Sociable Distance and other inspirations

Still the perfect weather helps to relieve the stresses of the lockdown confinement, slightly warmer and less breezy today with a lighter wind from the south instead of the easterly which has been dominating in recent weeks like a hair-dryer set to cool. Interestingly, the easterly breeze we often get, which can last for several days unabated, a bit like the Mistral, always seems to blow at a steady pace and without the blustery nature of the prevailing south-westerlies. This effect is especially felt along the ridge at the top of Mount Pleasant overlooking the waterworks at Poverty Bottom.

Red Admiral and Holly Blue sightings have been growing in number at home in the garden. Large Whites blouse their way across from garden to garden and Small Whites flutter through in decent numbers. Brimstones and Small Tortoiseshells seem scarce, although most of my Brimstones are usually seen abroad north of the downs along Wealden tracks that I'm not visiting so often this year.

The first, anticipated, sight of Cetonia aurata (Rose Chafer) has now been made in the garden, the metallic green elytra being quite conspicuous on the white Choisya blossoms. There were two today on it. It was a treat to see one a few years ago (perhaps less so for gardeners), but they seem to have established themselves so well in our area in recent years that they are a daily occurrence these days. The Choisya itself has spread a fair amount since last year when I thought it was a little stunted. The scent of the flowers is delicious and fills the garden, having taken over from the Daphne as if they had rehearsed it. Amanda wants to cut it back. Not on my watch.

Cetonia aurata - the long anticipated Rose Chafer

I made a couple of bee hotels from baked bean tins for the garden before breakfast. Funny how one expects an instant uptake by bees – I've been hovering expectantly at times throughout the day without noticing any interest. Jack-by-the-hedge was found growing by the pond; I think this is a first record for the garden. Ash leaves are now unfurling on the big tree, some way behind in progress from the expanding palms of sycamore. The ash has a lot of trunks, all with a filigree of climbing ivy. The tree must have been coppiced on several occasions before being left long enough to outgrow the gardener's saw. My moth trap lights it up at night like a feature tree.

Recent nights with the moth trap have seen the first appearance of Green Carpet and only my second ever April record of Coxcomb Prominent, which plays dead in the hand like a flake of wood. Brimstone Moth, Muslin, Angle Shades and Shuttle-shaped Dart are becoming slightly more numerous; Brindled Beauty and the Orthosias are dwindling slowly, but after an above-average season. Overall numbers are quite low, but should begin increasing again soon.

Coxcomb Prominent (Ptilodon capucina)

I did my transect walk at lunchtime today, with the dogs. I had high hopes, which came to little. Of the 52 butterflies seen, 39 were Small White which were loitering with intent around the oilseed rape, with a nice male Orange-tip, two Large Whites, seven Peacock, only a single Small Tortoiseshell,and two Nettle-tap moths making up the numbers on what was otherwise a quiet and disappointing day. The day had a siesta feel to it in the sun and slack winds; perhaps I should do the walk earlier or later?

The daily walk is a valuable distraction and I'd struggle through the lock-down without it, but each day I look across to Castle Hill LNR on the far side of the river valley and miss it more. I've been thinking of different ruses to help justify visiting and I think I've come up with a solution: a grass-roots walking movement designed to encourage people out for guided daily exercise (walks though – none of that pseudo-army boot camp business) at local nature reserves for one hour each day, walking two or more metres apart from the next person. Participants could bring two metre sticks with them, with or without sharpened points, to help keep other folk at bay. I have even come up with a snazzy name for it: Sociable Distance. The name might be better than the idea itself. Potential sticking points include:

• engaging in an activity which might not fall within the spirit of the lock-down restrictions;
• persuading Lewes District Council to consent to the use of the open space for an activity which might not fall within the spirit of the lock-down restrictions;
• persuading my employer to agree to the time off work.
• There are probably more sticking point to discover during this uniquely mendicant time.

Having the idea in the first place suggested to me that even I am beginning to crave social interaction with other humans. The spring moth lull must be getting to me.

