This week’s transect delivered a larger burst of butterfly brilliance, with 305 individuals from 15 species – our second-highest Week 11 total on record, just behind the extraordinary 517 seen in 2020.
Not surprisingly, the warmest survey day of the year so far had the butterflies out in force. Numbers were driven by a major surge in Small and Essex Skippers, Marbled Whites (spotted in every single section) and Meadow Browns, now dominating the summer landscape.
While Common Blues and Green Hairstreaks continue their decline, we were pleased to spot two Small Blues – tiny but mighty – one enjoying Hither Field and the other basking on Coneyboro Hill.
​The season is clearly heating up, and if this momentum continues, we could be fluttering toward a record-breaking summer.

Count details:
123 Marbled White
  90 Meadow Brown
  36 Small/Essex Skipper
  (inc. 2 Small & 1 Essex)
  20 Small Heath
  10 Common Blue
    7 Dark Green Fritillary
    4 Brimstone
    4 Large Skipper
    3 Speckled Wood
    2 Green Hairstreak
    2 Small Blue
    1 Brown Argus
    1 Large White
    1 Small Copper
    1 Small White
Total: 305 butterflies from 15 species.
​For more info on these species visit butterfly-conservation.org

Meadow Brown (Maniola jurtina) – a familiar flutter in summer meadows, but full of surprises.

• As our figures indicate, it’s one of the most widespread and abundant butterflies in the UK, often seen flying even on dull or windy days when others stay grounded.
• Males and females look different – females have brighter orange markings, while males are browner and more subdued.
• Unlike many butterflies, Meadow Browns can live for several weeks, allowing them to be active from June well into September – a long season for a short-lived insect.

Transect 10 brought a sharp drop in butterfly numbers – a reminder that nature doesn’t always follow a smooth curve. With skies turning overcast and winds picking up, conditions weren’t ideal. We may also be entering the well-known ‘June Dip’, a seasonal lull when spring butterflies fade and summer species are still on the rise.
But it wasn’t all doom and gloom. Despite lower overall numbers, we recorded 17 different species –our highest species diversity since July 2020. Even better, several first appearances of the year brightened the count: Large Skippers, Large Whites, Marbled Whites, and both Small and Essex Skippers made their seasonal debut.
So while the numbers took a dip, the variety hints at exciting things to come. We’re now on the cusp of the main summer emergence, when butterfly activity traditionally soars – so keep your cameras ready and your eyes sharp!

Count details:
32 Meadow Brown
11 Small Heath
10 Common Blue
  9 Marbled White
  4 Small Blue
  3 Dark Green Fritillary
  3 Dingy Skipper
  2 Brimstone
  2 Green Hairstreak
  2 Grizzled Skipper
  2 Large Skipper
  2 Small/Essex Skipper
  1 Holly Blue
  1 Large White
  1 Painted Lady
  1 Red Admiral
  1 Small Tortoiseshell
Total: 87 butterflies from 17 species.
For more info on these species visit
​ butterfly-conservation.org

Marbled White (Melanargia galathea) – a strikingly patterned beauty of summer meadows.

• Despite its appearance, the Marbled White is actually part of the brown butterfly family, not the whites.
• It prefers unimproved grasslands and thrives in areas rich in wildflowers and tall grasses like red fescue.
• The caterpillars hatch in late summer but don’t feed right away – they enter hibernation almost immediately, only beginning to eat the following spring.

Small Skipper (Thymelicus sylvestris) – a tiny burst of orange with big energy.

• Often mistaken for a moth, this butterfly rests with its forewings angled upwards, giving it a distinctive, jet-plane posture.
• Males can be identified by a bold black line across the forewing – called a sex brand – used to release pheromones and attract females.
• Its caterpillars feed on Yorkshire Fog grass, and cleverly spin a cocoon on to the grass blades as a shelter from predators.

