Lesser Redpolls at the Brickworks

It was another seriously mild (14 to 15°C) December day with only a slight breeze. The mud at the Brickworks is marginally less squelchy. I think we’ll need a week of dry weather before that’ll harden over. Anyway, a brief post just to note the presence of a couple of Lesser Redpolls on site today. I don’t know how frequently this species is seen across Trust land but this was my first record of them in the 2.5 years I’ve been exploring the wildlife around the Box Moor Trust. Close by was a Long-tailed Tit flock mixed with other Tits and Goldcrests and I do wonder if the two Redpolls had been drawn along with them. Anyway, birds of note this afternoon:

2 Lesser Redpoll
12 Long-tailed Tit
6+ Goldcrest
7+ Wren (2 singing, others swapping alarm calls “teck, teck, teck”)
17 Fieldfare flying over, heading west
8 Bullfinches
25+ Goldfinch
Mix of Chaffinches, Great Tits and Blue Tits
A couple of singing Robins plus others around site, along with Dunnocks
2 Jay
2 Green Woodpeckers
1 Kestrel
Plenty of Blackbirds & Magpies & Woodpigeons around the site

Burrowing creatures

The weekend doesn’t seem to have incorporated a great deal of daylight. Darkness, yes. Drizzle, yes. Rain, yes. And, at the Brickworks, mud. Mud, mud and more mud.

Views of the mud and murk at Bovingdon Brickworks today

As I walked through the mudow (that’s mud/meadow) (top left photo), a Song Thrush was singing in the trees to my right. A crystal clear, full-bodied melody of flutes and whistles, projected far and wide. It was better than sunshine. Up ahead of me, I spotted another 5 Song Thrushes together in a bush and, behind me, 2 more. There were at least 10 around the site. A flock of 40+ Goldfinches were feeding on thistle seeds, along with Chaffinches and a mix of Tits. Last week, I’d counted at least 20 Blackbirds within the scrub and, easily, 5 Green Woodpeckers. 3 Jays gave me glimpses of white rumps and a couple of Fieldfare swapped one tree for another. Towards the end of my squelching, I chanced upon a Robin quietly singing his pretty sub-song. It was as though he was testing the air to see if anyone was listening. Delicate yet sure and another ray of sunshine.

The main reason for my visit today was to retrieve the trail camera, which I’d set up over night. We were keen to discover what had created the two burrows found by David K a few weeks back. The entrance holes are approx 40-45mm diameter and excavated soil is piled up outside like a larva flow.

The camera trap results weren’t bad. I’ve put together 60 seconds worth from the 120+, 14 second clips that were captured. All occurred between 21:00 and 00:00 yesterday. I’d put down a few peanuts and sunflower hearts to entice little creatures to do more than dash, dart and streak across screen.



So, the mystery homemaker is definitely a mouse and we have at least 2 living in this burrow. They’re likely Wood Mice (Apodemus sylvaticus) but I think only daytime footage would clinch it (fur colour). I confess, I had hoped for Bank Voles but, even so, it’s been useful to get some experience with the trail camera and learn more about the habits of these little Wood Mice.

Winter mixed Tit flocks

I’m still keeping my eyes and ears peeled for a Yellow-browed Warbler or Firecrest at the Brickworks. No luck today but I did come across an impressive mixed Tit flock containing the following:

9+ Goldrests
11+ Long-tailed Tits
3 Blue Tits
2 Great Tits
4 Chaffinch

Around the rest of the site, I encountered another small flock of Long-tailed Tits and further Tit and Finch flocks. Total minimum counts for the morning were:

9+ Goldrests
15+ Long-tailed Tits
6+ Blue Tits
5+ Great Tits
8+ Chaffinch
8+ Bullfinch
20+ Goldfinch
1 Skylark (flyover)
1 Nuthatch
6+ Robins
4+ Dunnocks
8+ Blackbird
15+ Redwing
1 Jay
2 Green Woodpecker
8 Magpie
1 Kestrel
1 Red Kite
+ Woodpigeons & Carrion Crows

It was unusual not to see one of the 3 resident Buzzards riding the thermals with the Red Kite. Also, after what feels like weeks of Siskin passage, with single birds flying over during recent visits, I didn't hear one this morning. A good sized Redwing flock (50+) arrived last week (20/10/2015) and there are likely more around than the 15 or so seen/heard.

