It wasn’t that long ago when seeing a butterfly was enough. There it is – that was nice! Then crack on. But now? It’s all about advancing the public archive. Smartphones materialise in some performative act of connecting to ‘The Nature’. Fine. And yet, I can’t help but wonder whether it’s because the natural world plays such a minor role in modern life, and encountering it is suddenly a novelty that must be immediately documented and preserved. Thou shalt seek the path with the best view and record crucial evidence of doing so. I was cycling through a park near home in Exeter when a runner made a concerted effort to stop, flamboyantly tapping a watch on her wrist. She quickly photographed a swan as it preened beside a patch of graffiti, which asked onlookers, ‘wHAt DoES yOUR SoUL LOok liKe?’ I smiled. I would have done the same.
Many people in the park were exercising with great determination. Faces wore hardboiled but jubilant expressions, as though the rush of endorphins and Lycra-assisted lunges were collectively giving Covid-19 the finger. I was on my bike and nodded to some other cyclists I passed on the path, the token fist bump of, ‘I see you (but only if I like your bike).’ It was June 2020, and the first lockdown due to the pandemic still blanketed the UK. But thankfully, the restrictions in place still enabled me to head out on my bike to try and see a butterfly – a childish-dream-turned-liberating-novelty, when so many people remained cocooned within an anxious chrysalis.
I was late, spinning past blocks of university accommodation and enjoying being out on my bike again. Like most people in their mid-20s, I lead a chaotic existence. A bit anxious. Pretty selfish. Back home after studying, daunted by debt, deciding what to do next. Blah, blah. (Quite pretentious, too.) That day, however, I was investigating. Nervous at fleeing the sanitised safety of home, my survey started small – cycling to Exeter St Davids station to board a train to Bodmin, Cornwall. Woodpigeons played maverick in the warm sunshine. As I sped along, shards of sunlight escaped through full, verdant branches in those stressful rhythmic strobes that pervade the kind of nightclubs I went to once or twice. Peering over Exeter’s Millennium Bridge, I spied another swan, a mother, serenely coiled on a raft nest. The father (as always with swans) was floating nearby, alongside a Lucozade bottle.
I arrived at the station in my latest incarnation as Hopeful Butterfly Whisperer. As I fumbled with hand sanitiser and tickets, the tannoy woman repeatedly thanked everyone for ‘maintaining a safe distance from other passengers at all times’ and ‘keeping travel to an absolute minimum’.
This passive-aggressive ‘absolute’ was personally directed at me. I was sure of it. Sheepish, I crouched, head hidden in my rucksack, conscience itching. Was going to see a butterfly via this ‘low-carbon route’ really necessary? My bike fell onto my shoulder like a provoking kick from a sibling under the table. The sun blazed overhead. A magpie spluttered into gear by the taxi rank, its plumage wickedly metallic as it stabbed a crisp wrapper with its bill. A robin assumed position atop the pillar box in a very ‘shut-up-I-am-very-busy-and-important!’ manner. Actually, I needed this. It was necessary, thanks.
Pulling away from the station, we began along my favourite stretch of track on the South Devon Main Line. After moving from America in 1998, our home for the following two years (a tiny riverside apartment) overlooked this huge stretch of the Exe Estuary. I still cannot believe our luck in kicking off childhood like this. I used to watch the caterpillar of train carriages from the lounge window as they traced the edge of my little world, like a giant game of Snake. I was four years old. Where was it going? Who was travelling? Why? Sometimes, if the tide was out, the carriage lights would reflect in the mudflats.
Twenty-one years on, and I was a passenger on that train, winding west. Individual trees, dips and rises of the land were as familiar to me as my own freckles. The tide was in, and a grey heron paused on the edge of a flooded pool as though testing the water’s temperature. Beyond Dawlish especially, window-seated passengers have the illusion of flying over the sea, so close do the tracks run along the sea wall. I’m pleased to admit that I’ve got a lot of time for the River Exe and its bottomless pit of nostalgia. I will never have enough of it.
Safe to say that after weeks of lockdown, the train was particularly thrilling. It felt criminal to be out. I had escaped and was on the run. Tannoy woman was no doubt raging on the platform back in Exeter, but there was nothing she could do now.
My favourite mode of transport, a striking white, red and black gravel bike, was wedged loyally next to me in the bike rack. I kept stealing glances at it like we fancied each other. We were set to have quite the year together. Through the window near Teignmouth, the sea looked soft and lumpy like an unmade bed. I wanted to sit in it. An idle column of iconic red sandstone braced the swell. Picking up more escapees in Totnes and Ivybridge, rivers turned to fields, flirted with moors and returned to fields. We sped through tunnels, and masked reflections peered back at us from black windows – our new selves. I studied my face as though it belonged to someone else.
Before I left home, a lady called Jo Poland from the Cornwall branch of Butterfly Conservation told me about an area of Bodmin Moor favoured by one of the UK’s rarest insects – the marsh fritillary butterfly, also known as Euphydryas aurinia. As you’ll find out, the marsh fritillary is a gorgeous little thing. But it doesn’t exactly help itself. Its penchant for moist and tussocky landscapes has largely confined it to western areas of the UK in erratic numbers, where this habitat is precariously holding on following a problematic agricultural past (hold that thought …).
Thriving in groups of highly connected colonies that radiate across highly connected habitats, the marsh fritillary generally sticks to flight distances of not much more than 50–100 metres – and lives the definition of a ‘social butterfly’. Hard and fast promiscuity within this insect’s environment is the nexus of its survival. Good quality connected habitat is the name of the game – the Union to the Jack. That said, it’s a butterfly that is both nowhere and everywhere. Although local populations remain so, as a species, it has curated a lifestyle to suit the climes of 38 countries in Western Europe, North Africa, Asia and Korea. The marsh fritillary strikes me as a cultured cosmopolitan.
