Mill Hill (June 2013)


Autumn Downland Butterflies (August):
Chalkhill Blue (male)
 Meadow Brown (female)
Wall Brown
Adonis Blue
Chalkhill Blue

Noticeable summer plants of the upper meadows include Greater Knapweed, Hardheads (=Lesser Knapweed), Field Scabious, Meadow Cranesbill, Alexanders, Pyramidal Orchids, Plantains, Melilots, Meadow Vetchling, Yarrow, Eyebrights, Musk Thistles, Hounds-tongue*, Perforate St. John's Wort*, Great Mullein* and many others. Herb Robert is found amongst the scrub.
(*notably on disturbed ground.)

Some Indicator Plants of Ancient Downland

Horseshoe Vetch (Photograph by Andy Horton)
Autumn Gentian
Horseshoe Vetch
Common Milkwort
Dog Violet
Autumn Gentian

Other indicators on the lower slopes include Dropwort, Autumn Ladies Tresses (upper plateau), Hairy Violet, all of which are rarely found on pastures, restored wildlife meadows or agricultural downland. Other downland plants that are more likely on the biodiverse down herbland are Wild Thyme, Carline Thistle, Stemless Thistle, Squinancywort, Fairy Flax, Small Scabious, Common Centaury and Wild Basil. There are other more widespread wild plants like the Mouse-eared Hawkweed, Hawkbits, Autumnal Hawkbit, Bird's Foot Trefoil, Ground Ivy, Germander Speedwell, Field Speedwell, Sweet Violet, Self-heal and Yellow Wort.
Wild Flora and Fauna on Chalk   flickr
Adur Wild Flowers 2009


A large part (724 acres) of the downs including Mill Hill were presented to the people of Shoreham in 1937

Lower Slopes of Mill Hill, May 2006

Just over 30 acres still remain as public open land and a Local Nature Reserve.  This is divided into about 11 acres of grassland and meadows above the ridge, about 9 acres of scrub, the copse and glades at the northern end, and about half of the prime Chalkhill Blue area of 6.4 acres of herbland remaining. 6 acres has been lost to a Sycamore woodland on the southern slopes. 

This is low fertility chalkland not suitable for grazing. The top area is effectively a wild meadow and the lower slopes a rabbit warren dominated by prostrate (not the upright form) Horseshoe Vetch, Hippocrepis comosa

Link to the Mill Hill web page for 2009

Horseshoe Vetch

Chalkhill Blues:

Mill Hill is nationally important because of its population of Chalkhill Blue Butterflies. Estimates of the numbers are notoriously inaccurate. In the 1950s the population was estimated by R. M. Craske to be 50,000. This may be an exceptionally good year. I would estimate the numbers at that time to be nearer 25,000 for Mill Hill only. After the cattle grazing and thorn incursions the numbers plummeted to the most reliable estimate in 1960 of 6,000. The new road and Sycamore woodland further denuded the Horseshoe Vetch, Hippocrepis comosa, and bare chalk downland to a figure I have estimated at a top figure of 3,000 Chalkhill Blue Butterflies at the turn of the millennium (counted in 2003). Almost all these butterflies are now to be found on the six acres of the lower slopes.
Graham Hart in the 1990s estimated the numbers at 6,000. This is not out of the question and this would accord with the R. M. Craske estimate of 50,000. This would be the maximum population density that could be expected on the carpets of Horseshoe Vetch (based on German figures).
Protection of the current population requires man management of the scrub incursions, which means removal of the Privet

Text by Andy Horton Calcareous Grassland Message
"Our family lived at The Mill House, Mill Hill, from around 1933 until about 1967, and every July we saw the "Butterfly Men" walking past onto the Downs. My father used to tell us that they were interested in the blue butterflies."
Heather Clark (née Eager), Ryde, Isle of Wight
Nearest Postcode:  BN43 5FH
Grid Ref:  TQ 210 074  (upper car park)
Geographic Link      OS Map
Google Earth Map
Magic Map of Mill Hill NR
Local Nature Reserve Designation
Natural England: Local Nature Reserves
Multi-Map (Bird's Eye View)

Threats to the Butterfly Downland site at Mill Hill
The butterfly lower slopes at Mill Hill are under serious threat by a natural process known as ecological succession where the woody shrubs like Privet, Brambles and Hawthorn invade the herb-rich slopes gradually turning the downs into woodland and eliminating the butterfly larval food plants especially the Horseshoe Vetch, Hippocrepis comosa, on which the Chalkhill Blue Butterflies rely. The remedy is by expert professional removal of the Privet on a regular basis. This job is now being undertaken by volunteers. 


OS Map

                                                                  Footpaths at Mill Hill

Map Geograph Satellite


Mill Hill 2015 Reports

28 December 2014

Kestrel Portraits
Photographs by Etienne Fournier
Please click on the images for the originals and more photographs

A Kestrel is usually a regular resident over Mill Hill. This superb study looks like a young bird.

