12 Sep 22

Priorslee Lake and The Flash

15.0°C > 17.0°C: Better than forecast: no rain; broken medium-level cloud with larger breaks developing and some sun. Light and variable breeze. Very good visibility.

Sunrise: 06:38 BST

* = a photo from today

Priorslee Lake: 05:25 – 09:25

(195th visit of the year)

I read in the Belvide blog Here that visible Autumn migration has been noted there. Apart from departing Barn Swallows I have noted no movements over here as yet here.

Bird notes:
- 12 of the 19 Feral Pigeons were noted flying far to the West and were likely 'roof birds' that I see around The Flash daily. The other seven flew NW and could have been Racing Pigeons.
- Presumably the same juvenile Common Tern was present again. Today it was being chased by some of the Black-headed Gulls which is possibly why it moved to The Flash later.
- One or more House Martins were heard high over the estate area at 06:50 but not located: one was seen flying South over the lake at 08:40: then at 09:15 I noted 18 high over the Ricoh grounds.
- Jackdaws remain remarkably scarce at the moment. Perhaps feeding in a different area with the roost departure taking them elsewhere.

Birds noted flying over here:
- 12 Canada Geese: 10 outbound in two groups; duo inbound
- 19 Feral Pigeons: see notes
- 4 Stock Doves: two singles and a duo
- 94 Wood Pigeons
- 1 Collared Dove
- 25 unidentified large gulls
- 3 Lesser Black-backed Gulls
- 52 Rooks
- 3 Jackdaws
- 1 Starling

Hirundines etc. noted:
- >18 House Martins: see notes

Warblers noted (no song recorded unless specifically noted):
- 1 Cetti's Warbler: sang in the north-west corner pre-dawn and then in the north-east area later
- 7 Chiffchaffs: two in song
- 1 Blackcap

Counts from the lake area:
- 2 + 4 (1 brood) Mute Swans
- *3 (1♂) Gadwall
- 15 (10♂) Mallard
- 1 (?♂) Tufted Duck: flew in at 07:55; not seen again
- 8 Moorhens
- 143 Coots
- 1 Little Grebe
- *12 + 10 (5 broods) Great Crested Grebes
- >80 Black-headed Gulls: 74 of these were on the football field at 06:50
- 1 Yellow-legged Gull: same(?) first winter
- 1 Lesser Black-backed Gull
- 1 Common Tern: juvenile
- 2 Grey Herons: sparring over the water at 06:20; neither seen again

Noted on / around the street lamp poles pre-dawn:
- *1 ichneumon sp.
- 1 plumed midge, perhaps Chironomus plumosus
- *1 red fly
- *1 springtail Pogonognathellus longicornis-type
- *1 Common Green Capsid (bug) (Lygocoris pabulinus)
- *possible Dusky Slug (Arion subfuscus)
- 1 Bridge Orb-web Spider (Larinioides sclopetarius)

Noted later:

Moths:
- *leaf mines, perhaps of the Common Oak Midget (Phyllonorycter quercifoliella)

Hoverflies:
- *Marmalade Hoverfly (Episyrphus balteatus)

Flies:
- *Yellow Swarming Fly (Thaumatomyia notata)
- greenbottle Lucilia sp.

Beetles:
- Alder Leaf Beetle (Agelastica alni)

Fungus:
- *Field Mushroom (Agaricus campestris)

Mammals
- Grey Squirrel

Plants:
- *Winter Heliotrope (Petasites fragrans) leaves

The forecast had been for rain so why was I not surprised...

Coloured up quite well – but "red sky in the morning...." and it did rain much later.

Another view of the drake Gadwall. He still has some feathers to moult along the flanks to get in to full breeding plumage.

He seems to be quite attractive though as he has two ducks in tow. Here he is with one of them

The three juveniles from one of the breeding pairs of Great Crested Grebes. Two pairs have three young, one pair has two young, two pairs have a single juvenile each and another pair seems not to have attempted to nest. In the background you can see some of the extensive Canadian Waterweed (Elodea canadensis).

I know these leaves are from a Pedunculate (or Common, or English) Oak (Quercus robur). Unlike with the Horse-chestnut Leaf-miner (Cameraria ohridella) there is not one species of moth whose larvae specialise in oak leaves. Most of the moths involved are rarely seen as flying insects (imago). Anyway they mostly cannot be separated from other similar species. It is the shape of the mines and the host plants that identifies them most easily. Where is my 'I-Spy Leaf Mines' when I need it? These mines may be made by the Common Oak Midget (Phyllonorycter quercifoliella) but... To complicate matters there are also larvae of flies that mine leaves.

Another unidentified ichneumon sp.

The only hoverfly I saw today was this Marmalade Hoverfly (Episyrphus balteatus). It was of course inside the flower of Field Bindweed (Convolvulus arvensis).