Nearing Plymouth, queues of cars waited for green lights, like cows ready to be milked. Houses. More houses. Grey upon grey. From our vantage point crossing the Tamar Bridge into Cornwall, I watched as small boats and cars moved slowly towards the estuary mouth, like accessories to a giant train set. The thing about Bodmin Moor is that it’s one of those places that is very easy to overlook. Most people on their beeline to Cornwall simply whizz through Bodmin with a wee-stop and a picnic. (Me included.) But Bodmin deserves a lot more than that. A colourful history decorates this bleak, windswept land with Neolithic and Bronze Age hut circles, ruins of medieval chapels and the fabled resting place of Excalibur at the bottom of Dozmary Pool. Granite outcrops and stone circles sew a rich heath upland into an Area of Outstanding Natural Beauty, which is a bit of waffle for a habitat nearing the Top of the Aesthetic Class. Daphne du Maurier’s Jamaica Inn thriller was born here, as was the pub of the same name. The River Fowey rises high on the moor, just north-west of Cornwall’s tallest hill – Brown Willy, meaning, ‘Hill of Swallows’ (sure). Pulling into Bodmin Parkway station, I realised I had never been here before.
I set off along National Cycle Route 3 – a portion of the 328-mile cycle safari from Land’s End to Bristol, through Cornwall, Devon and Somerset. The National Cycle Network is identified by its blue signs, shining beacons of encouragement (or despair) for long-distance riders. In 1984, the Avon-hugging 15 miles linking Bristol and Bath on the disused railway was crowned as the first ‘route’ in the National Cycle Network. Now in the custody of the UK’s walking and cycling charity Sustrans, the network has grown to cover ten main national routes, ranging from the Shetland Isles to Dublin and St Austell, across 5,273 miles of engineless trails and 11,302 miles on some sort of road. Thankfully, my butterfly ride was just a wholesome 10 miles, and no fewer than three separate signs directed me and my bike to the trail.
Swooping under the rail bridge, I happened upon a dreamy scene straight out of Kenneth Grahame’s1 head. Petals had fallen from a vast magnolia. I flew down the pastel pink aisle, beckoned by the wedding of woodland arching over my helmet. When my Nanna died in 2002, the magnolias were in bloom. Now, every time I pass a magnolia with my mum, I know that she’s thinking of her. I think of her too. Further into this Wind in the Willows scene, a young rabbit inspected his front paw, and behind him, a Cornish vista unfurled. A greenfinch sounded like someone was trying to whistle and hum at the same time. Two ladybirds embraced on a nearby nettle. Good times. I was high up on the path over a bridge, and the River Fowey rushed below, too busy to stop. Perhaps this is what England once was. Provincial, spacious, deeply wooded – but not obsessively so. An enormous pastoral meadow percolated with oak, ash and beech introduced the sweeping grounds of the National Trust’s Lanhydrock Estate. The whole scene felt clichéd, strangely familiar. I liked it.
It is everything you might expect from a grand Victorian country estate. A lavish history of housing high-society mid-1600s Parliamentarians was enjoyed before a devastating fire in 1881. Later, its slate-and-granite walls sheltered evacuees and woodland ammunition stores during the Second World War (the surrounding deciduous canopy offered ideal protection from enemy eyes). And then, in 1953, the seventh Viscount Clifden – great, great uncle of Ollie Williams, Love Island contestant, winter 2020 – gave Lanhydrock House and 160 hectares of parkland to the National Trust. The plot thickens. As in early 2020, Ollie exclaimed to the press that he was the rightful heir to the estate before realising that once a property is nestled within the loving bosom of the National Trust and its members, ‘inheritance’ is no longer a thing. Another time, babes. Today, this Victorian estate is famed for its balance of being wealthy yet largely unpretentious. Not exactly, I thought, as I passed the seventeenth-century stone folly and gatehouse.
A raven clattered about in some branches overhead as though clearing up after a big meal. Heavy mouth-breathing seemed to help shift gears and pull me up a steep hill. In its Terry’s Chocolate Orange coat, a meadow brown butterfly flew with me as I drew Z-shapes up the hill. I still wonder whether it, too, was tracking our tango. At the top, I took off my leggings. Had to. The air felt impossibly thick, and I found myself standing, panting and trouser-less on the side of a Treffry Lane. For no reason at all, I ran across this Treffry Lane wearing just my pants – and ran back again. Perhaps in a confused bid to create some airflow and cool off? Hurriedly, I shimmied into cycling shorts and pretended that everything was fine.
Wending left on a satisfying hypotenuse across the estate, everything around me began to look very overdressed. Foxgloves adorned hedges like purple candelabras. The air smelled of festivals. Of Sundays and childhood. A carnival of spring colour with Free Entry! for all. Darting out from the right, a swallow conveniently flew down the next section of Route 3. A rubber-stamp approval from our most regal of migrants felt like a sure charm.
Beyond the hedge, I caught glimpses of where the butterfly was meant to be. High up on a hill to my left, the nature reserve emerged in a random blend of landscapes. Lying on the northern end of a granite ridge, Helman Tor is sandwiched within a celebrated area of conservation and history. One could say that it has done very well for itself, for it has quite the portfolio. The habitat surrounding the tor is one of the 57 nature reserves managed by Cornwall Wildlife Trust. Age has been kind to this area of land. It is now a County Geology Site (CGS), a Scheduled Ancient Monument (should we save the date?), and it lies adjacent to the Red Moor Site of Special Scientific Interest (SSSI) and Breney Common Special Area of Conservation (SAC). ‘Tin-streaming’ from open-cast mines sculpted the lay of this land for many years, including the setting of many of the ponds and woodlands, the scars of which can be easily seen and felt against the background hum of the nearby A30.
There’s more. Above a haze of foxgloves so numerous that the moor glowed fuchsia, buzzards cruised the thermals like a lazy river. I felt ushered towards a heap of granite that looked like a pile of laundry. Skidding to the side of the car park below Helman Tor, I addressed a serious state of hunger while sitting beside my bike under a tree, musing.
I considered that if I were on a similar nature escapade, say 30 years earlier, insects would have featured heavily. It’s one of those visions that people of my parents’ generation sometimes refer to: ‘We had butterflies everywhere!’ and ‘All over the windscreen’, ‘SPLAT! they’d go – every bloody time!’ And such. Thirty years ago in a given field, grasshoppers would have leapt ahead of me on my (ever so hearty) stroll. Midges and mayflies would have prompted the carefree hand-over-face waft – also typical. Fruit flies and other small things would have wriggled their way inside my clothes. Hoverflies may have occasionally taken a break on my shoulder. And I would have been OK with all of this. Perhaps I then would round a corner to discover a blossoming bramble bush, glittering with feeding meadow browns, speckled woods, red admirals, tortoiseshells and (while we’re in Utopia) all eight fritillaries. A riot of tiny life being lived.