19 October 2014

 Rough Hawkbit
 Smooth Hawk's-beard 
Crepis capillaris
 Lesser Hawkbit
 Spider, Xysticus, on Carline Thistle
 Common Carder Bee, Bombus pascuorum
on Carline Thistle
 Wild Basil
 Unidentified mushroom on the verge of Mill Hill Road north of the bridge

No butterflies were present on Mill Hill in a substantial breeze (Force 5). A Kestrel hovered over the top part of the hill to the west of the upper car park. The purpose of the trip was to try out my new camera on still subjects as the only critters vaguely noteworthy were two Common Darters, a bumblebee and a grasshopper over the lower slopes. In circumstances like this I make a mental note of the relatively few wild plants still in flower: Carline Thistle, Rough Hawkbit,  Bristly Ox-tongue, one or more Smooth Hawk's-Beard Crepis capillaris, a few diminutive Cat's Ear, one Centaury, a few Great Knapweed, a few Lesser Knapweed (=Hardheads), a few Wild Basil, one Ragwort, one Scarlet Pimpernel, one Creeping Thistle, one Sow Thistle, one Hogweed bush and that was all that were seen on the lower slopes and southern part of Mill Hill Nature Reserve. (The top part of Mill Hill would have added more, but it was too breezy for comfort.)  A mushroom was spotted on the verge of Mill Hill Road north of the bridge.

Carline Thistle

2 October 2014
Just as I was going to jot down that there were no butterflies seen on the lower slopes of Mill Hill, a tatty blue butterfly was disturbed at the northern end after ten minutes with only Crane-flies and a few grasshoppers moving about. This was the first of two male Common Blues in the late afternoon. Immediately afterwards the first of half a dozen or more Meadow Browns appeared, including a fine condition male. The most impressive butterfly was a good condition Wall Brown that landed briefly on a bare area of chalky earth. Last but not least was a probable Small Tortoiseshell that flew off rapidly.
The lack of butterflies was not surprising given the lack of nectar flowers except for the very frequent Carline Thistle in various stages of growth from one grey deadhead from last year to mostly plants with silver and copper leaves to new growths with green leaves. There was at least one diminutive Hardhead and Spear Thistle seen on the lower slopes with a few Wild Basil, a few Small Scabious and the closed flowers of Yellow Wort. There was one clump of Devil's Bit Scabious, and one of the the few flowerheads attracted a small bee, which might have been a species of Halictus. A few Hawkbits were seen.

 Old Erringham, Hay Meadow Harvest
 New Erringham, Buckingham Barn

The hay meadow below Mill Hill was already harvested for hay and the bales rolled up. By Buckingham Barn, one bale was being prepared to feed the cattle as they have appeared to have grazed the natural grass from the pasture to the east.
Adur Butterfly Report

Ivy Bee, Colletes hederae16 September 2014
On a warm (21.7 °C) humid afternoon a Kestrel swooped over the lower slopes. In the field below the hay was being harvested. I walked amongst the fresh growths of Privet which were now in berry. Butterflies were not seen until I reached the Carline Thistle and the blues were in such a tattered condition it was not so easy to identify them. Most of them were recognised as Adonis Blues and there were about fifteen of which about six of them were females. Some females attempted to lay eggs despite attention from the males. Small Heaths were courting and one pair were seen mating. There were at least a dozen of them and all were in fine condition. Meadow Browns were frequently seen as well in about the same numbers. Common Blues were infrequent but there were at least a few and there was at least one Brown Argus on Carline Thistle and probably more. A much large white butterfly must have been a Large White. Two Clouded Yellows fluttered over the lower slopes without pausing. One was very pale. Nearer the northern end of the lower slopes of Mill Hill, and sometimes near the path, there were small cliff edges of exposed soil and these were used by congregations of the Ivy Bee, Colletes hederae.
Colletes species
Adur Bees

Brown Argus on Carline Thistle
Adonis Blues

A flock of about fifteen Rooks suddenly appeared overhead. Flowering plants were not much in evidence. Carline Thistle showed a few new budding plants and older ones with leaves of green, brown and silver even on the same plant. There was even a grey dead plant from last year. I walked through the scrub and spotted a fresh Red Admiral. The middle slopes and top meadows were almost bereft of butterflies and the upper plateau only hosted a few Small Heaths.
Adur Butterfly List 2014

28 August 2014
Very autumnal weather for a week, and then I trekked up in Mill Hill on cool afternoon with a noticeable breeze, inimical for butterflies. I did manage to spot a probably Large White over the Dovecote Estate, and a Speckled Wood and an active Southern Hawker (dragonfly) at the top of Chanctonbury Drive. Mill Hill was breezy (Force 5) and cool with only a Small Heath seen on the southern upper part of the hill. Because, it was so uncompromising, I did not work the full transect of the lower slopes. I walked the chalky path and ventured down to see if Devils Bit Scabious was flowering. It was in small amounts, overgrown by Privet at the northern end. Carline Thistle provided attractive to the frequent butterflies that were only sent into flight when disturbed. I did not count but estimated the butterfly numbers at 22+ Meadow Browns, 23 (18+5) Common Blues, 18 (15+3) Adonis Blues, 2 (1+1) Chalkhill Blues, and 7+ Small Heaths.

