24 Jun 19

Priorslee Lake, The Flash, Trench Lock Pool and Trench Middle Pool

Priorslee Lake:  04:10 – 05:45 // 06:35 – 06:40 // 08:35 – 09:10
The Flash:  05:50 – 06:30
Trench Lock Pool:  06:50 – 07:00 // 07:50 – 08:25
Trench Middle Pool:  07:05 – 07:45

14.0°C > 16.0°C:  Low overcast. Almost calm. Murky with distinctly moderate visibility.

Sunrise: 04:45 BST again

Another earlier than usual visit to Trench with split visits to the lake.

Priorslee Lake:  04:10 – 05:45 // 06:35 – 06:40 // 08:35 – 09:10

(158th visit of the year)

Bird notes from today
- Two Tufted Duck flew off E 05:10 – not sexed before they left.
- Early on five adult Great Crested Grebes were seen with two well-grown juveniles (so where was the other juvenile yesterday?). These seemed to comprise the parents of these juveniles; the recently arrived pair; and one of the pair from the NW with its partner assumed to be brooding the new juveniles in the reeds. Later this bird was present, still with an unknown number of juveniles on its back, with one of the recently arriving pair missing / hiding.
- Two adult Black-headed Gulls in heavy wing-moult flew E at 05:15. One had also completely lost its tail.
- Single Swift flew over at 04:30. No more until four at 05:15: these gone by 06:35 and no more seen.
- Two Grey Wagtails seen flying off from dam. First here for me since 30 April.
- Adult Pied Wagtail seen collecting food from SW grass area: must be feeding second brood.

Bird totals:

Birds noted flying over or flying near the lake:
*** numbers affected by poor visibility ****
- 1 Grey Heron
- 2 Black-headed Gulls
- 1 Feral Pigeon
- 2 Stock Doves
- 11 Wood Pigeons
- 13 Jackdaws
- 4 Rooks

Hirundines etc. noted:
- 5 Swifts only

Warblers noted (singing birds):
- 7 (7) Chiffchaffs
- 17 (16) Blackcaps
- 3 (2) Garden Warblers once more
- 1 (1) (Common) Whitethroat
- 1 (1) Sedge Warbler
- 5 (5) Reed Warblers

Counts from the lake area:
- 2 + 6 (1 brood) Mute Swans
- 10 (8♂) Mallard
- 2 (?♂) Tufted Duck
- >5 + >2 (2 broods) Great Crested Grebes (see notes)
- 3 + 1 (1 brood) Moorhens
- 26 + 24 (7? broods) Coots
- 1 Lesser Black-backed Gull

On the lamp poles pre-dawn:
- Yesterday’s carpet moth that eluded identification still present and still eluding identification.

Seen later:
- 1 noctule-type bat flying around again
- 1 Fox
- Very many moths flushed from the grassy areas early on. Unable to see where any of them ‘collapsed’ in to the vegetation to attempt an ID
also
- First flowers here this year of Broad-leaved Willowherb (Epilobium montanum)

(Ed Wilson)

------------------------------------------------------------------------------------------------------

The Flash:  05:50 – 06:30

(151st visit of the year)

Notes from here:
- The cygnets are already declaring UDI and are frequently well away from either parent and, sometimes, each other.
- I am sure that some of the Mallard logged as adults, especially ducks, are in reality now full-grown ducklings of this year. Only the latest brood of three small ducklings identified as such.
- The Grey Heron flew from inside the island where it had been unseen.
- Only the Great Crested Grebe sitting on the nest was located.

Birds noted flying over / near The Flash:
- 1 Jackdaw

Hirundines etc. noted.
None

Warblers noted (singing birds):
- 3 (3) Chiffchaffs again
- 3 (3) Blackcap

Counts from the water:
- 3 + 4 Mute Swans again
- 27 Greylag Geese
- 1 Greylag x Canada Goose
- 136 Canada Geese
- 36 (20♂) + 3 (1 brood) Mallard
- 5 (3♂) Tufted Ducks
- 1 Grey Heron
- 1 Great Crested Grebe
- 1 Moorhen
- 21 + 10 (4 broods) Coots

(Ed Wilson)

------------------------------------------------------------------------------------------------------

Between the lake and The Flash:

- Single adult Moorhens seen alongside both pools: another adult calling at the upper pool
- 1 (1) Goldcrest at the lower pool
- 1 (1) Chiffchaff between the pools
- 1 (1) Blackcap at the lower pool

(Ed Wilson)

------------------------------------------------------------------------------------------------------

Trench Lock Pool:  06:50 – 07:00 // 07:50 – 08:25

(31st visit of the year)

Notes from here
- The Canada Goose goslings are clearly too young to fly and also too old to have been born since my last visit. So where were they last week? Not sure whether one of the goslings is just weaker than the others or whether it is the only survivor from a later brood.
- The single adult Great Crested Grebe was taking no notice of the surviving juvenile which was intermittently begging to no-one in particular.
- First returning adult Black-headed Gulls. They will now be here in variable numbers until March 2020!
- The adult Lesser Black-backed Gull usurped one of the Black-headed Gulls from its buoy and then minutes later flew off to land, rather unusually, on the roof of a house to the N.
- A third-summer Herring Gull stopped literally momentarily and then, like the Lesser Black-backed Gull, it flew to a roof to the N.
- Swifts and especially House Martins remain in low numbers. Local breeding in the estates seems very much reduced these days.
- No sound or sight of last week’s Reed Warbler.
- A Grey Wagtail here again.