Yet, I glimpsed into that old world as I sat there, failing to remember ever seeing so many butterflies and bees in one small space. Verges were humming. Not because of the A30, but rather an invertebrate full house. Or so it felt. A peacock butterfly sunbathed on a bare patch of ground. Red upperwings as rich as the season, its eyespots unblinking. Quivering in luminous flame, a brimstone butterfly fed on a pink ball of clover. Nature’s cosplay can be very convincing. I felt officially seduced. It turns out that this 500-acre (202-hectare) site is a veritable orgy of wet heathland, dry heathland, acid grassland, ponds, ancient oak and willow woodland – and loads of insects. Overall, it seemed I was experiencing a place where nature has been granted tenancy. That’s why it felt different.
Yes, other endangered species are available, some in even greater peril. But there was something about the marsh fritillary that pulled me closer, maybe because it’s considered a bit of a talisman across British moorlands. Or perhaps just because I liked the look of it. Either way, I was in.
Its UK distribution has declined by 75 per cent in 25 years (and the UK is still considered a stronghold). Sixty-six per cent of England’s colonies were lost between 1990 and 2000, and now it exists in a fugitive state amid a devastating loss of habitat. Unsurprisingly, this tip-toeing across a fraying tightrope has turned this insect into an international symbol of resilience, unwittingly catapulting it into big-picture conservation like a person who achieves overnight fame simply by surviving a horrible experience. A little dark, I think. Wildly intrusive. But for some reason, with the marsh fritillary, I’m left feeling impressed. As though its world is slowly descending to ashes, and yet, still it rises like the phoenix.
Such a rough ride in the UK and across Europe has made the marsh fritillary a conservation priority, which has afforded it the very highest levels of protection. A UK Priority Species, it has been fully protected under the Wildlife and Countryside Act since 1998, and it remains under ‘vulnerable’ European status. Why not throw in two international statutes of protection while we’re at it? All of which makes the marsh fritillary the most protected butterfly in the UK after the large copper and large blue.2 It’s safe to say that messing with this species will induce a legislative migraine.
It shouldn’t come as a shock to learn that agriculture has been the biggest threat to all butterflies in the British Isles so far. In the south-west of England alone, the annual turnover of agriculture is more than £2.7 billion – more than any other region. Bidding farewell to 92 per cent of regional culm grassland (tussocky, moist, generally fabulous) by merging fields and eradicating natural buffers over the past 100 years has removed a vital climate change ally from South West geography. Culm grassland stores five times more water than monoculture grassland – as well as filtering it, reducing downstream flood risk and improving water quality. There’s also the small bonus that the topsoil beneath the tussocks stores twice as much carbon as intensively managed farmland. And although 25 per cent of England’s SSSIs are in the south-west, nearly all of these sensitive areas (including Dartmoor and Exmoor National Park) are farmed.
Once widespread throughout the British Isles, the marsh fritillary has been an unfortunate passenger on some of the most nauseating population rollercoasters of any species. Colonies have been lost from 79 per cent of locations marsh fritillaries once were, and since the 1980s and 90s, the species was known to breed only on a handful of sites. Its history is a textbook tale of sacrifice and tyranny – apt bedtime reading. It’s also a story of what happens when we don’t employ landscape-scale thinking in our merry bid to armour a world against elemental surprise (while ensuring we get to live in a world that can also deliver hot ramen to our doorsteps with a mere swipe and a click).
The 2019 State of Nature report, published by the National Biodiversity Network, cited butterflies and moths among the hardest hit of all species in the UK. Humanity booms, wildlife dwindles. Alas. This tits-up of a trade-off will crop up quite regularly as you read this book – but there’s more to it. Since the start of the twentieth century, more than 77 per cent of UK land has been handed to agriculture and apparently improved (meaning a million hectares of wetland drainage, ploughing, reseeding, concreting rivers, having a literal field day with fertilisers … that sort of thing). And our bid to go all the way in our complicated relationship with carbon has removed nearly everything this butterfly needs from its ecosystem. So much so that in Devon and Cornwall, 8 per cent of the marsh fritillary’s favourite habitat remains, squeezed into two of Britain’s most popular tourist destinations. Both of these counties also happen to be gardened by a significant number of sheep, as you’ll find out soon.
First, though, permission to objectify this butterfly. Picture for a second, if you will, a Victoria’s Secret model on the runway – let’s go with Gisele. Gisele is glamorous. As far as we know, naturally so. A proper specimen. Dripping with allure, etc. And that’s what the marsh fritillary is – ahoy there! The undisputed cover star of the butterfly world. The name ‘fritillary’ is used for eight UK butterfly species, and stems from the Latin fritillus meaning ‘chessboard’, a title also bestowed upon the Heliconiinae butterfly family and Fritillaria flowers, the other chequered members of the natural world. Butterfly fritillaries are also collectively known as the ‘checkerspots’, which is just a delight anduch easier to remember. Put it this way, these dancing, brightly coloured miniature stained-glass windows make for a substantially more aspirational rendezvous than our reliable meadow browns (bless their tiny hearts).
The best way to tell that what you think is a fritillary is indeed a fritillary is to look at the underwing. These act as a trademark for each species. The creamy, apricot-coloured underwing of our marsh fritillary embodies the genre of colada we might sip on a harbour wall in Majorca while comparing tans and anticipating the night ahead. Its upperwings contrast vividly – bold and strong, perfectly traced in a soft black – the perfect outfit to complement the cocktail. To put it mildly, you are looking at the most satisfying aesthetic of symmetry and charisma. Marsh fritillaries are generally brighter and more outrageous than their seven cousins – their iconic sunset-and-black tessellation is made even more ‘haute couture’ by a row of tiny black dots skirting the edges of their hindwing. Like our own transition from sweet 10-year-olds into don’t-look-at-me-I-hate-everything teenagers, marsh fritillaries become shiny when their rainbow regalia fades. And in this state, they have been rather insultingly referred to as the ‘greasy fritillary’.
