Vladimir Nabokov and Butterflies

Many famous people have loved butterflies but this devotion has often been overlooked. Winston Churchill is one such person.  Churchill was in some ways a very unlikely Lepidopterist. Churchill was a soldier who fought on four continents. He was one of the only British prime ministers to have killed a man in battle ( Johnson 2015). He spent time as a prisoner of war in South Africa, was a journalist, politician, writer and war leader. Yet he found time for butterflies.

He planned to release large numbers of Black-veined Whites in the grounds of his home, Chartwell, Kent to try to reintroduce the species-it disappeared from England in 1922 for a reason or reasons that are unclear but that may be related to habitat change and poor weather.  Churchill’s plan ended in farce when his gardener removed the muslin bags containing the caterpillars from the hawthorn hedges and burned them instead of opening them. Now, thanks to a warming climate, Butterfly Conservation UK are planning to reintroduce the species from Northern France.

Churchill’s interest dated from childhood. When he was six, he wrote to his mother, Lady Jennie Churchill: “I am never at a loss to do anything while I am in the country for I shall be occupied with ‘butterflying’ all day (as I was last year).” This was just as well; his father was very distant (he also died young, at 45) and his mother was busy.

Some people ‘find’ butterflies at a time of great tension in their lives. The Liverpool writer of Irish descent,  Michael McCarthy, writes very movingly in his intriguing 2015 memoir, “The Moth Snowstorm” of how he came to discover butterflies in August 1954, just as Churchill was in his final, and rather decrepit state as prime minister.  Aged just 7, his family was in crisis. His mother, Norah, 40, was committed to an asylum and his father, a seaman, was frequently absent. His aunt Mary sold their Birkenhead house (!) and took the Michael and his very distressed brother, John, then aged 8, to live in Bebington,  a much greener location than their Birkenhead terrace. A nearby Buddleia was covered in butterflies. In the midst of the terrible suffering of his extremely distressed brother and confined mother, Michael gazed each day in wonder at the living jewels whose colours caressed his eyes and heart. Those Red Admirals, Painted Ladies, Peacocks and Small Tortoiseshells, whose glorious reds, blacks, maroon, purple, blues, salmon pink, white and orange on the purple Buddleia blooms had the young Michael enthralled. So began a life in love with nature.

In Europe (and later in America) the Russian writer, Vladimir Nabakov 1899-1977 combined his literary work with his study of butterflies. While justly famous for his literary work, especially for the disturbing novel Lolita, Nabakov pursued his scientific work with great diligence. His ideas on butterfly migration have recently been taken more seriously. In 2011 it was confirmed that his 1945 theory that Polyommatus blues (a genus of blue butterflies including Polyommatus icarus, the Common Blue, found in Ireland) had colonised the Americas from Asia in a series of waves across Beringia (the Bering Strait and adjacent parts of Siberia and Alaska) was proved correct.

Dr Naomi Pierce, a co-author of the report (Phylogeny and palaeoecology of Polyommatus blue butterflies show Beringia was a climate-regulated gateway to the New World), organized four separate trips to the Andes to collect the blues, and then she and her colleagues at Harvard sequenced the genes of the butterflies, as well as comparing the number of mutations each species had acquired. Their research resulted in the revelation that five waves of butterflies came from Asia to America, as Nabokov had originally hypothesized.  The report can be found here: https://royalsocietypublishing.org/doi/full/10.1098/rspb.2010.2213

Nabokov based his original idea of the origins of the Polyomattus blues in the Americas on morphology, especially on male genitalia. His views, in the words of the report, “were uncannily correct in delineating not only species relationships but also the historical ordering of these five key (colonisation) events in the evolution of New World blues.”

Nabokov also worked as a taxonomist, placing species in genus and families and even describing new species.  Many Lepidopterists regarded Nabokov with some disdain seeing him as a reasonable describer of butterflies but lacking important scientific insights.

In 1944, for example, Nabokov published the first description of the Karner Blue, a rare butterfly that lives in the northeastern United States. Judging from its colour and choice of foodplants, Nabokov came to believe that it was a distinct species. But when scientists began to analyze its genes, they decided it was just part of an existing species, the Melissa Blue Lycaeides melissa.

However, a study published in 2010 (https://royalsocietypublishing.org/doi/full/10.1098/rsbl.2010.1077) revealed that Nabokov was right.  The study found that gene flow between the Karner Blue and Melissa Blue is low, and comparable to the gene flow between L. melissa and another species, L. idas. Considering this population-genetic evidence, the study concluded that the Karner Blue is a unique evolutionary lineage that should be recognized as Lycaeides samuelis. This matters greatly because not only does it clarify the taxonomic status of the Karner Blue, it also adds urgency to the need to protect the species. This butterfly has suffered because the butterfly’s only known larval foodplant, Lupinus perennis, (a beautiful member of Fabaceae, the pea family)  which occurs in habitats such as pine barrens and oak savanna are being impacted by fire suppression work.

Perhaps more of Nabokov’s impressive work will now be reassessed and confirmed using next-generation genetic sequencing. The work by the scientists in the two studies mentioned here shows that examination of the wing characters, colouring and genitalia undertaken by Nabokov can be a valid way to assess butterfly origins and taxonomic status.

Nabokov’s devotion to butterflies continued to his last days. As he lay dying in July 1977, he remarked to his son Dimitri that a certain butterfly would soon be on the wing. Vladimir, it seemed,  knew that he would not live to see it. But he left a rich legacy of scientific discovery and knowledge as well as his literary work, a life enjoyed and well-lived.

Polyommatus icarus, the Common Blue. Photo J.Harding.