Common Blue
Common Blue
Carline Thistle
Devils Bit Scabious
Meadow Brown
Carline Thistle

At least one Treble-bar Moth and one Yellow Shell Moth were disturbed as well as the tiny pyralid moths Pyrausta nigrata and Pyrausta purpuralis.
Cotoneaster was seen in a large patch on the lower slopes below the path. I had not seen a large patch before as usually take a different route.
Adur Butterfly Report

15 August 2014
I expected the gales and heavy rain of the last week to have deprecated the butterflies and there was not a single one to be seen at the mown open space at Chanctonbury Drive (north) on the way to Mill Hill. Numbers and variety were severely diminished on the lower slopes of Mill Hill, almost all of the 10 (7+3) Chalkhill Blues were in a faded, torn and battered condition. Adonis Blues were worn and frayed but not in the same state as the Chalkhill Blues, but only 23 (19+4) were recorded in the transect acre on a cloudy day without sun. The Adonis Blues included a mating pair. There were a six (4+2) Common Blues over the lower slopes with an estimated 50+ Meadow Browns (with many large females), about a dozen Small Heaths, and just the one positive Gatekeeper. A large vanessid was unidentified, probably a Comma and a white butterfly in the distance was most likely a Green-veined White. Small moths flitted in the undergrowth including the pyralid moths Pyrausta nigrata, Pyrausta despicata and the colourful Pyrausta purpuralis. Three Treble-bar Moths were disturbed. Many of the butterflies and moths may have been hiding as after I had completed the transect the sun came out briefly and there many more Adonis Blues and other butterflies in the same proportions. The distinctive Panorpa fly was seen amongst the Privet and Brambles on the lower slopes of Mill Hill. A Tenthredo Sawfly was attracted to Wild Carrot. A Common Carpet Moth was disturbed in the scrub.

Adonis Blues
 Adonis Blue
Carline Thistle
 Common Blues
Bird's Foot Trefoil
Adonis Blue
Carline Thistle 

In a pleasant contrast hundreds of fresh Common Blue Butterflies were everywhere in the flowery meadows of the middle slopes and upper meadows of Mill Hill. About three-quarters of these were males, but included plenty of small females and a few large pretty females. I checked the female Common Blues which were clearly most of them, just in case there was Brown Argus, but it was only a possible sighting. A Gatekeeper with a large bite out of its wing landed on Marjoram. Meadow Browns were frequent and on the top meadow plateau a Small Heath Butterfly settled. A really worn male Chalkhill Blue was seen on the middle slopes.
Adur Butterfly Report

8 August 2014
A Silver-spotted Skipper was photographed on Mill Hill for the first time.
Report & Image by Claire Sell
7 August 2014
Hundreds of butterflies flew over Mill Hill, but they were thinly spread without any hotspots, Meadow Browns everywhere, mainly Common Blues on the top and middle slopes.  On the lower slopes 43 (39+4) Chalkhill Blues  were counted on the transect acre, with almost as many Common Blues, 25 male Adonis Blues, an estimated 120+ Meadow Browns, 25+ Gatekeepers, occasional Small Heaths, four Marbled Whites, at least one Large White, one Green-veined White, one bright yellow Brimstone, at least four, possibly six Clouded Yellows including one white 'helice' variety, four Wall Browns and faded 6-spotted Burnet Moths and a Treble-bar Moth. On the top part of Mill Hill, there was also two Small Tortoiseshells as well as a Red Admiral, five male Chalkhill Blues and two Adonis Blues seen. A handful of Holly Blue Butterflies were seen on the huge garden hedge north of the bridge. A Hawker dragonfly flew over the hill.


There was a pyralid moth Pyrausta despicata on the lower slopes of Mill Hill

5 August 2014
In the morning I watched the maiden flight of several Adonis Blue males at Mill Hill. They perched on the abundant stems of Yellow Wort while drying their wings, occasionally discharging meconium fluid before heading off to patrol the slopes in search of virgin females, the first few of which are now out. Amongst the many other species present I was pleased to see a Silver-spotted Skipper, this was only the second specimen recorded on the hill. The previous evening my father found a full-grown Privet Hawkmoth caterpillar.

Report by Neil Hulme on Sussex Butterflies

1 August 2014
An exceptional variety of 20 different species of butterflies in an hour on the lower slopes of Mill Hill made up for a rather dismal number of Chalkhill Blues for what should be their peak time. There were hundreds of the restless Chalkhill Blues but they were thinly spread and the transect acre total was only 47. It appeared that many more were in flight after my count.