Another lockdown-inspired idea occurred to me shortly afterwards, which would involve using pegs and string to mark out 2m squares at open spaces for people to enjoy wildlife whilst social distancing. The World Between us doesn't sound as snappy a title as Sociable Distance, so more work might be required and I am open to suggestions – and any suggestions received would demonstrate that I'm not the only person who reads this blog! A sticking point: would the Council agree to encourage people out to its nature reserves at the moment? I'm not sure I would.

Where the east wind blows - the ridge above Poverty Bottom

Two years of walking the line

The Rookery Hill 'Mill' Barrow - repurposed ancient monument

The straight line from Falaise Road

I am nearing the end of my second year of weekly wildlife surveys along a line of farmed land between Denton and Bishopstone. The idea arose from a route I traced home two years ago this month from The Crouch in Seaford, which I was able to follow along a more or less straight line of footpaths. This path is stair-rod straight between The Crouch and the parish church of St. Andrew in Bishopstone – St. Andrew being the patron saint of fishermen. A little digging revealed that The Crouch in Seaford was once the site of a medieval market. The name ‘Crouch’ is derived from the Latin crux or cross: the market cross. The Crouch is located close to the coast where the course of the river passed by and other adjacent areas of low-lying land hint at the possibility of a harbour through which passed market goods: coastal and continental imports and locally-caught fish, which might have been brought along the similarly named Crooked Lane. The market ceased in 1712, when the former Cinque Port was in decline and the course of the Ouse had shifted further west.

Only at one point along the route through Seaford did I need to deviate from the line: a private house in Stafford Road ironically named The Gatehouse now blocks the way, whereas once, as the name suggests, it didn’t – except perhaps for those who didn’t know the magic word. The Gatehouse is at the top of a steep bank. The notion of history hiding in plain sight utterly compels me. The emergence of this trackway between the medieval market in the old parish of Sutton, close to Steyne Road – the stony place - to the parish church of St. Andrew in Bishopstone, which itself is linked by a nearly straight line to the parish church of St. Leonard in Denton, was a source of great excitement. So I celebrated its rediscovery in the way I know best by dedicating a wildlife survey to its memory!

The true reason for creating the weekly transect survey along this stretch of land was to study the impacts of intensive farming activity upon the insects, and to evaluate the importance of headland flora using butterflies (and moths) as an indicator. How better to do this though than to use ancient trackways that our ancestors used to travel to and from places of worship and commerce? I am using them instead to commune with nature.

I began the inaugural walk during the first week of April 2017 not yet having chosen the exact route; I decided that I would allow the land to decide where I should walk. The original idea that I would record butterflies on a weekly basis between April and October along a straight-lined route quickly evolved into something approaching a narrow ellipse.  At the end of that first walk I had traced a route from the end of Falaise Road in a roughly south-south-easterly direction beyond Foxhole and Stud Farms, as far as the gate at the bottom end of Rookery Hill by the Bishopstone village road, then back uphill beyond four tumuli as far as the kissing gate which separates Rookery Hill from Norton Hill. Incidentally, this kissing gate is situated on the banks of the northern-most tumulus, which was adapted during medieval times to act as the base of a mill. The route takes me along headlands abutting intensively-farmed fields and skirts the edge of improved pastures at Norton Hill and Rookery Hill. The headlands are razed to the ground each summer just prior to the harvest. Norton Hill is a recovering ‘improved grassland’ pasture, which is still moderate in terms of biodiversity, but with no recent fiddling and grazed by a small cattle herd, a flock of sheep and occasional escaped Dartmoor ponies. A mixed sward is slowly establishing itself year on year. Rookery Hill is an ancient landscape, formerly a promontory bounded by the Ouse floodplain on three sides, lately though an un-grazed meadow improved with fine grasses such as fescues and is cut for hay each June, approximately (but not intentionally) in phase with the interregnum between the first and second broods of the Small Heath butterfly. Neither meadow is rich in flora or fauna, but the tumuli act as an archipelago of tiny stable grassland habitats for mixed flora and insects. I have found previously unseen Silver-spotted Skipper and Adonis Blue butterflies in small numbers, as well as a good colony of Small Heath in these pastures. The latter species has been the undisputed monarch of Rookery Hill during the first two years of the survey.

