The Cult of Moth Trapping

What kind of crazy folk go out at night and gather round bright lights in the expectation of winged visitors? Stoned party-goers after a particularly heavy session? Die-hard pagan worshippers perhaps? And moth trappers obviously.

It was my delight both to participate in and bear witness to this strange spectacle on an evening with the Surrey Wildlife Trust and assembled experts on Chatley Heath in Surrey last month. It began innocuously enough with a barbecue meal and mildly alcoholic beverage, but then the great orb in the sky descended, the darkness gathered, and things began to get weird.

Moth trappers at Chatley Tower

Moth trappers at Chatley Tower

A white sheet stapled to the side of Chatley Semaphore Tower and illuminated with fluorescent light set the stage for our distinguished guests to arrive, and it wasn’t long before the lure of this burning beacon drew them in.

Moth trap and man with net

Moth trapper with net

At which point all pretence of ceremony evaporated and a man with net in hand, a wild gleam in his eye, pounced with the irresistible speed of a coiled spring released!

Once netted, the moth in question was transferred to an improvised lab bench nearby for inspection, ID and recording.

Identifying and recording moths

Identifying and recording moths

Steadily a queue of nocturnal visitors grew, each enclosed in a cylindrical plastic cell, and each requiring identification. A few of the larger, more striking moths, were familiar to the interested observer, but – to all except the most dedicated experts present – the majority remained strange and new.

Moth trap jars

Moth trap jars with inmates, including the yellow brimstone moth

There are roughly 800 species of ‘macro moth’ in the UK. These are the species you will find illustrated in standard field guides on the subject. But there have been 2,400 species of moth recorded in the UK when ‘micro moths’ are accounted for, and only the high priests of this cult can read the runes of their colouring and patternation with any degree of certainty.

On this particular night 73 separate species of moth were recorded – the list of outlandish guests including:

  • Water Veneer
  • Mother of Pearl
  • Maiden’s Blush
  • The Mocha
  • Lime-speck Pug
  • Coxcomb Prominent
  • Dark Sword Grass
  • Shuttle-shaped Dart
  • True Lovers’ Knot
  • Setaceous Hebrew Character
  • Neglected Rustic

Elsewhere on the heath nearby an even brighter beacon was being kindled: a Skinner Trap, fitted with a blinding electric bulb powered by its own noisy generator.

Skinner moth trap and trappers

Skinner moth trap and trappers

Not only is this contraption very effective at attracting moths, it’s also remarkably photogenic! A portal to another world appears to have opened up on the heath at night. And for all those present at this special event, it undoubtedly had.

Light rays from moth trap on heath

Light rays illuminate the heath

Nobody knows precisely why these creatures of the night are attracted to bright lights amidst the darkness, but it’s fortunate for us that they are.

With thanks to SWT Ranger Gemma.

Surrey Glow Worm Quest

If you’re looking for a photographic challenge then wildlife macro at night is guaranteed to keep you amused and frustrated in equal measure.

Glow worms (Lampyris noctiluca) come equipped with their own bioluminescent light source, and with a bit of research shouldn’t be too difficult to locate in the right environment. But in the dark simple tasks become considerably more complicated.

These ‘worms’ are in fact a beetle. On summer nights the flightless female glow worm climbs a grass stem,, or other vegetation, and emits a bright chemical light from her lower abdomen. This luminous display attracts the flighted male glow worm and mating begins, at which point the happy couple turn out the light and retire to bed together in the undergrowth.

In the UK glow worm numbers – or at least the number of people reporting them – have diminished over the years. Light pollution from sprawling urban areas may be one reason for this, as the female doesn’t like competition, and seeks out the darkest rural recesses in which to display to potential mates. The inexorable rise of the motorcar has also meant fewer people traversing the countyside on foot at night, and so less likelihood of happening across these creatures. Modern use of pesticides may also have played a part.

The wilds of South Dorset proved good hunting grounds for me last year and I was keen to have another crack at this subject in Surrey over the summer.

Sleeping Beauty

Sleeping Beauty: Dorset glow worm (Lampyris noctiluca)

Initial research turned up not much however. Almost every contact I quizzed looked at me with bafflement and a little wonder when I enquired about glow worms in the county, as if they’d become semi-mythical beasts in this stretch of the London commuter belt. A bit of Googling turned up a handful of vague mentions and precious few images.