P.S. The Common Toadflax is still flowering and still a very cheery sight.

Autumn blooms!

It may well be a common plant of “waste grounds, grasslands, roadside verges and hedgerows”, but it’s one of the few that produces cheerful, sunny blooms right through to the end of November. As many flowers are finishing and the leaves are turning and falling from the trees, Common Toadflax (Linaria vulgaris) bursts into life. There are a good number of plants in the scrub ground east of Baker’s Wood. If you’re in need of autumn and even winter cheer, head on over for a closer look.

Young birds

11 Brassy Longhorns (Nemophora metallica) were still on the Field Scabious at the Brickworks on Thursday. A couple of 6 Spot Burnets were also on Field Scabious and there were plenty of butterflies and other insects around the site.

Thursday seemed to be a popular fledging or exploring day as I came across noisy families of Bullfinches, Blue Tits, Robins, Whitethroats and Linnets. A pair of Red Kites was displaying overhead and a young Green Woodpecker was exchanging contact calls with its parent.

Brassy Longhorns, 6 Spots & a Painted Lady

It was a blustery but sunny morning last Friday. I was out looking for Purple Hairstreaks but actually came across a cloud of glistening micro moths. These turned out to be Brassy Longhorns (Nemophora metallica), a county rarity. They favour Field Scabious and are on the wing during June and July. This is the forth species of day-flying longhorn moth that I've come across on Trust land. The other three are:

• Fairy Longhorn (Nemophora degeerella)
• Green Longhorn (Adela reaumurella)
• Little Longhorn (Adela (Cauchas) fibulella)

Brassy Longhorn on Field Scabious

A couple of 6-Spot Burnets were also lovely to see and another faded Painted Lady.

Butterflies, Moths & Dragonflies

Over the last few weeks the Small Skippers and Gatekeepers have emerged at the Brickworks. Still plenty of Meadow Browns, Ringlets and Marbled Whites on the wing. Red Admiral, Small Tortoiseshell, Comma, Large Skipper and Peacock all still around and a handful of Speckled Woods looking a little worn now.

Peacock butterfly larva on nettle

Gatekeeper, male

Southern Hawker, female

I came across a new-to-me moth this week, called The Snout (Hypena proboscidalis). What a great name, especially when you see what inspired it. This moth has two long mouth parts also known as palps (sensory organs used for 'tasting' nectar sources). They stick out like an upturned nose. Many moths have palps but none so exaggerated as in the Snout.

The Snout (Hypena proboscidalis), not the best photo but the best I could get before it flew off!

A Night with the Moths

Ben Sale and the Trust mothing team were up into the small hours on Wednesday night, trapping at the Brickworks. For the full report and a selection of great photos, see Ben's blog HERE.

Lesser Whitethroat, Ringlets & Bee Orchid

I had a very nice surprise yesterday, when a male Lesser Whitethroat popped up at the Brickworks, singing from scrub at the SW end of the site. It’s not an easy species to see or find locally, making it all the sweeter to experience. This isn’t the first record for the Brickworks though. Roger Prue found a singing bird on 2nd May 2013 in the field adjacent to Green Lane. Anyway, I recorded it’s vocal and hoped that when I returned in the afternoon I might be able to get some video footage. Unfortunately, it had either shut up, or flown off, and it wasn’t there this morning either.



On Wednesday, the Dacorum U3A Wildflower Group visited the Brickworks and let the Trust know that they’d found a Bee Orchid (Ophrys apifera) “in the field adjacent to Green Lane”. Great news and well spotted! I know Martin Parr came across 5 spikes at TL007028 last year, which is in a different area, so, it’s great to hear of another occurrence of this charismatic little orchid.

