11 Sep 26

Priorslee Balancing Lake and The Flash

14.0°C > 17.0°C: Clear early. More cloud after c.08:15 still with sunny intervals. Light westerly breeze. Very good visibility.

Sunrise: 06:36 BST

* = a species photographed today
! = a first sighting of the species this year
$ = a new species for me in this area

Priorslee Balancing Lake: 05:10 – 09:10

(205th visit of the year)

Bird notes:
- a small arrival of Canada Geese.
- still just a single Mute Swan.
- a Common Sandpiper flushed off the concrete ramp c.06:10 and then what I assume was the same bird, flushed off the North side c.07:30.
- c.80 Black-headed Gulls flew in on a more traditional flightpath – low from the West – at c.05:55. Eventually c.150 were present which was the number I noted on the football field c.06:45 when something spooked them and only 49 returned.
- it appears that as soon as any Lesser Black-backed Gull is prepared to settle on the water all the erstwhile flying over birds decide it is safe for them to visit as well. I estimated 180 arrived by 06:15, also from the West.
- a single Grey Heron flew West at 08:00. Another, in addition the bird at the lakeside, flushed off the football field c.09:05.
- a single Swift was very briefly over the North wood at 06:30. Later two were over the Castle Farm Way area after c.08:00.
- the first hirundines were seen high over at 06:20 but could not be identified – too high to hear any calls. Later I noted at least two Sand Martins (an unusually late date), >30 Barn Swallows and at least five House Martins over the water after 08:00.
- another high count of Chiffchaffs with six of the 15 singing.
- a single calling Blackcap.

Bird(s) noted flying over here:
- 17 Canada Geese: a duo flew East; 15 flew south-west together
- 14 Lesser Black-backed Gulls
- 1 Grey Heron
- 11 Wood Pigeons only
- 197 Jackdaws
- 128 Rooks

Counts from the lake area:
- 7 Canada Geese: arrived as a quintet and two singles
- 1 Mute Swan again
- 39 (?♂) Mallard
- 6 (1♂?) Tufted Duck
- 6 Moorhens
- 55 Coot
- 19 Great Crested Grebes
- 1 *Common Sandpiper
- >150 Black-headed Gulls
- >5 Herring Gulls
- >180 Lesser Black-backed Gulls
- 2 Grey Heron

Hirundines etc. noted:
- 3 *Swifts
- >2 Sand Martins
- >30 *Barn Swallows
- >5 House Martins

Warblers noted:
- 15 Chiffchaffs: of these six in song
- 1 Blackcap

Also noted:
Very little in now cloudy conditions.

Bees, wasps etc.:
- Common Wasp Vespula vulgaris

Flies:
- Greenbottle Lucilia sp.
- Flesh fly Sarcophaga sp.
several other unidentified flies.

Thanks to Martin Adlam I now have a satisfactory identification of yesterday's moth. It was a very plain-looking example of a Sallow Cirrhia icteritia.

On the West end street lamp poles around dawn:

Moths:
- 1 ! *Garden Rose Tortrix Acleris variegana

Bees, wasps etc.:
- 1 Common Wasp Vespula vulgaris

Flies:
- 1 female plumed midge Chironomus plumosus

Springtails:
- 1 *springtail Pogonognathellus longicornis-type

Spiders, harvestmen etc.:
- 1 *Bridge Orb-web Spider Larinioides sclopetarius [Bridge Orbweaver]

Mammals:
- a single pipistrelle-type bat was flying above the south-west grass c.05:55.
- one Noctule-type bat was flying high over c.06:00.

Terrible photo as I flushed a Common Sandpiper – the leading bird here. I saw two birds out of the corner of my eye and assumed they were both sandpipers. The photo tells me otherwise, the second bird being a Barn Swallow.

I remain surprised to still be seeing Swifts at this date.

Micromoths at the top of street lamp poles are usually difficult to ID. This mainly black and white species is an exception. It is the very common Garden Rose Tortrix Acleris variegana: moth species #68 here this year for me. I remain well down on the number of moth species seen here this year.

