Some Meanderings on Lepidoptera.
§1. How to attract any Moth.
24th November 2015. We’re lucky that we don’t get colds or sore throats very often. By which you may certainly infer that we have both at the moment. However, they’re well on the mend, because we have nursed them by staying in for a couple of days, and doing practically nothing except drink endless mugs of tea and read books. Of course, that should be endlessly drinking mugs of tea – but I quibble; the usage of the absurd ‘endless cups of coffee’ &c. is far too well entrenched for someone of my age to take up the cudgels against. No; that won’t do; let’s try: …far too well entrenched up against which someone of my age should take up the cudgels. H’mm. I think that’s probably more correct, but it looks – and actually sounds – pretty damn silly when you read it out. Also, it occurs to me that the image is already going up the screen out of sight, and by the time I’ve actually got round to describing it (assuming anybody will ever read these maunderings) it might have totally disappeared. Very well then. We shall delete all we have written so far and begin again. OK – here we go!
By chance, several of the books we have re-read lately are devoted to entomology in general and lepidoptera in particular. This was rather poignant, as although this November had been exceedingly mild, we have just had our first frosts, so the lepidopterous fauna of the vicinity will be receding rapidly. So there won’t be all that much opportunity of studying them in their natural habitat for the next few months, at least in their adult form. That being the case, we reproduce the image above. It is dated 8th August this year, at 8:00 p.m. when it would of course have been daylight. Therefore, the moth must have come in the night before & spent the day in the kitchen. It can only be the Old Lady Moth, Mormo maura, but what I find so satisfying (the best word I can produce offhand) is that she – him – it, has taken up repose on the kitchen work-surface, which happens to be patterned in a way ideally suited to the procrypsis, or camouflage, of the moth.
But I hear you ask, where else should a moth repose in a kitchen, other than on the optimum background that will help conceal it? I fully agree. I should have been more concise, and explained why I was possessed of such child-like satisfaction. It was because Mormo maura, and no other species, had come through the window, in order to repose on a patterned work surface as if it had been put there for that species alone!
The rest follows inevitably. I have always wanted to see a living Oleander hawk moth. I feel sure the real insect must be far more spectacular than any photo. Therefore, all I have to do, is to install in my kitchen, a work surface coloured and patterned in a manner closely based on the said moth, as above. Then, assuredly, a pristine example of Daphnis nerii (rare as it is in the U.K.) will find it irresistible, fly in through my kitchen window, and settle on what it thinks is its natural background. Ta-raah!
Or, I suppose, I could just print out a large copy of the above image, and leave it lying around in the kitchen. But it wouldn’t be the same, would it? 8^)
§2.The Gypsy Moth – Lymantria dispar
Day-flying male, top. Female does not fly.
One is not allowed to have the Gypsy Moths any longer, as their caterpillars are a pest of fruit trees and such. Lymantria dispar used to be very popular e.g. in schools, as they would breed easily, were little trouble, even tolerant of neglect, and the children could, in due season, witness the fascinating stages of metamorphosis &c. However, even though the Gypsy Moth is supposed to have been extinct in the British Isles since the middle of the 19th century, it is, alas, very much alive and kicking in the U.S.A. Not a native of North America, it was taken there (Massachusetts) around 1870, for possible use in a proposed silk industry. Some escaped, and found the whole territory very much to their liking. Since it was not native to North America, there were no obvious natural parasites to keep its numbers down. So since then, it has been defoliating orchards and being a terrible pest. Wikipedia has an animated map of its spread since 1900. Countless millions of dollars have been spent in attempts to eradicate it, or even just to stem its advance. To no avail.
We acquired some Gypsy Moth eggs back in the early 1980s. They hatched & the larvae were fed on Hawthorn, IIRC. They grew, flourishing greatly, and then pupated. Towards the end, some larvae grew much bigger than others. These were, naturally, the females. 8^)
But no – in this species, the females don’t fly, though they still have wings. The smaller & highly dimorphic males do fly. While the fully grown larvae were in the process of pupation, it so happened, that I left a shirt to dry on the back of a chair, near the table on which the boxes of larvae were set. It was a week or so later that I donned the shirt in order to go to a gig. As I put it on, I felt something cool on my back. It was the fine, fat pupa of a female, who, as a full-fed larva, had escaped from the boxes, explored, and decided the back of a white shirt was an ideal site to pupate. Of course, there have been many instances of pupae being discovered in unexpected places (see below); indeed, my entomological hero, P.B.M. Allan *, once found a pupa in his hat – undoubtedly just as logical as a shirt – in fact, much more so, if you think about it.
Many eggs were laid in the boxes, to be kept for next year, and so, without thought, the rest of the stock – adults and remaining pupae – were tipped out into the garden, under a hedge. A hawthorn hedge, actually. No further thought was given to them, until a fine day next spring, when the kids were playing in the in back garden, and my son called me to report ‘a black butterfly’. Interested, I went to see. To my horror, it was a male Gypsy Moth. I went quite cold, then thought a bit, and went colder still. Suppose… but no; it wasn’t possible. Lymantria dispar was, after all, extinct in the U.K. Or at least, supposed to be. But what if I had inadvertently founded a colony?