Hemp Agrimony (next to the southern steps) again proved attractive, and my first Painted Lady of the year was a persistent visitor with Red Admirals, Peacocks and a Small Tortoiseshell. Nearby, there were Speckled Woods and a Holly Blue. Other butterflies over the lower slopes, in the order of prevalence, were an estimated 120+ Meadow Browns, 35+ Gatekeepers, about 15+ Common Blues, about a dozen Small Heaths, about ten Green-Veined Whites, about eight Wall Browns all over the path and some in the long grass, about eight male Adonis Blues, a few Large Whites, a few Brimstones, one or two Marbled Whites, and one each of Clouded Yellow, Small Skipper and Dark Green Fritillary. Later, two pairs of Chalkhill Blues were seen in mating tussles, which were not completed whilst I was there. There were also a few 6-spotted Burnet Moths and a Treble-bar Moth.
I curtailed my visit rather rapidly as the sun went behind a cloud and rain looked imminent.
Adur Butterfly & Large Moth List 2014

30 July 2014
An afternoon circular trip over Mill Hill produced 18 different species of butterfly, including a restless 69 male Chalkhill Blues, the first of the second brood Adonis Blues (2), at least three immigrant Clouded Yellows, a few vanessids visiting Hemp Agrimony, ubiquitous Meadow Browns, very frequent Gatekeepers, six Wall Browns, occasional Marbled Whites and other resident species expected on chalk downs in summer.

A single Hemp Agrimony bush on the southern steps to the lower slopes hosted 3+ Red Admirals, 3+ Small Tortoiseshells, 2+ Peacocks, 2+ Green-Veined Whites, 2+ Meadow Browns and 2+ Gatekeepers all at the same time.

Hemp Agrimony

The full one acre transect on the lower slopes recorded 69 male Chalkhill Blues, the first of the second brood Adonis Blues, at least three immigrant Clouded Yellows, an estimated 150 Meadow Browns, an estimated 60+ Gatekeepers, six Wall Browns, a counted 19+ Common Blues, 5+ Small Heaths, one Brimstone, about a dozen white butterflies including Large Whites, five Marbled Whites, and 6-spotted Burnet Moths. There were more butterflies over the slopes and I eventually found just one female Chalkhill Blue.

The scrub at the north end of Mill Hill Nature Reserve added 3+ Speckled Wood Butterflies and a Holly Blue.
On the triangle are of the middle slopes a Robber Fly, Machimus atricapillus, landed on a mating pair of Common Blues, which were frequently seen amongst the Marjoram, with more Gatekeepers and Meadow Browns and another Wall Brown. The top meadow added my first Small Skipper with more Common Blues, Gatekeepers, Meadow Browns, Green-Veined Whites and a fresh Small Tortoiseshell. On the top plateau there were two male Chalkhill Blues, Common Blues and Meadow Browns.
NB: There did not seem to be plentiful nectar flowers for the restless lower slope butterflies on an overcast day, the Carline Thistle had only one flower seen, Wild Basil was not as abundant as usual, Dwarf Thistle was popular for brief visits as was the small numbers of Hardheads (Lesser Knapweed), and Bramble was visited by Meadow Browns. I noted Fleabane on the southern steps. Ploughman's Spikenard was beginning to flower and a few more Round-headed Rampion and Autumn Gentian.

25 July 2014
My afternoon visit to Mill Hill was interrupted by a thunderstorm and rain deluge that drenched me to the skin.  I did not complete the acre transect.

 Marbled White
Perforate St. John's Wort
 Autumn Gentian
 Yellow Worts

The southern top part of Mill Hill hosted at least five Small Skippers, a Wall Brown, a Red Admiral, frequent Meadow Browns, a Small Tortoiseshell, a Silver Y Moth and 6-spotted Burnet Moths. There was a bright flash of blue which was possible Adonis Blue which could not be confirmed and more likely to have been a Common Blue.
The lower slopes of Mill Hill, two-thirds of the acre transect, in 15 minutes, before the rain deluge, hosted just 15 (12 + 3) Chalkhill Blues, an estimated 60+ Meadow Browns, frequent 15+ Gatekeepers, three Wall Browns, counted 16 Marbled Whites, occasional Large Whites, at least one Small White, another Small Tortoiseshell, at least one Common Blue, three Small Heaths, and a few pyralid micro-moths Pyrausta despicata.
The first Autumn Gentian in flower this year was spotted on the lower slopes. As it was afternoon the Yellow Wort flowers were closed but these may be coming ot their end. There were hundreds of this tall narrow plant spread evenly over the steeper slopes, more than I had seen before. The first Carline Thistle was budding and there were still a few dead grey thistle plants from the previous year around.

21 July 2014
After the thunder and rain deluges (a weather front from the south), I was curious to see what life was out on the downs and about in the humid sunshine on an overcast muggy afternoon.

