Tag Archives: Robber Fly

Hot and Humid on Puttenham Common

Alder forest! The species likes to get its feet wet, growing by rivers and lakes. Here, a patch of damp low-lying land by the Tarn on the common gives a rare opportunity for a whole stand of the trees: surprisingly handsome, given their usual appearance as riverside bushes.
Black-tailed Skimmer resting near the Tarn. Several of them zoomed over the water, with an Emperor; a Great Crested Grebe fished; a fish jumped.
Large Skipper under the Birches
A Birch, unusually carpeted in crusty orange lichen (not Xanthoria, I think) or perhaps a non-lichen fungus
Handsome Polytrichum moss on forest floor
A Robber Fly with its prey, on Bracken

Drought, Baking Heat, Dragonflies … Thursley Common

Black Darters in wheeL The pools were very low from a month of drought, and many of the dragonflies correspondingly distant, but this pair came obligingly close.

Keeled Skimmer male sunbathing on boardwalk. Some definitely like it hot. Ask me about poikilothermy sometime, I’ll explain it to you.

Thursley Common boardwalk, bog, pools, pines, birch scrub, distant hills. A Hobby flew up, its back rather uniformly grey-brown. Seen soaring later from the side, its moustachial stripe was conspicuous.

Bordered Grey Moth, Selidosema brunnearia (a Geometrid)  in heather, its caterpillar’s favourite food

Beautiful Golden Y Moth, Autographa pulchrina (a Noctuid), hiding in heather

Robber fly on bell heather

Small Sand Wasp, Ammophila pubescens, continually in motion on a sandy path

Right at the end of the walk, a huge leaf-green Emperor Moth caterpillar (Saturnia pavonia), whorled with black tufts on each segment, walked briskly like a self-propelled cylindrical concertina across the boardwalk. Just as I grabbed my camera and leant up close, it fell down the gap between two planks and disappeared into the thick green grass below. It was a sight to behold, as long and thick as a finger.

Indian Summer on Thursley Common

A (very) Black Darter perched on a stone
A (very) Black Darter perched on a stone

A flock of some fifty Swallows twittered high above the sparkling blue lake among the bog pools. Dragonflies – the occasional Emperor, plenty of small red Common Darters and tiny Black Darters, some Migrant Hawkers – dashed about or sunned themselves on the boardwalks. A pair of Hobbies, those dashing, Swift-winged falcons, soared and watched the Swallows cunningly, waiting for a careless moment. One of the Hobbies swooped down, raced low, agile, among the reeds, up and switchback over a dead tree to snatch a dragonfly on the wing, powered right across the wide bog all the way to the pinewoods. Three pairs of Common Darters in cop, the males leading the females, their claspers about their females’ necks, flew in strict formation like so many Spitfires. A Hobby, high above the bog, accelerated in a long straight shallow dive, for all the world like a Junkers 88 bomber taking careful aim, racing down for a hundred yards at incredible speed to grab a dragonfly: it must have seen its prey all that distance away.

Birch Bog Bolete Leccinum rigidipes
Birch Bog Bolete Leccinum rigidipes

Clusters of the light brown Birch Bog Bolete – yes, it grows under Birches in Sphagnum bogs – are dotted about, their large squarish pores quite unlike the little round holes of the true Cep. Phillips says they’re edible but not worthwhile. This isn’t stopping a pair of plump thirty-something Poles with a sports bag wandering along collecting them (National Nature Reserve? Really?). I greet them, establish their nationality, say my mother used to do the same in the Carpathians and that there aren’t many mushrooms here. The guy with the sports bag shows me a meagre haul of Birch Bog Boletes just about lining the bottom of his bag: he means, he hasn’t found much worth collecting. I try Natsional Natur Reservat and waggle my finger, we part smiling and he shuffles off sheepishly.

Phaeolus schweinitzii (giant polypore)
Phaeolus schweinitzii (giant polypore)

Under some Pine trees, a dead stump, killed by Phaeolus schweinitzii, three or four enormous dinner-plate sized yellow discs, thick and rough with orangey-brown branching tufts: they are overgrown Polypore bracket fungi, dangerous parasites of conifer tree roots. Nobody has given it an English name, which is a pity as the namers could really have fun with it: Yellow Pine Death? Giant Pine Polypore? A magnificent fungus, somewhat alarming if you’re a forester.

On the open sandy heath, some Ammophila sandwasps are still active, perching on the path. A few butterflies – a white, some Speckled Woods, probably a Red Admiral – are about; a very large brown butterfly with agile flight, dancing around a pine trunk and up high, is tantalisingly impossible to get binoculars on, was very probably a Fritillary, in which case it was likely the Silver-Washed Fritillary.

Robber Fly Dysmachus trigonus on Thursley map
Robber Fly Machimus atricapillus on Thursley map

A couple of mean Robber Flies perched on a rather bleached map of the common: they had as Shakespeare said “a lean and hungry look”. They have a tuft of stiff bristles below their antennae to keep their prey from striking them in the head. They wait on a perch – a signboard will do if there’s nothing better – until an unsuspecting fly comes past, then they sally into the air and grab it.

Summer’s End Wildlife at Gunnersbury Triangle

Buff-tip moth caterpillar Phalera bucephala, top
Buff-tip moth caterpillar Phalera bucephala, top (22 September)

Buff-tip caterpillar, side view: fully 70 mm long
Buff-tip caterpillar, side view: fully 70 mm long

White Ermine caterpillar Spilosoma lubricipeda
White Ermine caterpillar Spilosoma lubricipeda found in the anthill meadow

Handsome Ichneumon, similar to but not I. stramentarius
Handsome Ichneumon, similar to but not I. stramentarius, which lacks the yellow crescent marking on the thorax.

 Plump Frog
Plump Common Frog

A big Funnel fungus Clitocybe
A big Funnel fungus, perhaps Frosty Funnel, Clitocybe phyllophila

Oak Gall, seemingly Marble Gall, though cracked
Oak Gall, seemingly Marble Gall, though cracked

Mining bee Lasioglossum on Ragwort
Mining bee Lasioglossum on Ragwort

Robber fly Dysmachus trigonus (Asilidae)
Robber fly Machimus atricapillus (Asilidae)

Yellow Iris fruit (nibbled seed pod)

Common Darter
Common Darter

Mangrove Swamp, wet
The “Mangrove Swamp”, wet and pretty. No air-breathing roots, though.