Friends of Priorslee Lake Wildlife Site: 2 Oct 26

Priorslee Balancing Lake and The Flash

12.0°C > 14.0°C: Broken cloud. A light shower c.06:00. A few sunny intervals later. Moderate south-easterly wind veering southerly. Very good visibility.

Sunrise: 07:13 BST

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

Priorslee Balancing Lake: 05:45 – 09:10

(222nd visit of the year)

Bird notes:
- a pair of Mute Swans. These departed to the East 08:45 but were presumably the pair that arrived from the East a few minutes later.
- a Little Grebe seen again, briefly along the south side.
- Lesser Black-backed Gulls started arriving with inbound calling birds heard overhead before 06:00. I was doing reasonably well in keeping count of arrivals, albeit they were hard to spot early on. My count had just reached 450 when a huge arrival of at least 200 more in company with at least 450 Black-headed Gulls confused the issue. So at least 650. Many of these birds soon departed to the East making it impossible to tell whether, as there had been yesterday, there was any passage to the East.
- I visited the football field c.07:25 when at least 350 Black-headed Gulls were feeding and moving around on the grass – at least they were until three sparring Sparrowhawks appeared overhead. I noted no other gull species on the field.
- apart from a few Black-headed Gulls all the gulls had departed by 07:45.
- later I logged 2 Herring and 103 Lesser Black-backed Gulls arriving from the East, possibly birds returning. There was a minuscular passage of gulls overhead.
- five Chiffchaffs noted: no song.

Bird(s) noted flying over here:
- 16 Canada Geese: flew East together
- 1 Greylag Goose: flew West
- 2 Herring Gulls again
- 14 Lesser Black-backed Gulls
- 1 Cormorant
- 1 Grey Heron
- 3 Sparrowhawk
- 30 Wood Pigeons
- 1 Skylark
- 259 Jackdaws
- 150 Rooks exactly
- 1 Pied Wagtail again
- 1 Chaffinch

Counts from the lake area:
- 2 Mute Swans
- 14 (9♂) Mallard
- 6 (2?♂) Tufted Duck
- 7 Moorhens
- 36 Coot
- 1 Little Grebe
- 11 *Great Crested Grebes
- >450 Black-headed Gulls: see notes
- 2 Herring Gulls again
- >600 *Lesser Black-backed Gulls: see notes
- 2 *Cormorants: arrived separately
- 1 Grey Heron
- 1 Kingfisher again

Warblers noted:
- 2 Chiffchaffs: of these one in song
- 1 Blackcap: calling only

Also noted:
Very little. Stayed mostly dull.

Bees, wasps etc.:
- Common Wasp Vespula vulgaris
these all annoying me pre-dawn as I tried to count the gulls arriving

True flies:
- cranefly Tipula confusa
not a single other fly seen

On the West end street lamp poles before dawn:
The light shower while I was at the lamps no doubt affected the numbers as did the brisk wind.

True flies:
- 1 *female plumed midge Chironomus plumosus
- 1 wood gnat Sylvicola sp.
- 1 *unidentified fly

Beetles:
- 2 Cabbage-stem Flea Beetle Psylliodes chrysocephala

Spiders, harvestmen etc.:
- 1 unidentified spider
- 1 harvestman Paroligolophus agrestis

The sunrise just starting to colour. The specs above the distant trees are Black-headed Gulls leaving for the football field.

An expanse of colour developed.

Intensifying as the sun was about to rise.

As the sun did so the contrast became too great for my phone camera to handle and the "big camera" came to the rescue.

An adult Great Crested Grebe in threat posture. Several of the families have now dispersed with the remaining three families tending to use much of the lake rather than stick to the area close-by their nest site. Occasional conflicts occur.

An adult Lesser Black-backed Gull. Usually the outer wing looks darker than the inner wing and I am not sure why that is not true here. What is obvious is that it has not quite completed its annual wing moult with the outer primary still growing.

It is the leasing bird here. The trailing bird has developed more extensive winter head-streaking. The strength of the streaking is variable and seems unexplained. A theory that older birds have more streaking has been debunked recently. What this bird also shows is a very ragged edge to the secondary feathers suggesting it too is still in moult.

Another variation. On this bird the outer three primaries have yet to be dropped with primaries #4 and #5 still growing. The secondaries on this bird are all in a neat line.

