects to be more continuously active than they were during the previous summer. Their length of life in 1959, therefore, was probably shorter, and this would result in a dearth of the insects in the late summer.

TWO VISITS TO SUFFOLK DURING 1959 by

BARON DE W O R M S

SUFFOLK indeed had its fair share of the recent phenomenal summer and collectors who visited that part of England reaped a very good harvest of the lepidoptera of those regions. Once more I joined Mr. Edgar Hare on July 14th when as before we made our headquarters at Southwold. That night we put up our m /v generator on the bank overlooking the extensive marshes between Walberswick and Dunwich, but conditions were far from favourable and we only saw 16 species of moths at our light, none of which was of any special note. The next day proved as usual very bright and warm when we explored the marshy area further. The chief

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feature was the abundance of the Gatekeeper butterfly (Maniola tithonus Linn.). I have seldora seen so many in a single day.

Every bramble bush was alive with them. On the heaths the Grayling (Eumenis semele Linn.) was already just appearing, but a hunt for the Silver-studded Blue (Ple'oeius argus Linn.) produced very meagre and disappointing results. Only in one very restricted loeality did we find a handful, whereas some ten years ago this delightful little insect was in quantity all over the heathland round Blythburgh and Walberswick. It is to be feared that it has disappeared from most of its old haunts in that area owing to the rapid encroachment of bracken. The species may soon only be confined to the heaths in the southern part of the county.

For our second night we tried our light on the edge of the marsh bordering a small wood which we sugared with very poor results.

However, our lamp placed in a sheltered spot among the reeds produced a fine assortment of insects and we counted nearly 60 species by 1 a.m. By far the commonest was the Triple-spotted Clay (Amathes ditrapezium Borkh.) of which we recorded over thirty, mostly in very good Order. The usual marsh species were well to the fore, in particular the Fen Wainscot (Arenostola phragmitidis Hübn.). The Drinker (Philudoria potatoria Linn.) was in numbers, while the most numerous of the Geometers was the Sharp-angled Carpet (Euphyia unangulata Haworth). But we saw no sign of the Sussex Wainscot (Nonagria neurica Hübn.) which was taken plentifully a few days later by other collectors.

We also ran a trap in a garden at Blythburgh belonging to the owner of our hotel. The second night provided 35 species with nearly 100 individuals which included a Läppet (Gastropacha quercifolia, Linn.), two Privet Hawks (Sphinx ligustri, Linn.), several Garden Tigers (Arctia caja, Linn.), an early date for this species and a Varied Coronet (Hadena compta, Fab.), which is becoming increasingly prevalent in the County. On our return journey on July 16th we halted at a flower nursery on the outskirts of Ipswich and picked some dried heads of Sweet William which were füll of the young larvae of this local moth.

My next expedition to Suffolk proved even more fruitful. On August lOth, I again motored to Walberswick this time to stay with Prof. J. Dacie who was renting a house for his family's holidays.

Düring the previousfivedays he had been running a m /v trap in the garden not far from the marshes with remarkable results, obtaining on some occasions as many as 500 macrolepidoptera in a night.

Among the 155 species of the Macros he recorded on the eight occasions on which he ran his light the most outstanding captures was a fine female of the Bedstraw Hawk (Celerio galii. Rott.).

So that my appetite was whetted and not without reason. For the first night we ran my portable m /v light on the edge of the marsh in the same loeality as in July, but to much better advantage as, though the night was wet, moths came early Streaming to the light

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tili by 11 p.m., we had noted 65 species. Among the more interesting were the Pine Hawk (Hyloicus pinastri, Linn.), several fine Powdered Wainscots (Simyra albovenosa, GĂśeze), quite a run of the Twin-spotted Wainscot (Nonagria geminipuncta, Haworth), the Brown-veined Wainscot (Nonagria dissoluta, Treits.), including several melanic examples. Shortly afterwards came Fenn's Wainscot (Arenostola brevilinea, Fenn.), together with some pale and varied Coast Darts (Euxoa cursoria, Hufn.), a number of the Starwort (Cucullia asteris, Schiff.), the Gold-spot (Plusia festucae, Linn.), the Dusky Sallow (Eremobia ochroleuca, Esp.), and a few of the Least Yellow Underwing (Triphaena interjecta, HĂźbn.), the Rosy Minor (Procus literosa, Haworth), and the little Rufous Wainscot (Coenobia rufa, Haworth). Increasingly heavy rain made us return home early where we found Prof. Dacie's trap alive with nearly all the species mentioned above as well as a lot of the Prominents, especially the Swallow Prominent (Pheosia tremula, Clerck), altogether a fine harvest.

August 1 Ith turned out a dull and windy day which we spent Walking along the sandhills towards Dunwich. Larvae of the Starwort (Cucullia asteris, Schiff.) were abundant and in all sizes on the sea aster. By dint of careful searching of patches of yellow bedstraw we found a few half-grown larvae of the Hummingbird Hawk (Macroglossa stellatarum, Linn.), which fed up quickly and produced imagines in September. Butterflies seen included the Peacock (Vanessa io, Linn.), lots of the Small Tortoise-shell (Aglais urticae, Linn.), and the Common Blue (Polyommatus icarus, Rott.).

That night we once revisited the spot of our previous exploit where the wood borders the marsh, but once again sugar proved a failure. However, we were kept busy tili after midnight with a large number of visitors to the sheet, recording in all 58 species, many of which were the same as on the previous night, especially the Powdered and Brown-veined Wainscots. But several other species put in an appearance, including the Archer's Dart (Agrotis vestigialis, Rott.), the Sallow Kitten (Cerura furcula, Linn.), the Scarce Footman (Eilema complana, Linn.), the Oak Hook-tip (Drepanabinaria, Hufn.), the Beautiful Yellow Underwing (Anarta myrtilli, Linn.), and the Magpie (Abraxas grossulariata, Linn.). That night my host's trap had nearly 700 visitors including the local Pyrale, the Yellow Straw Pearl (Evergestis extimalis, Scop.).

I returned to Surrey next day well satisfied with my trip which was the most successful I had experienced in that part of Suffolk.