Friends of Priorslee Lake Wildlife Site: 20 May 23

Priorslee Lake and The Flash

8.0°C > 13.0°C: Mainly clear with very few light mist patches early. Light north-easterly breeze. Hazy early otherwise very good visibility.

Sunrise: 05:06 BST

* = a photo of this species today

Priorslee Balancing Lake: 05:00 – 06:25 // 07:25 – 09:15

(104th visit of the year)

Bird notes:
- nothing special.

Birds noted flying over here:
- 3 Canada Geese: a single and a duo outbound
- 5 Wood Pigeons only
- *4 Cormorants: together
- 4 Lesser Black-backed Gulls
- 4 Jackdaws
- *1 Rook

Warblers noted (the number singing in brackets):
- 1 (1) Cetti's Warbler
- 2 (2) Willow Warblers
- 10 (8) Chiffchaffs
- 1 (1) Sedge Warbler
- 8 (7) Reed Warblers
- 8 (8) Blackcaps
- 1 (1) Garden Warbler
- *1 (1) Common Whitethroat

Hirundines etc., noted:
- 5 Swifts
- 4 Barn Swallows

Counts from the lake area:
- *7 + 1 (1 brood) Canada Geese: still just one gosling with parents; also an adult trio for a while; an adult pair arrived
- *2 Greylag Geese: departed
- 2 + 2 (1 brood) Mute Swans
- 3 (2♂) Mallard
- 4 Moorhens
- 25 + 14 (6 broods) Coots
- *7 Great Crested Grebes
- 1 Lesser Black-backed Gull: immature, briefly

Noted on the street lamp poles around dawn:
- 1 small fly again

Noted later: the north-easterly breeze was keeping the sunny areas cool:
+ = my first sighting of this species this year

Butterflies:
- +*Green-veined White (Pieris napi)
- *Speckled Wood (Pararge aegeria)

Bees / wasps etc.:
- Buff-tailed Bumblebee (Bombus terrestris)

Dragon-/damsel-flies:
- Azure Damselfly (Coenagrion puella)
- Common Blue Damselfly (Enallagma cyathigerum)
- *Red-eyed Damselfly (Erythromma najas)

Hoverflies:
- Cheilosia albitarsus agg. (C. ranunculi (Early Buttercup Cheilosia) or C. albitarsis (Late Buttercup Cheilosia))
- *Marmalade Hoverfly (Episyrphus balteatus)
- Tapered Dronefly (Eristalis pertinax)
- *Tiger Hoverfly (Helophilus pendulus)
- Syrphus sp. (S. ribesii / S. vitripennis)

Other insects:
- *Alder Fly (Sialis lutaria)
- Red-and-Black Froghopper (Cercopis vulnerata)
- Alder Leaf Beetle (Agelastica alni)

Also
- *Nursery Web Spider (Pisaura mirabilis)

The two Canada Geese with their surviving gosling were on the other side of Castle Farm Way early, well out of reach of the cob Mute Swan. Later they had successfully crossed the road and were back on the dam top.

The two Greylag Geese, now without any goslings, were also on the other side of Castle Farm Way early on. They flew off later.

A bit too far away really. This Great Crested Grebe is struggling with a fish it has caught.

It has maneuvered it to go down head-first but is still struggling.

Almost gone!

A party of four Cormorants flew over. The bird in the lead is an adult still showing a trace of the white thigh patch from the breeding season. A pale-bellied immature behind it. Number three also shows a hint of pale on the belly.

I have no idea what this Rook is carrying. Note the bare skin around the base of the bill. It also seems to have a full crop.

The constantly singing Common Whitethroat has not been sitting on the top of trees very much. It did so briefly this morning. I am not sure what happened to the pair seen over a week ago at the other end of the lake. Perhaps they are too busy nesting for the male to be singing.

My first Green-veined White butterfly (Pieris napi) of the year. A female because it has a black spot in every wing.

A rather battered-looking Speckled Wood butterfly (Pararge aegeria).

A Red-eyed Damselfly (Erythromma najas) with some colour to the body and diagnostic red eyes.

A Marmalade Hoverfly (Episyrphus balteatus) showing its distinctive banded abdomen.

This seems to be a Tiger Hoverfly (Helophilus pendulus). It is more orange-toned than usual.

At the time I thought this to be an ichneumon from the way it was running around the leaf and the pale on the legs. The photo reveals it not to have the long antennae of that group of insects and I now suspect it is a hoverfly. I need to do more research.

A sticky end for this Alder Fly (Sialis lutaria) which I had probably flushed in to the spider's web.

Another Nursery Web Spider (Pisaura mirabilis).

(Ed Wilson)

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The Flash: 06:30 – 07:20

(95th visit of the year)

Bird notes:
- *The pen Mute Swan came off the nest with all eight cygnets present and correct.
- *What looked like a duck Gadwall was calling like a drake and chasing a duck Mallard! A photo showed it to be a moulting drake.
-*A brood of two Mallard comprised smaller looking ducklings than the trio I saw yesterday.

Birds noted flying over here:
- 3 Jackdaws

Warblers noted (the number singing in brackets):
- 4 (4) Chiffchaffs
- 3 (2) Blackcaps

Hirundines etc., noted:
- 2 Swifts

Noted on / around the water
- 17 Canada Geese again
- no Greylag Geese
- *3 + 8 Mute Swans
- *1 (1♂) Gadwall: see notes
- *18 (15♂) + 2 (1 brood) Mallard
- 1 (1♂) all-white duck (Peking(?) Duck)
- 8 (5♂) Tufted Duck
- 8 Moorhens
- 24+ 4 (3 broods) Coots
- 4 Great Crested Grebes
- 1 Cormorant: see notes

On / around the street lamp poles:

Nothing noted

Noted elsewhere:
- *Tiger Hoverfly (Helophilus pendulus)
- Alder Leaf Beetle (Agelastica alni)
- presumed Raspberry Beetle (Byturus tomentosus)

Count carefully. All eight cygnets are present.

The Gadwall that had me puzzled as it looked like a duck but called like a drake. This shows that it is a drake and now moulting out of breeding plumage.