Birds noted flying over / near here [other than local Wood Pigeons and Jackdaws]:
- 2 Rooks: species #54 for my 2019 bird list at Trench Lock.
- 1 Starling

Hirundines etc. noted:
- 2 Swifts
- 1 House Martin

Warblers noted.
None

Counts from the water:
- 2 + 4 Mute Swans
- 5 + 7 (2 broods?) Canada Geese
- 13 (11♂) Mallard
- [no Feral Mallard]
- 1 Grey Heron
- 1 + 1 (1 brood) Great Crested Grebes
- 1 Moorhen
- 19 + 5 (3 broods) Coots
- 2 Black-headed Gulls
- 1 Lesser Black-backed Gull
- 1 Herring Gull

An adult Lesser Black-backed Gull showing the effect of significant wing-moult with a big ‘step’ in the trailing edge where inner primaries and / or outer secondaries have been dropped and are regrowing.

A Herring Gull. Like most individuals I seem to see it is a bit of a puzzle. The mantle looked rather dark suggesting perhaps the Scandinavian race of Herring Gull or perhaps even a Yellow-legged Gull. This photo captures the wing-tip pattern perfectly and the amount and positioning of the black is more or less spot-on for a regular West European Herring Gull. So why did it look so dark mantled? Answers on a post card to ..... As an aside note that this bird too has shed at least one inner primary – most obvious as we look at the underside of the left wing.

(Ed Wilson)

------------------------------------------------------------------------------------------------------

Trench Middle Pool:  07:05 – 07:45

(31st visit of the year)

Other notes from here:
- I suspect that most of the geese are here to moult. Several seen wing-flapping and showing almost no flight feathers. No obvious sign of all the discarded feathers though.
- In amongst the Greylag Geese – most of the geese were in separate species groups – was an all-white bird with the same orange bill as the normal Greylags.
- The drake Tufted Duck flew off just after I first spotted it. Possibly it had only just dropped in.
- Only one adult Great Crested Grebe seen: plenty of places for the other adult to hide.
- Finding all the Moorhens and Coots amongst all the geese was not easy!
- A Grey Wagtail here also.
and
- two Mottled Beauty moths (Alcis repandata) on lamp poles
- one Garden Grass-veneer ‘grass moth’ (Chrysoteuchia culmella) on a lamp pole

Birds noted flying over / near here.
None

Hirundines etc. noted.
None

Warblers noted (singing birds):
- 1 (1) Chiffchaff
- 1 (0) Blackcap

Counts from the water:
- 2 Mute Swans again
- 128 + 13 (4? broods) Greylag Geese
- 1 all-white ‘Greylag’-type goose
- 108 + 14 (? broods) Canada Geese
- 10 (9♂) Mallard
- 1 (1♂) Tufted Duck
- 1 + 1 (1 brood) Great Crested Grebes
- 5 + 2 (2 broods) Moorhens
- 19 + 19 (>7 broods) Coots

Here is the all-white Greylag-type goose. From the photo and without any scale from surrounding birds it looks rather more like a duck than a goose. In context it was Greylag-sized.

This is one of the many ‘grass moths’ that abound throughout the summer and are a challenge to identify unless well seen. The marks look clear-enough: however the insect is angled towards us – I could not get around the other side – and we cannot see the rear of the wing which would allow 100% certainty of the identification. I am reasonably confident that it is a Garden Grass-veneer (Chrysoteuchia culmella) – by far the most common species flying at this date.

This moth is one of the ‘beauties’ which are also a challenge to separate. I am 95% certain this is a Mottled Beauty (Alcis repandata).

This is a different specimen. The diagnostic shape and strength of the outer cross-line is more distinct here and this IS a Mottled Beauty (Alcis repandata). Both these moth species are new for me at this site.

(Ed Wilson)

------------------------------------------------------------------------------------------------------

On this day..........

2016
Priorslee Flash
Today's News Here

2011
Priorslee Lake
Common Sandpiper - First returning
(Ed Wilson)

2008
Priorslee Lake
Common Sandpiper - First returning
(Ed Wilson)

2006
Priorslee Lake
1 drake Ruddy Duck
1 Snipe
1 Common Sandpiper - First returning
At least 38 Swifts
(Ed Wilson)