As far as I knew, I had never seen one before – despite my childhood featuring damp, delicious Bodmin and Dartmoor, both of which are good areas for them. Sitting below Helman Tor for some time, grass imprinted the backs of my legs. I scoffed some leftover mange tout from dinner the night before with immense disappointment. A beautiful second sandwich and an array of other snacks were forgotten on the kitchen table back home. An eager tick, climbing the laces on my left shoe, fancied some warm, recently fed mammal – it was one of many that have chosen me over the years. It struck me that I could lie there and await a long, slow peel into fatigue as I satisfy the sanguine urges of this tiny arachnid. It also struck me that I ran the risk of becoming a pathetic narcissist, and I had better bloody go and find what I came for. So, as I made a beeline for the sweet spot Jo Poland had described and, when not checking every available crevice for ticks, my eyes were primed for flashes of orange.
This species was becoming hard to resist. Every person I have spoken to about this butterfly, be it scientist, volunteer or general butterfly devotee – has raved about its life cycle. From a young age, the lullaby of the butterfly life story is drummed into us (or jolly well should be). The late Eric Carle created The Very Hungry Caterpillar to show our pre-school selves (and adults) the thrill of transformation. Sometimes, it’s the stories of the smallest beings that stay with us. Yet the marsh fritillary makes the typical egg-caterpillar-chrysalis-butterfly situation seem as dull as a Tuesday. Friends, this is a butterfly on steroids.
As Carle so beautifully wrote: all butterflies and moths have a four-stage, sequential life cycle: egg > caterpillar > chrysalis > winged adult. The marsh fritillary takes a year to waltz around that circle, and the caterpillar (larva) sheds its ‘coat’ five times – this process is ‘moulting’. Each stage between moults is called an ‘instar’ – and the marsh fritillary has six. OK, so far? Good. Marsh fritillaries have one annual flight in May and June, and I was hoping to catch the tail-end of this period. Their development is chivvied along by sunshine and warmth in a similar logic to a ripening banana on a windowsill: the warmer the site, the faster they develop. As soon as the adult butterfly emerges from the chrysalis (male usually first), mating is on the agenda – sometimes within the hour. After months of solitary infertility, their newly winged selves tumble into a flirtatious world of interpretive dance and promiscuity. Everything nature (and university freshers?) wished for.
A marsh fritillary couple is arrestingly beautiful. We may envy their lottery of perfect genetics but surrender to their appeal like a hysterical fan desperate for an autograph. You may be surprised to know that the mating ritual of a marsh fritillary is a prudent, ‘Don’t look at meh!’ affair. After a bit of impassioned zig-zagging, the male finds his equally eager lady. Pleasantries exchanged, the pair settle on a leaf perch and turn to face away from each other, joining only at the tips of their abdomens. These romantic rendezvous can, like any first date, last from minutes to hours. Next time you consider ‘multitasking’ as a problematic burden, it’s worth noting that some butterflies can casually fend off passing birds mid-coitus.
Nosy beaks aside, the male deposits his sperm packet – a neat dollop with a dash of nectar-derived carbs and proteins for good measure. This little sexual picnic seals the deal and fertilises the eggs that lie inside our patient lady, permeating through tiny pores in the eggshell. Now, the challenge is for the female to transport her immense cargo of (in some cases) 500 fertilised eggs to a leaf of Devil’s-bit scabious. Her abdomen is swollen and heavy, physically limiting how far she can fly. Eggs are always laid on the underside of the leaf, which generally needs to be large and cushioned to absorb the weight of hundreds of little life bundles.
For some people, this is a captivating moment. Dr Caroline Bulman, senior conservation manager for Butterfly Conservation and a leading authority on all things marsh and fritillary in the UK – is particularly taken with this part of its life cycle. ‘The number of eggs is truly staggering,’ Caroline smiled over Zoom. ‘Wander along grassland in May and June, find some Devil’s-bit scabious, turn the leaf, and you’ll see this gorgeous pile of newly laid yellow eggs.’
Being in late June, my visit didn’t yield any butter-yellow, perfectly spherical marsh fritillary eggs, which, when I looked them up, reminded me of miniaturised giant couscous. Each egg contains bundles of tiny cells, each cell primed to become wing scales, antennae or proboscis one day. With lives so entirely scripted, any butterfly we see demonstrates evolution at its most magnificent. At this point, the butter-yellow colour has darkened into a purply-brown, so the eggs now resemble giant couscous soaked in HP sauce. It takes around 30 days for their eggs to hatch, varying sometimes depending on whether early summer decides to be warm and sunny or wet and tragic. Once they hatch, the caterpillars emerge, and the silk webs are spun. Avengers, assemble.
I spent a happy hour wandering randomly all over the tor and enjoying the fact that it was Monday and I wasn’t doing Monday things. The sun was hot, yet the sky seemed to be having anger issues. Rumours of a thunderstorm murmured across the land. I am no botanist, but the plant life here was extraordinary. A real botanist would swiftly become overexcited, if you know what I mean – sundews, sphagnum, pillwort, Western bladderwort, forget-me-nots, birds-foot-trefoil, campion and endless grasses. I mean, come on. Half the time, I had no idea what plants I was looking at, which ones ran through my fingers or brushed my legs, but that didn’t matter.
The Devil’s-bit scabious is the eminent plant here. In mad, brilliant irreverence, it’s also known as ‘bobby bright buttons’ – a somewhat predictable move from botany (if we just revisit the plant names mentioned above …). Back in times of scabies and bubonic plague, Devil’s-bit was included in the treatment of skin sores – ‘scabious’ stems from the Latin word scabere or ‘to scratch’. Legend has it that the Devil bit off the plant’s roots in a fit of rage. Anyway, it was sadly not yet in flower when I was there (they usually flower from July). Still, I know it will become a pastel-purple, perfectly spherical jewel. Fitting, of course, for a flower so charming to be wedded to our marsh fritillary, as its larval food plant – the crucial piece in their puzzle. Put Devil’s-bit scabious and marsh fritillary together, and they are the power couple of moorland and mire, the equation that solves itself.
