17 Apr 26

Priorslee Balancing Lake and The Flash

9.0°C > 13.0°C: Another mostly overcast start with very light drizzle. Cleared to scattered cloud below a high overcast giving some watery sunshine. Moderate southerly wind, increasing fresh at times. Very good visibility.

Sunrise: 06:08 BST

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

Many, but not all, Willow Warblers seem to have passed through.

Priorslee Balancing Lake: 05:35 – 06:35 // 07:25 – 09:55

(92nd visit of the year)

New bird species:
Another addition to my 2026 bird list for here: a Common Whitethroat was singing from the Ricoh hedge c.09:30. Species #78 this year for me.

Other bird notes:
- four Common Sandpipers were seen standing on the boating platform in the south-west area at 05:45. I heard calls as I walked across the dam at c.06:00 but saw nothing. A single bird was seen flying along the dam-face c.08:10. So at least four...
- two adult Lesser Black-backed Gulls were on the south-west grass by 05:45: are these the same two each morning? Later three very smart-looking adults dropped in c.07:45.
- a Grey Heron seen flying West as I was walking back up Teece Drive is presumed to be the bird from the lake departing.
- * noted my first spotty juvenile Robin of the year.
- unexpected was at least two Lesser Redpoll both calling and singing from tree tops near the Teece Drive gate.
- a noisy group of c.20 Goldfinches were flying around trees in Teece Drive (a few pairs were also seen elsewhere). I do not expect to see flocks of this species at this date.
- a late record of a Siskin: a single bird was seen, also in tree tops around the Teece Drive gate (my last record here was on 16 March).
- a Reed Bunting was heard calling and giving intermittent song along the South side c.05:50. One was heard along the North side c.07:50 before flying off high South over the lake to...? A female was seen along the North side c.09:15. How many birds involved?

Bird(s) noted flying over here:
- 1 Canada Goose: flew North and presumably the same flew East a few minutes later
- 2 Herring Gulls
- 1 Lesser Black-backed Gull
- 1 Feral Pigeon
- 12 Wood Pigeons
- 10 Jackdaws

Counts from the lake area:
- 2 Canada Geese: pair arrived and much later departed
- 6 Greylag Geese: arrived together but in two groups of three; departed later
- 2 Mute Swans: the pen on the nest most of the time
- 10 (8♂) Mallard
- 9 (6♂) Tufted Duck
- 2 Moorhens only
- 21 Coots yet again
- 7 Great Crested Grebes
- *5 Lesser Black-backed Gulls
- 1 Cormorant: immature, arrived
- 1 Grey Heron

Hirundines etc. noted:
- 5 Sand Martins
- 2 Barn Swallows
birds seemed to be passing through so it is likely more individuals were involved

Warblers noted (the number in brackets refers to birds singing):
- *1 (1) Cetti's Warbler
- 4 (4) Willow Warblers
- 13 (11) Chiffchaffs
- 3 (3) Sedge Warblers again
- 2 (2) Reed Warblers
- 15 (14) Blackcaps
- 1 (1) Common Whitethroat

On the West end street lamp poles post-dawn:

Bees, wasps etc.:
- *1 ichneumon Ophion obscuratus

Beetles:
- *1 Alder Leaf Beetle Agelastica alni

Noted around the area later:
[numbers only given for moths and butterflies unless exceptional counts noted]

Butterflies:
- *1 Peacock Aglais io

Bees, wasps etc.:
- *Buff-tailed Bumblebee Bombus terrestris

Hoverflies:
- *Syrphus sp. S. ribesii / S. vitripennis

Other flies:
- *Bluebottle Calliphora vomitoria
- *Spotted Cranefly Nephrotoma appendiculata
- *Tachinid fly Phasia hemiptera
- *Yellow Dung Fly Scathophaga stercoraria
- also a number of both *interesting and uninteresting unidentified flies of at least five species.

Bugs:
- *Dock Bug Coreus marginatus

Beetles:
- 7 Spot Ladybird Coccinella 7-punctata

An adult Lesser Black-backed Gull takes a drink and as it does so it presents the left wing to highlight some ID features: a broad white terminal area to the secondaries; a white "mirror" on the outer primary only; and a contrast between the dark grey of the inner wing and the even darker primary feathers.

There is often a twig in the way! The black and blue chequered pattern on the wing feathers shows well though.

Here in flight we see the very characteristic rounded wings and also note how the white on the rump wraps around to the under-tail.

Looking eager to get somewhere.

A typical flying silhouette.

Not so much a twig in the way: more like half a tree. I knew the Cetti's Warbler was headed this way to perch in one of its favourite trees but could not predict precisely where.

A spotty juvenile Robin looks at me – perhaps I am the first human it has seen. Then again...

The juveniles cannot have a red breast as that is the feature that causes territorial aggression by the adults (I never understand how this species declares temporary "peace" to pair-up for the breeding season)

"I am the king of the castle". Actually "queen" as this is a female Pied Wagtail.

A splendid, fresh-looking, Peacock butterfly Aglais io. The "eyes" are thought to deter/confuse/startle potential predators.

Looking at the wings on this large (queen?) Buff-tailed Bumblebee Bombus terrestris you have to agree with the scientists who concluded that bumblebees cannot possibly fly!

The only two insects on all the street lamp poles pre-dawn were this ichneumon wasp and Alder Leaf Beetle Agelastica alni.

