10 Sep 22

Priorslee Lake and The Flash

13.0°C > 16.0°C: Overcast overhead and to the West with clearer spells to the E. Cloud began to break after 07:00 with a few sunny periods. Light / moderate NNW breeze. Very good visibility.

Sunrise: 06:35 BST

* = a photo from today

Priorslee Lake: 05:25 – 09:20

(193rd visit of the year)

On another generally quiet morning the definite highlight was a juvenile Common Tern that spent a long while being elusive as it hawked up and down the water before eventually settling on one of the boat launching platforms. It is my 95th bird species here this year though I know that some of the fisherman have noted 'terns' previously which were likely this species.

Other bird notes:
- The annual Autumn increase in Coot numbers continues. Perhaps some have come from The Flash where there were fewer than usual noted later.
- I noted a single Barn Swallow out of the corner of my eye as it disappeared behind trees: could have been one of a larger group. Much later a group of six birds flew through.
- Sadly I think my comment some days ago that there were fewer Magpies evident seems to have been misplaced. 'Normal' numbers have resumed.
- Pre-dawn I heard a Song Thrush alarm-calling. My first record of this species here since 10 August.

Birds noted flying over here:
- 30 Canada Geese: 17 outbound together; 5 inbound together; 8 South together
- 1 Feral Pigeon
- 5 Stock Doves: three singles and a duo
- 94 Wood Pigeons
- 1 Collared Dove
- 1 Black-headed Gull again
- 1 Herring Gull again
- 34 Lesser Black-backed Gulls
- 3 unidentified large gulls
- 2 Jackdaws again
- 9 Rooks
- 2 Pied Wagtails again

Hirundines etc. noted:
- 7 Barn Swallows at least: see notes
- House Martin(s) heard only: busy with the tern at the time

Warblers noted (no song recorded unless specifically noted):
- 8 Chiffchaffs: two heard in song
- 4 Blackcaps

Counts from the lake area:
- *2 + 4 (1 brood) Mute Swans
- 11 (7♂) Mallard
- 7 Moorhens
- 141 Coots
- 1 Little Grebe
- ? Great Crested Grebes: not counted
- 83 Black-headed Gulls: 56 of these were on the football field at 06:40
- *2 Herring Gulls
- 1 Yellow-legged Gull
- 7 Lesser Black-backed Gulls
- *1 Common Tern: juvenile
- 1 Grey Heron
- 1 Kingfisher

Noted on / around the street lamp poles pre-dawn:

- *1 Angle Shades moth (Phlogophora meticulosa) in a Walnut Orb Weaver (Nuctenea umbratica) spider's jaws
- 1 cranefly likely Tipula paludosa
- *1 unidentified fly
- 1 Paroligolophus agrestis harvestman

Noted later:

Wasps:
- Common Wasp (Paravespula vulgaris)

Hoverflies
- *Broad-banded Epistrophe (Epistrophe grossulariae)
- *Common Dronefly (Eristalis tenax)

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

Bugs:
- 7 Spot Ladybird (Coccinella 7-punctata)
- Common Froghopper (Philaenus spumarius)

Beetles:
- *unidentified leaf beetle sp.
- *Alder Leaf Beetle (Agelastica alni)

Harvestman:
- *female Leiobunum rotundum harvestman

Fungus:
- *fairy ring fungus, possibly Fairy Ring Champignon (Marasmius oreades)

Mammals
- Grey Squirrel

This juvenile Mute Swan caught me unawares and I could not fit the fully stretched wing in the frame. This partly open shot shows the flight feathers are just about fully grown and we can expect to see it making attempts to fly within a week or so.

A juvenile Herring Gull. Very intricately marked when you get this close.

A size comparison with an adult winter Black-headed Gull.

I spent a long while trying to get decent photos of this tern. It initially seemed to what to spend all its time at the other end of the lake. The dark bar on the front edge of the wing indicates this is a juvenile but separation of Common and Arctic tern is never easy. The darker outer part of the wing suggests Common Tern.

Another equally distant shot confirming the wing shading.

Trying to get a decent exposure when the bird is flying against trees is difficult. Here the bill looks reddish.

Eventually it decided to land on one of the boat launching platforms amongst Black-headed Gulls. Here the bill looks all black.

A useful size comparison with an adult winter Black-headed Gull. Had it been an Arctic Tern the legs would have been much shorter – they almost look legless when perched.

It's a tiring life.

By careful approach I was able to get much closer without spooking any of the birds.

Really close. That bill is definitely all-black.

Two for the price of one. The spider is a Walnut Orb Weaver (Nuctenea umbratica) and its unfortunate prey is an Angle Shades moth (Phlogophora meticulosa).

This hoverfly is a Broad-banded Epistrophe (Epistrophe grossulariae).

A Common Dronefly (Eristalis tenax) searching for any nectar in one of the few remaining and rather sad-looking Common Ragwort (Jacobaea vulgaris) flowers.