Fortunately for me – and the whole country! – there was no return of L. dispar. Not then, at any rate. While writing this, we discovered that in 1995 and 2005, colonies of Gypsy moths had been found in London and Buckinghamshire, respectively. I have nothing to do with those either, I assure you!
* Patrick Bertram Murray Allan, M.B.E. (1884-1973) was a man distinguished by many impressive and diverse accomplishments quite apart from entomology. I had intended to put here a link to his Wikipedia article, so that you can read about him yourself. But there seems to be no article for him! If so, this is an intolerable situation, which must be remedied as soon as possible, even if I have to do it myself. I have five of his books (he wrote quite a few more), and a couple of years ago, while looking for some information on Allan, chanced across an 18-month-old auction list. Up for sale had been his entire set of hand-written entomological diaries, from the 1890s to (I think) the late 1950s or even into the 60s. They had been sold for slightly under £500. In a way, we are glad that we had been unaware of that sale, as otherwise we would have become obsessed with getting them; or at least, the opportunity to inspect them. Who bought them, we have no idea. Hopefully, they went back into his family, or if not, a suitable academic library which furnishes access to them even if the enquirer is not themselves an academic.
§3. The Privet Hawk Moth – Sphinx ligustri.
A fine insect, if ever there was one. We had a large privet hedge in the garden of that house as well, and that was just as well, for the 12 eggs we had bought in (NOT ova, please – Allan was most explicit on that point) produced twelve buoyant and active larva. A plastic box was all very well for a few days, but we ended up with 12 large open-topped glass jars, into each of which was put several privet twigs, each bearing eight to twelve leaves. As time went by, this process had to be repeated twice a day, and the cleaning & cycling of many jars in order to ensure cleanliness became quite a chore. But anyone who has undertaken to rear (a) very many caterpillars of a small moth, or, as here, (b) just a dozen caterpillars of a large moth, will know exactly what I’m talking about. Eventually, after attaining a most impressive size, they dwindled slightly, and fed much less. Accordingly, three plastic buckets were provided, containing very slightly moist potting compost, and the larvae were transferred in sequence, as each in turn displayed a duller green and even a hint of brown, to the buckets. We had read that a larva will, from time to time, find even a meticulously-arranged Pupation Facility, such as I had provided, unsatisfactory for reasons known only to itself, and so emerge, and look for ‘a better place’. Therefore, sheets of hardboard were placed over the buckets, and weighted down to give any such larvae second thoughts.
Nothing was supposed to happen until the following summer. However, Dame Nature is sometimes unpredictable in her Ways, as we discovered about a month later. Did I tell you that the folding push-chair was kept near the buckets? Well, it was, and one busy Saturday morning in Autumn, I was up in the city centre in Mothercare, with my very young daughter in the push-chair, to get some things for her, when I was distracted by cries of alarm and agitation. Glancing idly towards the disturbance, I saw several women gesticulating and pointing to something on the floor. Approaching, we saw a magnificent but fatally injured female Privet Hawk crawling helplessly on the floor of Mothercare, having been most foully and horribly TRODDEN ON by a vile and persistently evil customer. The poor thing had emerged very soon, only after about a month, somehow escaped from the bucket, and crawled onto the pushchair to expand its wings. It had then stayed there, probably awaiting a male, poor thing, until it was transported to Mothercare.
If only I had seen it sooner, at home! If only I had noticed it fall out of the push-chair! Oh, Woe that this should ever be – I had betrayed my very first Privet Hawk, and a lady too! Alas, her sex was all too evident, the ample abdomen having been ruptured, revealing its rich store of beautiful green eggs, already in place to provide future generations.
I told the agitated women it was only a moth, quite harmless, and I would take it away, which I did. I did not tell them it was mine; or they might have beaten me with their umbrellas for frightening them
The rest of it was pretty straightforward. By the early spring, the compost was quite dry, so I dug the remaining pupae out. There should have been eleven, but a couple had rotted & I think a couple more had tried to pupate in the same place, silly things. But the seven or eight left, were placed on corrugated cardboard in the bottom of a net cage, with twigs for wing expansion. Occasionally I would very lightly spray them with water. In due course, all emerged. Jars with water and privet twigs were provided, and every evening at dusk, they would warm up for flight.
The loud whirring of many wings, the surprisingly strong draught of air that came through the mesh of the cage was amazing - spellbinding. These were noble creatures, destined to fly fast in dead straight lines through the air, not sit in a cage. They had to be released, even though it was a bit early in the season for them. The decision was precipitated by the appearance of eggs on the privet leaves, and indeed on the gauze. Off they went.