A springtail Pogonognathellus longicornis-type.

This Bridge Orb-web Spider Larinioides sclopetarius is eating its breakfast. No idea what though.

(Ed Wilson)

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In the Priorslee Avenue tunnel:

Moths:
none

Four-winged flies:
- 1 Common Green Lacewing Chrysoperia carnea

True flies:
- 8 midges
- 1 cranefly Limonia nubeculosa
- 1 ! *midge Psectrotanypus varius
- 1 moth fly Psychodidae sp. [Drain Fly or Owl Fly]

Arthropods:
- 1 Common Shiny Woodlouse Oniscus asellus

Spiders, harvestmen etc.:
- 1 Long-jawed Orb-web Spider Tetragnatha sp.
- 7 *Missing Sector Orb-web Spider Zygiella x-notata [Silver-sided Sector Spider]

A distinctive midge that goes by the name Psectrotanypus varius. After much searching on the internet I discovered that "the genus name refers to the comb-like structures on the larval mentum". So now we know! I also discovered that positive identification to the species-level "requires examination of male genitalia and larval mouthpart structures" [thanks to bugswithmike.com].

One of the many Missing Sector Orb-web Spiders Zygiella x-notata showing how it got the alternative name of Silver-sided Sector Spider. The "missing sector" is because the usual orb-web has one section without cross-strands. In the tunnel the spiders do not seem to make proper webs and it is difficult to illustrate this. It is also difficult to photograph them as they are usually close to the wall or ceiling and the camera has difficulty distinguishing between the real thing and the shadow cast by my torch.

(Ed Wilson)

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The Flash: 09:15 – 10:15

(202nd visit of the year)

Bird notes:
- six Mute Swans again.
- yesterday's Tufted Duck apparently all departed.
- eleven brownhead Goosander today.
- two adult and all four juvenile Great Crested Grebe present with one of the adults at the opposite end of the water and one of the juveniles frequently some distance apart from its siblings. The immature bird seen again, hiding in an inaccessible cut-off behind one of the out-of-bounds bridges.

Bird(s) noted flying over here:

None

Noted on / around the water:
- 67 Canada Geese: of these 38 arrived in four groups
- no Greylag Geese
- 6 Mute Swans
- 29 (20?♂) Mallard
- no Tufted Duck
- 11 (0♂) Goosander
- 9 Moorhens
- 24 Coot
- 3 + 4 (1 brood) Great Crested Grebe
- 13 Black-headed Gulls
- 7 Cormorants: of these two arrived
- 3 Grey Herons

Warblers noted:
- 2 Chiffchaffs: no song

Noted around the area:

Moths:
- 1 Chevron Grass Moth Agriphila geniculea [was Elbow-stripe Grass-veneer]

Bees, wasps etc.:
- 4 *Honey Bees Apis mellifera
- 2 Buff-tailed Bumblebees Bombus terrestris
- >5 Common Wasps Vespula vulgaris

Hoverflies:
- 1 *Syrphus sp.

True flies:
- Greenbottle Lucilia sp.
- Flesh fly Sarcophaga sp.
various other unidentified flies of at least four species

Beetles:
- 1 7 Spot Ladybird Coccinella 7-punctata

A Honey Bee Apis mellifera tucks in.

A Syrphus species of hoverfly. A female but as the hind legs are not visible to check the pattern of dark and light I cannot determine the species.

(Ed Wilson)

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2013
Priorslee Lake
2 Snipe
Wheatear
3 Raven
(John Isherwood/Ed Wilson)

2010
Priorslee Lake
1 Hobby
1 Sedge Warbler
3 Swift
2 Teal
1 Meadow Pipit
(John Isherwood)

2008
Priorslee Lake
Black Tern
Kingfisher
(Ed Wilson)

2007
Priorslee Lake
Kingfisher
(Ed Wilson)