Like our marsh fritillary, this plant loves a damp meadow. It quite literally lives for it. It is also partial to a hedgerow, rocky grassland, calcareous grassland, mountain slope and stream bank, affording it a much healthier allotment across the UK. A member of the ‘teasel’ family, Devil’s-bit scabious famously drips in pollen and nectar. Even so, I believe it was its padded leaves and pincushion flower head that drew the marsh fritillary.
You may recall the joy of the childhood sleepover. The illogical thrill of spending the night on the floor, in a bag, eating different food at weird times and being told off by different parents. Of synching up sleeping bags right up to the top and worming around the room in hysterical shrieks. Well, oddly enough, butterflies do this – in their own way, of course – because a mass web of hundreds of caterpillars jostling for leafy floor space is the route to adulthood for the marsh fritillary. And if you’re interested, the Glanville fritillary also develops in this way.
Come July, the first instar hatch. The caterpillars are small and vulnerable, a blur of beige. They remind me of mini versions of retro Smith’s salt and vinegar Chipsticks spooned into the protective web of a sleeping bag that glues the leaves of the Devil’s-bit scabious together. An afterparty of larvae communing around a leafy table. The bundles of cells I mentioned earlier are fittingly called ‘imaginal discs’ and are delayed in realising their destiny by being regularly bathed in slurries of a juvenile hormone, which stops the caterpillar from growing up too fast. Think of it as working oppositely to testosterone in a 15-year-old boy suffering from the raging horn. In the teen boy’s case, a tide of hormones promotes maturation: terminal moods and hair erupting in unfortunate locations in their segue to manhood. Whereas in the butterfly, the hormones racing around the young larva’s body serve to stall that journey to adulthood – just for a while. Sure, the caterpillar eats, and its internal organs and surrounding muscles grow, but the imaginal discs keep it stunted for a bit. It remains a moving, eating, breathing embryo – pretty much through all six stages. Mildly disturbing, but we’ll go with it.
Instar two. The caterpillar matures. A ‘moulting’ hormone flushes through, triggering the shedding of its skin – yet the juvenile hormone continues to work to keep it a caterpillar. With independence creeping ever closer, instar two is less cul-de-sac sleepover and more ‘gap-yah’ hostel dorm. The caterpillars have darkened into a tan colour and busily spun a new web around the Devil’s-bit scabious, all the while feeding en masse in their foliate canteen. Another dose of the hormonal cocktail darkens the larvae into the third instar, as they busy themselves building an even denser, more concealed web of refuge to help them brave hibernation.
But before they brace for winter, they must moult into the fourth. The timing of this varies from early to late September, depending on the amount of sun and warmth on offer. Looks-wise, our soul-searching traveller has bid adieu! to adolescence as an ebony beauty. Jet-black spikes adorn its fourth self to deflect passing birds. The web acts as a kind of hammock. Although less conspicuous now, this silk web-caterpillar combo resembles a black hairball in the grass. Upon closer inspection, however, you’ll notice a black, writhing mass of caterpillars absorbing all available heat into late winter. They huddle like students in hats and hoodies at their desks, competing for the last of the hot water and fending off the heating bill.
‘It’s just astonishing’, remarked Caroline. ‘This tiny mass of two to three hundred caterpillars surviving through winter. While we’re all in our heated homes, they’ve had floods, frosts, snow, gales and all sorts hurled at them.’
When they’ve made it through the worst of winter, in swings instar number five. Creative differences have broken up the band, and now they forge their separate ways, eager to capitalise on their new solo careers. These caterpillars are still black and still drugged up with hormones, but now they’ve sexed up a notch and have white polka dots glittering across their bodies. Easy to spot in soggy vegetation, they’ve left their webs to focus seriously on their new roles as eating machines. Gorging many times their bodyweight in mulched Devil’s-bit scabious, it’s them against the world.
Caroline loves it. ‘You go out on those crisp, sunny spring days, and you find this tiny group of black clustered caterpillars basking in the weak sunshine, and you think – wow! There are marsh fritillaries, and they’ve survived through winter! When you really think about what they’ve gone through to get to this point …’
April heralds the arrival of the sixth and final instar, a now fully formed, mature, ambitious larva. Ready for some serious adulting. The white speckles are even more sensational. At this stage, we are reminded of the #basic biological urge that drives this unique succession of transition and growth in butterflies and moths. Fundamental, prosaic, innate. After five waves of two hormones at play, juvenile hormone relinquishes its grip on the imaginal discs, instructing them to grow into their specific body parts: the tip of a leg, the corner of a hindwing, the base of an antenna. A final surge of moulting hormone plunges the caterpillar into its white tiger-like chrysalis peppered with knobs and bristles. I’ll be honest – if you’re looking for magic in this world (aren’t we all?) you’ll find it in the soupy, embryonic world inside the chrysalis. Our beautiful ebony instar six is mostly recycled into the adult features of the butterfly, tessellating, meshing and conspiring under the canopy of its shell as the imaginal discs start to form a more coherent sentence.
Once the juvenile hormone has had its heyday of suppressing development and is all but disappeared, it’s time for metamorphosis. We have now waltzed a full circle and returned to our adult. Evolution’s prodigy. Ready to mate, disperse, lay eggs and live a private life. A Year on the Mire – the Lepidoptera3 soap opera on demand. Enchanté.
Right. Let’s talk timetables: colour codes, symbolic keys, meaningless subtitles – the lot. As we now know, the life cycle of butterflies and moths is so fastidious and regimented that unless everything happens in the correct order – and in the right place at the right time – it goes arse over tit. If you think you have an impressive five-year plan laid out to perfection, you’re about to be trumped. Egg-laying, plants flowering, leaves unfurling, leaves falling … my friend, nature has had a plan since the dawn of time. The study of all this is called ‘phenology’, but all you need to worry about is that more and more evidence shows that animals and plants are under pressure to change their ‘timetables’ in response to climatic stresses. Mismatches in food supply and demand alone would plunge me into a downward spiral of despair. And the thought of the marsh fritillary experiencing such malady leaves a bad taste in my mouth.