I think I once saw a large hawk moth flying. It passed overhead in late dusk. It was just a dark spot, but it went as though it had been shot from a gun, dead straight, at high speed, and was certainly not a bird, let alone a bat. It was like a black shooting star, and must have been doing nearer 30 miles an hour than 20. It can only have been a Privet Hawk or a Convolvulus Hawk, or one of the other super-fliers, seriously bent on business of its own, definitely of no concern to us mere humans!
That’s it for Privet Hawks actually, except for one remarkable thing. The brood of eggs hatched, and at first the many tiny larvae could be accommodated on privet twigs in a jam jar. But for trivial (domestic) reasons which need not be explained, we ended up with only one pupa. That duly emerged the next year, and was put in the same cage, with a jar of privet so that it would feel at home. Imagine my astonishment, when after a week or two, eggs appeared, and duly hatched. Has there ever been a recorded case of parthenogenesis in Sphinx ligustri? I couldn’t work it out at all! Perhaps you can… Unfortunately, I no longer have the note-book I kept at the time. Not that that would explain the phenomenon, but it would at least give a few dates.
§4. The Death’s Head Hawk Moth – Acherontia atropos.
Growing children demanded more time, and amateur entomology receded; but one last grand effort was made, with the discovery of a source of eggs of the Death’s Head, the hatchlings of which, it was averred, would feed on privet. Rather than potato. And certainly rather than Jasmine, which was of course, the original food-plant of the Death’s Head, way back before potatoes were brought to Europe from the New World, several hundred years ago. Up until then, it was, appropriately, known as the Jasmine Hawk Moth. Ten eggs were obtained, but AFAIR, only four larvae grew to their immense size, as is their wont. I can’t remember what happened to the others. By this time, I suppose the mid-1980s, the idea of turning large full-fed larvae into buckets of compost had been abandoned, and everybody carefully saved their 250g plastic margarine * containers for their large larvae. All you did, was crumple up some absorbent paper, and put the larva and the paper in such a container, put the lid on and deposit it in a suitable (dark) environment, and leave the rest to the imperatives of Nature.
This was done, and the four containers were placed in a small cabinet in the living room, and forgotten about. Actually, it might have been better had they been put somewhere on the cool side – but, as it turned out, it didn’t matter, probably because I was often out working long hours, and the house was extremely draughty and cold anyway.
One evening some months later, I was reading a book, when I heard a scratching sound. Like a ‘mouse behind the wainscot’, to quote from Victorian Gothic novels. (Not entirely inappropriate, the house having been built in 1877). What could it be? It was coming from over there, on the other side of the room. It got louder as we went there. It was coming from the small cabinet on the sideboard. Of course: it was the Death’s Heads! We had forgotten them. The first one to emerge was scratching urgently, in order to escape from the plastic box, as well it might; after all, it had been expecting its pupal cavity to be made of earth, not some unknown substance that stubbornly resisted the onslaught of its claws.
Now, by happy chance, we had, not long before, made an incubator for home-made ginger beer. If you have read anywhere else in this unbelievably tedious website, you cannot have failed to observe that we get many fads & crazes, and like to tinker, to test things out. Ginger beer was a recent one, but a failure. We had put the bottles in a glass-fronted box, heated by a 40 Watt light bulb, controlled by a thermostat. Alas, all had blown the corks or stoppers out some time before, making a dreadful mess, which had been cleaned up, but the box remained, and would provide an excellent moth-house for our Atropos!
Hastily, sticks were procured from the garden and arranged so that the emergent moths could climb up and expand their wings. The first one, when the margarine tub was placed in the box and the lid removed, wasted no time. It did not stand on its dignity, fixing me with a baleful gaze; it simply took in its new surroundings post-haste, and scrambled out of the tub, walked purposefully to the nearest stick, and climbed up it.
Over the next day or so, the remaining three emergees did exactly the same. (The computer denies my word ‘emergees’, underlining it in red, but I will not be dictated to by a metal box. Unless it can synthesise, for example, diamonds; which so far, it shows no sign of doing.)
I tried to feed the Death’s Heads in the prescribed manner – i.e. drawing out their relatively short proboscis with a pin, into dilute honey, but had little success. Also, my children, who were at that time quite young, had mixed feelings about these magnificent insects. As I did not wish to mentally scar them for life (my children I mean, you silly!), I decided that the moths would be set free, even though it was far too early in the year.
How they went! They were not in the habit of ‘warming up’ at dusk, like the Privet Hawks; but once I took them outside, they quickly got the idea. The first one whirred increasingly, spun around on the ground a few times, then – zing! Up it went, straight as a die, at an angle of about 60°, as if it were flying up a taut wire. It was out of sight in about a second. This was marvellous. How did it know the angle to take? It was an old fashioned narrow back yard, and the egress was quite limited. I thought it might fly around & hover a bit, to orientate itself. Not a bit of it! Zip – and gone. Nature is not to be trifled with; but I was glad to have hosted those wonderfully developed & specialised insects.
* ‘Plastic Margarine’. An excellent, if inadvertent, combination of words! Margarine is a substance that has been foisted upon us for far too long.
26th November 2015.