 Dark Green Fritillary
 Wall Brown
Dingy Skipper

Dingy Skipper on Blackberries

Large White Butterflies and at least half a dozen Speckled Woods were seen a top of Chanctonbury Drive on the south-west side of the bridge over the A27 to Mill Hill. Butterflies were seen immediately on entering Mill Hill Nature Reserve from the south, by the cattle grid and gate. Four species were seen in a few seconds, occasional Gatekeepers, frequent Meadow Browns. a few Marbled Whites and two skippers, which turned out to be Small Skippers after waiting five minutes for them to briefly settle. There was a second flux of butterfly varieties going down the steps to the lower slopes with the ubiquitous Gatekeepers and Meadow Browns, more of the plentiful Marbled Whites, and at least two Red Admirals, two Small Tortoiseshells, at least one Peacock Butterfly and a Brimstone Butterfly. That was an encouraging ten species before the lower slopes of Mill Hill, where I immediately spotted a the first of about a hundred male Chalkhill Blues, followed almost simultaneously by the first of the Small Heath Butterflies, frequent 6-spotted Burnet Moths, Gatekeepers and Meadow Browns everywhere, followed by two large brown/orange butterflies which were not identified at first. One conveniently landed nearby and was identified instantly as a Wall Brown. This gave a total species of thirteen in as many minutes. The other butterfly was more elusive but I tracked it down and identified it as a Dark Green Fritillary, my first of the year and a rare occurrence on Mill Hill. I counted 36 male Chalkhill Blues in half of the acre transect. Because of the alarming over growth of Privet, at the northern end of the lower slopes, the whole acre transect estimate (partially counted) was only fifty. However, as I retraced my steps to go home far more blue butterflies appeared by about twice as many and they included my first female of the year. Gatekeepers and Meadow Browns were just as numerous and I estimate there were over 30 Marbled Whites. I spotted at least three fresh male Common Blues, two first of the year restless patrolling immigrant Clouded Yellows, more Large Whites, a few more Brimstones and frequent 6-spotted Burnet Moths all on the lower slopes.

My first of year teneral Common Darter (dragonfly) landed in front of me. Lindsay Morris spotted a second brood Dingy Skipper which I managed to spot. Earlier he had seen a Small Copper, but this species eluded me. As I was about to go home I spotted a blue Southern Hawker patrolling the unruly hedge at the bottom of the lower slopes. This is a powerful dragonfly that regularly catches and consumes butterflies.
A small Round-headed Rampion was spotted on the lower slopes. All the Yellow Wort had their flowers closed. Hemp Agrimony on the southern steps attracted two Red Admirals, a Gatekeeper and a Peacock Butterfly all at the same time, and a Brimstone earlier.: There did not seem all that many flowers that the restless male Chalkhill Blues were interested in and they would not stop. They were seen to land briefly on Self-heal. The 6-spotted Burnet Moths were seen almost exclusively on Greater Knapweed.
I only visited the southern half of Mill Hill and the lower slopes.
Adur Butterflies: First Dates

13 July 2014

 Marbled White
Stemless Thistle
 6-spotted Burnet Moths
 Lower Slopes
 Marbled White
Greater Knapweed

A cloudy breezy day after overnight rain is not a prime time to visit Mill Hill. The lower slopes were overgrown with Privet and this was noted by a passing visitor. Purple flowers of the Greater Knapweed and Stemless Thistle were the main attraction for the frequent Marbled White Butterflies the most prominent if not the most numerous butterfly on the lower slopes. The one acre transect count recorded 22 Marbled Whites and only five restless male Chalkhill Blues. The most prevalent butterfly were the Gatekeepers in the scrub with an estimate of exceeding fifty on the transect acre with Meadow Browns  everywhere with twenty plus per acre with three Small Tortoiseshells, one Small Heath Butterfly and on the southern steps at least one Speckled Wood. About ten 6-spotted Burnet Moths were seen by looking at the Greater Knapweed, and if I looked more diligently, I am sure I would have found many more. Grasshoppers hopped over the lower slopes.

7 July 2014
After the paucity of butterflies that often occurs in late June, there were fresh butterflies on the wing were very frequently seen on the downs with Marbled Whites leading the way with at least 71 seen, but there were as many of both Meadow Browns and Gatekeepers of the ten species seen in an hour. On the lower slopes of Mill Hill I recorded 33 Marbled Whites before I nearly stumbled into the first of eight male Chalkhill Blues. Other butterflies seen in ones or twos were Comma, Small Tortoiseshell, Small Heath, Speckled Wood, Red Admiral and a Large White. Burnet Moths had just appeared and there was small pyralid moth Pyrausta purpuralis.
Adur Butterflies: First Dates

 Small Heath
 Small Tortoiseshell
 Marbled White
Greater Knapweed
 Cinnabar Moth

As we have passed mid-summer, many more chalkhill herbs were beginning to flower, notably Hawkbits, Yellow Wort, Centaury, Greater Knapweed.  Musk Thistle, Small Scabious, Field Scabious, Marjoram, but only the first of Stemless Thistle, Wild Basil, Great Mullein and one budding Round-headed Rampion. Autumn Gentian appeared above the short turf but it was not yet flowering.

 Field Grasshopper
 Field Grasshopper

Chorthippus brunneus

19 June 2014
On a hazy day I made an unplanned trip to Mill Hill and on the New Erringham pasture on the north-west side of the bridge, the first of a handful of Small Heath Butterflies were seen amongst the swathes of Bird's Foot Trefoil. The first of the year of at least twenty Marbled Whites were seen on the steps down to the lower slopes. The lower slopes were covered in the white flowers of a massive invasive growth of Privet bushes, with the white of Dropwort and Eyebright.
 Eyebright & Bird's Foot Trefoil 
 Privet on the lower slopes
 Marbled White on Privet

I only walked less than a half transect because as soon as I reached the half-way point I was inundated with Marbled Whites rising from the long grass as I disturbed them. The was also two worn Common Blues. My spell on Mill Hill was much briefer than normal and I departed in less than an hour.
Adur Butterflies: First Dates
Adur Butterfly Report

9 June 2014
On the lower slopes of Mill Hill, I spotted my first Large Skipper and first Meadow Brown Butterfly of the year. The beginning of June is often devoid of butterflies and apart from a dozen Brimstones, about eight Common Blues on the lower slopes, half a dozen Small Heaths  and that was the lot seen around midday. On the middle slopes there was another very white Brimstone and my second Meadow Brown, and on the top of hill another Common Blue. South of the Reservoir I spotted my first two Cinnabar Moths of the year. There were no Adonis Blues seen.