 

 

Warmer weather to tempt butterflies to emerge

Warmer weather forecast for the coming week should see spring butterflies-Speckled Woods, Orange-tips, Green-veined Whites and Holly Blues to take to the warmer, bluer skies.

All of these butterflies will fly along sunny, hedges with native trees and flowers, so a stroll abroad along sunlit hedges bordered by native flora and grasses should be taken. We want to know what you see, where you see it and the weather conditions. So, I will check a lovely sheltered lane within a kilometre of my home tomorrow or when we get the first sunny day. If I see a butterfly, it will be recorded like this and posted on the Records page 2020:

Jesmond Harding (06/04/2020)

Orange-tip 2, Speckled Wood 1 at N 91526 42532, Mulhussey, Co. Meath. Sunny, 14C.

I get my grid reference readings from https://irish.gridreferencefinder.com/.

Send your record to us at conservation.butterfly@gmail.com

I gave a talk to a very keen gardening group about enhancing their gardens for butterflies. When I showed a photograph of a male Orange-tip, their enthusiasm soared. All of the gardeners said that they had never seen one. But the countryside on their doorstep was awash with suitable habitat. It will amaze you-but you need to go out and look for him. Once you see one Orange-tip, you will always remember what he looks like.

This gorgeous butterfly rarely sits still but I guarantee that you will be impressed!

Please do observe physical distancing when outside. Take care.

Orange-tip on the Dandelion, a favourite nectar plant.©J.Harding.
The Orange-tip underside, on Dandelion. ©J.Harding.

 

Butterfly of the Year

In the following article, Butterfly Conservation Ireland’s Pat Bell looks back at his butterfly experiences over the past few years. These experiences can stay with us, adding great character to our memories, especially now while we have so much time to reflect.

I got the idea of picking a Butterfly of the Year a few years ago when reading Matthew Oates’s ‘In Pursuit of Butterflies’. His criterion is “the butterfly species by which the individual year is best remembered”. I find that in my case for some years this is a single sighting, event or place that is embedded in my memory while for other years it might be simply down to numbers. So here goes …

2009

It was September 2009 and I was surrounded by Painted Lady butterflies. They were rising up from a large patch of thistles growing on the banks of the River Rye at Louisa Bridge, Leixlip, Co Kildare. I had seen them already that summer both in my garden for the first time and in Altamont Gardens in Carlow. However, this was on a different scale and a unique experience. In hindsight, we now know that 2009 was an exceptional Painted Lady year in Ireland and most of Western Europe.

Painted Lady 2009.

2010

In 2010 I recorded the Holly Blue in my garden for the first time. I don’t know if I had missed it before but it is a species that fluctuates due to parasitism and it used to be mainly a butterfly of hedgerows but has been steadily expanding into gardens. I look forward every year now to the first glimpse of it and then to its second generation. I have seen it laying on holly blossom in my garden but it was high up and I couldn’t spot the eggs afterwards.

Holly Blue 2010.

2011

I started recording on the Royal Canal near my house for the Irish Butterfly Monitoring Scheme in 2011. My transect is the lovely stretch of canal from the harbour in Maynooth to Pike Bridge at the main entrance to Carton House. To my great surprise and joy, the most abundant species was the Common Blue. Sadly, this colony virtually disappeared in subsequent years, barely hanging on until making a big recovery in 2018 which it maintained, although not at the same level, in 2019.

Common Blue 2011.

2012

The Small Tortoiseshell was undoubtedly the star turn of 2012 and I wrote about this in my post of 24th March (https://butterflyconservation.ie/wp/2020/03/24/small-tortoiseshell-butterfly-in-the-garden-an-analysis-by-pat-bell/). In mid-September I had as many as 50 individuals on my autumn flowering buddleia which was some sight. Winner alright.

Small Tortoiseshell 2012.

2013

In 2013 it was a numbers game, specifically the Small White. It came out on top in all my yearly totals for garden, Royal Canal transect and especially my Stacumny transect with more than 300. These latter ones were especially prolific on the allotment section of that transect where of course there were plenty of their cabbage family larval food plants.

Small White 2013

2014

For many years I had enjoyed watching Red Admirals on my fig tree in late summer and early autumn. Overripe figs are especially soft and fleshy and I think it may be wasps that make the initial breakthrough. I also had a glut of plums in 2014 and lots of windfalls which I started putting out on the garden table and these proved to be a big hit with the Red Admirals and great entertainment for me.  A taste of this can be seen here: https://www.youtube.com/watch?v=07XV2FVNSjk

Red Admiral 2014.

2015

In early 2015 while recovering from an operation I did a bit of a desktop study tracking the expansion of the Comma out of its original Wexford stronghold. Andrew and Brian Power had done some great work in Carlow and along with Jesmond we wrote an item on this in Butterfly Conservation Ireland’s 2015 annual report. I started walking the Barrow north of Maganey Bridge that summer and was rewarded in August with the first recorded sighting of a Comma in Kildare – I’m claiming it anyway!

Comma 2015

2016

In the autumn of 2012 lots of Large White caterpillars were making their way to our allotment shed in Stacumny to pupate. However, they were virtually all parasitised and it was a grotesque sight to see these parasites emerging from caterpillars and pupae. This was happening everywhere apparently and led to a big collapse in their numbers so it gave me great pleasure to see a major recovery in all my counts in 2016. This is a very striking butterfly which shouldn’t be overlooked.