The tumuli are bowl barrows, believed to be 3500 to 4500 years old. This is what Historic England has to say about them:

Bowl barrows, the most numerous form of round barrow, are funerary monuments dating from the Late Neolithic period to the Late Bronze Age, with most examples belonging to the period 2400-1500 BC. They were constructed as earthen or rubble mounds, sometimes ditched, which covered single or multiple burials. There are over 10,000 surviving bowl barrows recorded nationally, and …the bowl barrow on Rookery Hill survives well and … is one of the best examples of this type of monument to be found on the East Sussex Downs. These prehistoric barrows are the earliest known structures on Rookery Hill, and … provide evidence for the continuity of burial, settlement and agriculture in this area of Downland over a period of at least 3000 years.¹

Today I followed the route with Leo and Charlie; they are helpful in flushing up butterflies and especially so the small heaths. It was a warming day, sunny with a light northerly breeze. The sky was grazed by a hundred contrails, suggesting the air was freezing cold at aircraft level. Even after several hours of sunlight, the longer grasses were still soaked with dew and some parts of the route were still in shadow. The diminishing power of the sun is evident in these places. All morning a nauseating hydrocarbon stench – surely the exhaust from Newhaven’s industrial centre? – had been carried downwind by the breeze and it wasn’t until nearly halfway that we’d moved beyond the plume. As I looked back I realised I was wrong: a dark plume of smoke was rising from Denton Wood, somewhere near the stable yard on The Crescent track. The smell was quite disgusting and probably not at all healthy.

Only the hottest patches along the route seemed to have attracted butterflies. The very start was the only part which had any activity during the first half, with the usual flurry of Large and Small Whites blousing their way around the hedges and scrub. These today were joined by a pair of Clouded Yellows and an inaugural record for the transect of Mallow Moth, which I followed for some minutes before it allowed me an approach close enough to gain a positive ID. Plenty of its food-plant lines the headland path. It was quiet otherwise; even the ivy bees nectaring on ivy blossom seemed fewer in number. The lack of Red Admirals was again noticed by their absence. Where I have counted 40 on a particular ivy patch in the past, today I saw none. This is proving to be a poor year for them, possibly because of the hot, dry weather in July.

The path along the field headlands was an insect desert. Birds in the paddocks at Foxhole Farm included a fair flock of Meadow Pipit with a few Pied Wagtails and Linnets intermingled. A Sparrowhawk circled overtly, high above. Occasional buzzards soared lazily on thermals higher still. The final section of the transect route is usually the most active, and so it was today. As Rookery Hill descended towards the floodplain below and tipped the angle of the ground sunwards, beneath the airflow, the additional heat hosted the only Small Heaths seen along the route – a pair close together. It was a day of pairs: two Red Admirals skimmed past with purpose and, by the largest of the four tumuli, a pair of third-brood male Wall Brown were alternately basking on hot dried grass patches and sparring in tight circles before suddenly and violently breaking apart. I lingered for a little while and noted that the pair would spar two or three times each minute. This must be an exhausting activity.

The temperature was rising on the way home to nearly 20°C and this encouraged a few more insects into action: a pair of Silver Y moths and a few more white butterflies. Adult numbers though are settling down for the winter now and there must now only be a few more weeks left in the survey season.

The list:

Large White (Pieris brassicaeI) 13

Small White (Pieris rapae) 3

Clouded Yellow (Colias croceus) 2

Small Heath (Coenonympha pamphilus) 2

Wall (Lasiommata megera) 4

Red Admiral (Vanessa atalanta) 2

Mallow Moth (Larentia clavaria) 1

Silver Y (Autographa gamma) 3

Reference

Bowl barrow, the north westernmost barrow of a group of six bowl barrows, forming part of a linear round barrow cemetery on Rookery Hill (online)  https://historicengland.org.uk/listing/the-list/list-entry/1009954 (accessed 05/10/18).

