23 May 22

Priorslee Lake and The Flash

11.0°C > 15.0°C: Broken cloud at multiple medium / high levels. Tended to melt away with a few sunny spells after 08:45 before this set off development of puffy clouds. Light SSW wind. Excellent visibility.

Sunrise: 05:02 BST

Priorslee Lake: 04:40 – 05:50 // 06:45 – 09:35

(119th visit of the year)

Bird notes:
- At this time of year separation of overflying Herring Gulls from Lesser Black-backed Gulls becomes more difficult as they start to moult and become rather scruffy. In particular when birds pass more or less directly overhead my usual way of separating the species by noting the more translucent inner primary feathers of Herring Gulls falls down as these feathers are lost and regrown.
- Several groups of calling Blackcaps suggests fledged young were around. I did not see any.
- Now a fourth Garden Warbler sort of singing. Two birds are very intermittently singing where I heard the very first arrivals and at one of these locations I saw a non-singing bird yesterday. This implies these locations may have active nests. Two other birds continue to sing more or less constantly and I wonder whether they have yet to find a mate. It is a bit of a bind flying all the way back from Africa to fail to meet you soul-mate. The fifth bird this morning was one calling in yet another location.

Birds noted flying over here:
- 4 Canada Geese: pair outbound; quartet inbound
- 1 Greylag Goose: outbound
- 1 Feral Pigeon again
- 1 Stock Dove
- 12 Wood Pigeons
- 1 Collared Dove
- 3 Herring Gulls
- 10 Lesser Black-backed Gulls
- 1 Common Buzzard
- 5 Jackdaws
- 1 Rook

Hirundines etc. noted:
- 16 Swifts
- no Barn Swallows
- 6 House Martins

Warblers noted (figures in brackets relate to singing birds):
- 1 (1) Cetti's Warbler
- 12 (10) Chiffchaffs again
- 2 (1) Sedge Warblers again
- 9 (8) Reed Warblers
- 21 (14) Blackcaps
- 5 (4) Garden Warblers

Counts from the lake area:
- 4 + 2 (1 brood) Canada Geese: a pair arrived and soon departed
- 2 + 8 (1 brood) Mute Swans
- 3 (2♂) Mallard
- 3 Moorhens
- 19 + 3 (2 broods) Coots only
- 3 Great Crested Grebes again
- 2 Lesser Black-backed Gulls: adults, together and only briefly

Noted on / around the street lamp poles pre-dawn:
- 1 Tetragnatha sp. stretch spider yet again

Noted later:

Butterflies:
- *possible caterpillar of a Peacock (Aglais io)

Moths:
- *Plain Gold (Micropterix calthella)
- Common Nettle-tap (Anthophila fabriciana)
- *Silver-ground Carpet (Xanthorhoe montanata)

Bees, wasps, etc.
- Common Carder Bee (Bombus pascuorum)
- *Early Bumblebee (Bombus pratorum)
- Buff-tailed Bumblebee (Bombus terrestris)
- *Broad-striped Rhogogaster (Rhogogaster scalaris)

Hoverflies:
- Spring Epistrophe (Epistrophe elegans)
- Marmalade Hoverfly (Episyrphus balteatus)
- *Tiger Hoverfly (Helophilus pendulus)
- Chequered Hoverfly (Melanostoma scalare)
- *Superb Ant-hill Hoverfly (Xanthogramma pedissequum)
- *Orange-belted Leafwalker (Xylota segnis)

Damselflies:
- Common Blue Damselfly (Enallagma cyathigerum)
- Blue-tailed Damselfly (Ischnura elegans)
- *Azure Damselfly (Coenagrion puella)

Other flies:
- *Dagger fly Empis opaca
- Greenbottle Lucilia sp.
- *Grouse Wing caddis fly (Mystacides longicornis)
- Scorpion Fly (Panorpa sp.)
- Owl Midge Psychodidae sp.
- *Snipe Fly Rhagio scolopaceus
- Yellow Dung Fly (Scathophaga stercoraria)

Beetles etc.:
- *leaf beetle possibly Donacia vulgaris
- *Common Malachite Beetle (Malachius bipustulatus)
- 7 Spot Ladybird (Coccinella 7-punctata)
- *Harlequin Ladybird (Harmonia axyridis)
- *two other unidentified different species of beetle

Other insects:
- Common European Earwig (Forficula dentata)

Slugs / snails:
- White-lipped Snail (Cepaea hortensis)

Spiders:
- *Nursery Web Spider (Pisaura mirabilis)
- *Zebra Spider (Salticus scenicus)
- Tetragnatha sp. stretch spider

Mammals:
- Grey Squirrel

New flowers for the year:
- *Blue Flag Iris (Iris versicolor) / Blue Iris (Iris sp.)
- *Bittersweet (Solanum dulcamara)

Not an inspiring start. We did have some sun later for a while.

Not 100% sure about this 'do not eat me' caterpillar. It looks a good match for a Peacock butterfly (Aglais io) except for the yellow marks along the side.

One day I will get really crisp photos of Plain Gold moths (Micropterix calthella). Until then...

This moth flew away and tried to hide. It is a Silver-ground Carpet (Xanthorhoe montanata). A species that is easily and frequently flushed in daylight from any vegetation, often in gardens as well as the countryside. I expect I will get more opportunities to photo this species.

A puzzle. This looks to be one wing of a moth. There was no sign of anything else and I cannot identify it away from its natural folded position on a live insect.

Almost cuddly is a lovely furry Early Bumblebee (Bombus pratorum).

With a bit of persuasion I managed to get this sawfly to open its wings. The photo was good enough to enable me to use Stephen Falk's Flickr site to identify it as a Broad-striped Rhogogaster (Rhogogaster scalaris).

