19 Sep 22

Priorslee Lake and The Flash

11.0°C > 12.0°C: Started with very low cloud followed by a spell of drizzly rain. Cleared somewhat and a few bright spells before low cloud and light drizzle again. Almost calm. Good visibility but moderate in drizzle Very good later.

Sunrise: 06:50 BST

* = a photo from today

Priorslee Lake: 05:35 – 08:40

(201st visit of the year)

Bird notes:
- Another drake Eurasian Wigeon record.
- The single oldest juvenile Great Crested Grebe was still present today.
- No early roost dispersal of large gulls noted though visibility was poor.
- The Cormorant flew directly over without apparently looking at the lake.

Birds noted flying over here:
- no geese again
- 25 Wood Pigeons
- 1 Collared Dove
- 5 Lesser Black-backed Gulls
- 6 unidentified large gulls
- 1 Cormorant again
- 1 Jackdaw
- 47 Rooks

Hirundines etc. noted:
- 1 Barn Swallow

Warblers noted:
- 7 Chiffchaffs: two in song

Counts from the lake area:
- 2 + 4 (1 brood) Mute Swans
- 2 (1♂) Gadwall
- *1 (1♂) Eurasian Wigeon
- 11 (6♂) Mallard
- 2 (1♂) Tufted Duck: the drake flew off
- 10 Moorhens again
- 158 Coots
- 1 Little Grebe
- 10 + 10 (5 broods) Great Crested Grebes
- c.90 Black-headed Gulls: 66 of these were on the football field at 07:00
- 8 Lesser Black-backed Gulls
- 1 Grey Heron

Noted on / around the street lamp poles pre-dawn:
Still no moths (but at least there was one in the tunnel).
- *male and female ichneumon of different species
- usual array of flies and midges
- *1 owl midge Psychodidae sp. with plain wings again
- *1 Ectopsocus species of barkfly
- 1 springtail Pogonognathellus longicornis-type
- *1 Leiobunum blackwalli harvestman
- *1 Leiobunum rotundum harvestman

Noted later in the cloudy conditions:
- wasp sp.: too dull to photo to check the specific ID
- Grouse Wing caddis fly (Mystacides longicornis)
- Alder Leaf Beetle (Agelastica alni)
- Grey Squirrel (too many: at least seven seen)

Another visit by a drake Eurasian Wigeon.

Not quite enough light to 'freeze' the action as it wing-flaps. Note the obvious pale belly and the very rounded head as well as the overall orange tone.

Here the white in the forewing shows confirming it as a drake and an adult drake as that. First year drakes show a grey forewing. Ducks do not show this feature. The green area (the speculum) is brighter and larger on drakes.

Not much to go on here. As it has an ovipositor it is a female ichneumon but that is about all I can say.

This has no ovipositor so it is a male ichneumon. The longer and differently-shaped antennae suggest it is a different species.

Yet another small red / orange fly, this one with a banded abdomen. As usual I have no idea as to its identity.

This looks like another of the rather unusual presumed owl midges Psychodidae sp. with plain wings. As before its banded antennae seem rather longer than the usual species I see. Some idea of scale is given by the dark mark in the photo which is the bottom tip of the figure '3' of the street lamp's identity.

I think this is an Ectopsocus species of barkfly. There are two species in this group with dark spots in the wing of males: E. briggsi and E. petersi. Genitalia examination is the only way to separate them.

The all dark eyes on this harvestman makes it a Leiobunum rotundum harvestman. Almost within touching distance of its long legs was...

...this other harvestman. To my eyes there are white rims around its eyes and it is therefore a male Leiobunum blackwalli harvestman. Both these individuals show a globular body so both are males. Females of this group are more distinctive as the have differently shaped dark saddles.

 It is unusual to find new flowers at this time of year. Out with the PlantNet app. which tells me it is...

...Hedge Mustard (Sinapis arvensis). My Flora calls this species Charlock or Wild Mustard but like many wild flowers there are numerous vernacular names. Hedge Mustard flowers as late as October and is a widespread and pernicious weed that we have managed to introduce more or less throughout the New World. I think caution is advised over this identity. It was growing on the grass behind the dam and there must be a possibility that this an escape by one of the many varieties of the closely related Rape (Brassica napus). Rape has been grown in fields to the East of Castle Farm Way for many years.

(Ed Wilson)

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The Flash: 08:45 – 09:40

(197th visit of the year)

Bird notes:
- The drake Gadwall and some of the Mallard have done a disappearing trick again though the all-white Aylesbury-type remains.
- As yesterday only one adult Great Crested Grebe located. Also only three juveniles noted. Two of these had a flying race across the water. One 'kept one foot on the bottom' so as to speak. The other achieved lift-off and even managed a turn at the far end before pitching back in.
- Just the one Cormorant arriving. Perhaps they have eaten all the fish and have moved on.

Birds noted flying over here:
- 2 Lesser Black-backed Gulls

Warblers noted:
- 2 Chiffchaffs: no song

Noted on / around the water
- 25 Canada Geese: 20 of these arrived together
- 3 + 4 (1 brood) Mute Swans
- no Gadwall
- 30 (20♂) Mallard
- 1 (1♂) all-white duck (Aylesbury Duck)
- 11 (4?♂) Tufted Duck
- 13 Moorhens
- 28 Coots remain
- 1 + 3 (1 brood) Great Crested Grebes
- 17 Black-headed Gulls: at least five first winters
- 1 Cormorant: arrived
- 1 Grey Heron

On / around the street lamp poles:
Nothing noted

Noted later:
- Horse-chestnut Leaf-miner moth (Cameraria ohridella)
- Honey Bee (Apis mellifera)
- *Common Carder Bee (Bombus pascuorum)
- *ichneumon sp.
- *Common Green Shieldbug (Palomena prasina): second instar
- *Hawthorn Shieldbug (Acanthosoma haemorrhoidale)
- Alder Leaf Beetle (Agelastica alni)
- Grey Squirrel

Another photo of a Common Carder Bee (Bombus pascuorum), here on a rather late flowering Buddleia or Butterfly-bush (Buddleja davidii). Note the pollen on the rear leg of the bee.

This male ichneumon has antennae rather like the male I photographed at the lake. This is however a larger insect. And equally unidentified among the 2500 known species in Britain.

Yesterday I found an adult Common Green Shieldbug (Palomena prasina). Today here is a second instar nymph.

While this is a Hawthorn Shieldbug (Acanthosoma haemorrhoidale). This is from the new generation that will hibernate overwinter. It may darken somewhat but does not go brown in the same way that the Common Green Shieldbug does.

Finally something I found on the NatureSpot web site HERE, that sums up my view about the council's mania for mowing so much of our area so regularly. In my view Ricoh do a much better job by leaving their grassy area un-mown (though I'd like them to leave it un-mown somewhat longer).

(Ed Wilson)

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In the Priorslee Avenue tunnel:

- 1 Tipula paludosa cranefly
- 5 owl midges Psychodidae sp.
- 25 other midges of various sizes
- 3 White-legged Snake Millipedes (Tachypodoiulus niger)
- 1 Common Rough Woodlouse (Porcellio scaber)

(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

2011
Priorslee Lake
Common Sandpiper
(Ed Wilson)

2008
Priorslee Lake
Water Rail
129 Greenfinches leaving roost
(Ed Wilson)

2007
Priorslee Lake
Kingfisher
2 Redwings
(Ed Wilson)

2006
Priorslee Lake
4 Black-tailed Godwit
(Martin Adlam)