Ringlet (Aphantopus hyperantus)

This week, amongst the fresh Marbled Whites, there have also been a handful of newly emerged Ringlets and Small Skippers. I also had my first Damselfly at the site, a female Azure. And, having had a female Broad-bodied Chaser earlier this month, it was lovely to see a Southern Hawker dragonfly checking out the Buddleja bush by the entrance gate, on Monday.

Not the best photo but the colours are incredible on the Common Purple & Gold (Pyrausta purpuralis)

A few nice moths this week: Cinnabar, Burnet Companions, a vibrant Common Purple & Gold  and 2 Triple-stripe Piercers (Grapholita compositella). I first came across the Triple-stripe Piercer species with Martin Parr on 13 May, whilst we were looking for Cranesbill plants. This week, I was able to watch it in action. The moth would land on large bramble leaves and then rapidly spin round in a circle, with its head at the centre, as if playing Spin The Bottle. It was very odd and I can only assume that this process allowed the moth to pierce the leaf to feed on the juices? As for the larvae, they feed on Clover (Trifolium) species, where eggs are deposited singularly on leaves.

These 3 semi-out-of-focus shots don't do this little 10mm moth justice. Up close, it's smart!

Triple-stripe Piercer (Grapholita compositella)

Wild Strawberries & Pygmy Shrews

Just a quick post to note the presence of a wonderful stretch of Wild Strawberries (Fragaria vesca) at the Brickworks (grid ref: TL007027). The species isn’t listed on the 2011 plant survey so must be a fairly recent colonisation. Fantastic to see!

Also, I picked up a couple of dead Pygmy Shrews (Sorex minutus) from the path but at different locations.

Both shrews were identical in their measurement:
Body = 65mm
Tail = 40mm
Tail relative to body = 61%

Migrants & Fledglings

A circuit of the Brickworks today produced the following butterflies and moths, including the first migrant butterfly of the year and some lovely fledglings.

Bovingdon Brickworks (TL008027 & surrounding area)
4 Speckled Wood
16 Meadow Brown
1 Small Tortoiseshell
2 Yellow-barred Longhorn (males)
7 Common Blue
1 Dingy Skipper
1 Marbled White (first of the year)
1 Painted Lady (Migrant. First of the year)
1 Large White
1 Yellow Shell
1 Hummingbird Hawk-moth (first I've seen at the site)

Also, at least 6, possibly up to 8 chirpy, newly fledged Nuthatches in the wooded area, grid ref: TL00800269.

Painted Lady (Vanessa cardui), 18 June 2015. A rather worn specimen.

Willow Warblers mixing it up!

There have been at least 2 mixed singing Willow Warblers on Box Moor Trust land this Spring. One at Roughdown Common, around the chalk dell, and one at Bovingdon Brickworks (TL006027). I think both birds are Willow Warblers that are just good mimics. Also, both birds had Chiffchaffs singing closeby on territory. I have tried a number of times to record both birds but sods law applies. Every time I press record, the bird reverts to pure Willow Warbler. Every time I give up and walk away, the bird rattles off a beautiful Willow Warbler refrain followed by chiming Chiffchaff notes. Flipping birds. Anyway, I finally managed to get a half decent recording of the mixed singing bird at the Brickworks this evening.



A few butterflies still fluttering at 5pm around the site:

3 Meadow Brown
4 Speckled Wood
1 Small White
3 Common Blue
3 Dingy Skippers

Also, my first dragonfly of the year:
1 female Broad-bodied Chaser

Adela (Cauchas) fibulella: 14th record for Herts, & Heath Speedwell

The title is a bit of a cheat and quite frankly a blatant pilfer of Ben Sale's far more deserving declaration of the 13th record for Herts. Last week, Ben visited Hexton Pits with the express purpose of finding Adela (Cauchas) fibulella, a day-flying moth (scarce in Hertfordshire), which feeds on Germander Speedwell (Veronica chamaedrys). Ben’s careful searching led to him finding not just 1 but 25 of these diminutive but attractive moths (for Ben's account, click HERE).

