CHRISTMAS OFFER Subscribe to Dorset Magazine today CLICK HERE

Colourful moths and their role as artful dodgers in late summer

PUBLISHED: 10:24 08 September 2014 | UPDATED: 10:24 08 September 2014

Six-Spotted Burnet Moths

Six-Spotted Burnet Moths


The colourful moths we see in late summer have some cunning ploys to deter predators, from wing displays designed to dazzle and play optical tricks to oozing poison on their enemies, says Professor Philip Howse

Cinnabar MothCinnabar Moth

Moths have the art of a magician when it comes to camouflage. Think of a moth and you may have an image of a dull grey or brown triangular thing, looking like a dead leaf below the porch light. But not all are like that. Many are exquisite mimics of bark, lichens, broken twigs, dry grasses, dead leaves and fungi while others are as brilliantly coloured as any butterfly.


Cinnabar Moth

The colour red is a powerful signal for us but most animals (including bulls) do not see red. For them is just one of the hundred (not fifty) shades of grey. However insects and birds, which are the main predators of butterflies and moths do see it, and we can see it particularly clearly against a black background. It’s no surprise then that the Cinnabar Moth (Tyria jacobaeae) is so conspicuous when it takes wing in the sunlight, like an animated rose petal of the deepest red. Despite the name, the scarlet pigment is not cinnabar - a toxic mercuric ore used for decoration in ancient cultures. It is more likely to be cinnamic acid - a red colourant used widely today - derived from the aphid-like cochineal insect which was imported into Spain in the 15th century by the Conquistadors.

Although cochineal is harmless, the cinnabar is very poisonous - cyanide oozes from glands behind its head. Its caterpillar is no less lethal; it feeds on ragwort, the plant that kills cattle and horses if they graze on it. Its yellow and black wasp stripes advertise that it is full of toxic alkaloids, although the caterpillar is immune to them itself.


Tiger Moths

In his poem St Agnes Eve, Keats describes the bed-chamber of the demi-goddess Madeline with reference to vibrant images and colours, including those of a moth:

‘A casement high and triple-arch’d there was, All garlanded with carven imag’ries Of fruits, and flowers, and bunches of knot-grass, And diamonded with panes of quaint device Innumerable of stains and splendid dyes, As are the tiger-moth’s deep-damask’d wings.’

Unless you have seen a tiger moth, and probably many poetry lovers have not, the vivid allusion to lustrous red- and blue-dyed damask silk will be lost on you. But in the summer and you can see such brightly coloured moths. The Garden Tiger Moth (Arctia caja), for example has wings patterned like a brindled cow, breaking up its shape and outline. Disturb it and you have a shock and awe effect as it exposes its hind wings with iridescent blue spots on a red background. Advertisers avoid using blue print on a red background, and the converse, because blue and red focus at different levels on the retina and produce a strange dazzle effect. The moth’s display is designed to startle predators and to warn them that this creature may be poisonous.

Keats, however, was more likely to have had in mind the Scarlet Tiger Moth (Callimorpha dominula) which sometimes flies by day and has deep crimson hind-wings. The image above was taken with the moth on a window pane, and the back lighting reinforces colour of the brilliant silky hind-wings producing a deep numinous colour that surely was the poet’s inspiration.


Burnet Moths

On chalk and limestone downs in July and August you cannot fail to see iridescent Burnet Moths flying like black red-winged bees in the day time. The famous entomologist Dame Miriam Rothschild tested one for palatability and nearly died. She later found that it produces hydrocyanic acid - a deadly poison for any insect predator.


Burnished Brass Moth

The aptly named Burnished Brass Moth (Diachrysia chrysitis) has another clever strategy to avoid predators. Like the polished brass and purple vestments in a church, its delicate colours glisten in the light. Usually in the darkness of foliage it stays hidden but when disturbed it fans its wings producing a shimmering reflection that is likely to startle and confuse any predator, and give it an escape route. The iridescent colours are produced by internal reflections in the scales that line the wings in a similar manner to those produced by a soap bubble.