Large White 2016

2017

I experimented with a mark and release project with the Red Admirals in my garden in 2017. By chance, it happened to be a big year for them and I was kept very busy. I caught, numbered and released a total of 95 individuals which was more than I had expected but I was even more surprised that I recaught only two. There is a more detailed report on this in Butterfly Conservation Ireland’s 2017 annual report. (https://butterflyconservation.ie/wp/butterfly-conservation-ireland-annual-report-2017/)

Red Admiral 2017

2018

I rescued a colony of newly hatched Peacock larvae from a clump of nettles that was about to be cut on the allotment in mid-June 2017 and relocated them to the nettles in my garden. They thrived here and provided me with many hours of enjoyable close-up observations. The reward was record numbers of adult Peacocks in my garden in 2018 although it seems to have been a good year for them everywhere.

Peacock 2018

2019

The Comma had continued to expand its range, albeit intermittently, in the intervening years. Back in 2015, I had calculated its expansion rate to be an average of 10km per year at which rate it would be still a few years before they reached Maynooth. So I could hardly believe my eyes when two turned up in my garden at the end of August 2019 and hung around for a few weeks. One was quite territorial and they loved the fruit I put out for them (and the Red Admirals) more so than flowers. Oh yes, and I had amazing numbers of Painted Ladies as well – back to where we started!

Comma 2019

2020

This story waits to be experienced and written.

Perhaps you have a special reason to recall a year for its butterflies or have a special memory where a butterfly played a special part. Why not let us know?  Our Facebook page is waiting!

Pat Bell, April 2020

 

Cocooning

Cocooning is staying inside one’s home, insulated from perceived danger, instead of going out.

The fear and frustration being felt across the world by restrictions imposed to protect public health are extreme for many of us. Who doesn’t enjoy the freedom to gulp down draughts of fresh spring air, to enjoy physical movement, to hear the birds sing, bees hum and enjoy the visual accompaniments of the season?

Perhaps most accept the strictures are necessary however much we detest these limits. There is, of course, the prospect of freedom in the future, whenever that will be. That prospect will motivate some; just as lent ends and Easter arrives, just as winter is followed by spring, just as the night is succeeded by dawn, we will move away from this unwelcome, worrying and unhappy time.

Perhaps we should look at this enforced confinement as a time of growth, unseen, undetected but no less profound for that. We might see it as a time of delay needed for growth. We might see it as an interruption. In fact, we have examples of all three situations in the world of butterflies.

Growth Unseen

The clearest example of concealed development lies within the pupa. The ancient Greeks thought of the pupa as a shroud but the insect is undergoing dramatic and profound growth. Some of the development that transforms a caterpillar into a butterfly actually happens in the final stage of the larva but it is within the pupa that the powerful morphological alterations occur. Sometimes the pupa does not last long. It can last less than a week in some species in good weather but may last several months when the pupa is the over-wintering stage. Take an Orange-tip caterpillar that pupated in June-its pupa might last a full year or even two, if it over-winters twice, which can happen in this species-a mechanism (pupal diapause) to protect the species against a bad year.

The pupa is not pretty. It is not meant to be. It is meant to conceal the developing butterfly. To look at a pupa is, quite often to look at a wrinkled, aged-looking shrivelled being, a decayed leaf, a withered dropping, a fragment of bark. Yet when ready, the pupa hatches delivering what in many cases appears to be the purposeless splendour of a ravishing confection. A dazzling master of flight succeeds stillness and confinement.

The pupa, apparently lifeless, is where metamorphosis takes place. © J.Harding
Common Swallowtail, Qala, Gozo, an iconic, powerful and elegant butterfly.© J.Harding

Interruption

Sometimes an intervention occurs that interrupts our lives. In southern Europe, extreme summer heat makes life extremely difficult for some adult butterflies. Some can migrate and resume their lives elsewhere-the Painted Lady and Red Admiral can use this strategy. But not everyone has the flight muscles for this task.

One such butterfly is the Meadow Brown butterfly, which occurs throughout Europe, including Ireland. In the southern coastal regions of the Mediterranean and the Mediterranean Islands, it can get dangerously hot.  Foodplants are not in good condition for egg-laying and even if they are, venturing out in the heat can easily kill. Avoiding the heat is not easy for a butterfly that must remain active. The response of the Meadow Brown (and other species) is known as aestivation. It rests in the deepest shade it can find, usually in dense scrub or in woodland, waiting for summer’s heat to pass. During a period of extreme heat, the Meadow Brown will slip out for a quick sip of nectar in the morning but quickly returns to the shade.

This female Meadow Brown, above Calypso’s Cave on the island of Gozo, has just left shade to feed-it quickly retreated into dense shrubbery.© J.Harding

Delay

Sometimes there are circumstances when plans must be postponed.  Some species have the ability to enter a state known as diapause. This phenomenon can occur in all life stages; the stage in which it occurs is determined according to the species. Diapause helps the species deal with adverse conditions that will occur with the less suitable conditions that will take place with seasonal changes.  Diapause is controlled by brain hormones and is usually triggered by signals in the environment that foreshadow unfavourable conditions. Once diapause has begun, metabolic activity is suppressed even if conditions favourable for development continue. This period of diapause is characterised by altered or reduced behavioural activity. Diapause in the egg, larva and the pupa confers increased resistance to the dangers of extreme winter weather.

The Small Copper may produce a third generation in some autumns but under cooler temperatures and falling sunlight levels in dull, cloudy conditions in late summer and early autumn, the larvae enter a diapause state. They cease feeding, change colour and hide deep in vegetation until the diapause stage is terminated in spring.

This Small Copper caterpillar from County Meath is feeding on Common Sorrel but it is about to enter diapause. The pink marking disappears over the winter. J.Harding

However, in spring when conditions improve, diapause is terminated, larvae resume their pre-diapause colour and feed eagerly. In late spring and early summer, the adults fly. As you can see from the photo below, it’s worth waiting for.

A Small Copper, County Meath © J.Harding.