Discovering that Germander Speedwell was the all important ingredient, I knew that Bovingdon Brickworks was a possible home for the fibulella. My first opportunity to get there was Monday morning, in overcast, very blustery conditions. Not ideal but worth a punt, I thought. I started searching in the area favoured by the Brown Argus, east of Baker’s Wood, where I knew there was plenty of G. Speedwell. The third clump I came to, there they were. Five of them! One perched, the rest fluttering around the food plant. However, with minimal mothing experience, my identification was tentative at best. I found another single moth, again tentatively identified as the same species, in another area. Once home, I sent photographs to Ben and David K and they very kindly confirmed the ID as Adela (Cauchas) fibulella, a new species for the Brickworks and the 14th record of the moth in Hertfordshire.

Today, conditions were perfect to carry out a more accurate count of the Cauchas fibulella at the Brickworks. I concentrated on 2 large stretches of Germander Speedwell but also checked a couple of smaller clumps in the vicinity. The results were as follows:

Location		Grid Ref		No. of Cauchas fibulella
East of Baker’s Wood		TL00780263		14
Path into site		TL00650270		3
Open area 1		TL00450270		12
Open area 2		TL00440272		2
TOTAL				31

On the way home, I stopped off at Westbrook Hay to check another stretch of Germander Speedwell in Barnfield Meadow (TL02920565). I didn’t spend long there but counted at least 7 fibulella. It may well be that the moth is simply under-recorded rather than scarce but, even so, it’s always nice to add to the species list.

Finally, whilst searching for tiny moths on Monday, I came across what I think is probably Heath Speedwell (Veronica officinalis). I’d never seen it before and it isn’t included in the Brickworks 2011 Plant Survey. Further correspondence with Martin Parr, Conservation Manager at Maple Lodge, suggests that the plant has previously been recorded in the vicinity of the Brickworks but not actually at the site before. So, a new plant to add to the species list as well.

Heath Speedwell (flower stem)

Heath Speedwell (leaf stem)

Heath Speedwell (LEFT); Germander Speedwell (RIGHT)

Common Blues Emerge

A stroll around the Brickworks this morning in warm, sunny, calm conditions. The Common Blue butterflies are now emerging in abundance.

Singing birds of note:

12+ Whitethroats
2 Willow Warblers
7+ Chiffchaff
6+ Blackcaps
3 Song Thrushes

Butterflies of note:

45+ Common Blue
3 Dingy Skipper
2 Speckled Wood
1 Orange-tip (male)
2 Green-veined White
6 Large White
5 Small White
1 Small Tortoiseshell
I couldn’t find any Brown Argus but didn't spend too long looking/waiting in their favoured area.

Brown Argus Foodplant & Emergence

A quick update on the Brown Argus (Aricia agestis) colony at the Brickworks. It’s located on the rough ground east of Baker’s Wood (the area surrounding the grid reference TL00790260).

Brown Argus (Aricia agestis), Bovingdon Brickworks, 21/05/2015

We've identified the presence of Cut-leaved Crane's-bill (Geranium dissectum) growing in shallow, nutrient poor soil on the top of the concrete slabs which now act as a pathway. This is the likely larval foodplant and is exactly the area the Brown Arguses were favouring last August. Being dependant on a low-growing, annual plant (rather than its typical perennial, Common Rock-rose (Heliantbemum chamaecistus), which grows on chalk and limestone soils) puts the colony in rather a precarious position. This is very well explained in the short article by Roger Kemp, HERE.