The excellent UK Glow Worm Survey website, run by the extremely dedicated Mr Robin Scagell, offered more precise records and this especially tantalising glimpse of days gone by:

Box Hill, nr. Burford Bridge, Whole slope of Hill covered with glow-worms, summer 1915

Promising, but a long shot more than 90 years later perhaps. Then a chance meeting with a twitcher confirmed glow worms sighted in a very specific area of the hillside in the 1980s and the balance of probabilities swung in favour of action!

From my vantage point atop the steep chalk slope of Box Hill the sun began to set impressively, and the exhausting vertical scramble required to get there faded into memory.

Tight security in preparation for the Olympic cycle race meant that the entire National Trust property was ringed with high steel barriers. A checkpoint restricted traffic up the narrow zig-zagging road to the top, and guards with walkie-talkies patrolled its length. The pedestrian gates thankfully remained open.

Dorking at night

Town of Dorking in Surrey from Box Hill after dark

Bright lights from the dual-carriageway below continued to illuminate the entire downland slope after the sun had faded, which wasn’t promising. But in a deep, shady dip behind the ridge a twinkling greenish light in the grasses finally caught my eye.

In total 8 glowing females were located along a short stretch of chalk track.

The first young lady was tucked well back into the shrubbery and inaccessible to my lens. The second was more exposed, on leaf litter near to the ground. With a bit of tripod gymnastics and some macro slider extension action I edged within range.

Glow Worm Filigree

Glow Worm Filigree: Surrey glow worm on leaf litter

In this shot the natural glow from the beetle was supplemented with indirect light from an LED torch off to one side. It’s a balancing act to expose the whole subject without drowning out the insect’s own subtle illumination.

The same creature on a long exposure without the artifical light source gives a quite different visual impression:

Glow Worm Limelight

Glow Worm Limelight: Glow worm (natural light)

More typically glow worms can be found in thick grass, clinging to the stems a short way up, and rotating their bottoms skyward as this next one was:

Glow Worm Jade

Glow Worm Jade: Glow worm in grass

Where the beetle is tightly surrounded by reflective surfaces the light she emits is magnified.

In all the above images the glow worm’s head is firmly concealed beneath her carapace, and this is usually the case I’ve found. But before I departed for the night another individual proved less coy.

Glow Worm Red Light

Glow Worm Red Light: Glow worm under red filter LED

In these circumstances a bright white light can disturb the beetle, which then turns tail and vanishes, which is no good for observing behaviour. So I used a red filter, hoping she would be less sensitive to light in this part of the spectrum. It appeared to work and she continued to clean her antennae for some while:

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Oak Denizens After Dark

The English oak (Quercus robur) provides wonderful habitat for numerous creatures, but in the (relatively mild) depths of a British winter, they keep a low profile. Wait an hour or so after dark however and the trunk of an unassuming oak tree suddenly becomes an insect super-highway.

Oak bush-cricket, harvestman and winter moths montage

Oak bush-cricket, harvestman and winter moths montage

A particularly interesting creature is the flightless female winter moth, which emerges from the ground and climbs the nearest trunk to liaise with the flighted male moth at altitude. She then lays her eggs high up in the canopy.

Female winter moth

Female winter moth climbing oak tree

Male winter moth

Male winter moth lying in wait

In a ‘good’ year hundreds of female winter moths may be seen to climb the trunk of one tree in a single night. This is not necessarily good news for the tree however, as the caterpillars rapidly denude the leaves after emerging in the spring.

Taking photos of small wild creatures in the dark presents a few challenges!  To light these subjects I used an LED lamp attached to my tripod. This is a lot more predictable than using flash in inhospitable outdoor conditions, but does require a relatively long exposure time.

Many of these bugs will freeze in the bright white light required for conventional photography. This is not necessarily a bad thing for macro work, but it can alter their behaviour in an undesirable way. A young leopard slug was quickly in defensive posture for example, and remained so:

Young leopard slug

Young leopard slug

It’s also cold, dark and more than a little spooky in the woods after dusk in December, so requires several thermal layers and a degree of commitment!