Rookery Hill barrow to Firle Beacon

Hotter microclimes

Mallow Moth (Larentia clavaria)

Ivy blossom

St. Andrews at Bishopstone - a straight line to The Crouch marketplace

Butterflies and moths seen at Newhaven's Castle Hill LNR in mid-July

Week 16 of the 2016 transect-walking season

Rosebay Willowherb

It was my turn again this week to survey Castle Hill LNR for butterflies and moths - and the weather, for the first time this year, was perfect. Good weather allows for a more accurate picture of which species are present at the site and also their relative numbers. I saw a total of 34 species and over a thousand individuals (1013 in total). These included four species which had not previously been recorded at the reserve (one of these - the Dun-bar - flew into my car as I arrived!).

Despite the cliff-bottom slumps being used as a camp site, outdoor latrine, waste disposal area and bonfire and barbeque site, I was pleased to see that our small colony of Crescent Plume moths has survived another year.

If the weather remains good, the next few weeks should produce similar numbers, with Common blue numbers increasing through August. With such an abundance of insects and flowers in bloom, this is the best time of the year to visit the nature reserve. Enjoy it while it lasts!

Here's the list in full:

Moths (18 species)

Six-spot Burnet (Zygaena filipendulae)  72
Ginger Button (Acleris aspersana)  1
Pale Lettuce Bell (Eucosma conterminana)  1
Orange-spot Piercer (Pammene aurana)  1 - first site record
Satin Grass-veneer (Crambus perlella)  1 - first site record
Straw Grass-veneer (Agriphila straminella)  3
Little Grass-veneer (Platytes cerussella)  3
Straw-barred Pearl (Pyrausta despicata) 1
Twin-barred Knot-horn (Homoeosoma sinuella)  1
Crescent Plume (Marasmarcha lunaedactyla)  4
Oak Eggar (Lasiocampa quercus)  1
Shaded Broad-bar (Scotopteryx chenopodiata)  1
Green Pug (Pasiphila rectangulata)  1
Cinnabar (Tyria jacobaeae)  2
Large Yellow Underwing (Noctua pronuba)  1
Dun-bar (Cosmia trapezina)  1 - first site record
Cloaked Minor (Mesoligia furuncula)  1 - first site record
Silver Y (Autographa gamma)  15

Butterflies (16 species)

Essex Skipper (Thymelicus lineola)  55
Small Skipper (Thymelicus sylvestris)  16
Large Skipper (Ochlodes sylvanus)  1
Large White (Pieris brassicae)  17
Small White (Pieris rapae)  69
Green-veined White (Pieris napi)  77
Speckled Wood (Pararge aegeria)  6
Meadow Brown (Maniola jurtina)  129
Gatekeeper (Pyronia tithonus)  200
Marbled White (Melanargia galathea)  292
Red Admiral (Vanessa atalanta)  22
Peacock (Aglais io)  1
Small Tortoiseshell (Aglais urticae)  7
Comma (Polygonia c-album)  5
Small Copper (Lycaena phlaeas)  1
Common Blue (Polyommatus icarus)  4

Wild Carrot (Daucus carota) growing on the cliff-bottom slumps

 

Rough mixed grasses and flowers by Barrow Head

Agrimony reaching up by Barrow Head

Hemp Agrimony on the north slope - an excellent nectar source for butterflies

Buddleia above Bickerstaff's Bend - a good nectar source for moths at twilight

Midsummer and middling at Newhaven's Castle Hill Local Nature Reserve

Week 12 of the transect walking season

We have reached mid-summer and the season at Newhaven's Castle Hill LNR is moving on apace. The clifftops are heading into their peak flowering season: Common Bird's-foot Trefoil, Horseshoe Vetch and Sedum make shining fulvous and citrine splashes of colour on the cliffs and offer nectar to a thousand-and-one pollinating insects. The pollen-eating Swollen-thighed Beetle (Oedemera nobilis) can be found on bramble blossom, oxeye daisy and various umbellifers, the aggressive males bundling rivals off their territories. On the north slope haws are already forming where only weeks ago the trees were adorned in bridal white blossom.