Transect 9 brought with it one of the warmest days of the year so far – and the butterflies responded accordingly. Making its seasonal debut was the Meadow Brown, a true summer stalwart whose numbers are likely to rise dramatically in the coming weeks. Meanwhile, the Painted Lady continues to make itself at home, joined this week by a Small Tortoiseshell, a vibrant visitor more than worthy of top billing on any butterfly page. (Photo above.)
Although the Small Blues were sadly fewer this time, another first of the season took us by surprise: a Dark Green Fritillary whizzed past at high speed in Fames Rough, a thrilling blur of orange wings.
Fames Rough remains our butterfly stronghold, with 78 individuals recorded in Sections 3 and 4, but, encouragingly, sightings were more evenly distributed across the rest of the transect this week. The totals for each weekly outing are still holding up strongly – this was our highest ever week 9 count.

Counted this week:
45 Common Blue
42 Small Heath
14 Brimstone
14 Green Hairstreak
13 Meadow Brown
  9 Dingy Skipper
  7 Large Skipper
  6 Holly Blue
​  3 Peacock
  3 Speckled Wood
  2 Dark Green Fritillary
  2 Small Blue
  1 Painted Lady
  1 Small Tortoiseshell
Total: 162 butterflies from 13 species.

For more info on these species visit butterfly-conservation.org ​​

Small Tortoiseshell (Aglais urticae) – a garden favourite with hidden strengths.

• Despite its delicate looks, this butterfly is tough – it overwinters as an adult, often sheltering in sheds or attics until spring.
• Its caterpillars feed exclusively on nettles, turning a common weed into a vital food source.
• Once abundant, its numbers mysteriously declined in the early 2000s – scientists now suspect a parasitic fly may be to blame.

Dark Green Fritillary (Argynnis aglaja) – a fast flier with a taste for the wild.

• Despite the name, it’s not very green – its name comes from the greenish sheen on the underside of its hind wings.
• It’s one of the UK’s speediest butterflies, zipping across grasslands in a blur of orange and black.
• Its caterpillars rely on violets – especially Dog Violet – as their sole food source, laying eggs near tufts where the larvae can safely hibernate over winter.

Although the sky flirted with cloud cover now and then, the temperature climbed a few notches this week – enough to send butterfly activity soaring once again. It’s a rare treat to spot 14 species on a single transect, but that’s exactly what we recorded. Once again among them was the enigmatic Painted Lady of Fames Rough (surely the title of a Victorian novel!), joined by another appearing next door in Coneyboro Hill.
But the real surprise? A tiny marvel no larger than your thumbnail – the Small Blue. Making a seasonally early appearance, this dainty butterfly is typically seen in ones and twos, hugging the few flowering clumps of its sole food plant, Kidney Vetch, which we've been carefully encouraging in Chipstead Valley, particularly around the Lagoon near Outwood Lane.
So imagine our astonishment when, for the first time ever, seven Small Blues were spotted together in Hill Wood Field (Section 7) – nowhere near any Kidney Vetch, but instead fluttering calmly in a small patch of brambles and long grass beside the path. What drew them to this unexpected hangout? The butterflies aren’t telling, but they did pose obligingly for our photos.

We recorded:
101 Common Blue
31 Dingy Skipper
22 Brimstone
21 Small Heath
13 Green Hairstreak
  7 Small Blue (previously seen
​     early June to July)
  3 Peacock
  2 Holly Blue
  2 Painted Lady
  2 Small White
  1 Brown Argus
  1 Grizzled Skipper
  1 Orange Tip
  1 Speckled Wood
Total: 208 butterflies from 14 species (it’s not often we reach 14 species).

For more info on these species visit butterfly-conservation.org ​

Small Blue (Cupido minimus) – tiny in size, mighty in charm.

• It’s the UK’s smallest resident butterfly, with a wingspan of just 16–27mm  –  easily mistaken for a flying speck of ash.
• Despite its name, the Small Blue is mostly brown-grey on top; the blue is limited to a subtle dusting on the male’s wings.
• It lays its eggs on just one plant: Kidney Vetch, making conservation of this wildflower vital for its survival.