 Common Blue 
 Small Heath
 Large Skipper
 Cinnabar Moth

The bulk of the Horseshoe Vetch, Hippocrepis comosa, had disappeared but there were still isolated flowers as well as a frequent Dog Violets. Privet, Dogwood, Wild Thyme, Yellow Wort and Dropwort were flowering. The first two are invasive of the butterfly sites. I also noted a solitary Self-heal in the short vegetation. Bladder Campion and White Campion were easily spottedon the middle and upper slopes respectively.
Adur Butterflies: First Dates

25 May 2014
Even allowing that I missed a week through rainfall during the week and missed the peak flowering, the swathes of Horseshoe Vetch, Hippocrepis comosa, on the lower slopes of Mill Hill, were very disappointing and only a mere fraction (say 20%) of their luxurious best in good years and not even half as good as bad years.

 Fairy Flax
 Small Purple-barred Moth
 Green Hairstreak

It was breezy and cloudy and far from ideal afternoon for butterflies. In the transect acre I recorded one Red Admiral, 21 (15 +6) Adonis Blues, at least one and probably a pair of Common Blues, about nine Brimstone Butterflies of both genders, my first Small Heath of the year, and one Green Hairstreak landed on a Horseshoe Vetch flower. A Small Purple-barred Moth Phytometra viridaria was seen amongst the short vegetation. As I returned by the pathway the actual number of Adonis Blues seen in an hour was about forty. I had a sortie over the top part of Mill Hill but was late in the afternoon by then and there were no positive butterflies, although there were two possible Dingy Skippers. On the top plateau and middle slopes, the Horseshoe Vetch was less than optimum. Dog Violets were still commonly in flower. The tiny Fairy Flax was now flowering and the first signs of Dropwort was apparent with an occasional plant in flower.
Adur Butterflies: First Dates

15 May 2014
Yellow swathes of Horseshoe Vetch, Hippocrepis comosa, were all over the lower slopes of Mill Hill, especially the steeper slopes. The expanse was far from its peak and in each continuing year the flowers seem to be less and the Privet much greater. After the torrential rain of the previous two days, the butterfly population seem to have been less than normal. The first butterfly spotted was a male Common Blue in amongst the Tor Grass, followed by a restless Peacock. The first of nine (three in transect acre) Brimstone Butterflies patrolled the straggly hedgerow with plentiful Hawthorn in flower. In the early afternoon the first of 16 male Adonis Blues (9 on transect) fluttered around in the weak sunshine.

Wild Mignonette
Common Blue
 Adonis Blue

Single Dingy Skippers advertised their presence but they did seem inclined to rest for more than a few seconds. About a dozen were spotted (8 on transect). I was surprised to notice a Green Hairstreak on the short sward flora landing on a Milkwort. On the steeper part of the lower slopes, I noted an an extremely worn Small Tortoiseshell. The micro-moth Vine Moth, Eupoecilia ambiguella, was spotted on the lower slopes of Mill Hill.

5 May 2014

On the cropped pastures of New Erringham (immediately to the east of Mill Hill) a Red Fox was spotted digging at the turf and then spotted trotting away with a slight limp as a handful of Rabbits scuttled into cover.

 Deadly Nightshade
 Dingy Skipper
Adonis Blue

On a hazy slightly humid day, I was surprised by the fluttering of a pale blue butterfly. When it settled on the abundant Horseshoe Vetch, Hippocrepis comosa, on the lower slopes of Mill Hill, I was able to identify it as my first male Common Blue of the year. Less than a minute later another blue butterfly appeared at the northern end of the lower slopes and this settled as well and I could see it was my first male Adonis Blue of the year. Later I was to spot a female Common Blue and another male Adonis Blue. Other butterflies were only occasionally seen with about eight Dingy Skippers, four Brimstones, at least one Small White and a Wall Brown on the lower part of Mill Hill. A Long-tailed Tit was notable over a clump of thorn and it may have a nest nearby. Hawthorn was in blossom. Dog Violets were still in flower but there were coming to their end. A new violet had appeared with blunt sepals and a purple spur: a few were in flower and others were just budding. The leaves were plain and without hairs. As Sweet Violets had ceased, these were not thought to be them. They could either be a hybrid, an accidentally introduced cultivated stock or may be Hairy Violets?
The records show this was my earliest ever record for a Common Blue. These were probably the first records in England of the Adonis Blue for this year.
Adur Butterflies: First Dates
Butterfly Report