According to a few researchers in the Department of Zoology at the University of Oxford, plants and animals are likely to respond to ‘climate’ in three ways: by shifting their distribution to find ‘climate space’; by staying put and adapting ‘in situ’; or by adjusting their life cycles. Think of it as a shaky climate causing a jigsaw to misalign. Trying to stick to the plan nowadays is like starting the puzzle with all the middle pieces – a massive effort, and I imagine that species would rather not have to deal with all that admin.
The relationship between butterfly emergence and air temperature is a complicated one, for a good reason. Butterflies reflect the health of a habitat and, with their tight schedules and short generation period, they are sensitive to change – being among the first group of animals to show serious vulnerability to hidden foes like temperature variation. Extensive studies looking at butterfly collections since 1970 at the Natural History Museum found that for every one degree (Celsius) rise in spring temperatures, 92 per cent of the 51 species of butterfly studied responded by emerging one to nine days earlier. Case in point, the fine weather of spring 2020 saw the earliest average sightings of butterflies for the past 20 years. Perhaps you noticed?
‘There’s a common misconception about “this sunny weather” – that rain is for ducks and sunshine is for butterflies,’ said Caroline from Butterfly Conservation. ‘But we can’t afford to think like that any more – it’s so much more complex.’ True, and when you are fussy enough to rely on only one food source, and the nectar sources aren’t there when you dare to arrive early – you’re screwed, mate. We also need to talk about a wasp.
Around 80 per cent of butterfly species are prone to attacks by wasps and flies, in a concept known as ‘parasitism’. You may be pleased to know that these are not the wasps and flies you are already swatting away. No, these are a totally different genre. Attacks are a gruesome affair and the kind of bedtime story that would deter the average person from a smooth journey into sleep. For a parasitic insect, survival directly depends on the death of its host, following a slick: ‘hijack > eat > grow > escape > repeat’ programme.
Visits by certain wasps of the genus Cotesia are what plague our marsh fritillary, as these wasps have an exclusive appetite for its pretty caterpillars. Roughly three generations of Cotesia wasp are produced per generation of marsh fritillary. But try not to see these wasps as a wave of murderers. Instead, think of parasitism as the Neighbourhood Watch of a habitat, structuring ecological communities and policing populations. Obnoxious? Yes. Necessary? Absolutely. In fact, their critical role as ‘bio-control agents’ in agriculture has become a convenient alibi for their grim behaviour. Helpfully, butterflies reproduce quickly, so any dent in the population from a particularly potent wasp attack can typically be recovered the following year (i.e. in a world where climate change isn’t a concern and everything is wonderful).
‘Parasitism is only a problem if the habitat doesn’t have enough of a network to support such complex dynamics – it’s a really important part of a robust ecological network.’ Rachel Jones, senior ecologist for Butterfly Conservation and PhD researcher at the University of Exeter, confirmed the hunch that we humans tend to fear what we do not understand. We lash out and act up. We make unreasonable assertions. A growing body of (albeit uncertain) evidence suggests that a warmer world may destabilise this crucial interaction between marsh fritillary and Cotesia – that the absence of this dyad might unleash a wildfire of our orange marsh fritillary. Not what I was expecting, I’ll tell you.
A 2010 study at the University of Oxford found a muddy relationship with weather. Although weather is unlikely to dictate the health of marsh fritillary populations to the extent of, say, habitat quality and connectivity, the authors suggested that sunnier springs could cause the marsh fritillary to emerge first and outrun the wasp. Similar work in Cumbria modelled how, without the supervision of the parasitoid, marsh fritillary populations will expand, run out of Devil’s-bit scabious, starve, and local extinctions will increase. In short, the loss of this essential population regulator could (in theory) hasten the butterfly towards extinction. Bibbidi-bobbidi-bloody-boo.4
We would be unwise to forget that this wasp has persisted for a reason. Like all those in middle management, these wasps are in a constant state of flux, flip-flopping between being followers and leaders as they urge their haphazard habitat towards a state of balance. As you might expect, a large and well-connected habitat will insulate marsh fritillary colonies against extreme attacks from Cotesia but, crucially, will still allow the wasps to play the part of the essential bio-control buffer in maintaining sustainable populations. It’s that classic predator/prey anecdote where each species is each other’s alibi for life. No amount of data can determine what will happen to this unique, co-evolved dynamic in a warmer world. Contemplating what might happen does, however, bring forth a glaringly obvious conclusion: that nature is a lot more bloody complicated than we thought.
Back in the heady noughties of 2006, a study by the University of Exeter predicted that the marsh fritillary would become extinct across most of Britain by 2020 if conditions didn’t change. As I write, it is 2020, and I can confirm that the species is not yet extinct from most areas – but remains one of the UK’s fastest declining species. Yes, 14 years down the line, change has arrived. But it is the selfie, Hinge, Prime delivery, Uber, pandemic kind, you know? We haven’t yet decided to sell up and align with the greener way of living. That would surely be far too radical.
Ironically, the marsh fritillary was almost born to die. ‘It’s a classic metapopulation5 structure,’ Caroline told me. ‘This butterfly blinks in and out of extinction over time, even within connected habitat.’ Oh dear. If this ‘blinking’ is as frenzied as that of a certain, rather creepy IT teacher at school, then I’m afraid only God can save the marsh fritillary. Far from anything new, toying with death is part of the narrative tension that writes the marsh fritillary into freedom – conquering new areas and developing sturdier colonies. One year, a colony could collapse when changes in grazing reduce the availability of Devil’s-bit scabious. The next, it may be hammered by a demented weather event.
But, as Caroline said, ‘In the grand scheme of things, it doesn’t matter – because in an ideal world you’ll have colonies dotted throughout the landscape and they’ll easily recolonise – you will then have a landscape at equilibrium.’ Striving for ‘equilibrium’, of course, being the collective itch across life on Earth. From cell division to circadian rhythms to harmony within the home, we only know we need it after it’s gone. ‘Boom and bust is part of nature,’ Caroline stressed, ‘but if it happens in a rubbish habitat, the butterflies have a slim chance of survival in the long term.’ Oscillate in lush lowland grassland – even drier chalk grassland with pleasing foliage corridors – and the boom and bust should be as trivial as an unexpected item in the bagging area: short-term rage, long-term truce.
