Digger Wasp Hostage

Sand digger wasp with caterpillar

The sand digger wasp (Ammophila sabulosa) paralyses its prey

We encountered another variety of sand digger wasp on the heath recently – this time Ammophila sabulosa, which uses caterpillars to feed its larvae.

Sand digger wasp with caterpillar prey

Sand digger wasps’ prey may be 10 times heavier than the wasp itself

Similarly to the spider-hunting wasp (Anoplius viaticus) it paralyses its victim with venom from its sting and buries it in a nest burrow. The caterpillar remains paralysed until the wasp larvae hatch out and eat it alive!

Sand digger wasp excavating nest burrow

Female sand digger wasps excavate a short burrow in sand

The entire nest cycle from site location, through excavation and provisioning, to finally sealing the burrow, takes 8-10 hours to complete.

Many wasps have ingenious parasitic strategies, as these earlier blog posts illustrate:

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The Magnificent Puss Moth

Puss moth caterpillar

The puss moth caterpillar’s ‘eyes’ are only for display

A colleague working for Surrey Wildlife Trust kindly guided me to the location of this wonderful puss moth caterpillar (Cerura vinula) yesterday. A pair of them were contentedly grazing on aspen leaves.

Puss moth caterpillar grazing on aspen

Puss moth larvae feed on poplar, willow, or here on aspen

Colourful character

In adult form the furry grey and white moth flies at night between the months of May and July. The larval form looks much more exotic. The gawdy pink ring around its face gives the puss moth a very distinctive appearance.

Puss moth caterpillar

Head end of puss moth caterpillar

Self defence

If disturbed the puss moth caterpillar extends two whip-like appendages from its tail end and flails them around to deter attackers. It’s a bizarre and unexpected thing to witness.

Puss moth caterpillar tail

Puss moth caterpillar with extended ‘tails’

Puss moth caterpillar tail

‘Tail’ detail of puss moth larva

It also has the ability to squirt formic acid from its thorax if further provoked, but I didn’t try that!

Winter retreat

Shortly before pupation the caterpillar will change to a fetching shade of orange, and then again to purple.

It spins a cocoon of silk around itself and uses bits of tree bark as camouflage to stay hidden for the winter. The resulting cocoon is one of the strongest constructed by any UK moth.

I will have to return to see if I can find it in its various rainbow stages of development.

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Springwatched

Spider hunting wasp with spider

Spider hunting wasp with paralysed arachnid prey

The team at BBC’s ‘Springwatch Unsprung’ programme used a sequence of my photos to illustrate the intriguing behaviour of the spider-hunting wasp, Anoplius viaticus.

This solitary wasp targets spiders, which it paralyses with venom and then hauls back to its subterranean nest burrow. Once wrestled inside the female wasp will lay its eggs on the spider’s body for its larvae to eat when they hatch.

Bug expert Nick Baker explained that this species stores its prey before excavating the burrow and so the unattended spider often becomes the victim of a tug-of-war between Anoplius viaticus and other opportunistic wasps and ants.

BBC Springwatch studio broadcast

Chris, Nick, Michaela, Martin and the Springwatch gang

Natural history superstar Mr. Chris Packham then related the curious fact that one of his first ever TV assignments was to film this invertebrate behaviour on nearby Studland Beach – this being made all the more awkward because it’s also frequented by enthusiastic naturists! Happily this particular site was a safe distance to the north on the peninsula. 🙂

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Hornets

Hornet cleaning leg

Male hornet cleaning its front legs.

The hornet (Vespa crabro) is Britain’s largest wasp species.

They prey on other wasps, honey bees, flies, butterflies, moths and spiders.

Hornet predating solitary wasp

Hornet disassembles solitary wasp prey

Saplings are ring-barked to encourage sap flow, which is then collected.

Hornets drinking birch sap

Hornets drinking sap from stripped birch sapling.

Nests are usually in aerial situations, particularly inside hollow trees, but also in attics and outhouses.

Hornets returning to nest

Hornets entering and exiting nest in trunk of hollow pine tree (composite)

Hornets' nest

Abandoned hornets’ nest in outside toilet.

Despite their fearsome reputation hornets are actually remarkably docile creatures and I found them much less intimidating to photograph than their common wasp (“yellow jacket”) relatives.