There may be different reasons for diapause occurring in the adult butterfly. The Brimstone butterflies hatch from their pupae in summer but they do not breed during the year of their birth but delay reproduction until the following spring when the larval foodplant is in the right condition.

As we can see, nature has its reasons for putting activity on hold. Nature has much to teach us. We have much to learn. With the excitement that arises from discovery, I hope there will always be more to learn.

Some Painted Lady Scientists by Pat Bell

In the introduction to my post of last week, Jesmond referred to scientific research into the Small Tortoiseshell. This set me thinking and I would hazard a guess that the Monarch of North America is the most researched butterfly in the world. However, we have our own much-studied butterfly in this part of the world and that is the Painted Lady. This remarkable migrant butterfly has intrigued scientists for centuries and is still the subject of much research.

The BBC devoted an entire programme to the Painted Lady in 2016 entitled “The Great Butterfly Adventure – Africa to Britain with the Painted Lady”. This gets reshown from time to time on BBC4 and may be accessible in other ways. There is a fascinating behind the scenes look at the Natural History Museum in London which has the largest collection of Painted Ladies in the world. The museum was originally built to house the vast collection of Dr Hans Sloane, a 17th-century Irish scientist and collector born in Co. Down, whose collection contains the oldest Painted Lady ever collected. This is preserved in a wonderful scrapbook put together by the Rev. Adam Buddle the botanist after whom the buddleia is named.

Constanti Stefanescu in Morocco

The star of this BBC programme is Dr Constanti Stefanescu of the Granollers Museum of Natural Sciences in Catalonia. He is the foremost expert in the world on the Painted Lady and we see him do everything from chasing around netting butterflies in Morocco to dissecting their larvae back in his lab for the purpose of studying their parasitic wasp. I was lucky enough to attend a presentation he gave in the Botanic Gardens in Dublin in October 2013, entitled ‘The incredible journey of the Painted Lady butterfly’, and subsequently exchange an email with him. He is well located as Catalonia is where the first generation touch down when they migrate northwards from Morocco towards the end of March. They don’t just refuel here, they produce a whole new generation. Although these adults will only live about three weeks they breed very quickly. The host plants on which they lay are primarily thistles and mallows but they can use a range of plants, unlike most butterflies, which likely contributes to their success.

Before I acquired a remarkable book ‘The Migration of Butterflies’ by C. B. Williams published in 1930, I was curious as to how much earlier scientists knew about this subject and how could they know? Williams had formerly been an entomologist with the East Africa Agricultural Research Station and at the time of publication was lecturing in Edinburgh University. In addition to his own observations and research, he corresponded with a wide network of scientists and naturalists all over the world long before the advent of computers, the internet or social media. I was surprised at the large number of butterfly references in scientific and entomological publications of 100 years ago and more and newspapers even reported on butterfly topics.

Interest in the subject had picked up in 1879 with the largest migration in Europe for a century when clouds of Painted Ladies ‘cast shadows on the ground’. There was much correspondence during 1879 on the subject of ‘butterfly swarms’. J. H. A. Jenner wrote to Nature in July “With reference to the swarms of butterflies referred to by M. Forel, in NATURE, vol. xx. P. 197, it may be interesting to mention that Vanessa cardui is this year very common in the south of England. This butterfly is known to all English lepidopterists to be ‘periodical’ –in some seasons it occurs in great numbers, in others—perhaps for several years in succession—not one specimen is to be seen.”

There was still some scepticism in the scientific community that insect migration occurred at all. Williams painstakingly accumulated the evidence from recorded observations including many of his own. Two of the key indicators looked for by Williams as evidence for migration are ‘observation of unidirectional flights’ and ‘periodic occurrence’. He logged records and constructed flight charts based on data he collected. He knew that Painted Ladies originated in North Africa and flew northwards, “crossing the Mediterranean with ease” and that they produced new generations in Europe. However, as evidence of return movement was not established, the general belief was that they died out at the onset of winter and we had to wait almost another century before this mystery was solved.

It was cracked at Rothamstead Research Centre in Hertfordshire using vertical-looking radar which detected that the Painted Ladies were flying at a height of over 1,000 metres. No other migrating insects fly at such a height and explains why their return flights are not seen. They calculated that 11 million butterflies arrived in Britain in the spring of 2009 but that 29 million started the journey south that autumn. Rothamstead is the world’s leading centre on insect science and we also see in the BBC documentary some of their other amazing research such as fixing tiny radio antennae to individual butterflies to study their flight patterns using tracking radar and research into how they use the sun to navigate.

Rothamstead research station’s vertical-looking radar

Irish scientists have also researched the Painted Lady. In February 2012 Dr Eugenie Regan, then with the National Biodiversity Data Centre, undertook a field trip to Morocco. Eugenie had collaborated with Constanti on some of his research and was following up on a field trip made by him a month earlier. The aims of the trip were to confirm known breeding sites identified by Constanti, collect larvae to analyse for parasitism and to search for possible new breeding sites. She had limited success with the first two objectives as it was possibly just past the peak pupation period but she had a notable success with the third objective. She found evidence of breeding in the Draa Valley in Southern Morocco on the edge of the Sahara and observed adult Painted Ladies flying in from the south thus raising the possibility that their range extends to sub-Saharan Africa. This has now been confirmed by subsequent studies and Constanti’s team analysed hydrogen isotopes in the wings of butterflies collected in tropical Africa which revealed that most of the autumnal Painted Ladies caught in sub-Saharan Africa had emerged in southern or central Europe and must, therefore, have undergone one of the longest migratory journeys recorded for any insect.

