6 Aug 21

Priorslee Lake and The Flash

14.0°C > 16.0°C: Early showery and occasionally heavy rain gave way to brighter and even sunny spells after 07:30. Another shower by 09:15. Light SSE wind. Moderate visibility in rain, otherwise good.

Sunrise: 05:36 BST

* = a photo today

Priorslee Lake: 05:15 – 06:00 // 06:55 – 09:25

(167th visit of the year)

A delayed start due to rain

Bird notes:
- At least 170 Wood Pigeons were put up far to the N c.07:45. None of the unusually large number logged flying over were directly related to this panic though I am sure that some were making their way to or from the same feeding area.
- The two juvenile Great Crested Grebes from the first-hatched brood are behaving rather unusually. I have yet to hear them begging unless an adult appears close-by with a fish – usually they are audible as soon as I get near the lake and call incessantly: and they are freely diving, though whether they have worked out how to catch fish is a moot point. The second pair to hatch juvenile(s) have yet to put their sole surviving youngster on to the water.
- Two Sparrowhawks (male and female, ages not determined) were circling over the football field at 05:55. Strangely the Black-headed Gulls on the field took no notice.

Overhead:
- 109 Canada Geese: 107 outbound in five groups; duo inbound
- 29 Greylag Geese: 29 outbound in three groups
- 166 Wood Pigeons: see notes
- 5 Black-headed Gulls
- 1 Herring Gull
- 1 Lesser Black-backed Gull
- 2 Sparrowhawks
- 1 Jackdaw yet again
- 2 Rooks
- 2 Ravens again

Hirundines etc., noted:
- 4 House Martins

Warblers noted: not too much should be read in to the lower numbers of some species – soaking wet undergrowth limited my exploration.
- 11 Chiffchaffs
- 1 Sedge Warbler again
- 2 Reed Warblers
- 4 Blackcaps

Count from the lake area:
- 2 + 4 (1 brood) Mute Swans
- 7 (?♂) Mallard
- *2 (2♂) Tufted Ducks
- 1 + 2 (2 broods) Moorhen
- 47 Coots: adults and immatures
- 6 + 3 (2 broods) Great Crested Grebes still
- 93 Black-headed Gulls: at least two juveniles
- 7 Lesser Black-backed Gulls: five immatures; all on the football field c.05:40 only'
- 2 Cormorants: arrived and departed separately again
- 1 Grey Heron

Street lamps
Not checked as heavy rain made it pointless

Sailing club shelter
Not visited pre-dawn:

Things seen later:

NB: Thanks as ever to Nigel I can report that yesterday's unidentified harvestman was another Dicranopalpus sp. sitting at an unusual angle. Incidentally I will now record what I have previously referred to as Dicranopalpus ramosus agg. as Dicranopalpus sp. as there are now known to be three (not two) species in the genus resident in the UK. None is separable from photos.

Moths:
- *Cinnabar caterpillar (Tyria jacobaeae)
- *Snout (Hypena proboscidalis)

Bees / Wasps etc.:
- Garden Bumblebee (Bombus hortorum)
- *Red-tailed Bumblebee (Bombus lapidarius)
- Common Wasp (Paravespula vulgaris)

Hoverflies:
- *Plain-faced Dronefly (Eristalis arbustorum)
- Common Dronefly (Eristalis tenax)
- *Chequered Hoverfly (Melanostoma scalare)
- *Common Twist-tail (Sphaerophoria scripta) [was Long Hoverfly]

Damselflies:
- Common Blue Damselfly (Enallagma cyathigerum)

Other flies:
- *probable Greenbottle Lucilia ampullacea
- *Semaphore fly (Poecilobothrus nobilitatus)
- *Unidentified gnat species

Bugs:
- *Mirid bug, perhaps Plagiognathus arbustorum

Molluscs:
- White-lipped Snails (Cepaea hortensis) as ever
- *Black Slug (Arion ater group)

Fungus:
- *Fairy Ring Champignon (Marasmius oreades)

Flowers new for the year
- *Oxford Ragwort (Senecio squalidus)

One of the two drake Tufted Ducks on the water this morning. Still some white on the flanks: soon the flanks will be all grey as it moults, making separation of the sexes hard for the next few months. Note the 'tuft' is rather wispy. Join the club.

An easy one: a Cinnabar moth caterpillar (Tyria jacobaeae) on its favourite (only?) food-plant Common Ragwort (Jacobaea vulgaris).

I did not expect to see any moths in the wet conditions so I was surprised to flush this Snout moth (Hypena proboscidalis). Sadly it hid its 'snout' under a leaf and I knew if I moved position it would likely fly away never to be seen again. Correct!

A very soggy-looking bumblebee. In the field I thought it was all black: in the photo it is just possible to make out a red tail so it is a Red-tailed Bumblebee (Bombus lapidarius).

Here is another Red-tailed Bumblebee: not quite as soggy. I noted how challenging it was to photograph this species as they are normally very restless. Today its activity was dampened like its fur.