The same bird from underneath.

The Cormorant on the right had just finished swallowing a fish for breakfast. I thought it was about to usurp the one on the buoy. Not so. It was obviously still hungry and went off in pursuit of more fish.

"I've seen him off" Standing on the buoy looks a risky business.

One of the trio of Sparrowhawks over the football field c.07:25. Note the broad and rounded wings as well as the long tail - allowing exceptional manoeuvrability when chasing small birds.

Two of them sparring. Males and female are of very different size from which I deduce these are the same sex. I would not like to hazard a guess as to which.

A side-elevation view of a female (hence no plumes) plumed midge Chironomus plumosus.

An unidentified fly on a street lamp pole pre-dawn. There seem to be numerous fly species with brown at the base of the wings. I asked Mr. Google why this is so. Seems he does not know as the suggestions were mainly about butterfly wings! The closest I can get is the Noon Fly Mesembrina meridiana , one of the Muscid family. However that is both a more robust species and, as its vernacular name implies, mostly seen inactive, resting on fences etc. in the midday sun.

(Ed Wilson)

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In the Priorslee Avenue tunnel:

Moths:
- 1 *Rusty-dot Pearl Udea ferrugalis : presumed same as yesterday

True flies:
- 22 midges of at least three species
- no moth fly Psychodidae sp. [Drain Fly or Owl Fly]

Arthropods:
- 3 White-legged Snake Millipede Tachypodoiulus niger
- 2 Common Rough Woodlouse Porcellio scaber

Spiders, harvestmen etc.:
- 4 Missing Sector Orb-web Spiders Zygiella x-notata [Silver-sided Sector Spider]

The only moth of the day (as it had been yesterday) was this Rusty-dot Pearl Udea ferrugalis.

I am bemused by this. About twice the length of any millipede I have seen here. It also appears to have no legs as if it might be a slug or a worm. I am wondering whether it is just a felt-top pen scribbling though it did not seem connected to any of the other messages scrawled on the wall.

(Ed Wilson)

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The Flash: 09:15 – 10:30

(219th visit of the year)

Bird notes:
- only two of the four "static" Canada Geese noted. 22 more arrived together
- I could only find five Mute Swans. This seemed to included "billy-no-mates" who is often tricky to spot.
- yesterday's Tufted Duck gone [not the additional birds at the Balancing Lake as no drakes were seen yesterday].
- *a drake Goosander with at least 44 brownheads. They were everywhere and sitting inside the island. Probably more.
- one full adult Great Crested Grebe was seen with two juveniles. A third juvenile has declared UDI and was at the top end.
- still five Little Egrets.

Bird(s) noted flying over here:
- 1 Jackdaw

Noted on / around the water:
- 24 Canada Geese: of these 22 arrived together
- 10 Greylag Geese: arrived together
- 5 Mute Swans: see notes
- 29 (18♂) Mallard
- no Tufted Duck
- 45+ (1♂) *Goosander: see notes
- 6 Moorhens
- 21 Coot
- 1 + 3 (1 brood) Great Crested Grebe: see notes
- 31 Black-headed Gulls
- 1 Herring Gull: near adult, briefly
- 5 Cormorants again
- 3 Grey Herons
- 5 Little Egrets again

Warblers noted:
- 1 Chiffchaff: no song

Noted around the area:
A short burst of sun tempted a few things out:

Butterflies:
- 1 *Speckled Wood Pararge aegeria

Bees, wasps etc.:
- 1 Honey Bee Apis mellifera
- >10 *Common Wasp Vespula vulgaris

Hoverflies:
- 2 Tapered Dronefly Eristalis pertinax [Tapered Drone Fly]
- 1 *Common Dronefly Eristalis tenax [Common Drone Fly]
- 1 *Wasp Plumehorn Volucella inanis [Lesser Hornet Hoverfly]

Other true flies:
- 1 "bluebottle" Calliphora sp.
- 1 Muscid fly Phaonia sp.
- 1 *root-maggot fly sp.
several other species of fly even less identified

Beetles:
- 1 7 Spot Ladybird Coccinella 7-punctata

A brownhead Goosander among a patterned water-scape.

And here a brownhead with the only obvious drake. These have such contrasting plumage that even when there is no sun it is difficult for the camera to show clearly.