In July 2013 Eugenie and Dr Emily Gleeson of Met Éireann published a paper in the Irish Naturalists’ Journal entitled ‘The Painted Lady (Vanessa cardui L.) migration of 2009 as recorded by the Irish Butterfly Monitoring Scheme and an investigation into the origin of the migration’. The paper describes the Painted Lady migration of 2009 highlighting the large arrival at the end of May. Only a small proportion of these butterflies appear to have successfully reproduced that summer unlike in Britain. Weather data and back trajectories were used to investigate the origin of the May migration and these analyses showed that the butterflies probably travelled through France, England and/or Wales before arriving in Ireland. The next big Painted Lady year was 2019 and Jesmond has documented this in Butterfly Conservation Ireland’s 2019 annual report. The authors acknowledged the contribution of the network of citizen science recorders across Ireland.

Eugenie Regan searching for Painted Lady caterpillars in Morocco

There were many forerunners to the modern-day citizen scientist; amateur enthusiasts and naturalists who recorded, kept diaries and published. Some of these were in the far-flung corners of the British Empire as was Williams himself. Sydney B.J. Skertchly wrote to Nature in July 1879:

“Some, at least, of the swarms of V. cardui originate in Africa, one of which I witnessed a day’s march west of Sowakin, in Nubia [modern day Sudan], in March 1869. Our caravan had started for the coast, leaving the mountains shrouded in heavy clouds, soon after daybreak. At the foot of the high country is a stretch of wiry grass, beyond which lies the rainless desert as far as the sea. From my camel, I noticed that the whole mass of the grass seemed violently agitated, although there was no wind. On dismounting, I found that the motion was caused by the contortions of pupae of V. Cardui, which were so numerous that almost every blade of grass seemed to bear one. The effect of these wrigglings was most peculiar, as if each grass stem was shaken separately—as indeed was the case—instead of bending regularly before a breeze. I called the attention of the late J. K. Lord to the phenomenon, and we awaited the result. Presently the pupae began to burst, and the red fluid that escaped sprinkled the ground like a rain of blood. Myriads of butterflies limp and helpless crawled about. Presently the sun shone forth, and the insects began to dry their wings; and about half-an-hour after the birth of the first, the whole swarm rose as a dense cloud and flew away eastwards towards the sea. I do not know how long the swarm was, but it was certainly more than a mile, and its breadth exceeded a quarter of a mile.”

Your own observations can contribute to our knowledge of the Painted Lady. Your records to the Butterfly Conservation Ireland recording scheme is one way of doing this. See https://butterflyconservation.ie/wp/records/ Another way is participation in our garden survey, see https://butterflyconservation.ie/wp/wp-content/uploads/2017/12/National-Garden-Butterfly-Survey.pdf.

 

Pat Bell, March 2020

 

Butterfly Lore

There are some interesting stories arising from the activities of butterfly lovers from times past. Here are a few of them. We hope you enjoy them.

The greatest Irish poet, William Butler Yeats, 1865-1939 is a world-renowned literary colossus, but a little-known interest of his was natural history. Yeats was, as a child, obsessed with zoology and biology. He went on frequent entomological field trips and collected butterflies, moths and other insects. While his father encouraged his son’s passion, the young Yeats’s love of moths created concern. He liked being alone with nature and his poetic thoughts. He worried his father by sleeping at night among the rhododendrons and rocks in the wilder part of the grounds of Howth Castle. He was around 16 at this time!

Edwin Birchall 1819-1884 was born in Leeds but moved to Dublin for business reasons. He retired to the Isle of Man after he suffered an injury believed to have been sustained by a fall from a cliff at Howth.

One of the greatest mysteries of Irish Lepidoptera has much of its origin in Birchall’s claims. He made a very specific and detailed claim to have seen the Small Mountain Ringlet on Croagh Patrick Mountain. Many Lepidopterists have since searched the site (one of them a great many times) but found no sign of this rare mountain species which still exists in Scotland, Northern England and in mountain ranges in Europe. Some now doubt that he told the truth. Did he tell a lie? Unfortunately, dishonesty was quite prevalent in entomology at the time, especially when reputation and money were at stake.

A fairly roguish collector was Lord Clonbrock, County Galway. He reported several species ‘new’ to Ireland. His records were actually accepted and published. His gamekeeper ordered specimens from a dealer and Lord Clonbrock, who gave a guinea to his gamekeeper for each new discovery, intercepted a package containing a ‘new’ discovery/discovery. It appears that his lordship was implicated too, however!

Perhaps the most formidable collector was James William Tutt, 1858-1911. Tutt was born in Strood, Kent. Even at this remove, he appears to have been a fearsome character. He said it as he saw it. Tutt was often sarcastic and rude, which drove gentler souls away from entomological societies in order to avoid him. Tutt once said, “I know that I am brutal in the way I put things but I can’t help it, and you know I am right”. However, when he was wrong, he readily admitted it. An avid collector he published two large-scale works and contributed over 850 articles to entomological journals. A poorly-paid schoolmaster, he left 24 properties in his will. His great collection of moths and butterflies was unfortunately broken up and sold cheaply; this is seen as a significant loss. Tutt however observed industrial melanism in moths before scientists did but reached his conclusions based on guesswork. As he may have put it, “You know I’m right”.

One of the greats is Norfolk-born Frederick William Frohawk, 1861-1946. His love of butterflies dated from age seven when he netted a Pale Clouded Yellow: “I dropped on my knees and stealthily crept up on the butterfly and suddenly plopped the net over it, greatly to my intense joy. I instinctively seemed to realise the rarity of my capture”. Frohawk lived in a time when butterflies were very abundant, luckily for him. On his first visit to the New Forest in Hampshire in 1888, he wrote:

“Insects of all kinds literally swarmed. Butterflies were in profusion, the Silver-washed Fritillary were in hoards (that is certainly not true of the New Forest today) in every ride…as were both the Dark Green and High Brown Fritillaries…White Admiral were sailing about everywhere…Large Tortoiseshell was a frequent occurrence and the Brimstone abundant in every ride”

Sadly, the High Brown Fritillary is extinct in the forest while the Large Tortoiseshell is most likely extinct in Britain (neither of these was reliably recorded in Ireland).