Brown Argus colony location

Cut-leaved Crane's-bill (Geranium dissectum), Bovingdon Brickworks, 13/05/2015

Cut-leaved Crane's-bill (Geranium dissectum), Bovingdon Brickworks, 13/05/2015

Having spotted the first fresh adult on 10/05/2015, I was very pleased to find 7+ Brown Argus enjoying the warm, sunny conditions this morning in the same area.

Brown Argus (Aricia agestis), Bovingdon Brickworks, 20/05/2015

Other butterflies and moths of note: Orange tip (2m, 1f), Large White (m & f), Small White, Green-veined White, Small Tortoiseshell (3), Peacock (2), Dingy Skipper (3), Common Blue (2m), Burnet Companion moth (1), Silver-ground Carpet moth (2).

In other news... 

...another Box Moor Trust volunteer and experienced butterfly surveyor, counted at least 18 Dingy Skippers on site on 13/05/2015, along with the first record of a Green Hairstreak. Very encouraging indeed!

The Brown Argus are Back!

Brown Argus (Aricia agestis), Bovingdon Brickworks, 10 May 2015

The Brown Argus (Aricia agestis) are back at the Brickworks! Well, one is...and hopefully more will soon emerge. After coming across the colony of 14 at the very end of August last year, it’s encouraging to find that a fresh adult, first generation, is on site. I’ve yet to locate the larval food plants but my flora knowledge is very limited so hopefully someone more clued up will have success. The area in which the adults are seen flying is the rough ground surrounding grid reference TL00800262. The food plants to look out for are:

Common Rock-rose (Helianthemum nummularium), which is used almost exclusively on calcareous grasslands. In other habitats it uses annual foodplants, mainly Dove's-foot Crane's-bill (Geranium molle) and Common Stork'-bill (Erodium cicutarium). There are also recent reports of egg-laying on Cut-leaved Crane's-bill (G. dissectum), Meadow Crane's-bill (G. pratense), and Hedgerow Crane's-bill (G. pyrenaicum).

The Brown Argus butterfly doesn’t seem to be rare across Herts and Middlesex, according to last year’s transect survey results. It was recorded at 26 of the 62 surveyed sites. And, in terms of abundance, it was on a par with the Small Copper. However, its habit of occurring only in small, compact colonies, travelling no more than a couple of hundred metres, at most, from where it emerged, means that the species can be rare at a local level. Ultimately, a total of only 30-35 Brown Argus butterflies were seen at the 9 nearest monitored sites to the Bovingdon Brickworks last year (excluding Aldbury Nowers, a Brown Argus stronghold), so, it is very good news to see it again:

Location Tring Park, Tring Miswell Lane, Tring Lakeside Nature Reserve, Finchley Heartwood Forrest, St Albans Stocker’s Lake, Rickmansworth Sherrards Park Wood, Welwyn Garden City       Roughdown Common, Hemel Hempstead Shrubhill Common, Hemel Hempstead Harpenden Common, Harpenden

Quantity      15 (18)    0    0    9 (9)    0    0    1 (3)    5 (5)    0

(The numbers in brackets represent the total including estimates for weeks missed during the survey)

Dingy Skippers Emerge

Should your heart’s desire be a Dingy Skipper (Erynnis tages), you’ll be hard-pressed to find one in Hertfordshire, unless you visit one or two key sites. Although distributed throughout Britain and Ireland, colonies are often small and localised, and numbers generally have declined rapidly in recent years. In Hertfordshire, it’s as rare as the Green Hairstreaks (Callophrys rubi), according to the results of the 2014 transect survey. There are small populations at Aldbury Nowers (6 recorded in 2013; 12 recorded in 2014); Shrubhill Common (4 recorded in 2014) and Tring Park (1 recorded in 2014).

Last year, I noted 3 possibly 4 Dingy Skippers at Bovingdon Brickworks, which is pretty good going given the other county records. Adults emerge the first week of May so I optimistically visited the Brickworks at the end of last week. No luck. But, today, I was really chuffed to find 2, although keeping track of them and getting even one photograph proved tricky. Best effort below - hopefully there will be other opportunities in the coming weeks.

