18 Jun 23

Priorslee Lake and The Flash

15.0°C > 18.0°C: Broken cloud early. Some clearer spells later but also cloudy at times with a shower passing to the North. Light easterly breeze. Very good visibility.

Sunrise: 04:46 BST

* = a photo of this species today

+ = my first sighting of this species at this site this year.
++ = new species for me at this site.

Priorslee Balancing Lake: 05:05 – 06:05 // 07:10 – 09:50

(130th visit of the year)

Bird notes:
- Perhaps it was a bit too early when I counted the juvenile Coots and some were still inside the reeds. Many fewer than I recorded yesterday.
- One of the fishermen reported a tern fishing in the lake yesterday afternoon: almost certainly a Common Tern.
- The Garden Warbler was back singing beside the sailing club HQ again – assuming this is the same one I usually (but not today) hear along the South side.

Birds noted flying over here:
- 8 Greylag Geese: single outbound; septet inbound together
- 1 Feral Pigeon
- 2 Stock Doves: together
- 7 Wood Pigeons
- 1 Grey Heron
- 8 Jackdaws
- 5 Rooks

Warblers noted (the number singing in brackets):
- 1 (1) Cetti's Warbler
- 1 (1) Willow Warbler
- 10 (10) Chiffchaffs
- no Sedge Warbler
- 9 (9) Reed Warblers
- 14 (12) Blackcaps
- 1 (1) Garden Warblers
- 4 (0) Common Whitethroats

Hirundines etc., noted:
- 2 Swifts
- 3 Barn Swallows
- 2 House Martins

Counts from the lake area: it remains very quiet
- 2 + 2 Mute Swans
- 1 (1♂) Mallard
- 2 Moorhens
- 26 + 16 (6? broods) Coots
- 13 + 4 (1 brood) Great Crested Grebes
- 2 Lesser Black-backed Gulls: separately, briefly

On and around the street lamp poles around dawn:

Nothing noted

Noted later:

Butterflies:
- +*Ringlet (Aphantopus hyperantus)
- Meadow Brown (Maniola jurtina): one flushed at 05:25 the only one seen
- Comma (Polygonia c-album)

Moths:
- Timothy Tortrix (Zelotherses paleana)
- Common Marble (Celypha lacunana)
- unidentified grass moths
- Silver-ground Carpet (Xanthorhoe montanata)

Bees / wasps etc.:
- Honey Bee (Apis mellifera)
- Garden Bumblebee (Bombus hortorum)
- Early Bumblebee (Bombus pratorum)
- sawfly Tenthredo sp.

Dragon-/damsel-flies:
- Azure Damselfly (Coenagrion puella)
- Common Blue Damselfly (Enallagma cyathigerum)
- Blue-tailed Damselfly (Ischnura elegans)
- *unknown damselfly

Hoverflies:
- +Bumblebee Blacklet (Cheilosia illustrata)
- *unidentified Cheilosia sp.
- Marmalade Hoverfly (Episyrphus balteatus)
- *Tapered Dronefly (Eristalis pertinax)
- Common Dronefly (Eristalis tenax)
- *Common Spotted Field Syrph (Eupeodes luniger)
- *Common Twist-tail (Sphaerophoria scripta)
- *Syrphus sp. (S. ribesii / S. vitripennis)

Other flies:
- *Black Snipefly (Chrysopilus cristatus)
- +*Dagger fly Empis livida
- Semaphore fly (Poecilobothrus nobilitatus)
- a greenbottle
- various flies
- *aphid

Beetles:
- Alder Leaf Beetle (Agelastica alni)
- *possible flea beetles Derocrepis rufipe
- Swollen-thighed Beetle (Oedemera nobilis)

Bugs:
- *Mirid Bug Leptopterna dolabrata
- *14 Spot Ladybird (Propylea quattuordecimpunctata)

Also
- White-lipped Snail (Cepaea hortensis)
- +*unidentified tiny spider
- +*flowers of Convolvulus sp. probably Field Bindweed (Convolvulus arvensis)
- +*flowers of Imperforate St John's-wort (Hypericum maculatum)
- +*flowers of Common Ragwort (Jacobaea vulgaris)

Not an inspiring sunrise.

Hazy sun behind high cloud.

Well this IS a Grey Wagtail but not a juvenile. Looks constipated!

My first Ringlet butterfly (Aphantopus hyperantus) of the year. The 'rings' are more obvious on the underwing. Relatively easy to separate from the Meadow Brown (Maniola jurtina) by its lack of any orange tones. The pale wing border which is surprisingly apparent even in flight.

A strange one this. A damselfly freshly emerged from the exuvia on the left. But why does it look green?

A close-up of the thorax does not help in revealing any obvious markings. Common Blue Damselfly (Enallagma cyathigerum) has a green form of the mature female but that emerges, like most damselflies, looking pale brown.

Also the markings on the abdomen segments are more typical of a male. Pass.

I am fairly certain this is a species of Cheilosia hoverfly but I have no idea which. There are 40 species on the UK list and they are mostly all black. This one has worn wings.