The transect-walking season is also approaching its mid-point and we continue to feel a sense of disappointment that there are not more butterflies on the wing. The weather was not bad during today's walk with unbroken sunlight for the duration, but a fresh breeze was blowing in off the sea, sending most butterflies and moths to ground along the exposed cliffs. June is a mid-point for adult butterflies - the eye in the year's butterfly storm. The June Gap is a time when the first waves of emergent adults have passed over and when their offspring are feeding-up and spinning-up prior to taking to taking wing in the high summer sky. Few adult butterflies are seen during the June Gap.

The Large Skipper is one butterfly which bucks the trend. This is an insect of rough grassy places which feeds as a caterpillar on cock's-foot grass and is present in a single brood from late-May or June through to August. It is a conspicuous, territorial and pugnacious butterfly and it should reach its peak at Castle Hill in the next week or two. Meadow Browns are making a cautious start to their adult season and they will gradually increase over the next month before building towards late-summer abundance. The first brood of Speckled Woods is now declining and, although numbers never completely disappear throughout the season, we will need to wait for about six weeks to see the next spike in numbers. The leafy paths which criss-cross the north slope of the reserve provide the dappled shady habitat which makes this one of the commoner butterfly species here.

A male Cuckoo was seen flying near to the Lookout during the walk, preparing to make its return journey to sub-Saharan Africa. The season really is moving on.


Butterflies (5 species)

Haws

Large Skipper (Ochlodes sylvanus)  8
Speckled Wood (Pararge aegeria)  2
Meadow Brown (Maniola jurtina)  2
Holly Blue (Celastrina argiolus)  1
Common Blue (Polyommatus icarus)  3

Moths (7 species)
Narrow-bordered Five-spot Burnet (Zygaena lonicerae)  1
Common Nettle-tap (Anthophila fabriciana)  1
Diamond-back Moth (Plutella xylostella)  2
Swan-feather Dwarf (Elachista argentella)  1
Common Marble (Celypha lacunana)  2
Garden Grass-veneer (Chrysoteuchia culmella)  1
Cinnabar (Tyria jacobaeae)  1

Common Cuckoo (Cuculus canorus)  1

Large Skipper (Ochlodes sylvanus)

Oedemera nobilis - the Swollen-thighed (leaf) Beetle

The butterflies of Castle Hill Local Nature Reserve, Newhaven

Transect walk 2016 season, week six

Thrift in bloom

After a slow start to the year, this week's transect walk saw a positive increase in activity around the nature reserve with 18 species and 102 individuals seen. A growing number of day-flying moths are active now and take off as you walk along the clifftop and undercliff paths. This includes the migratory moth the Silver Y, which has begun to arrive from continental Europe, aided by the south-easterly winds in recent days. Burnet Companion is always a welcome sight in the herb-rich areas of grassland. Plenty of White butterflies and a Brimstone were also seen above and below the cliffs, especially around the dense patches of Hoary Cress which hug the base of the cliffs, to which the Small White is attracted.

Male Speckled Wood butterflies have now established their territories along the shady paths to the north of the reserve; they swoop up and challenge many who invade their patch of dappled sunlight. A Brown Argus seen near the Lookout is the first reported sighting in Sussex this year and is the earliest it has been recorded at the reserve.

Patches of gorse are alive with the small Grey Gorse Piercer moth, which flies up in tiny swarms when a branch is knocked. Green Hairstreak butterflies, which to the untrained eye are difficult to see in flight, are also active around the gorse and are apparently increasing in number each year. This year has been the best since we started the transect walk six years ago.

During my walk I set out a pheromone lure and attempted to attract male Emperor Moths - a species which has not previously been recorded at Castle Hill LNR. The lure emulates the pheromone which is broadcast by freshly emergent females. I had not used one prior to this year and some were bought by the Friends of Castle Hill to confirm whether this common, yet elusive, stunningly beautiful moth is present. It is! I recorded two males in the area near the pond. This brings the moth and butterfly species list up to 332.