A cool northerly breeze drifted through several parts of the transect this week, dialling down the temperature – but not the butterfly activity. Generous helpings of sunshine more than made up for the chill, giving our survey another boost.
Hot on the heels of last week’s record-breaking total, this week’s count reached 187 butterflies across 13 species – our second-highest total ever for Week 7.
The Green Hairstreak also had a strong showing, with 12 individuals spotted in a single section – just shy of our record of 13 from Week 6 in 2018, and matching tallies from 2019’s Weeks 5 and 7. Clearly, this little green gem enjoys making history.
But the real showstopper came courtesy of Fames Rough, where we were treated to a surprise visit from a Painted Lady – a glamorous globe-trotter that had travelled a very long way for a brief encounter in the sun (see below).
What to call the male of this species? Perhaps a Tattooed Gentleman!

​We recorded:
69 Common Blues
30 Brimstones
29 Dingy Skipper
26 Small Heath
12 Green Hairstreak
  5 Small Copper
  4 Peacock
  3 Brown Argus
  3 Grizzled Skipper
  3 Speckled Wood
  1 Holly Blue
  1 Orange Tip
  1 Painted Lady
Total: 187 butterflies from 13 species.

For more info on these species visit butterfly-conservation.org 

Painted Lady (Vanessa cardui) – the globe-trotting marvel of the butterfly world.

• Painted Ladies migrate thousands of miles – from North Africa to the UK – without a map, compass, or satellite navigation.
• They’re the most widespread butterfly on Earth, found on every continent except Antarctica.
• Unlike many UK butterflies, they don’t hibernate – each generation keeps the migration going, like a relay race across continents.

As Shakespeare once mused:
Sometime too hot the eye of heaven shines,
And often is his gold complexion dimm’d.
That 16th-century weather report still holds true for British summers – although today we’d probably call it 'sunny intervals with a chance of poetic reflection.' And sure enough, this week’s butterfly survey enjoyed just such weather: warm, bright, and butterfly-approved.
The mild temperatures triggered a fluttering boom across the transect, with 221 butterflies recorded—roughly three times our average for Week 6. The stars of the show? Common Blues, Dingy Skippers, Small Heaths, and Brimstones, all out in force. Once again, Fames Rough lived up to its reputation as a butterfly hotspot, contributing a whopping 114 to the total.
As cooler conditions creep in, we’ll be watching with interest to see if next week’s numbers continue to soar – or take a turn for the verse!

Count details:
88 Common Blue
42 Dingy Skipper
34 Small Heath
24 Brimstone
10 Brown Argus
  8 Green Hairstreak
  6 Peacock
  2 Grizzled Skipper
  2 Holly Blue
  2 Orange Tip
  2 Small Copper
  1 Green-veined White
​Total: 221 butterflies from 12 species.

​For more info on these species visit butterfly-conservation.org     

Small Heath (Coenonympha pamphilus) – a master of subtlety and survival.

• This butterfly rarely opens its wings when resting, making it easy to overlook despite being widespread.
• It can be active in cooler, breezy conditions when other species stay grounded – thanks to its ability to absorb heat quickly.
• The Small Heath may have up to three generations a year, adapting its life cycle to fit local weather conditions and habitats.

Spindle Ermine Moth Caterpillars (Yponomeuta cagnagella) – Nature’s spooky silk-spinners.

• These caterpillars create massive communal webs that can completely shroud spindle trees, giving them a ghostly, haunted look.
• Despite their eerie appearance, they don’t usually kill the tree – most bounce back after the caterpillars pupate and move on.
• Each web can house hundreds of caterpillars, all working together like a tiny silken city of leaf-munching roommates.

Mating Brown Argus Butterflies (Aricia agestis) – a close encounter of the butterfly kind.

• Brown Argus butterflies are often mistaken for female Common Blues, since both sexes are have brown with orange spots on the underside.
• They have two broods a year, and mating usually takes place soon after the butterflies emerge – no time wasted!
• Their courtship is a delicate dance, with males using subtle wing flicks and scent scales to attract a mate.