30 April 2014
My transect at Mill Hill recorded 3 Green Hairstreaks, 12 Dingy Skippers and one each of Grizzled Skipper, Orange-tip, Peacock and Brimstone. I twice saw an orange butterfly rush by which did not look like a Comma. (NB: Probably a Wall Brown AH)

Report by Colin Knight on Sussex Butterflies
27 April 2014
An overcast and breezy Mill Hill was alive to the song of birds. I am not sure of the species, as I looked up towards the sound, two Swallows, my first of the year, swooped low over the Blackthorn (which had ceased flowering) on the southern upper part of Mill Hill. It was muddy with small patches of standing water south of the Reservoir.
 Dingy Skipper
 Violet Cosmet Moth
 Bulbous Buttercup
Horseshoe Vetch 

The lower slopes were more sheltered but it was too cold for butterflies and the only species actively fluttering around was a Small White. I did manage to disturb a few butterflies which were quickly blown about in the breeze. There were at least a dozen Dingy Skippers, at least three Grizzled Skippers, one Wall Brown and a Peacock. A Small Purple-barred Moth Phytometra viridaria was seen amongst the short vegetation, with three Pyrausta nigrata pyralid moths and my first Treble-bar Moth of the year.
Horseshoe Vetch, Hippocrepis comosa, were showing but they had only just started flowering and there was scarcely any more flowers than four days earlier.
I spotted a micro-moth Violet Cosmet Moth, Pancalia leuwenhoekella, looking tiny on a Bulbous Buttercup on the middle slopes.
On the top of the hill, I felt a chill in the breeze (Force 5), and I hurried across the plateau at the top where there was only a fresh Wall Brown blown about.
Adur Butterfly & Moth Report

23 April 2014

Horseshoe Vetch
 Pyrausta purpuralis
 Brimstone Butterfly
 Dingy Skipper

A walk around the lower slopes of Mill Hill with a few rays of sun piercing the clouds produced occasional Brimstone Butterflies seen instantly, patrolling the bottom (west side) hedgerow and visiting Cowslips. The sun went in before I saw any skippers. There were a handful of both Grizzled Skippers and Dingy Skippers. I struggled around the transect (under the handicap of a bad cold) noting a flighty Wall Brown, at least one Peacock Butterfly and a Small Tortoiseshell. I failed to locate a reported Green Hairstreak. Three small pyralid moths were noted. Two were Pyrausta despicata and the other one a Pyrausta purpuralis. A Small Purple-barred Moth Phytometra viridaria was seen amongst the short vegetation.
The first hundreds of flowers of Horseshoe Vetch, Hippocrepis comosa, were showing but they had only just started flowering. Dog Violets were still in flower but there were coming to their end.
Adur Butterfly Report
Adur Butterflies: First Dates

17 April 2014
A Dung Beetle possibly Aphodius fimetarius was discovered on Mill Hill.

Report & Image by Su Reed
Adur Terrestrial Beetles

16 April 2014
Against the backdrop of a clear blue sky, a Buzzard soared over the New Erringham pastures on the other side of the country road to the east of Mill Hill Nature Reserve. Rabbits scampered into cover by the hedgerows next to the road. On the lower slopes of Mill Hill, the first dozen or flowers of Horseshoe Vetch, Hippocrepis comosa, were showing along with the the first flowers of Milkwort. Dog Violets were still in flower but the Sweet Violets were down to a occasional battered remnants.

 Horseshoe Vetch
 Dingy Skipper
 Grizzled Skipper
 Green Hairstreak

A Peacock Butterfly, then first of just a few, was first to show over the lower slopes of Mill Hill, where I spotted my first skippers of the year. The first of half a dozen Grizzled Skippers visited violets, followed by three pairs of courting Dingy Skippers. The best discovery was a Green Hairstreak flitting around the Brambles. Pyralid moths were represented by occasional Pyrausta nigrata and at least one Pyrausta purpuralis. A day-flying Small Purple-barred Moth Phytometra viridaria was seen amongst the short vegetation.
Adur Butterfly Report

10 April 2014
A trip to Mill Hill in the afternoon (3:30 pm) sunshine was rewarded with the sight of a Stoat slinking along a footpath, (north of the Reservoir) on the upper part of the hill, with a young Rabbit in its mouth. I only got a quick but clear look of about three seconds, but the Stoat looked like it had a white stripe down its length, but I think this was just its white underbelly. The small size of its prey made me think it was only a young Rabbit.

The lower slopes were alive with butterflies but they were mostly about half a dozen energetic Peacock Butterflies, and about the same number of Brimstones. With energy sapped by a virus I did not search in earnest but I could not find any skippers, and it was only after over thirty minutes that I spotted my first micro-moth Violet Cosmet Moth, Pancalia leuwenhoekella, looking tiny on a Common Daisy. It took my eye a little while to tune in before I was able to recognise at least three Pyrausta nigrata pyralid moths. Only when returning up the steps at the southern end did I spot my first Small Tortoiseshell of the day. Common Bee-flies visited the violets.
Lindsey Morris reported both Grizzled Skippers and Dingy Skippers before I arrived. David Potter also saw them and a Green Hairstreak as well.
Dog Violets were abundant over the lower slopes of Mill Hill with Sweet Violets reduced in numbers and battered by the recent rain. No Horseshoe Vetchflowers were seen.
Butterfly Report
Adur Butterflies: First Dates

1 April 2014
I completed my first transect of the year at Mill Hill: Brimstone 6, Comma 1, Peacock 6, Small Tortoiseshell 1. A Pyrausta nigrata pyralid moth landed in front of me during the survey.