I have no idea what this species of fly this is only that it has very red eyes and is rather dumpy. The speckling is likely to be dew rather than markings on the abdomen. It was on a street lamp pole pre-dawn.

And another unidentified and different-looking fly seen later.

Here is an attractively-marked small beetle. I have not been able to identity it. It looks somewhat like a small ladybird though the grooved wing cases do not support that view. It must be a leaf beetle.

This much larger beetle with the blueish gloss is an Alder Leaf Beetle (Agelastica alni).

The shape of the dark marking on the abdomen identifies this as a female Leiobunum rotundum harvestman. Note it has lost a leg somewhere.

It has not taken long for the fungus to respond the rain. Here is one of a number of fairy rings I noted.

A close up of a few of the fruiting bodies, which may be Fairy Ring Champignon (Marasmius oreades). I read that the genus name Marasmius comes from the Greek word marasmos, meaning 'drying out'. This group of fungus can tolerate drought. As soon as it rains again not only do they regain their previous shape but they are capable of resuming releasing new spores. They contain the sugar trehalose, which prevents catastrophic cell damage when the fruit-bodies become desiccated.

Aircraft of the day. This is Partenavia P68B Victor, an Italian design often used for low-level photo-mapping. The UK Police use a number for surveillance. The undercarriage has no need to be retractable for such operations. The PH- part of the registration indicates a Dutch origin. It is registered to Holding Y.E. Slagboom BV. So there.

(Ed Wilson)

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The Flash: 09:25 – 10:20

(189th visit of the year)

Generally a quiet morning.

Bird notes:
- Probably more Canada Geese than I could see. I heard a group flying in some 10 minuted before I arrived and some of these were likely hidden inside the island.
- A second adult Great Crested Grebe put in appearance, both adults were with three begging juveniles. The fourth juvenile pattered in later. Was the recently missing adult perhaps sitting on another clutch of eggs? And if so what has happened to them?
- More Coots seem to have moved out.

Birds noted flying over here:
None

Warblers noted:
None

Noted on / around the water:
- >33 Canada Geese: most of these had arrived
- 3 + 4 (1 brood) Mute Swans
- 1 (1♂) Gadwall
- 23 (13♂) Mallard
- [the all-white duck (Aylesbury Duck) not seen]
- 12 (?♂) Tufted Duck
- 15 Moorhens
- 29 Coots only
- 2 + 4 (1 brood) Great Crested Grebes
- 4 Black-headed Gulls: no first winters
- 7 Cormorants again
- 1 Grey Herons

Noted on / around the street lamp poles:
- *1 Flame Carpet moth (Xanthorhoe designata)

Noted later:
- *Horse-chestnut Leaf-miner moth (Cameraria ohridella)
- Honey Bee (Apis mellifera)
- *Fat Hen (Chenopodium album): I remembered to photograph it!
- *unidentified fungus
- Grey Squirrel

The highlight for me here was finding this tiny moth. It is a Horse-chestnut Leaf-miner moth (Cameraria ohridella) and, as its name implies, the larvae are responsible for the brown patches shown to the right of the moth. The larvae feed on the cellulose between the surfaces of the leaves. This moth was first discovered in Macedonia in 1985 and first noted in the UK in 2002 near London. It is now abundant throughout the UK. Many trees, large and small, have most leaves affected to some degree. It is not thought to have a significant effect on the health of the tree.

A Flame Carpet moth (Xanthorhoe designata) on a street lamp pole in squirrel alley.

I did remember to photograph the Fat Hen (Chenopodium album) today. The leaf-shape precludes it being any other member of the genus.

I isolated the 'flowers' against a dark background. I will check whether the flowers open more than shown here.

This is a bit odd. This looks like a bracket fungus but was growing in the grass at the top end.

(Ed Wilson)

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In the Priorslee Avenue tunnel:

- unidentified fly sp.
- *2 species of cranefly, likely Tipula paludosa and T. confusa.
- 2 owl midges Psychodidae sp.
- 17 other midges of various sizes
- *1 unidentified fly
- 4 White-legged Snake Millipedes (Tachypodoiulus niger)
- 1 Common Rough Woodlouse (Porcellio scaber)

Another unidentified species of fly. It also appears unusually rather squat. It is also distinctly hairy.

Another example of what is likely to be the cranefly Tipula paludosa. A female and unlike the one I photographed yesterday the wings look the right way around. Many craneflies rest with their wings apart like this, but...

...some rest with their wings folded. This is likely T. confusa. The tip of the abdomen is not visible so the sex cannot be determined from the photo.

(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
Nedge Hill
2 Wheatear
2 Yellow Wagtail
1 Raven 
(John Isherwood)

Priorslee Lake
Common Sandpiper
Wheatear
(John Isherwood)

2010
The Flash
Common Sandpiper
(Ed Wilson)

2008
Priorslee Lake
2 Kingfisher
(Ed Wilson)

2007
Priorslee Lake
Pochard
Common Gull
(Ed Wilson)

2005
Priorslee Lake
A juvenile Arctic Tern
(Ed Wilson)