Here are two female Tiger Hoverflies (Helophilus pendulus). In the Helophilus group this the most orange-looking species. Females tend to show only two pale lines down the thorax. On the brighter-toned males the lines at each side of the thorax are more apparent and make it look like four lines.

The smartest hoverfly flying at the moment is this Superb Ant-hill Hoverfly (Xanthogramma pedissequum).

The swollen hind femur on this hoverfly suggests it is one of the Xylota group. The wings are hiding the abdomen markings but comparing the dark and pale areas on the legs with pictures on the web this has to be an Orange-belted Leafwalker (X. segnis).

There were hundreds of damselflies around this morning, many newly emerged and still to acquire adult colouration. This is an Azure Damselfly (Coenagrion puella) and I have enlarged the photo to show the club-like mark on segment two which most easily distinguishes this species from the Common Blue Damselfly (Enallagma cyathigerum) which has a 'U-shaped' mark (segment one is very small).

This is the Dagger fly Empis opaca. These attack and kill other flies often bigger than themselves. They have sharp piercing mouthparts.

Both the Grouse Wing caddis flies (Mystacides longicornis) I saw at The Flash were of the less common form with unmarked wings. This is a more typically-marked individual.

Another exciting-looking fly is this Snipe Fly Rhagio scolopaceus. Another predatory species with piercing mouthparts. Its no fun being a fly!

I think this may be the leaf beetle Donacia vulgaris. But then again...

An upgrade on my previous photos of Common Malachite Beetle (Malachius bipustulatus).

A Harlequin Ladybird (Harmonia axyridis) of the form spectabilis. I was bemused by the pink protrusion at the rear but cannot turn it in to anything else – note the 'white eyes' just about visible which rule out almost all other ladybird species.

Unknown beetle #1. There are pages of ostensibly similar-looking small black beetles in my literature. Where to start?

Unknown beetle #2. This appears similar to a number of soldier beetles though none of them has such pitted elytra.

This seems to be a characteristic daytime pose of Nursery Web Spiders (Pisaura mirabilis) with the legs all hunched up. The distinctive head shape shows. There were three of them close together.

Here is another. Like most species of spider the markings and colouration are very variable.

This tiny critter is a Zebra Spider (Salticus scenicus), one of the jumping spider species. It needs to take care where it jumps as it is six feet up a lamp pole here. No doubt it is tied on with to silk to prevent catastrophe though it weighs almost nothing.

Always flowering ten days or so after its cousin this plant is often recorded as Blue Flag Iris (Iris versicolor). It is non-native and all populations are derived from garden escapes, often commercial hybrids, and are perhaps best described as Blue Iris (Iris sp.).

My first flowers of Bittersweet (Solanum dulcamara) this year. Also known as Woody Nightshade. The foliage and berries are poisonous and can kill if eaten in large quantities. The family to which it belongs also includes tomatoes, potatoes and aubergines!

(Ed Wilson)

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The Flash: 05:55 – 06:40

(116th visit of the year)

Bird notes:
- If I have this right the brood of seven small same-sized Canada Geese goslings I saw was a new brood: they rapidly disappeared under overhanging vegetation. Which leaves the question of where the other goslings might have been. Perhaps (I hope) they had wandered off in to the estate and were in gardens somewhere.
- Only one juvenile Moorhen seen. This was now off the nest and inside the reeds and its sibling could well have been hiding away.
- Some more juvenile Coots seen: the recent single bird was with a sibling; the brood of four was only three-strong today but the fourth was likely in the reeds. A single newish juvenile was by the island; and two well-grown and previously unseen juveniles were along the E side.
- Just two Great Crested Grebes. This pair made a complete circuit of the water as if demonstrating that it was their patch.

Birds noted flying over here:
- 2 Canada Geese
- 1 Herring Gull
- 1 Lesser Black-backed Gull
- 2 Jackdaws

Hirundines etc. noted:
- 1(!) Swift

Warblers noted (figures in brackets relate to singing birds):
- 2 (2) Chiffchaffs only
- 3 (3) Blackcaps

Noted on / around the water:
- 48 + 7 (1 brood) Canada Geese
- 1 Greylag Goose
- 3 Mute Swans
- 21 (19♂) Mallard
- 1 (1♂) all-white duck (Aylesbury Duck)
- 6 (4♂) Tufted Duck
- 8 + 1 (1 brood) Moorhens
- 20 + 8 (4 broods) Coots
- 2 Great Crested Grebes
- 1 Lesser Black-backed Gull: adult; departed

Noted on / around the street lamp poles:
- *1 Common Marbled Carpet moth (Dysstroma truncata)
- *1 Pale Tussock moth (Calliteara pudibunda)
- 1 Tetragnatha sp. stretch spider

These two moths take my 2022 moth species count here to 11.

Noted elsewhere:
- 1 Grey Squirrel

A different form of a Common Marbled Carpet moth (Dysstroma truncata). I do not recall having seen one like this with an obvious red sub-terminal area.

Another moth species with furry legs. It is a Pale Tussock moth (Calliteara pudibunda).

From the side the 'tussock' is visible.

(Ed Wilson)

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Between the lake and The Flash:

- A pair of Mallard again sitting on the grass nearest the upper pool
- Moorhens heard calling at the both pools: it sounds as if they have juveniles but it is too overgrown to be see much of what is going on.
- 1 Chiffchaff singing beside the lower pool

(Ed Wilson)

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In the Priorslee Avenue tunnel:

- *1 Common Pug moth (Eupithecia vulgata)
- very few midges

Another of those pesky pug moths was on the roof. As far as I can tell this is a Common Pug (Eupithecia vulgata)

(Ed Wilson)

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

Sightings from previous years without links are below

2006

Priorslee Lake

Mink seen by locals

(Ed Wilson)