Girton Birdwatch - August 2009
June/July are relatively quiet times for birds so I thought I'd 'cheat' and devote this piece to another set of 'flyers': the moths and butterflies. This decision was prompted by two events: the 'invasion' (no other word does it justice) at the end of May of millions of Painted Lady butterflies from the Continent, and a rather splendid evening/early morning spent trapping moths in the garden of the Miller/Wilson home.
The Painted Ladies were difficult to miss. The first I heard of them was via Philip Sadler, the owner of Oakington Garden Centre, who watched in amazement as hundreds of these fast-flying insects streamed past his doorway. Out walking the same day every butterfly I saw was a Painted Lady. We were not alone. Ever since the Bank Holiday week-end the organisation Butterfly Conservation had been receiving reports from people all over Britain about the large numbers of these butterflies which had been seen passing overhead, for hours on end. They were first spotted off Portland Bill in Dorset on May 21st, after which thousands were seen flying north at numerous locations across southern England, from Cornwall to East Anglia. The sunny weather over the Bank Holiday brought hundreds of new sightings from as far north as Dumfries and Galloway in Scotland, to the estimated 18000 flying past Scolts Head Island on the Norfolk coast on 27th May. The next day the butterflies were still passing overhead, at a rate of 50 a minute, along a 400 metre front - hundreds were even to be found in central London. The Painted Lady - its upper wings are a marbled pinkish buff, with black and white tips in case you missed them - is a regular summer migrant to these shores from the Mediterranean, and they often arrive in a rather faded and tattered condition. The number of immigrants varies considerably from year to year but it is probably safe to say that we have just witnessed a once-in-a-life-time event.
Scientists had been predicting an unusually large migration since late winter. The butterflies originate in the Atlas Mountains of Morocco and it was here that heavy winter rains allowed particularly good germination of the caterpillar food plants. One Spanish researcher reported seeing hundreds of thousands emerging in mid-February and beginning their long flight north; large numbers were seen in Spain during April and a few weeks later they had reached France. Then, in May, literally millions fluttered into Britain like living confetti, providing a spectacular and heart-warming start to the summer.
While here, the Painted Lady lays its eggs singly on thistles or nettles - so save a patch! - with the emerging caterpillars living in silky webs that they weave among the leaves. The butterflies emerge from the pupal, or resting, stage in late summer and most of these will migrate southwards in autumn. Those that stay behind don't usually survive the winter, although nowadays that is presumably not a foregone conclusion. The butterfly to be watching out for at present - there are increasing numbers around the village - is the Comma. This large butterfly is hard to miss as it has distinctive tattered wings, which are a striking orange-brown. The white 'comma', from which it gets its name, is easily seen against its smoky brown underwings.
I must admit that, until recently, I have preferred butterflies to moths. Is it that moths have 'something of the night' about them (although not all moths are night-flying) or is it that they seem more 'scratchy'? Are butterflies more beautiful? I used to think so, but now I am no longer so sure. In mid-May, Dave Heath, who has in the last couple of years added an enthusiasm for moths to his repertoire - is there no end to the man's talents? - brought a captive, but soon to be released, Elephant Hawkmoth to show me. There are nine species of hawkmoth breeding in Britain (I was already familiar with the pink-and-black-banded Privet hawkmoth), but perhaps the Elephant hawkmoth is the prettiest. It is an exquisite blend of intense bands of pink and soft olive greens and browns, and well-worth staying up to see. At the end of the month Dave set up his light-box in the Miller/Wilson garden. A light-box is a very bright sodium (?) bulb enclosed by glass and flanked with large egg-trays to provide cover and resting places for any moths attracted. We commenced our vigil at about 11.30pm and we were still examining moths at 2am. There are more than 2000 species of moth in Britain and - despite less than ideal conditions - we attracted a wide range including: Small Emerald, Clouded Border, Brimstone, Peppered, Willow Beauty, Clouded Silver, Scalloped Hazel, Iron Prominent, Pale Tussock, White Ermine, Buff Ermine, Muslin, Heart and Dart, Flame Shoulder, Setaceous Hebrew Character, Angle Shades, Dark Edges, Treble Lines, Straw Dot, Snout and, pleasingly, the aforementioned Elephant Hawkmoth. None of these moths is particularly rare and there are hundreds of them out there!
The evening/morning was made all the more memorable by the hospitality offered by Chris Wilson - Linda was away! - who had prepared a delicious Nigel Slater-inspired Butterbean, Fennel and Sausage casserole (there were five of us) which was washed down with some bottle-conditioned refreshment. For some reason I was reminded of a book I bought when first coming to Cambridge: Breadlines, by David Mabey, brother of the naturalist Richard, in which is recorded in diary-form, several years of an idyllically bucolic Suffolk existence spent eating and drinking (Adnams beer figured prominently) and enjoying the other delights of a country life. The 'mothing', the casserole and the company, in turn, made me 'glad I lived around here'.