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Buglife: Glow Worm Survey

Buglife are using my image in their postcard campaign to publicise a glow worm survey in Scotland this summer:

Glow worm postcard

Scottish Glow Worm Survey postcard

Glow worms are widely distributed in the UK, with records from the south of England up to the north of Scotland, but there have been very few Scottish records in recent years.

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Dorset Life: Hunters

A selection of my images illustrates an article about predatory animals and plants in the May edition of Dorset Life magazine, out this month.

Dorset Life magazine

Dorset Life: Dorset Hunters. Double spread I

Dorset Life magazine

Dorset Life: Dorset Hunters. Double spread II

Featured flora and fauna include: the kestrel, adder, red fox, otter, sundew, kingfisher and hornet robberfly. Words by Joël Lacey.

Available now at all good newsagents and supermarkets in the Dorset area!

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Adder Ecdysis

Complete adder skin

Complete sloughed skin of adder (Vipera berus)

Periodically snakes and other animals shed their entire skins, in a process known as ecdysis (or sloughing, or moulting).

Moulting takes up to 14 days to complete. The inner surface of the old skin liquefies, which causes it to separate from the new skin beneath it. By rubbing its skin on hard objects the end nearest the head begins to peel back on itself, until the snake is able to crawl out of its skin, turning it inside-out like a sock.

Head of adder skin

Head end of moulted adder skin

The ocular scale, or ‘brille’, is discarded along with the rest of the skin. This is essential for maintaining the snake’s quality of vision.

Ocular scale of adder

Adder skin showing ocular scale detail

The visually striking process of renewal exhibited by these animals is one reason why serpents have historically been symbolic of healing and medicine in our culture.

Adder skin

Adder skin with side illumination

Snake skin is formed from the remarkably adaptable substance keratin. Some of its properties are best appreciated in close-up:

Adder skin closeup

Backlit adder skin detail

Underside of adder skin

Underside of adder skin showing transparent keratin scales

This particular skin was found on heathland, woven in amongst some dried grasses. We later stumbled across a stunning, newly sloughed, caramel-coloured female sunning herself nearby.

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Butterfly Conservation Moth Report

Butterfly Conservation: Moth Report 2013

Butterfly Conservation: Moth Report 2013

Butterfly Conservation used my image of a nocturnal moth trapping event to illustrate their latest report:

Unsurprisingly the report concludes that UK moth numbers are in decline, documenting a 40% drop in total abundance in the south of England over the last 40 years.

On the bright side many more moth species have colonised Britain in recent decades than have become extinct.

This photograph was taken at a recent moth trapping event on Chatley Heath organised by Surrey Wildlife Trust. The original image below:

Moth Trap Assembly

Skinner Trap on Surrey heathland at night

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Suburban Oak

Suburban Oak

The ancient Crouch Oak in Addlestone, Surrey, UK

The Crouch Oak once marked the perimeter of Windsor Great Park and is thought to date from the 11th Century, making it in excess of 900 years old.

This ancient tree now looks a little incongruous as a modern residential estate has grown up around it.

Night Oak

The Crouch Oak at night with passing traffic

It’s interesting to compare depictions of this tree from the 19th Century and in 1904 as wooden fences are replaced with metal railings and a dusty track becomes a surfaced road. The oak also enjoyed an additional limb in those days.

In more recent times the Crouch Oak survived an arson attempt in 2007 and is now fitted with metal grilles across its hollow openings to prevent a repeat.

Oak Urban Effects I

Metal grille stops burning objects being thrown inside

To see the Crouch Oak for yourself follow the map below to the bend in Crouch Oak Lane:

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Dartford Warbler Winter

Dartford Warbler Snow Drift

Dartford warbler (Sylvia undata) foraging on snow covered heathland

In the severe winter of 1962/63 the Dartford warbler (Sylvia undata) was almost wiped out in Britain. The national population dropped to just 10 pairs.

But in good breeding seasons, and with suitable habitat, its numbers are capable of bouncing back, thanks to repeated nesting and high survival rates among its offspring.

On the Surrey lowland heaths Dartfords have been doing well, re-colonising Thursley Common last year for the first time since a devastating fire in 2006.

During the recent freezing winter weather I photographed this Dartford warbler foraging in the snow on Chobham Common:

Dartford Snow Flurry

Dartford Snow Dipper

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