Like many Lepidopterists, he was very energetic-he once (1884) walked 42 miles at night by moonlight. Perhaps his greatest contribution to our knowledge was his rearing from the egg every British butterfly. He illustrated each stage, including individual larval instars. He sometimes spent hours on end, staring at an egg, waiting for it to hatch, or intently observing a caterpillar to witness its moult. This work, which resulted in copious notes and 900 drawings, took Frohawk twenty-four years to complete.
Today a ride in the New Forest is named ‘Frohawk Ride’ where the Silver-washed Fritillary remains relatively abundant.

Hopefully, as a love for butterflies develops in Ireland, we shall have ‘native’ Lepidoptera legends to inspire a desire to study and protect our butterfly heritage. If such a figure emerges, what will our butterfly and moth populations look like then?

Silver-washed Fritillary, male.  This magnificent butterfly is now more widespread in Ireland that in Britain, where it has undergone a decline, but with a recent, modest increase. ©J.Harding.

Eyes, nose and mouth

Butterflies and moths appear to be simple creatures that flit about fitfully in the warm sunshine or mild, muggy nights, find food, mates, breed and expire, leaving behind their legacy of eggs to commence the next generation.

However, they live in a complex world so butterflies and moths are equipped with a range of equipment to navigate the challenges of life.

Here we will consider three-eyes, nose and mouth

Eyes

Butterflies and moths have two compound eyes on either side of the head. Each eye contains thousands of individual eyes or ommatidia, up to 17,000 in total, each one a working eye. These provide 360-degree vision. Each ommatidium contains a cornea and a cone.  These function as a lens.  Light travels down a rod behind its cone to reach sensory cells. In moths that fly at dawn and dusk the distance between the cones and sensors is greater than in day-flyers, increasing sensitivity.

It is likely that the short focal length of the ommatidia means that everything within 650 feet (200m) is highly defined. The butterfly/moth’s brain can detect light and darkness very effectively meaning that they can detect movement within its field of vision. This means that they can judge the closeness of a predator and take evading action.  This is why you need to approach a butterfly very carefully, slowly approaching for a closer view. Butterfly vision does not detect such careful movement efficiently or at all unless you darken the butterfly’s surroundings.

All-round vision is vital for a vulnerable butterfly. It allows the butterfly to probe the right part of a  flower for nectar while keeping watch on the approach of threats or mates.

It is not clear whether butterflies and moths can detect detailed patterns on each others’ wings to identify an individual of its own species. It may be the case that butterflies can only make this identification when they are very close to another butterfly. However, butterflies can see colour. This would explain why male Silver-washed Fritillary and Pearl-bordered Fritillary butterflies pursue orange butterflies-the females are orange on their upper surfaces as are males. Butterflies also see ultra-violet light-this may help ‘blue’ butterflies discern members of their own species, a vital ability in some grasslands on the continent of Europe where there may be a dozen blue species flying in the same area at the same time. Iridescent colours produced when sunlight refracts from the wings of their own species can be recognised.

Some butterflies do not seem to be able to recognise shapes; this results in females having difficulty in identifying larval foodplants-this is seen in the Wood White butterfly, Leptidea sinapis, which cannot distinguish by sight a larval foodplant such as Meadow Vetchling from a non-larval foodplant such as Bloody Cranesbill. Another result of being unable to distinguish shape is the tendency of the males to pursue as a potential mate any moving insect or even birds-male Dark Green Fritillary butterflies do this.

Nose

The organs of smell are the antennae, palpi and sensory cells on the thorax and legs. It is likely that each is used to ‘smell’ a different substance. The antennae are prominent stalks that emerge from between the eyes of butterflies and moths. In butterflies and some moths, these terminate in a club while many male moths have a feathered or pectinate (toothed like a comb) antennae.  In moths, these are covered with olfactory sensors used to detect the scent of pheromones released into the air by females awaiting copulation. This is especially striking in the male Emperor moth, a day-flyer who locates females by scent not sight. Butterfly antennae are also used to detect pheromones. Antennae are also used to find nectar-butterflies bend their antennae clubs towards an inflorescence, probably to determine which floret still holds the nectar.

Palpi look like a nose; this is a pair of parallel projections at the front of the head. These might also be used to detect food. These are very sensitive to touch; touch the palpi of a resting butterfly and it reacts immediately. This may be a warning system to warn it off harmful substances such as sticky tree sap.

Olfactory cells on the thorax and legs may be used to identify larval foodplants. Male Brimstones touch unleaved twigs in spring, probably seeking out larval foodplants to identify areas that females are likely to frequent. Female Common Blues drum on leaves, to identify larval foodplants. It is also likely that they are trying to detect concentrations of nutrients important for larval development so that she can lay her precious eggs on not just the right plant but also on the best part of the foodplant.

Mouth

Butterflies and moths have a proboscis. Some moths lack a proboscis and do not feed, relying on fats and proteins accumulated by their enormous larvae-the Oak Eggar is one example of a non-feeding adult. The proboscis is actually a hollow straw. But it is really a pair of c-section tubes, shaped like a rainwater gutter that is joined by hooks. When the adult butterfly hatches from its pupa, these tubes are unattached. The butterfly links these two parts before taking flight. When the butterfly hatches from the pupa, it may use the proboscis to suck in air to help inflate the wings. The adult can uncouple the proboscis using its legs in order to clean it to ensure that it does not become clogged. I have seen the Brimstone do this.

