23 May 26

The Flash and Priorslee Balancing Lake

13.0°C > 18.0°C: A clear start. Clouded for a while, then scattered cloud. Light westerly breeze. Very good visibility.

Sunrise: 05:01 BST

* = a species photographed today
$ = a new species for me in this area

A slightly delayed start with The Flash first and only one lap of the lake.

Priorslee Balancing Lake: 07:05 – 09:50

(121st visit of the year)

Bird notes:
- the seven Greylag Geese goslings present and correct.
- no Mallard ducklings seen.
- two broods of juvenile Coots seen. Numbers provisional as they were in and out of the reeds.
- one Great Crested Grebe was seen carrying a small fish, I assume to its partner on a nest hidden in the reeds
- three of the eight Reed Warblers heard were in scrub vegetation rather than in reeds,
- a Garden Warbler was heard singing from the bushes between the lake and the M54 about as far away from the paths as possible.
- juvenile Goldfinches seen being fed by parents.

Bird(s) noted flying over here:
- 2 Greylag Geese: flew East together
- 1 Lesser Black-backed Gull
- 2 Wood Pigeons
- 1 Jackdaw
That's all folks.

Counts from the lake area:
- 2 Canada Geese: of these two pairs departed
- 2 + 7 (1 brood) Greylag Geese
- 2 Mute Swans
- 16 (12♂) Mallard
- 1 Moorhen only again
- 22 + 5 (2 broods) Coots: see notes
- 3 Great Crested Grebes: see notes

Hirundines etc. noted:
- 1 Swift sped through

Warblers noted (the number in brackets refers to birds singing):
Number perhaps incomplete as I was not present for the dawn chorus
- 13 (10) Chiffchaffs
- 8 (8) Reed Warblers: see notes
- 18 (17) Blackcaps
- 1 (1) Garden Warbler

Also noted

Butterflies:
- *1 female Large White Pieris brassicae
- *2 Speckled Wood Pararge aegeria

Moths:
- *2 Common Nettle-taps Anthophila fabriciana: moth species #10 here this year for me.
- *1 Silver-ground Carpet Xanthorhoe montanata
My 2026 moth species total moves on to #23.

Bees, wasps etc.:
- Tree Bumblebee Bombus hypnorum
- Early Bumblebee Bombus pratorum

Hoverflies:
- Buttercup Blacklet Cheilosia albitarsus [Late Buttercup Cheilosia]
- Tiger Hoverfly Helophilus pendulus [Tiger Marsh Fly; Sun Fly]
- *Blotch-winged Hoverfly Leucozona lucorum [Blotch-winged Whitebelt]

Damsel / Dragon-flies:
- *Common Blue Damselfly Enallagma cyathigerum [Common Bluet]

Other flies:
- root-maggot fly Anthomyia procellaris
- dagger fly Empis tessellata
- *cranefly Limonia phragmitidis
- Scorpion Fly Panorpa sp.
- Yellow Dung Fly Scathophaga stercoraria
- other unidentified fly species

Bugs:
- none

Beetles:
- *2 Spot Ladybird Adalia bipunctata
- Alder Leaf Beetle Agelastica alni
- *Soldier beetle Cantharis pellucida
- 7 Spot Ladybird Coccinella 7-punctata
- *Green Dock Beetle Gastrophysa viridula
- *Harlequin Ladybird Harmonia axyridis var. spectabilis
- *Harlequin Ladybird Harmonia axyridis var. succinea
- False Blister Beetle Oedemera lurida or O. virescens
- *Swollen-thighed Beetle Oedemera nobilis [False Oil Beetle or Thick-legged Flower Beetle]
- *Nettle Weevil Phyllobius pomaceus

Spiders, harvestmen etc.:
- *wolf spider Pardosa sp.
- *Long-jawed Orb-web Spider Tetragnatha sp.

A female Large White Pieris brassicae . It is a female because there are four spots in the wings (just two in a male). And a Large White because the black of the wing-tip significantly extends down both edges.

A Speckled Wood butterfly Pararge aegeria

A Common Nettle-tap moth Anthophila fabriciana.

"Record shot" - just about! A Silver-ground Carpet Xanthorhoe montanata. The dark cross-line on the silvery background identifies this moth. commonly disturbed from vegetation for the next few weeks. I should get a better photo.