Report by Colin Knight on Sussex Butterflies
I saw my first Grizzled Skipper of the year at 10.30 am on the lower slopes of Mill Hill at Shoreham.
Report by Neil Hulme on Sussex Butterflies

31 March 2014

 Dog Violets
Dog Violets
 Sweet Violets

Dog Violets were now abundant over the lower slopes of Mill Hill with Sweet Violets still abundant as well. Blackthorn was flowering. A single Peacock Butterfly fluttered over the top op the southern part of Mill Hill.
Adur Violets

13 March 2014

 Easter Fox Spider
Alopecosa barbipes
 Sweet Violets
Carline Thistle 

I took advantage of an hour of weak sunshine before the sea fret (=fog) rolled in. I spotted my first large patches of Lesser Celandine at the north end of Mill Hill Drive. Thousands of Sweet Violets were sprinkled over the lower slopes. The hill was visited by occasional Queen Buff-tailed Bumblebees.  On the lower slopes of Mill Hill, I recorded my very first Easter Fox Spider, Alopecosa barbipesI spotted it crawling over the short vegetation amongst the violets.

Spider ID by Keith Lugg  facebook
Adur Weather Report
Adur Violets
Adur Spiders
Previous Spider Record
 Red Admiral
 Small Tortoiseshell
 Peacock Butterfly

Three butterflies made an appearance on and around Mill Hill. All had awakened from diapause(=hibernation) and the first one seen was a Red Admiral (at Chanctonbury Drive, SE of the bridge to Mill Hill) followed by a Small Tortoiseshell  and a Peacock Butterfly.
Adur Butterfly List 2014

Mill Hill Wildlife Reports 2015 (Link)

Mill Hill Wildlife Reports 2013 (Link)
Mill Hill Wildlife Reports 2012 (Link)
Mill Hill Wildlife Reports 2011 (Link)

Adur Valley & Downs on facebook

Identification of Grasses (Link)
Mill Hill Grasses


(Estimated numbers for Mill Hill Nature Reserve only are in brackets)

Chalkhill Blue (3000 +)
Adonis Blue (50 -100)
Dingy Skipper  (75)
Small Heath (250)
Wall Brown  (12)
Meadow Brown  (300)
Marbled White  (50)
Gatekeeper    (200)
Speckled Wood  (>50)
Green-veined White (2+)
Common Blue  (>4000+)
Small Blue       (5)
Brimstone        (8)
Small Skipper   (>50)
Large Skipper   (10+)
Grizzled Skipper  (20)
Brown Argus   (>30)
Green Hairstreak ( a few)

The other species may breed on Mill Hill, but there main breeding area will be adjoining fields or slightly further away. e.g. Small Blue (included above), Small Copper, Small Tortoiseshell, Green-veined White, Peacock, Ringlet, Small White, Large White, Comma, Holly Blue, Orange Tip. (=10)

The following are immigrants &/or hibernators:  Red Admiral, Painted Lady, Clouded Yellow.

The following have not been positively identified (because of ID difficulties):  Essex Skipper. This species is now included for a local field on the Adur Levels within 500 metres of Mill Hill.


The following was confirmed only in 2009: Green Hairstreak.

The next one is no longer found on Mill Hill but were there in the recent (reduced drastically to almost extinct by 1948 last record in  1968) past: Dark Green Fritillary (Records of this butterfly in 1857, 1938, and 1945 when it was common. Now 2014.)
The next one is no longer found on Mill Hill but were there in the distant (1947) past: Grayling.
The next one has been recorded near Mill Hill in the middle distance past:  White-letter Hairstreak


The Silver-spotted Skipper does not appear to ever have occurred on Mill Hill
The Silver-studded Blue has never been recorded from Mill Hill

The Short-tailed Blue was recorded as a single immigrant in 1956.

17 August 2009
A possible (unconfirmed) Brown Hairstreak Butterfly was spotted. A confirmed one was spotted nearby.

There is also the possibility of one of the Fritillary butterflies.

Adur Butterfly Page


History of Mill Hill

Aerial Map
Lower Adur Levels (MultiMap) including Lancing Clump and Mill Hill

Horseshoe Vetch, Hippocrepis comosa
First Draft of the Article for the Shoreham Society Newsletter

Link to the Adur 2012 Nature Notes pagesLink to the Adur Nature Notes 2011 web pages

Link to the Adur 2010 Nature Notes pagesLink to the Adur Nature Notes 2009 web pages
Link to the Adur Nature Notes 2008 web pagesLink to the Adur Nature Notes 2007 web pages
Link to Adur Valley Nature Notes 2003Link to the Adur Nature Notes 2004 Index pageLink to Adur Nature Notes 2005  Index pageLink to the Adur Nature Notes 2006 web pages