The hottest May Day on record didn’t just have humans reaching for the sun cream – it sent our butterfly count soaring too. Unsurprisingly, the blazing sunshine gave our sun-worshipping species a major boost, resulting in a record-breaking 151 butterflies spotted on this transect – the highest ever for week 5 of the season.
A remarkable 128 of those were found in just the first five sections –Stagbury, Great Parsons, Coneyboro, and Fames Rough – clearly the prime destination for nectar-hunters and basking beauties.
We were delighted to see Speckled Woods make a surprise return to their usual shady hangouts, a first appearance here in some time and a hopeful sign for this woodland-loving species. Also spotted was the dashing Red Admiral, a familiar favourite that often migrates from the continent and seems equally at home flitting through gardens or sunning itself on paths.
Butterflies love a heatwave – and apparently, so do the record books!

Count details:
41 Dingy Skipper
36 Small Heath
32 Brimstone
14 Grizzled Skipper
  6 Common Blue
  6 Peacock
  5 Brown Argus
  4 Green Hairstreak
  3 Holly Blue
  2 Speckled Wood
  1 Orange Tip
  1 Red Admiral
Total:151 butterflies from 12 species.
​For more info on these species visit butterfly-conservation.org

Holly Blue (Celastrina argiolus) – a high-flying beauty with seasonal tastes.

• It's one of the earliest blues to emerge in spring, often seen flitting high around holly bushes (hence the name).
• The caterpillars are picky eaters, feeding on holly in spring and switching to ivy in late summer – two broods, two diets.
• Unlike many butterflies that stay close to the ground, Holly Blues often fly high among trees and shrubs, making them easy to miss unless you're looking up.

Speckled Wood (Pararge aegeria) – the shady woodland specialist with a twist.

• Unlike most butterflies, it prefers dappled shade over open sun, often seen dancing in sunlit glades and woodland rides.
• Males are fiercely territorial, spiralling into mid-air battles to defend their favourite sunspots.
• It can overwinter either as a caterpillar or chrysalis, giving it flexibility to cope with the UK's unpredictable seasons.

Orange Tip (Anthocharis cardamines) – a springtime splash of colour with hidden talents.

• Only the males have the bright orange wingtips – females are white and often mistaken for other white butterflies.
• It’s one of the first butterflies to appear in spring, often seen darting through hedgerows and along woodland edges.
• Its caterpillars are cannibalistic and will sometimes eat their own kind to eliminate competition for food.

This week’s transect brought a fluttery change for the better. With a welcome (if brief) boost in temperature, the butterfly scene really stepped up its game. Species diversity soared compared to last week, as more Dingy Skippers took to the air – and they weren’t alone. Making their seasonal debut were the radiant Small Copper and the charming Small Heath, clearly ready to join the springtime party.
Even more intriguing was the early arrival of two butterflies who clearly missed the memo about their flight times starting in May: the photogenic Common Blue and the elegant Brown Argus both checked in ahead of schedule. Whether they were keen or just impatient, they certainly made a surprise arrival midway through the afternoon.
Their reward? Exclusive admission to the transect’s ‘first-class lounge’ (our well-earned refreshment break at Fames Rough), where tea, snacks, and butterfly banter are always in-flight entertainment.

Common Blue (Polyommatus icarus) – the classic blue with a wild side.

• Males are a brilliant sky blue, while females vary from dull brown to bright blue – no two are quite the same.
• It’s the most widespread blue butterfly in the UK, thriving in gardens, grasslands, and even roadside verges.
• Its caterpillars communicate with ants by sound and scent, earning protection in exchange for sweet secretions.

Small Copper (Lycaena phlaeas) – a tiny butterfly with a fiery personality.

• Its bright orange wings with bold black spots make it one of the most eye-catching small species.
• Despite its delicate appearance, it’s fiercely territorial – often chasing off much larger butterflies.
• It can produce up to three generations a year, making surprise appearances from spring right through to autumn.