Luckily this is a male Tapered Dronefly (Eristalis pertinax). Had it been a female I would have needed to check markings on the legs to separate it from other Eristalis hoverflies.

I don't find this group of hoverflies easy to specifically identify. I think Common Spotted Field Syrph (Eupeodes luniger).

Even though the closed wings are covering many of the abdomen markings it is relatively easy to ID this hoverfly as a Common Twist-tail (Sphaerophoria scripta). The very obvious yellow scutellum behind the thorax with two stripes are identification features. Also the abdomen extends well beyond the wings giving this species its alternative name of Long Hoverfly. The abdomen of females though is much shorter.

A wonderfully clear view of the hind leg of this Syrphus hoverfly but, as ever, it is a male so the feature cannot be used to separate S. ribesii from S. vitripennis.

An unusual perspective of a male Black Snipefly (Chrysopilus cristatus) showing its proportionately long legs. Note the slim all-dark body.

And this is the female. She looks very different but shares with the male the dark mark in the wing. This is the first female I have noted: I have seen many hundred males.

This is the Dagger fly Empis livida. I also recorded my first for the year on the same date last year. Nice dagger!

I have no idea what this species of fly is or what it is doing.

Not sure how this will look 'on screen'. A tiny creature that seems to be an aphid. I don't think it is guilty of making the two holes in the leaf as aphids feed on sap.

Beetle-mania? (or have I done that one?). Many pollen beetles, just possibly Derocrepis rufipe, feeding on a buttercup.

"Another chance to see..." the Mirid Bug Leptopterna dolabrata.

A 14 Spot Ladybird (Propylea quattuordecimpunctata). This species rarely has 14 spots. Unlike the other yellow and black species the spots vary in shape and size.

A tiny spider I found running along the hand-rail of the 'boxing ring'.

A Convolvulus flower, probably Field Bindweed (Convolvulus arvensis).

Flowers of Imperforate St John's-wort (Hypericum maculatum). The black lines, most obvious on the buds, separate this species from other St John's-worts.

Just about to open are these flowers of Common Ragwort (Jacobaea vulgaris). They will be an important nectar source for all manner of insects in the weeks to come.

(Ed Wilson)

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The Flash: 06:10 – 07:05

(120th visit of the year)

Bird notes:
- The Mallard ducklings in today's brood were too far away for me to count but I was shown a photo of them.
- Where have the Tufted Duck gone?

Birds noted flying over here:
- 3 Cormorants: together
- 2 Starlings

Warblers noted (the number singing in brackets):
- 7 (6) Chiffchaffs
- 1 (1) Blackcap

Hirundines etc., noted:
- 2 Swifts
- 2 House Martins

Noted on / around the water
- 141 Canada Geese
- 1 Canada x Greylag Goose
- 45 Greylag Geese
- 2 + 4 Mute Swans
- 27 (21♂) + 6 (1 brood) Mallard
- 1 (1♂) all-white duck (Peking(?) Duck)
- 10 (>3♂) Tufted Duck: five of these flew off before I could determine their sex
- 4 Moorhens
- 23 + 8 (4 broods) Coots
- 2 Great Crested Grebes

On / around the street lamp poles around the water:

Nothing noted

Noted elsewhere:
- Marmalade Hoverfly (Episyrphus balteatus)
- Tapered Drone Fly (Eristalis pertinax)
- Common Blue Damselfly (Enallagma cyathigerum)
- Black Snipefly (Chrysopilus cristatus)
- ++Semaphore fly (Poecilobothrus nobilitatus)
- Yellow Dung Fly (Scathophaga stercoraria)
- Alder Leaf Beetle (Agelastica alni)
- possible flea beetles Derocrepis rufipe

What I presume is the same rather pale brown duck Mallard has been around for several years. Today was my first sighting of it for many weeks.

 Five Tufted Duck depart.

One of them was a drake. I am always surprised how wide ducks' bills are when viewed from directly underneath. Almost as if they are Shovelers.

Oops: this IS a Common Blue Damselfly (Enallagma cyathigerum) which means that a senior moment and / or the onset of senility means I misidentified the emergent damselflies at the Balancing Lake on both Friday and Saturday. They were this species and not Azure Damselflies (Coenagrion puella) as I suggested. It is the Common Blue that has the wide blue stripe on the thorax. Apologies.

The pale tips to the wings of this Semaphore fly (Poecilobothrus nobilitatus) indicate it is male. He waves his wings to attract females. I have not recorded this species here previously.

Flea beetles are everywhere at the moment. Here on a Dog Rose (Rosa canina agg.). I was told that all attendees at the Priorslee Residents Association Summer Fayre(!), held yesterday on the Holy Trinity Academy 'football field' had to wear Hi-viz(!) and these proved a magnet for the beetles.

(Ed Wilson)

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On this day can be found via the yearly links in the right-hand column.

Sightings from previous years without links are below

2010
Trench Lock Pool
4 drake Pochard
(Ed Wilson)