Dingy Skipper (Erynnis tages), Bovingdon Brickworks, 4 May 2015

There’s no sign yet of last year’s Brown Argus (Aricia agestis) colony. The only other butterflies I saw today were 3 Small White (Pieris rapae), 5 Peacock (Aglais io) and 1 Small Tortoiseshell (Aglais urticae). Not great going for warm conditions (15°C) with sunny spells.

I should also mentioned the Common Whitethroats are back on territory, singing away.

A Common Shrew

I spent the morning following up on David K’s report of the mining bees and also the possibility of Dotted Bee-flies (Bombylius discolor) being on site. There was a lot of mining bee activity, especially on south-facing bare earth, but all the Bee-flies I saw were the common variety, Large Bee-flies (Bombylius major).

The best way to ID the mining bees is probably by netting them and then potting them up. I have no experience of doing that (or the equipment) so my strategy is to photograph them....which is a darn sight easier said than done! In the meantime, I also got slightly distracted by a freshly dead Common Shrew (Sorex araneus), lying on the path. There wasn't any sign of injury but, like the Common Toads from earlier in the month, the main defence mechanism of this little mammal is to secrete a foul tasting liquid from glands in the skin. Predators can quickly abandon them without tucking in.

Unless you have a license to trap and handle live mammals, it's rare you get to see these creatures up close. I wouldn't wish it dead but, since it was, I took the opportunity to check out and photograph its main features.

Common Shrew (Sorex araneus). Body = 70mm long (against my little finger), tail = 45mm (0.5 x length of body)

Pointed nose, small eyes and ears

Alternative view of the long, pointed nose & tiny eyes

Red-tipped teeth

Back feet (from above)

Back feet (from below)

Back foot (from the side)

Front feet

5 Facts About Common Shrews (Sorex araneus)

1. They rarely live beyond 12 months
2. They feed on insects but also eat earthworms and small slugs and snails
3. They don't hibernate but during the winter they actually shrink to make survival easier
4. Their main predators are Tawny Owls, Barn Owls and larger mammals
5. During breeding, if the nest is disturbed or the mother wants to train the young, they form a "caravan". Each shrew grasps the base of the tail (or rump) of the one in front of it, forming a caravan of little shrews all running along behind the mother!

The Mammal Society have a great leaflet on Common Shrews HERE, if you'd like to know more.

As for the mining bees, there was plenty of activity but I'll need to sort out IDs etc before posting. No sign yet of the Common Whitethroats but a Willow Warbler was singing (as had been reported by David earlier in the week).

Solitary Bees

Keep your eyes peeled for little mining bees at the Brickworks. David K sent the following message:

At further Roughdown I was so pleased to see the little chalk 'volcanos' of the mining bees. But, if that wasn't enough, I went to the Brickworks and every open soil area where the dells are was alive with an array of mining bees and wasps. Goodness only knows how anyone identifies them but the best bit was when I walked through what is usually a deeply muddied path to what I can only describe as what is the equivalent of a bit of unimproved chalk grassland near the woods. I looked beneath my feet and what used to be thick yellow mud was like a mini Alps of mining bee mounds. Hundreds of them! I felt so guilty because I trod on a few before I realised but, of course, the egg has been laid already - well beneath the surface with a supply of pollen to help the new larva to survive.

A female Tawny Mining Bee (Andrena fulva), photographed on the road outside the Brickworks, 11/4/2015 

Singing Warblers

A sunny afternoon visit to the Brickworks. I counted at least 9 singing male Chiffchaffs & 2 singing male Blackcaps around the complex. Overhead, 1 Common Buzzard & 1 Red Kite. Numerous Small Tortoiseshell butterflies (Aglais urticae) on the wing, a number of Bee Flies (Bombylius major) and other bee species nectaring on the nearly flowering Cowslips and Forget-me-nots. Ash buds are also bursting into life…