As those of you that follow me on twitter may already know, my second love to birds are the lepidoptera; butterflies and moths. This year I have decided to jump into ‘moth trapping’ with both feet, making my records available to the Garden Moth Scheme research group for the first time and so, as a result, I have decided that I might as well share my experiences with you and chronicle my garden moth recording on the blog throughout the year.
Moths often get a very bad rep; beige, dull, boring. There are a staggering 2500 species of moth on the British isles, 800+ of which are Macro moths (large moths) whilst the remainder are Micro moths (small moths). Of these you can expect to find a variety of several hundred in your garden, many more if there is suitable habitat. Amongst the greater population of moths many are just as, if not more spectacularly coloured than butterflies. Red, Green, Yellow, Orange and even Blue. The full spectrum is represented! Moths, of course, play a huge role in any healthy ecosystem with caterpillars providing food for small mammals, birds, amphibians and reptiles throughout their range as well as adult moths being extremely important pollinators. A decline in moths could spell disaster in the natural world, an incline could prove to be extremely valuable and yet moths, for all of their importance in the natural world, are widely under-recorded.
To get trapping, I have built my own ‘Robinson’ type trap (to buy a Robinson trap would be upward of £300) from some basic materials. The key to ‘light trapping’ is the type of light used; it is widely believed that moths use moonlight for navigation and the idea of ‘light’ trapping is to replicate that moonlight and draw in the moths. Although moths are drawn to light (you have probably noticed them banging off the kitchen window on a summers night!) they are most drawn to light in the UV spectrum and to replicate this in a trap, a special type of bulb emitting UV light is required. In my case I have used an actinic bulb; they are quite costly and difficult to get hold of but they are effective, economical and can be used with more basic electronic equipment. Another common bulb used in traps is the Mercury Vapour bulb and these are the most effective and most widely used in professional trapping, however they are extremely bright and when trapping in an urban or suburban garden, it might not go down too well with the neighbours! Mercury Vapour and Actinic bulbs usually require special electronics to operate and should never be plugged into the mains without the right equipment – luckily I have managed to source some compact fluorescent actinic bulbs with standard ES fittings so have managed to negate this often common problem. Moth traps are very simple and effective is design; moths fly towards the light, are funnelled into the main vessel where they hunker down in egg trays (mine kindly donated in bulk by a friendly local butcher). They can then either be studied and released later on that night, or the trap left to run in the morning where they can be observed in daylight and recorded. The moths are then usually released into a safe place in the morning or evening (in vegetation, or hedging – away from birds!) unharmed. On some heady summer nights it would not be uncommon for a Robinson trap to catch hundreds (I’ve even read of thousands!) of moths in a single night, so the identification and recording process can be rather time consuming, especially for the beginner.
Different moths are on the wing at varying times of the year, with a great bulk of them taking to our skies between May and September but there are still many species on the wing in every month of the year with some Autumn, Winter and March/April specialists. Many Lepidopterists trap all year round, though my journey is starting now, in March. Moths are far hardier in many cases than butterflies and can tolerate very low temperatures and often fly in rain; the best conditions for moth trapping are on mild, gust-free and overcast nights; clear skies often prove fruitless as when the moon is visible moths pay far less attention to artificial light and, navigating by the moon, become far less disorientated in their flight.
Common moths at this time of year are the Quaker, the Two Spot Quaker, Dotted Border, Hebrew Character, Early, Early Grey, Oak Beauty, Brindled Beauty, Satellite and Clouded Drab amongst others but the first visitor to my trap, in timely fashion was the aptly named ‘March’ moth (photographed above). OK, so the March moth does appear on first glance to be a little stereotypically beige and boring but it is quite an interesting species for a number of reasons. The male, as shown, has an unusual and distinctive resting position of overlapping wings, a rare trait, whilst the female is one of few species of moths that are apterous; wingless. This does solve the often difficult question of sexing, as it is only the winged males that are drawn to trap lights. The females can be found roosting bug-like on tree trunks, most notably Hawthorns, Oaks and Fruit-trees which are the larval food plant.
I hope, as the weeks go on and the weather warms up, that I will be able to introduce you to some of the more flamboyant moths of our isles. One of the exciting things about trapping is that you never know what you are going to get and somewhere along the way there is bound to be a surprise or two.