Emperor Moth male

Other insects seen during the walk included a mating pair of the tortoise beetle Cassida nobilis, probably the first time this species has been seen at the reserve. A pair of Stonechats was seen feeding a fledgling juvenile and more were heard deep in the bramble, no doubt preparing to fly the nest. It reminds me that the season is moving on apace.

Grey Gorse Piercer

Here's the full list (18 species, 102 individuals):

Green Long-horn (Adela reaumurella)  10
Common Nettle-tap (Anthophila fabriciana)  1
Brown-spot Flat-body (Agonopterix alstromeriana)  3
Silver Carrot Conch (Aethes williana)  2
Grey Gorse Piercer (Cydia ulicetana)  30
Straw Pearl (Pyrausta despicata)  2
Emperor Moth (Saturnia pavonia) 2 males - new species
Brown-tail (Euproctis chrysorrhoea)  1 larval web
Silver Y (Autographa gamma)  2
Burnet Companion (Euclidia glyphica)  1
Brimstone (Gonepteryx rhamni)  1
Large White (Pieris brassicae)  4
Small White (Pieris rapae)  23
Speckled Wood (Pararge aegeria)  6
Peacock (Aglais io)  5
Small Tortoiseshell (Aglais urticae)  3
Green Hairstreak (Callophrys rubi)  6
Brown Argus (Aricia agestis)  1 - first known Sussex sighting in 2016

The striking hoverfly Helophilus pendulus

April's butterfly and moth sightings

April in Newhaven was a poor month for moths and butterflies. I operated my moth trap on 22 nights out of 30 during the month. Forty four species were recorded; a total of 304 moths and butterflies were seen. 

For comparison, my personal ten year average in April is sixty three species and 619 sightings of individuals. Almost all species in April 2016 were seen in numbers below their ten year average, with the exceptions of Light Brown Apple Moth (Epiphyas postvittana) and Angle Shades (Phlogophora meticulosa), which were both slightly above average but still only seen in low numbers (24 and 10 respectively). Butterflies were also below average in number, with only Peacock (Aglais io) being seen in something approaching good numbers with 58 individuals counted (43 of which were seen in one day at Well Bottom near Tarring Neville).

April saw the start of the 2016 transect-walking season at Newhaven's Castle Hill Local Nature Reserve. This, too, has been slow - the slowest start of all the six years that the walk has been performed.

The highlight of the month was the chance finding of a single Phyllonorycter rajella on the inside of my office window in Lewes on 14th. This appears to have been the first Lewes record since before 1849 and the first adult seen anywhere in Sussex since 1984 - 32 years ago.

Another highlight was a single Acleris cristana form fulvovittana, which was attracted to my garden on the night of 11th.

Species summary, April 2016 (44 species) (all adults unless stated below)

125W Robinson trap at home (29 species)

Case-bearing Clothes Moth (Tinea pellionella)  1
Common Slender (Caloptilia syringella)  1
White-shouldered House Moth (Endrosis sarcitrella)  2
Sulphur Tubic (Esperia sulphurella)  1
Common Flat-body (Agonopterix heracliana)  1
Ruddy Flat-body (Agonopterix subpropinquella)  1
Light Brown Apple Moth (Epiphyas postvittana)  24
Tufted Button (Acleris cristana f. fulvovittana)  1 - new site record
Twenty-plume Moth (Alucita hexadactyla)  1
Narrow-winged Grey (Eudonia angustea)  2
Common Plume (Emmelina monodactyla)  6
Emperor Moth (Saturnia pavonia)  1
Frosted Green (Polyploca ridens)  1
Streamer (Anticlea derivata)  2
Double-striped Pug (Gymnoscelis rufifasciata)  14
Early Thorn (Selenia dentaria)  1
Puss Moth (Cerura vinula)  1
Dark Sword-grass (Agrotis ipsilon)  1
Flame Shoulder (Ochropleura plecta)  1
Small Quaker (Orthosia cruda)  3
Powdered Quaker (Orthosia gracilis)  1
Common Quaker (Orthosia cerasi)  28
Clouded Drab (Orthosia incerta)  5
Hebrew Character (Orthosia gothica)  53
Shuttle-shaped Dart (Agrotis puta)  1
Mullein (Shargacucullia verbasci)  1
Early Grey (Xylocampa areola)  24
Angle Shades (Phlogophora meticulosa)  10
Silver Y (Autographa gamma)  3