This is the smaller of the two red flies that I commonly find on street lamp poles pre-dawn. It looks just like a scaled-down version of the larger one which I have assumed to be the Music fly Phaonia pallida. Since individual species of flies do not generally vary in size significantly I have no idea what this smaller species is.

Now I have 'got my eye in' I seem to be able to find these Yellow Swarming Flies (Thaumatomyia notata) most days. Here is one on a grass stem, dwarfed by a raindrop.

I have included another photo of a springtail Pogonognathellus longicornis-type because at the top of the frame is a tiny red-eyed fly. The springtail is about 6mm (¼") in body length which makes the fly about 3mm (⅛").

It is a while since I noted one of these bugs. It is a Common Green Capsid (Lygocoris pabulinus) and was also on one of the street lamp poles pre-dawn.

Despite its lurid appearance this is probably a Dusky Slug (Arion subfuscus), a species that comes in many shades of yellows and browns. Apparently you need to stroke them so you can see the colour of the mucus to be certain. I didn't.

To my untutored eye this looks exactly like a Field Mushroom (Agaricus campestris) and just like something you would buy in a shop. It was on the grass by the dam at the East end along with several others, at least one still in the ground. So it does not seem that it had fallen out of someone's shopping.

These large leaves belong to Winter Heliotrope (Petasites fragrans). Strangely I have never noticed the flowers that show from January through to March when little else is flowering.

Plane of the day. This is an Aero Commander 114B built in 1995. The design originated in 1972 as the Rockwell Commander 112. The design rights passed to Commander Aircraft of Norman, Oklahoma in 1988 who updated it. "Commander is the world's finest legendary single engine, high performance aircraft" - they say. The identity prefix 2- signifies it as registered in Guernsey. Many aircraft use this register as a 'flag of convenience', especially airliners owned by leasing companies while 'resting' between operators. This aircraft is somewhat different in that it was owned by a Guernsey-based company. It was offered for sale in July 2022 and if you have a spare £170,000...

(Ed Wilson)

------------------------------------------------------------------------------------------------------

The Flash: 09:30 – 10:20

(191st visit of the year)

Highlight today and probably the bird of the year for here was a juvenile Common Tern flying around and fishing. Almost certainly the bird seen since Saturday at the Balancing Lake (and see there earlier today). My previous sighting of this species here was on 15 July 2019. I believe that was only my second-ever record. Earlier sighting(s) predate 2012 when my computerised records commence. It is bird species #71 at The Flash for me in 2022.

Other bird notes:
- Most odd: there were two missing juvenile Great Crested Grebes again and the two I did see were nowhere near the adults. These were also well apart.
- Three House Martins were over the water at 10:05.

Birds noted flying over here:

None

Warblers noted:
- 3 Chiffchaffs: no song

Noted on / around the water
- 28 Canada Geese
- 3 + 4 (1 brood) Mute Swans
- 1 (1♂) Gadwall
- 23 (12♂) Mallard
- 1 (1♂) all-white duck (Aylesbury Duck)
- 12 (?♂) Tufted Duck only
- 15 Moorhens
- 29 Coots
- 2 + 2 (1 brood) Great Crested Grebes again
- 10 Black-headed Gulls: three of these first winter birds
- *1 Common Tern: juvenile, as highlighted
- 3 Cormorants

On / around the street lamp poles:
Nothing noted

Noted later:
- Common Wasp (Paravespula vulgaris)
- *Red Admiral (Vanessa atalanta): only my second species of butterfly here this year

Neither of these photos will win prizes. A record shot of what is just about recognisable as a tern.

This Red Admiral (Vanessa atalanta) was photographed through multiple layers of foliage. The main interest is that it has found the first, and as far as I could tell, the only open flower of the bank of Ivy near the academy. As more flowers open this will become the go-to location for late-flying hoverflies.

(Ed Wilson)

------------------------------------------------------------------------------------------------------

In the Priorslee Avenue tunnel:

- 1 owl midge Psychodidae sp.
- 13 other midges of various sizes again
- 4 White-legged Snake Millipedes (Tachypodoiulus niger)
- 1 Common Rough Woodlouse (Porcellio scaber)

(Ed Wilson)

------------------------------------------------------------------------------------------------------

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

Sightings from previous years without links are below

2013

Priorslee Lake

9 Ravens

(Ed Wilson)

2011

Priorslee Lake

1 immature Peregrine Falcon

Common Sandpiper

(Ed Wilson)

Nedge Hill

3 Wheatear

Yellow Wagtail

(John Isherwood)

Trench Lock Pool

1 Arctic Tern

(John Isherwood)

2010

Priorslee Lake

Albino Wood Pigeon

3 Swifts

1 Sedge Warbler

Redpoll

(Ed Wilson)

2007

Priorslee Lake

Kingfisher

(Ed Wilson)