Please note that a marsh fritillary wants to be on the move. Not a ridiculous cross-continent migration like the painted lady,6 but some localised fidget is to be expected. A ‘dispersal’ gene is programmed into fritillary DNA – but even a hedge can be a barrier for social butterfly mobility, which is pretty unfair. Smaller, more isolated patches render the innate urge to ‘move’ redundant – the next nearest site is too far away. With winter flooding increasing and English summer temperatures becoming hot enough to fry an egg on your face, these events are already contributing to low recovery rates and delaying colonisation across the Bodmin populations, even when the habitat is fritillary-friendly.
We can optimise connectivity by creating clear flight paths between a network of good patches. ‘You could have chalk grasslands and farmland in between,’ admitted Rachel, ‘but that farmland between habitat patches could be softened with margins, buffer strips and nectar sites – it’s not as hostile as a huge field of barley or wheat.’ Trouble is, our landscapes are changing at a pace with which nature struggles to keep up. Our hunger for development is not giving nature enough time to respond. Not ideal when we have created a world that craves instant response. We’re not giving this butterfly long enough to reply.
Even in places (like Bodmin) where the habitat has altered for the better, an undercurrent of angst means that fragile species like the marsh fritillary remain in a state of ‘extinction debt’ – where they are, quite literally, indebted to extinction and owe it their life. This term soberly refers to a ‘delayed’ extinction event, where a series of dire circumstances should have led to species disappearing – but haven’t. Thus, the species (i.e. marsh fritillary) exists in a sorry state of limbo, waiting for the inevitable. ‘There is a balance between a watchful eye and letting habitat become totally reclaimed.’ said Caroline. ‘It’s a classic “Goldilocks” scenario of habitat suitability.’ Makes sense. Such logic is applied elsewhere, from economics to the habitable zone around a star. Balance must exist somewhere between the sweaty human grip of nature’s scruff and total abandon.
A good example lies in the choices we make for the land. Devil’s-bit scabious doesn’t do itself any favours by being a tasty plant for sheep (the most aggressive grazers). Historically, large areas of sheep grazing in the South West (and Scandinavia, for that matter) have driven a gross loss of plant structure – and food sources for the marsh fritillary. Not only that, but overgrazing can expose a more significant issue. ‘It can make a habitat prone to drought,’ mused Rachel. ‘We don’t have enough data to know whether the Devil’s-bit scabious will be able to withstand it, as populations can tolerate occasional drought. But it’s the frequency and intensity of recent droughts that could be the killer.’
But, weirdly, Caroline explained how a total abandonment of grazing could be just as detrimental. ‘We need grazing to maintain the mix of short to long sward that Devil’s-bit scabious and the butterfly need – but when it’s too heavy, that variation is lost.’ Gotcha, Goldilocks. Populations of marsh fritillaries in areas of Dorset were up fivefold where grazing was ‘recently abandoned’, i.e. not mown to the ground, but also not wild and disorderly. Much like a decent haircut, it is the height of grassland that is key. When you’re a butterfly with a diameter that spans the average length of the human little finger – and you’re striving for a mate and a place to lay your eggs – an ungrazed swathe of grassland is a demoralising fortress. Equally, however, you don’t want to have to fly long distances over barren lawns bearing your heavy, eggy burden. So, Caroline’s team found that a ‘lightly grazed’ area yielded a vegetation height of 5–20cm, which seemed to produce lovely, connected plots of Devil’s-bit scabious. Scales a-balanced.
For us, ‘connectivity’ simply requires a virtual network bot to guide you, a sweating you to plug some wires into a router. But for the marsh fritillary? Simple recruitment of gentle grazers and a healthy willingness among humans to collaborate with each other (and with ecology, obvs) will suffice. ‘The critical need for survival is good quality habitat, followed by large patches of good quality habitat, followed by well-connected land,’ Caroline explained, stressing how important the latter element is for enabling colonisation in the event of local extinctions. ‘Populations can persist without mixing, but if local extinction occurs, re-colonisation is impossible.’
When I saw them, I was mentally composing a disgruntled email to lovely Cornwall Butterfly Conservation’s Jo, huffing at the so-called ‘guaranteed hotspot’. Then, not one, but two flickers of orange confetti scattered in the wind against a blackened Bodmin sky. A fragile carousel, dancing with a higher purpose. I was lost to the moment. A glimpse so fleeting, I wondered whether it really happened. Still do. Ask any butterfly fan, though, and the consensus is that you just know when you’ve seen a marsh fritillary. Modern society has primed us to view every novel encounter with nature as something to feel deeply moved by, as though we have uncovered some fundamental truth that has evaded seasoned naturalists for centuries. When in fact, it’s merely a chance (fine, a slightly engineered) rendezvous with something that is not another person.
The pair I saw disappeared as fleetingly as they had arrived, behind the granite fallout from the tor – seeking asylum in a patch of grass that looked as though someone had scribbled it with a biro. Perhaps they had gone to mate, lay eggs, conclude their chapter? Such is their commitment to the cause. Or maybe this pas de deux was their finale?
The laden calm before the weather shifted blanketed Breney Common. Anticipation was replaced with a kind of tipsy placidity. Finding a slab of rock on which to sit and eat my apple, I enjoyed that rare pleasure of a total absence of thought.
There’s a nostalgia that comes with pursuing a butterfly. The simplicity of a day out with a packed lunch and a wholesome can-do attitude revives a time of ease and contentment when decisions and things were less of a labyrinth and more of a leafy avenue with clear views into the distance. I floated this idea past Rachel and was comforted with the notion that I wasn’t being a total salad. She told me the marsh fritillary is just associated with a lovely landscape. That it was the first butterfly she had worked on. Recalling the childlike joy she felt upon seeing it for the first time, ‘It just symbolises a landscape that was – and I don’t think people realise that.’
A day like the one I spent on Helman Tor is childhood revisited. Sweet as summer rain. Fabricating memories, maybe, but these are surely the ones to bookmark? Gorse brushed against my backpack, sounding like hair might if it swept across canvas. I wondered – if an artist had painted this entire scene, where would they place me in the landscape? Would I belong in it at all? I rolled a spiral of fern into my fingers and ground it into some kind of pesto, closed my eyes and smelled it.