Fieldwork (15 species)

New Holm Oak Pigmy (Ectoedemia heringella)  mines on Evergreen (Holm) Oak (Quercus ilex)
Green Long-horn (Adela reaumurella)  1
Garden Midget (Phyllonorycter messaniella) mines on Evergreen (Holm) Oak (Quercus ilex)
Firethorn Leaf Miner (Phyllonorycter leucographella)  0
Common Alder Midget (Phyllonorycter rajella)  1
Fox Moth (Macrothylacia rubi)  2 dead larvae
Green Carpet (Colostygia pectinataria)  1
Common Heath (Ematurga atomaria)  2
Orange-tip (Anthocharis cardamines)  1
Small White (Pieris rapae)  8
Brimstone (Gonepteryx rhamni)  7
Speckled Wood (Pararge aegeria)  7
Peacock (Aglais io) 58
Small Tortoiseshell (Aglais urticae)  21
Holly Blue (Celastrina argiolus)  2

Phyllonorycter rajella (Common Alder Midget)

Esperia sulphurella (Sulphur Midget)

Tufted Button (Acleris cristana f. fulvovittana)

Green Carpet (Colostygia pectinataria) at Well Bottom

Frosted Green (Polyploca ridens

Puss Moth (Cerura vinula)

Early April at Barrow Head

Transect walking season, weeks one and two

It is the second week in April. My good friend David Harris and I have started our annual season of  transect walks around Newhaven's Castle Hill Local Nature Reserve. We will share alternate weeks between now and the end of October, or whichever time of year that there are too few butterflies on the wing to make the walk worthwhile. This is the sixth year that the transect has been walked and it has become a staple of my wildlife year. It is sometimes a tough commitment in high summer, when all the daily demands of life are queuing up impatiently asking for attention, but the transect walk is always a joyous few hours' escape from everything other than what can be seen before you.

David has walked week one; week two is my turn (David odd; Steven even). In week one only a single butterfly was seen: a Small Tortoiseshell (Aglais urticae) on the clifftop at the extreme west of the nature reserve. We have never had a quieter start to the season.

To compensate for the lack of butterflies and moths, David did make an excellent sighting of the Forget-me-not Shieldbug  (Sehirus luctuosus), also along the clifftop but just to the east of the headland known as Barrow Head. This is not a rare insect, but it is not common either and it's a new species added to our site list. It's food-plants (Forget-me-not or Myosotis species within the Borage family) can be found in quite a few places around the reserve and include Early (Myosotis ramosissima) and Field Forget-me-not (M. arvensis), which are just coming into bloom now, as well as the later flowering species Wood (M. sylvatica)  and Changing Forget-me-not (M. discolor). If luck is with you, you might be fortunate enough to see the small black bug crawling on the ground around the plant or perhaps basking on a leaf.

I have just completed the week two walk around Castle Hill. I am out early because the early morning sun is forecast to be replaced with cloud from late morning onwards. I have seen only one butterfly: a Peacock (Aglais io), on the sheltered glade on the north slope of the reserve. Other insects of interest seen included quite a few Dark-edged Bee-flies (Bombylius major) and an extraordinary number of Buff-tailed Bumblebees (Bombus terrestris) - several hundreds or more all basking in the sun, nestled and half enveloped in grass everywhere along the transect route. It is as though all the bees have been placed under a soporific spell.

