10 May 23

Priorslee Lake only

8.0°C > 12.0°C:  Mainly sunny. Light westerly wind. Very good visibility.

Sunrise:  05:22 BST

* = a photo from today

Another abbreviated visit to the lake only.

Priorslee Balancing Lake:  05:10 – 07:55

(94th visit of the year)

Bird notes:
- The Canada and Greylag Goose families have each lost a gosling.
- A Collared Dove briefly perched on a street lamp pole in Castle Farm Way. I usually only see these around the Teece Drive / estate area.
- A Garden Warbler was singing by the Teece Drive gate as I arrived but was not seen or heard subsequently.
- 12 Starlings were feeding on the bank of the football field at 06:15. Many birds seem strangely reluctant to feed on the grass within the fenced area.

Birds noted flying over here:
- 9 Canada Geese: a single, a duo and two trios all outbound
- 16 Wood Pigeons
- 1 Lesser Black-backed Gull
- 1 Jackdaw
That's all!

Warblers noted (the number singing in brackets):
- 1 (1) Cetti's Warbler
- 2 (2) Willow Warblers
- 12 (11) Chiffchaffs
- 1 (1) Sedge Warbler again
- 11 (11) Reed Warblers
- 16 (13) Blackcaps
- 1 (1) Garden Warbler
- 2 (2) Common Whitethroats again

Hirundines etc., noted:
- 2 Swifts

Counts from the lake area:
- 5 + 5 (1 brood) Canada Geese: the resident pair with goslings; a pair arrived; a single visited briefly
- 2 + 9 (1 brood) Greylag Geese
- *2 + 3 (1 brood) Mute Swans
- 6 (5♂) Mallard
- *2 (1♂) Tufted Duck: briefly
- 4 Moorhens
- 27 Coots: no juveniles noted
- 3 Great Crested Grebes only

Noted on the street lamp poles pre-dawn:
- *1 green-bodied midge, perhaps Stenochironomus gibbus
- 1 slug
- 1 Clubiona sp. spider
Still no moths.

Noted later:
- *Orange-tip butterfly (Anthocharis cardamines)
- *Common Blue Damselfly (Enallagma cyathigerum)
- *Tiger Hoverfly (Helophilus pendulus)
- *Dead-head Hoverfly (Myathropa florea) [Batman Hoverfly]
- Alder Fly (Sialis lutaria)
- *Plumed Midge (Chironomus plumosus)
- *Dock Bug (Coreus marginatus)
- Alder Leaf Beetle (Agelastica alni)
- *presumed Raspberry Beetle (Byturus tomentosus)
- *another beetle sp.

On the ceiling and one wall of the Priorslee Avenue tunnel:
- 8 midges of c.3 species.

The last of the cloud moving away gave brief colour to the early dawn.

The Mute Swans seem to have just three cygnets this year. This is an unusually low number. Typically six to ten eggs are laid and whilst it is not unusual for one to be infertile and for a weak cygnet to be lost very soon after hatching then it remains a poor showing. Last year this pair hatched at least eight cygnets, four of which fledged (albeit one of these has recently been found dead).

The pair of Tufted Duck that briefly settled here, the duck leading the white-flanked drake.

And still leading him as they fly away.

My first Orange-tip butterfly (Anthocharis cardamines) of the year. Only the males have orange wing-tips.

Here from underneath. Females resemble other 'white' butterflies in flight though they have the same markings as the males on the underside of the hindwing. Not always easy to see, especially in flight.

Very recently emerged and still lacking any colour is this female Common Blue Damselfly (Enallagma cyathigerum). Just one day earlier than I recorded my first in 2022.

My first Tiger Hoverfly (Helophilus pendulus) of the year on a typical 'first date'.

The markings on the thorax give this hoverfly a vernacular name of Dead-head Hoverfly (Myathropa florea). It does not seen especially apposite to me. Steven Falk calls it Batman Hoverfly which strikes me as little better.

On a street lamp pole this morning I found this green midge. The NatureSpot web site shows a midge of this colour, Stenochironomus gibbus, but notes it has a darker band across the wings that this seems to lack. This could be because the camera flash has 'blown it out'.

With its banded abdomen this looks to be a female Plumed Midge (Chironomus plumosus). Only the males have plumed antennae (for detecting the females' pheromones).

A pair(?) of Dock Bugs (Coreus marginatus) cosying up.

The tiny beetles in this buttercup flower (Ranunculus sp.) are likely Raspberry Beetles (Byturus tomentosus). When I first noticed them I wondered whether they might be the tiny moths called Plain Gold (Micropterix calthella) that also like buttercups. Checking my records it could be another two weeks before these moths emerge.

I found several of these shiny blue-black beetles on the boxing ring on the dam. They are not Alder Leaf Beetles (Agelastica alni): beyond that I cannot say as there are many to choose from.

(Ed Wilson)

------------------------------------------------------------------------------------------------------
On this day can be found via the yearly links in the right-hand column.

Sightings from previous years without links are below

2013
Priorslee Lake
Great White Egret
(Ed Wilson)

2006
Priorslee Lake
2 Ruddy Ducks
(Ed Wilson)