In more ways than one, Bodmin is the overlooked success story. Neighbouring Dartmoor has a similar resumé and has provided valuable lessons that inspired later work on Bodmin. A long-term lack of grazing led to a general vibe of disarray, overpowering Devil’s-bit scabious and leaving Dartmoor’s population of marsh fritillaries isolated and pissed off. In the spirit of not-letting-it-all-go-to-shit, Butterfly Conservation launched the Two Moors Threatened Butterfly Project, placing actual humans (rogue!) on the ground to increase connectivity, add grazers, train staff and conduct guided walks. In a wild, brilliant example of archaic abandon, landowners and farmers were supported and educated by agri-environment schemes on how to cultivate in favour of the butterfly, at no cost to their productivity. Unsurprisingly, connectivity quickly increased. Flight paths of the butterfly nearly halved to 260 metres. Larval food webs rose by 1,080 per cent, and 71 per cent of sites across Dartmoor are now actively managed for the marsh fritillary, earning it a well-deserved position as a national stronghold for our little aurinia.
Back to Bodmin, and between 2017–2020, Butterfly Conservation launched All the Moor Butterflies. Twenty-nine new marsh fritillary sites were restored thanks to 165 hectares of farm-specific habitat improvement – a roaring success. Traditional practices of ‘swaling’ (controlled burning7 ) and rotational cattle grazing are optimal for maintaining the numbers here in Cornwall – repaying the extinction debt accumulated across these Cornish moors. In short – conservation can work. And we should stop being so surprised by this.
In an age where Build, Build, Build! and Shop for Britain! seem the societal hymns, small and connected patches jammed with butterfly food plants is all we ask for. Keeping ironies intact, Britain’s future-proofing strategy has so far consisted of: debate > million-pound flood-defences > commission Progress Report #5,000 > debate > design overpriced electric transport > convene Nothing is Getting Done Committee > fashion ‘net-zero’ rhetoric > debate > plant some trees. When all we need are stepping stones of quality habitat to lead any fragile species away from a battering – us included. We seem to forget that it is in our best interest to preserve the habitat of the marsh fritillary. Sure, we would sorely miss it as an upland jewel, but its absence would be symptomatic of a landscape in failing health. A vaccination for that disease will never exist. Sorry.
‘Everything is interlinked,’ said Rachel, ‘that’s what we keep forgetting.’ This butterfly is teaching us a lesson. Quite right. Coaxing populations elsewhere across the country has had mixed results, but the beauty is we already have pockets of colonies sitting on habitats that we would be wise to preserve. It’s a question of capitalising on existing populations, making the habitat as rich a tapestry as possible, so that if climate change does give us an almighty kick up the arse, the resilience is there to fend off the challenge and keep these butterflies in play. As Rachel pointed out, ‘creating strong networks of habitat will bolster those existing populations. Sustained through the legacies of projects and management, the butterflies will be able to track naturally.’ That sounds good.
There is a chance that the marsh fritillary’s curious ability to occupy different niches around the world might stand it in good stead as our climate becomes more Mediterranean. In southern Spain, it swaps moist tussocks for woodland and Devil’s-bit scabious for honeysuckle. Caroline reflected, ‘In 50 years, the marsh fritillary in England might be in the woods eating honeysuckle, but we must maintain populations in the present, so future generations have the chance to adapt. Who knows … but it’s a thought.’
Rain finally announced my cue to leave. The kind of rain that is exclusive to a British moorland. Despite the morbid reality of being drenched, cold and hungry, the freedom of being outdoors and powering my way home felt as physically freeing as taking off a bra at the end of a long day. My hands were frozen and weirdly coloured, barely able to shift gears, let alone use the brakes. I had never been wetter. The moment had all the components of a scenario that should sap the soul – but, weirdly, I felt grand. Having gone far too well anyway, it made sense that I had a full-bodied experience right to the day’s end.
I reckon the marsh fritillary is the perfect metaphor for change. It lives only as a result of extraordinary transfiguration. But I also reckon we are very quickly writing it out of its own story. Like a teacher aggressively circling ‘marsh fritillary’ with a red pen, commenting ‘does this add anything???’ – before we’ve taken the time to consider whether we could be the ones who need the edit.
I made the most of the train journey back to Exeter, stripping off clothes for the second time that day and transforming the empty carriage into a launderette. I felt shaky. Hating myself for what swiftly emerged as appalling catering planning when all available food opportunities while travelling were on pause. I was branded by the day; chain grease tracked up my calf like some heavy-metal tattoo. Changing trains at Plymouth, I latched on to the only available vending machine like a moth to a lamp, buying two Twirls and some yoghurt raisins, and waited on the platform, damp and shivering in a sugar-trance.
Naturally, not a drop of rain had fallen beyond Bodmin. I arrived home as moist as Breney Common itself. Eurgh. Good practice, though, I thought, watching tiny bubbles burst around the seams of my sodden trainers. My next trip promised even more water. To Wales.
Notes
1 Author of The Wind in the Willows (1908) – if you haven’t read it, stop reading this and do that first. And then please come back.
2 FYI, the large copper is protected under European legislation but became extinct in Britain in 1851. The large blue became extinct in 1979 but has been successfully reintroduced to Somerset and Gloucestershire. Hooray.
3 The fancy word to describe butterflies and moths (keep a note for your next pub quiz).
4 Written in 1948, ‘The Magic Song’ was first heard in the 1950 film of Cinderella.
5 ‘Metapopulation’ simply means a group of populations of the same species – separated by space. For example, London and its boroughs house a metapopulation of humans (sounds grim, actually).
6 An annual summer immigrant to the UK, these butterflies undertake one of the most astonishing migrations. Cruising at speeds of 30mph, painted ladies clock a 9,000-mile round trip from tropical Africa to the Arctic Circle. It is thought that migratory butterflies orientate their flight using the sun as a compass.
7 Not to be confused with other South-Westerly activities such as ‘welly wanging’ or ‘wassailing’.