The main function of the proboscis is to feed by sucking up nectar, sweet secretions and mineral salts dissolved in damp mud and other, often less attractive substances!

The organs described above may have other functions not mentioned here. The antennae are certainly used for navigation; the base of the antennae contain the Johnston’s organ, used to orientate and balance the butterfly in flight. The clubs may play a role in navigation too; if a Speckled Wood loses both clubs it cannot navigate; is spins about in the air, totally ‘blind’.

With their range of sensors, linked to the brain, a moth and butterfly has all the necessary information needed to secure its survival.

Garden Tiger showing comb-like antennae. Photo Don Hodgers.
Brimstone, male, on bramble. Note the eyes, proboscis, dark red palpi and antennae. Photo © J. Harding.

 

Spring Scenes

Today we offer a photo post. All of these photographs were taken in the past week and offer a snapshot of spring. All photos by J.Harding

Coltsfoot, an early spring bloom. Driving to the west of Ireland, Irish poet Eavan Boland describes her car journey passing “splashes of Coltsfoot”.
Primrose, a common sight on natural, unsprayed hedge-banks. While not especially rich in nectar, it does feed butterflies. The Brimstone has been observed feeding on this flower.
Common Dandelion is one of the most important wildflowers for butterflies. The plant is unjustly hated. It is not a threat to health and a large range of bees and butterflies feed on the pollen and nectar while seed-eating songbirds flock to feed on its seed. Every wild garden must have this plant.
This Peacock was sunning itself on the towpath of the Royal Canal, Leixlip, County Kildare in the sunshine of last Thursday, March 26th.
An early Cowslip flower-it usually blossoms in April. It is closely related to the Primrose and natural hybrids, called False Oxlip is frequent in parts of the Burren, County Clare.
The humble Common Dog-violet’s tiny flowers appear in spring and this is the only time when the plant is in any way conspicuous. Small it is, but it is a vital foodplant for three of our fritillary butterflies, including our largest resident butterfly, the Silver-washed Fritillary. For William Wordsworth, the flower was conspicuous and obscure: A violet by a mossy stone/Half hidden from the eye!/Fair as a star, when only one/Is shining in the sky.
At last, frogs have laid spawn in my garden pond. Smooth Newts are insatiable feeders on frog tadpoles. I watched one last night attempting to chew through the jelly to eat the eggs. It did not succeed but when the jelly breaks down…
A female Smooth Newt from my garden pond. Newts spend most of the year on land, so the terrestrial habitat that surrounds the breeding pond is important. A mature garden with plenty of invertebrates with a place to conceal itself during winter, such as a large, flat stone a large log or a paving slab usually in a cool situation, will help it. Many farmland ponds have been lost but this amphibian is quite happy in a garden pond.

The Lady who loveth butter-flies

In 1658 the word ‘butterfly’ in its modern English form appeared in the work of Thomas Moffet (1553-1604) as translated into English in that year. At his time the renaissance spirit infused Elizabethan England causing some to look at the natural world with a great deal more interest and curiosity than before. Go forward a half-century and onwards after Elizabeth II’s reign ended in 1603 and there were more gentlemen collecting and studying butterflies.  These included John Ray 1627-1705, Joseph Dandridge 1664-1746, James Petiver 1663-1718 and William Vernon 1660-c.1735.

However, only one of the Lepidoptera pioneers had a butterfly named after him, or to be correct, her.

Eleanor Glanville was born in Yorkshire in about 1654, the daughter of Richard and Muriel Goodricke, the cultivators of the Ribston Pippin apple. From her parents, Eleanor inherited considerable property, including Tickenham Court, Somerset, where she later lived.

Tickenham Court, Somerset. Photo Historic Houses Foundation

Eleanor’s interest in insects seems to have begun after the demise of her second marriage to Richard Glanville who once held a loaded pistol “to her breast” and threatened to shoot her dead.  Glanville wrote to other entomologists, such as Ray, Vernon, Dandridge among others. She sent cases of specimens to her correspondents among them a fritillary she caught in Lincolnshire in about 1702.  This specimen was used by the great Swedish scientist, Linnaeus to describe the insect for science. This was first called the Lincolnshire Fritillary.

Eleanor reared butterflies and moths,  including Green-veined White and High Brown Fritillary.  She collected caterpillars from hedging by placing a sheet under the hedge and beating the shrubbery with a long pole, much to the amazement of a witness, John Brewton, who described how Eleanor and two girls performed the operation to “catch a parcel of worms”. Eleanor did not seem to know how to protect her collection; mites did much damage. However, three of her specimens, a butterfly and two moths, have been re-found in the Sloane Collection in the Naural History Museum, London. (Hans Sloane, 16 April 1660 – 11 January 1753 was born in the charming village of Killyleagh, County Down where a statue commemorating him stands. From an Ulster-Scots family, Sloane donated 71,000 items he collected to Britain).

The turbulent private life of Eleanor Glanville was reflected in what happened after she died. Sadly, her interest in butterflies was used to damage her reputation. Her estranged husband, eager to get her property, planned to kidnap one of her sons and persuade the boy to transfer his interest in the property to him and his new mistress.  Aware of her husband’s plot, Eleanor arranged to leave her property in the care of trustees.  She left her property mainly to Sir Henry Goodricke, her second cousin.

However, her will was challenged by Eleanor’s eldest son, Forest.  He contended that the will be set aside on the grounds that his mother was insane and believed her children had been changed into fairies. That was advanced as the reason that she acted unnaturally in not leaving her property to her own children.