Brown Argus (Aricia agestis) – a subtle beauty with secrets.

• Though it looks similar to female Common Blues, it has no hint of blue – just rich chocolate-brown wings with orange spots.
• It’s a sun-lover often found in warm, dry grasslands, basking with wings wide open on bare ground.
• Its caterpillars feed on low-growing plants like rockrose and geraniums – and they’re guarded by ants in return for sugary rewards.

The weather for our Easter transect was cool, overcast, and a bit reluctant to play nice. For much of the afternoon, the butterflies stayed tucked away, presumably sipping hot nectar indoors. But just when we thought we’d missed out, the sun peeked shyly through the clouds … and out they came!
Among the brave flutterers making a fashionably late entrance were the Dingy Skipper, the Grizzled Skipper, and the Green-veined White – names that sound like they come from a woodland fairytale, but are real-life characters now appearing in a meadow near you. And that meadow is Fames Rough, where most of this week’s butterfly action was recorded.
As the figures show, butterfly numbers are doing their own weather forecast – rising and falling in step with our current temperature rollercoaster. It’s a delicate dance between sunshine and wings, and this week the rhythm was definitely a slow one.

Dingy Skipper (Erynnis tages) – more charming than its name suggests.

• Despite its dull brown colour, it’s actually a member of the fast-flying, sun-loving skipper family.
• It prefers warm, open habitats like chalk grasslands and brownfield sites – often basking with wings spread wide like a moth.  
• Its caterpillars live in a self-made shelter by folding leaves of Bird’s-foot-trefoil, their main food plant.

Grizzled Skipper (Pyrgus malvae) – a tiny speedster with a chequered charm.

• Its distinctive black-and-white ‘grizzled’ pattern helps it blend perfectly into stony or gravelly ground.
• It’s one of the earliest skippers to emerge in spring, often zipping low over the ground in quick, darting flights.
• The caterpillars feed on wild strawberry and other plants in the rose family, hiding in cleverly folded leaves.

Green-veined White (Pieris napi) – a master of disguise in the meadow.

• Unlike the similar-looking Small White, its underwings have delicate greenish veins that help it vanish among foliage.
• It prefers damp, grassy habitats like meadows, woodland edges, and riverbanks – often overlooked despite being widespread.
• Females are picky egg-layers, choosing only the freshest wildflowers like cuckooflower and garlic mustard for their caterpillars.

An afternoon bathed in glorious sunshine and skies so blue they looked photoshopped – perfect weather both for butterflies and the volunteers counting them. This was only our second outing of the season, but what a difference a week makes! We nearly doubled last week’s total, proving that the butterflies were just waiting for a proper spring day to stretch their wings.
Leading the charge once again were the flashy Peacocks and widespread Brimstones, the latter spotted in every single one of the 12 transect sections – as if they’d been assigned to patrol.
We also welcomed some fresh names to the party, with season-first sightings of the darting Dingy Skipper and the dazzling Green Hairstreak, pictured below in all its emerald glory.

Brimstone Butterfly (Gonepteryx rhamni) – Nature’s early riser.

• It’s thought to be the original inspiration for the word butterfly due to the male’s buttery yellow wings.
• Brimstones can live up to a year – remarkably long for a butterfly.
• Their leaf-shaped wings make them masters of camouflage when resting among foliage, like the butterfly on the right.

Peacock Butterfly (Aglais io) – a springtime stunner.

• Its striking ‘eye-spot’ markings are used to scare off predators like birds.
• Despite its delicate looks, it hibernates through winter and is one of the first butterflies seen in spring.
• When threatened, it makes a hissing sound by rubbing its wings together.

Green Hairstreak (Callophrys rubi) – a tiny gem of spring.

• Though its upper wings are brown, it always rests with wings closed, showing off its shimmering green undersides.
• It’s the only green butterfly in the UK, perfectly camouflaged among leaves and grasses.
• The family name Callophrys is a Greek word meaning ‘beautiful eyebrows’.