Magpie Moth

Nocturnal predators do not see colours, so camouflage colours are only needed for moths that hide from birds during the day. There are some brightly coloured moths, though, that fly in the daytime if they are disturbed. One of these is the Magpie Moth (Abraxas grossulariata) which has wasp banding on its body and bright wings which are, remarkably, embroidered with pictures of its caterpillar - a “looper” with the same orange and black blotchy patterns. The reason is simple: both the caterpillar and the moth are poisonous, so any bird that has tried eating this moth’s offspring will tend to avoid them when they become adult.


About Philip Howse

Professor Philip Howse taught animal behaviour and entomology at the Universities of Cardiff and Southampton. His research took him to countries including Brazil, Venezuela, Mexico, Nigeria, Malaysia, the West Indies and India. He invented methods of controlling insect pests of horticulture and agriculture without the use of synthetic pesticides, for which he received various awards including the OBE and a Prince of Wales Award for Innovation. His books include Butterflies, Messages from Psyche and (with Kirby Wolfe) Giant Silkmoths; Colour, Mimicry and Camouflage (both published by Papadakis). He is currently working on his next book The Vicar of the Amazon, The Reverend Miles Moss about a Victorian butterfly collector, artist and musician.


Read on

Searching for the Silver-spotted Skipper in Shaftesbury

Rosemary Free from the Bumblebee Conservation Trust on how you can help protect the species

*VIDEO* Stone Curlew spotted in Portland Bill


Welcome , please leave your message below.

Optional - JPG files only
Optional - MP3 files only
Optional - 3GP, AVI, MOV, MPG or WMV files

Please log in to leave a comment and share your views with other Dorset visitors.

We enable people to post comments with the aim of encouraging open debate.

Only people who register and sign up to our terms and conditions can post comments. These terms and conditions explain our house rules and legal guidelines.

Comments are not edited by Dorset staff prior to publication but may be automatically filtered.

If you have a complaint about a comment please contact us by clicking on the Report This Comment button next to the comment.

Not a member yet?

Register to create your own unique Dorset account for free.

Signing up is free, quick and easy and offers you the chance to add comments, personalise the site with local information picked just for you, and more.

Sign up now

More from Out & About

Friday, December 7, 2018

This easy walk takes us into Hardy territory as well offering some glorious views towards Weymouth and Portland

Read more
Thursday, November 29, 2018

Here are some Dorset walks, easy and challenging, to get you out and about over the festive period

Read more
Wednesday, November 28, 2018

If you’re willing to brave the cold this Christmas Day, check out Dorset’s festive swim calendar for the best organised dips taking place in 2018

Read more
Thursday, November 15, 2018

Confusion reigns on the county’s eastern border

Read more
Thursday, November 15, 2018

From festive light switch-ons and Santa’s Grottos, to German Christmas markets and late-night shopping, we’ve covered what’s on in Dorset this season

Read more
Monday, November 12, 2018

From your first step, you will see superb views from hilltops and farmland footpaths on this walk

Read more
Sunday, November 11, 2018

Martin Clunes and his family have called West Dorset home for over two decades. Here he shares some of their favourite local places

Read more
Monday, November 5, 2018

To mark the centenary of the end of World War One we visit some of the memorials erected across Dorset to remember the fallen in the ‘war to end all wars’

Read more
Friday, October 26, 2018

This lovely walk takes us from watercress beds to a church famous for its life-size carvings of apostles

Read more
Thursday, October 25, 2018

Autumn is a great time to brush up on your gardening knowledge with the help of some experts, as well as see some well known gardens in a different light

Read more
Wednesday, October 24, 2018

The guide to Dorset’s best firework displays and bonfire events happening in 2018

Read more
Tuesday, October 23, 2018

Prepare to experience the paranormal this Hallowe’en as Visit Dorset reveals some of the county’s most haunted pubs, stately homes, historic buildings and tanks

Read more
Monday, October 15, 2018

Dorset villages are some of the most beautiful in England – think winding lanes, thatched cottages and a cosy pub or welcoming tea room. We suggest ten of the prettiest villages to visit in the county

Read more
Friday, September 14, 2018

Follow in the footsteps of the Romans on this lovely walk that takes in rare habitat, ancient woodland and glorious views

Read more
A+ South & South West

Newsletter Sign Up

Sign up to the following newsletters:

Sign up to receive our regular email newsletter

Our Privacy Policy

Topics of Interest

Subscribe or buy a mag today

subscription ad

Local Business Directory

Property Search