A Blotch-winged Hoverfly Leucozona lucorum. For a hoverfly the antennae are unusually long.

The club-shaped mark on the first obvious body segment identifies this as a male Common Blue Damselfly Enallagma cyathigerum.

And a female who may or may not become fully blue.

A different-looking cranefly. This is the cranefly Limonia phragmitidis. It is a female with the ovipositor.

A 2 Spot Ladybird Adalia bipunctata. I do not often see this species these days. It is being out-competed by the larger and alien Harlequin Ladybird Harmonia axyridis. This species has several forms sometimes with a black-based elytra and four or six spots.

Definitely a beetle morning. Here is a Soldier beetle Cantharis pellucida

On the left is a Green Dock Beetle Gastrophysa viridula. The other one would look more like an Alder Leaf Beetle Agelastica alni apart from the pale green areas. I cannot explain.

A Harlequin Ladybird of the less common spectabilis form (complete with part of a thumb-nail)

And here two Harlequin Ladybirds of the more common form succinea are mating. Mating between the forms is common but the offspring are not hybrids but true to one or other of the forms.

My first Swollen-thighed Beetle Oedemera nobilis of this year. Only the males have the swollen thighs but note how the wing cases (elytra) are held slightly open...

...as they are on the female as shown here.

A well-posed Nettle Weevil Phyllobius pomaceus . When freshly emerged they look like this. The green scaling quickly wears away.

A side-elevation view of another.

And a pair mating. As noted above the green scaling is wearing away.

A wolf spider Pardosa sp. is hardly camouflaged in the buttercup!

A Long-jawed Orb-web Spider Tetragnatha sp. sitting in its web apparently with breakfast in its mouth.

Spiders have been here! The remains of two craneflies.

(Ed Wilson)

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In the Priorslee Avenue tunnel:

Flies:
- 14 midges of several species
- 1 caddis fly
- 1 cranefly

Arthropods:
- *1 Common Shiny Woodlouse Oniscus asellus

Spiders, harvestmen etc.:
- 1 Long-jawed Orb-web Spider Tetragnatha sp.

The only "interesting" occupant of the tunnel was this Common Shiny Woodlouse Oniscus asellus.

(Ed Wilson)

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The Flash: 05:55 – 07:00

(119th visit of the year)

Bird notes:
- back to the five visiting Mute Swans and the presumption of the resident pen on the nest.
- only one Canada Goose goslings seen and that seemed to be smaller than any seen recently. A larger number of adults were seen than on recent days.
- just two Greylag Geese departed together,
- only two juvenile Coots seen. However the area where the two broods each of four were in an area where (pre-?) *spawning Common Carp Cyprinus carpio were thrashing about sending birds scattering.
- a single adult Great Crested Grebes seen.

Bird(s) noted flying over here:
- 2 Lesser Black-backed Gulls: adults, separately
- 1 Grey Heron

Noted on / around the water:
- 51 + 1 (1 brood) Canada Geese: of these at least eight departed as a pair and two trios
- 2 Greylag Geese: departed together
- 7 Mute Swans: assuming the pen is on the hidden nest?
- 25 (20♂) Mallard
- 3 Moorhens yet again
- 24 + 2 (1 broods) Coots: see notes
- 1 Great Crested Grebe

Hirundines etc. noted:
None

Warblers noted (the number in brackets refers to birds singing):
- 4 (4) Chiffchaffs
- 5 (5) Blackcaps

Notes around the area:

Moths:
- *1 Common Marble Celypha lacunana: moth species #12 for me here in 2026

Bees, wasps etc.:
- none

Flies:
- various other unidentified flies and midges

Beetles:
- none

Spiders, harvestmen etc.:
- *Stout Sac Spiders Clubiona sp.

A pair of Canada Geese with just one gosling. On size the male (gander) is leading.

Not a very good photo of a Common Marble moth Celypha lacunana sitting in full sun. I should see more.

On one of the street lamp poles I noted this Stout Sac Spider Clubiona sp. with two of its eight eyes catching eye-shine from the camera flash.

And on the adjacent street lamp poles was another, this one clearly a male.

Common Carp Cyprinus carpio thrashing about in the water and scattering the birds.

(Ed Wilson)

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2006
Priorslee Lake
Mink seen by locals
(Ed Wilson)