As I return to my car, which is parked beneath Barrow Head, I am distracted by an attempted robbery: a lone Raven is visiting each of the many Jackdaw-hollows in the chalk along Barrow Head in search of Jackdaw eggs, like a taxman making house-calls. The Jacks are brave and mob the intruder as it moves systematically from one hole to the next. The Raven visits each hollow not with a short hop but with an exaggerated flycatcher-like loop away from the cliff and back again, tracing a teardrop in the air.

These are both Corvid species, but they are the largest and the smallest and the difference in size is startling. Their evolutionary close kin-ship stands for nothing. The Raven goes calmly about its business and appears to be indifferent to the smaller Jacks as they cartwheel through the air, but the hollows are all empty. It seems the Jacks are still nest-building and have not yet laid their clutch. The Raven perches on the ledge of each, looks monstrously within, pauses for a moment and loops back into the air. With all the house-calls made, the Raven moves away penniless in an eastward direction and the drama is over.

A slab of early morning cloud has drifted off to the east and the spring sun warms my back, while a chilly breeze frisks me from the west, chilly enough to usurp any comfort offered by the sun. As the Jackdaws and Feral Pigeons settle, I climb the slump past them and past Barrow Head on its east side towards a flush of golden flowers which have caught my attention and I find myself suddenly out of the influence of the breeze. Here, it is another day; a hot, calm morning in summer. The heat of the sunlight uninhibited by the breeze is astonishing.

Water-pepper - I think

The flower is Lesser Celandine (Ranunculus ficaria). The starburst flowers open only in sunlight, forming a mirror-mat of gold amidst a nest of heart-shaped green glossy leaves. It is a welcome sight, doubly so because they are the first I have seen on the ground we cleared a few weeks before when we were cutting brambles. It might have grown amongst the thorns in previous years, but it could be a pioneer. This flower, for all its early season beauty, is actually an invasive pest which is blooming amongst the grass in most areas across the reserve. A few steps away is a seasonal pool with what appears to be leaves of Water-pepper (Persicaria hydropiper) reaching up above the surface. It is a plant of winter-wet places. In summer its tresses of pink flowers droop in sorrow towards the parched ground.

Lesser Celandine (Ranunculus ficaria) - growing where recently bramble dominated

As I descend away from the splash of gold and skirt along the base of the cliff a movement to the right catches my eye and I see a basking Adder (Vipera berus) slide towards a clump of long grass with a small hole at its side. As I slowly crouch towards it and rest stone-still, the snake pauses and I am granted a view of the black arrowhead behind its red eyes.

Adders emerge from their underground hibernacula - often a mouse-hole they entered in October-time - at any time from late March or when daytime temperatures climb into double figures. Early mornings and late afternoons are the best times to search for them, when they bask in a sheltered spot, such as this, flattening their bodies against the warm earth, soaking up the sun's energy. This is an essential habit which aids hunting and digestion, especially early and late in the season. The immature male Adder before me will spend the next few weeks feeding mainly on mice or small reptiles such as lizards and slow worms. He'll take all the sun he can find.

This Adder might be the same individual we observed last year. He is not fully grown and I estimate that he is somewhere between two and three years old. Maturity is not reached until four or five years. Adders are fairly slow-growing snakes. He is possibly not mature enough to engage in the violent mating rite sometimes called the dance of the adders, which occurs in April or May. This is a wrestling match fought between males, in which no use of the fangs is made, and in which the winner may mate entwined with a female in a tangle with up to several other males.

Vipera berus - a basking female Adder

Adders are not the indiscriminate biters that some people hold them to be. They are misunderstood and vulnerable, unnecessarily persecuted by humans and predated upon by a number of animals including hedgehogs, birds of prey and crows - including the Jackdaws around the corner of this headland. Their venom is precious to them and they bite only if they are forced to defend. I have given this snake no reason to be fearful and he has paused and rewarded my cautious approach with the gift of a close observation. I back away and leave him to the sun.

The Jackdaws wheel and chatter above me and I return to my car, leaving the birds, bees, Adders and flowers to enjoy the sheltered sunlight.