I am going with Plain-faced Dronefly (Eristalis arbustorum) for this hoverfly. In my (limited) experience this is a much more difficult member of the group to approach to check that it has a completely pale face. The markings on the abdomen are variable and similar to other Eristalis sps. This is a rather stocky-looking member of the tribe.

"I like your style". A Chequered Hoverfly (Melanostoma scalare) compliments a Larger Bindweed flower (Calystegia Sepium).

This has to be a male Common Twist-tail (Sphaerophoria scripta) [was Long Hoverfly] though it caused me to pause. I rarely see this species with its wings closed. The markings visible show narrower and slightly more downward curving yellow band than usual. However the fact that the body extends beyond the folded wings rules out any other species in the family.

Is this a Greenbottle or a Bluebottle? I read that the Greenbottle Lucilia ampullacea can retain blue colouration and while not a definitive feature is a good clue.

This small fly with a brassy green and orange thorax and antennae thickened at the base seems to be a female Semaphore fly (Poecilobothrus nobilitatus). Males have white tips to their wings. I hesitate over its identity because there were dozens of these, all female. So?

Did I say small? This is even smaller. One of many gnats / midges that are constantly around. This one was caught in a web allowing a decent view. Cannot ID it though.

This Mirid bug is perhaps Plagiognathus arbustorum. Apart from being a good match in shape, colouration and (mainly lack of) markings a feature of this species is the black on the hind femur. Another insect that is feeding on Common Ragwort.

Despite appearances this is most likely from the Black Slug (Arion ater) group. These can be black, brown, grey, green, yellow, orange – you get the idea. There are thought to be up to four species involved with colour not a determinant. Indeed DNA work suggests there are many hybrids.

I fouled up the photo of the flowers of this Oxford Ragwort (Senecio squalidus) and in case I forget to take them again here are the distinctive leaves. The flower heads of this plant are smaller and more well-separated than Common Ragwort and are only just appearing while some Common Ragwort is beginning to go to seed.

The grass on top of the dam shows a clear area of longer grass that is also a brighter green. This is typically the result of one of many species of fungus. These fungus feed on dead material – in this case the discarded grass cuttings that are left after the mowing – and in doing so release nitrogen in to the soil, giving the living grass a boost. Over many years the rings tend to get bigger as the fungus spreads its mycelium outwards.

Here is one group of fungus in the ring. These look like Fairy Ring Champignon (Marasmius oreades) though there are other possibilities.

Another group. They do not look very appetising though if I have identified them correctly then they are reported as edible. Before the academy running track was created the grass used to have Field Mushrooms (Agaricus campestris) in fairy rings in early Summer which I ate on numerous occasions. I never saw any fairies.

(Ed Wilson)

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Between the lake and The Flash:

A surprise was a Reed Warbler sub-singing beside the lower pool. Could be a local bird exploring or a migrant passing through. As far as I can recall this in my first around the pools – I have certainly had Sedge Warbler on Spring passage.

(Ed Wilson)

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In the Priorslee Avenue tunnel:

- 2 Single-dotted Wave moths (Idaea dimidiata)
- 1 Marmalade Hoverfly (Episyrphus balteatus): I suppose they have to roost somewhere!

Spiders
Not recorded

(Ed Wilson)

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The Flash: 06:05 – 06:50

(152nd visit of the year)

The rain was at its heaviest while I was here and may have affected some numbers.

Bird notes:
- A duck Mallard with two ducklings was by the island. She was briefly joined by a drake and I thought another two ducklings appeared. The drake soon moved away and I never saw more of any other ducklings.
- All four Tufted Duck ducklings confirmed as still doing well, staying close to mum.
- Unusual was a Stock Dove calling from the roof of Priorslee Academy.
- Another adult Great Crested Grebe emerged and was seen to have at least one juvenile on its back.

Birds noted flying over here:
- 2 Wood Pigeons

Hirundines etc., noted:
None

Warblers noted:
- 6 Chiffchaffs

On /around the water:
- 16 Canada Geese
- 3 Greylag Geese
- 3 + 2 (1 brood) Mute Swan
- 52 (?♂) + 2? (1 brood) Mallard: see notes
- 32 (?♂) + 4 (1 brood) Tufted Duck
- 4 + 4 (3 broods) Moorhens
- 7 juvenile Coots (4 broods)
- 2 + 1? (1 brood) Great Crested Grebes
- 1 Black-headed Gull only: not a juvenile
- 1 Grey Heron again

On various lamp poles:
- 2 Dicranopalpus sp. harvestmen again

(Ed Wilson)

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On this day
2020
Priorslee Lake
Today's Sightings Here

2019
Priorslee Lake
Today's Report Here

2015
Priorslee Lake
Today's Sightings Here

2012
Priorslee Lake
Green Sandpiper
(Ed Wilson)

2011
Nedge Hill
1 (imm/fem) Common Redstart
(John Isherwood)

2009
Priorslee Lake
Dunlin
(Ed Wilson)

2006
Priorslee Lake
2 Common Tern
(Merv)