The evidence produced at Wells Assizes in 1712 involved 100 witnesses. Either Petiver or Sloane appeared as a character witness. Villagers testified for the plaintiff, describing Eleanor’s eccentric behaviour. The court found for the plaintiff, no one “not deprived of their senses should go in pursuit of Butterflyes”.  Her will was set aside. Eleanor Glanville was effectively declared insane.

There is a happy ending of sorts. By the time she had been dead forty years, the accepted name of the fritillary Eleanor discovered in Lincolnshire bore her name. It still does; the Glanville Fritillary.

Glanville Fritillary. Photo: Peter Eeles. Peter has written a superb book, The Life Cycles of British and Irish Butterflies. For details, see https://www.ukbutterflies.co.uk/index.php

 

 

Small Tortoiseshell and the lost Generation

The Small Tortoiseshell is probably one of the most-loved butterflies in its vast European and Asiatic range. Apart from its beautiful patterning and colouring,  it seems to like us, endearing us to it. The butterfly likes to visit our gardens,  likes the flowers we plant, is quite tame allowing us to take a snap, the caterpillars eat nettles, helping to control this plant. And to top it off, they’ll even move in for the winter without causing us the slightest trouble. In fact, our guest stirs our desires to care for nature, a very positive feeling we can all do with. We admire the butterfly’s fortitude and staying power, going months without a sip of nourishment only to surge into the spring sunshine. What’s not to like about the Small Tortoiseshell?

And it is with us as an adult for almost the whole year. It is admittedly scarcer in June and in some years during mid-August when it is mainly found in the immature stages but this gap is short. It flies in the open from March-May and July and August-October.

The butterfly can produce a number of generations in a year. In colder parts of its range, such as Lapland, and at high altitudes it produces just one brood (univoltine) but, in warmer localities, it can fit in three generations (trivoltine). In Ireland, it is mainly double-brooded (bivoltine) but there are years when a small third generation is produced. The butterfly typically breeds in May/June and July when the gregarious larvae are found in warm nettle beds. In some years, larvae are found in September, the third generation.

From observations made in Ireland, the following brood structure appears to exist: a full first brood flying from late June throughout much of July (this generation results from the previous year’s butterflies that over-wintered). A second brood flies in August and some of September before entering hibernation. A small third brood flies in late September and in October which also enters hibernation. However, a small number of first-generation butterflies, which hatch from their pupae in June/July appear not to breed the year they emerge. These feed up for a few weeks in July and early August before entering hibernation. This brood pattern will vary according to weather conditions in a particular year.  Latitude does not appear to influence brood structure in Ireland-there is evidence from Donegal that there are two generations in the majority of years and a third flight in the warmest years in the south of the county (Aldwell and Smyth 2016).

Lost Generation

However, a study carried out in Hertfordshire, the county adjoining and north of London, may foreshadow what might occur here in future.  The study carried out in a shed in St Albans, monitored the dates that Peacock and Small Tortoiseshell entered and left hibernation in 2016, 2017 and 2018 with the figures for butterflies seen in flight over two periods, 2000-2009 and 2016-2018 (https://butterfly-conservation.org/news-and-blog/small-tortoiseshell-the-lost-generation).

The results are extremely interesting and highlight the butterfly’s adaptability.  But they might also foreshadow a less desirable development.

In 2017 all the Small Tortoiseshells were hibernating by 7th July. In 2018 hibernation was complete by 5th August. But in 2016 the last five did not enter hibernation until mid-October.

The figures for butterflies seen in flight in 2017 and 2018 tally with the hibernation statistics;  there was little or no evidence of a second generation in 2017 and 2018.  But there was a very obvious second brood in 2016.

What’s Happening?

I was in the south of England in the second half of July in 2018, when we had record-breaking high temperatures. I was visiting great sites for butterflies and many species thrived. However, I saw almost no Small Tortoiseshells, which bewildered me.  On some of the highest-quality reserves, I saw no Small Tortoiseshells but I did see Peacocks.

The summer weather in 2018, hot and dry, suited adult butterflies. There were plenty of nectar sources and warm weather to make it easy to move. However, the drought must have had a serious impact on larval foodplant quality and even availability. I do not know what triggers adult Small Tortoiseshells to breed or to hibernate but foodplant quality and or very warm, dry conditions might play a role. The ecological adaptability of this remarkable butterfly makes it a success but it is saddening to think that the butterfly may become much scarcer in our gardens in the future; it is the second generation that spends so much time in our gardens in August and September.

There is some indication that this switch to one brood is happening in Ireland. Frank Smyth (co-author with Robert Aldwell of The Butterflies of Donegal) has reported that the Small Tortoiseshell has been absent from Howth in a number of years from July until spring. According to Frank, this is a change in its occurrence in the area. This highlights the crucial importance of recording butterflies.

Is there anything we can do?

If we are to experience warmer, drier summers it is likely that the butterfly’s response, to abandon its second generation and enter the overwintering stage in summer will become the species’ new strategy.  Locally, there is some, admittedly limited scope for encouraging a second brood. When the first brood has pupated and the butterflies emerge, usually in late June/early July, cut the nettles and or water these heavily to encourage lush re-growth.  This should make the nettles available for breeding. A very important step is to provide plenty of nectar-if the adults need to drop their second brood, these will be busy feeding to build fat reserves for winter. Because of the very long over-wintering period, it is really important that the butterflies find the nectar they need.

Finally, keep the shed door or window open during a hot, dry summer. And keep spider webs to a minimum. Your butterflies need such sites and may need to call on your hospitality for longer.

Small Tortoiseshell.©J.Harding.