A close-up of the ichneumon. The pale stripes on the thorax are sufficient to identify it as Ophion obscuratus: none of the several other Ophion species has these stripes.

A side-elevation view shows how narrow the "wasp waist" is and makes you wonder how it controls its abdomen.

It is always the way. A Syrphus hoverfly exposing the entire hind leg which would enable separation between S. ribesii and S. vitripennis had it been a female. But it is a male.

A root-maggot fly, probably an Anthomyia species.

Another root-maggot fly, this one with yellow halteres.

This fly is the Bluebottle Calliphora vomitoria . What an attractive scientific name! Now altogether - "ying tong, ying tong..." (ask your (grand?) parents).

With wings closed preventing the abdomen pattern being visible I cannot be 100% sure of the identity of this as a Spotted Cranefly Nephrotoma appendiculata. Craneflies are usually thought of as autumnal-flying insects and certainly so far as sheer numbers are concerned that is true. There are many species that are active during Spring and Summer.

This Muscid fly is probably a Phaonia rufiventris though the angle prevents positive identification.

The fly "find of the day" though it is not an uncommon species. It is a female Tachinid fly Phasia hemiptera. The males look significantly different with curved wings with dark markings. Both sexes can show variable amounts of orange on the abdomen.

A Yellow Dung Fly Scathophaga stercoraria.

This is a Dock Bug Coreus marginatus. One of the easiest bugs to identify with a unique shape.

(Ed Wilson)

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In the Priorslee Avenue tunnel:

Flies:
- 4 midges
- *1 cranefly Tipula vittata

The cranefly Tipula vittata. The distinctive wing pattern of this species shows well on the right wing.

(Ed Wilson)

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The Flash: 06:40 – 07:20

(89th visit of the year)

Bird notes:
- a few Tufted Duck back.
- a Great Crested Grebe was again seen only on the nesting platform.
- no Sedge Warbler heard.

Bird(s) noted flying over here:
- 1 Lesser Black-backed Gull

Noted on / around the water:
- 12 Canada Geese: none seen flying in or out
- 5 Greylag Geese
- 2 Mute Swans
- 15 (13♂) Mallard only
- 5 (3♂) Tufted Duck
- 2 Moorhens only
- 18 Coots
- 1 Great Crested Grebe

Warblers noted (the number in brackets refers to birds singing):
- 3 (3) Willow Warblers
- 6 (5) Chiffchaffs
- 7 (7) Blackcaps

Noted around the area later:

Lacewings and allies:
- *1 Common Green Lacewing Chrysoperia carnea

Flies:
- 1 male small plumed midge

Beetles:
- 1 Alder Leaf Beetle Agelastica alni

Probably the same Song Thrush I photographed with a worm on Wednesday here still looking for breakfast.

A rather scruffy-looking Wren (I know: glass-houses and stones). A wing feather askew and a ragged-looking tail.

The tail looks better here: the wing-feather is still askew.

A Common Green Lacewing Chrysoperia carnea in full Summer "green" colour.

(Ed Wilson)

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2014
Priorslee Lake
1 Cormorant
2 Grey Herons
8 Greylag Geese
10 Tufted Duck
1 Sand Martin
4 Swallows.
1 Sedge Warbler
10 Blackcaps
7 Chiffchaffs
191 Jackdaws
(Ed Wilson)

Woodhouse Lane
2 Red-legged Partridges
1 Whitethroat
4 Skylarks
1 Blackcap
1 Chiffchaff
1 Linnet
2 Yellowhammers
(Ed Wilson)

Nedge Hill
1 Wheatear
1 Common Whitethroat
1 Willow Warbler
3 Chiffchaff
2 Swallow
2 Blackcap
6 Skylark
1 Great Spotted Woodpecker
(Martin Grant)

2013
Nedge Hill
1 Common Redstart
5 Whitethroat
15 Wheatear
2 Swallows
Chiffchaff
2 Yellowhammer
6+ Skylarks
3 Linnet
(Ian Grant, Martin Grant)

2012
Priorslee Lake
1 Dark-bellied Brent Goose
(John Isherwood)

Nedge Hill
1 Redstart
2 Wheatear
1 Raven
(John Isherwood)

2011
Priorslee Lake
1 Common Sandpiper
2 Tufted Ducks
1 Lapwing
1 Siskin
Common Whitethroat
(John Isherwood/Ed Wilson)

Nedge Hill
1 Common Redstart
12 Wheatear
(John Isherwood)

2010
Priorslee Lake
1 Common Sandpiper
(John. Isherwood)

2009
Priorslee Lake
2 Reed Warblers
1 Pochard
17 Tufted Duck
6 Swallows
2 Reed Warblers
4 Blackcaps
5 Chiffchaffs
1 Willow Warbler
1 Jay
(Ed Wilson)

2008
Priorslee Lake
1 Little Grebe
1 Gadwall
7 Tufted Ducks
1 Common Sandpiper
111 Sand Martins
1 House Martin
4 Swallows
1 Blackcap
4 Willow Warblers
11 Chiffchaffs
1 Common Tern
(Ed Wilson)

2006
Priorslee Lake
4 Great Crested Grebes
3 Tufted Ducks
3 Ruddy Duck
9 Common Sandpiper
11 Chiffchaff
8 Willow Warbler
4 Blackcaps
1 Common Whitethroat
1 Swallow
1 Willow Tit
5 Greenfinch
1 Linnet
1 Redpoll
4 Reed Bunting
(Martin Adlam)