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As a complete contrast to the usual moth trapping paraphernalia of mercury vapour lamps and elaborate traps, there exists a group of moths that require a totally different and more subtle approach when recording them. These are the family of day-flying moths known as the clearwings, a group of insects famed for mimicking wasps and ichneumons, but in reality are quite harmless both to man and other insects. However, very rarely some species can be troublesome and cause problems due to the larvae feeding on the wood inside healthy trees, the most likely being those that rely on apple trees and currant bushes for their survival. In Britain, fifteen species of clearwing have been recorded and all are known to be elusive, even to experienced naturalists whose best chance of locating them until the past few years was to find the freshly-emerged insect resting on their plant host, or at flowers such as privet or bramble. However, in recent times a completely new method of recording clearwings has been developed which has shown that many species are more widespread and frequent than previously thought. The invention of synthetic pheromone lures has revolutionised the study of these fascinating creatures, and it has given moth recorders a fresh outlook to one aspect of their hobby. These pheromones are now available commercially, with a variety of lures that are specific to the various species. The chemical attractant is impregnated in small rubber bungs or plastic tubes, each moth species having a unique type of pheromone. Sometimes they can also be used in combination, but with the need to avoid cross contamination as this nullifies their effectiveness. Having purchased a selection of these lures in 2010, I eagerly awaited an opportunity to use them once summer arrived. My initial foray on 7th June took me to Hockley Woods where, in very hazy sun, I used the 'VES' lure to good effect in a three year old coppice plot where female Yellow-legged Clearwings lay their eggs on the stumps of oak trees. The lure was placed in a small open weave bag and suspended several feet above the ground, generally on a low branch or bush in the sunshine. Within a few moments a couple of the clearwings arrived at the bait, the male insects fooled into believing that a newly-emerged female was available for mating. Several more arrived over the next few minutes and by re-locating in different situations around the coppice I verified the presence of at least ten Yellow-legged Clearwings, thereby confirming a healthy population at this ancient woodland. Over the next month I found this clearwing at two other sites in south-east Essex, firstly on 30th June at a nature reserve within Hadleigh Great Wood where I had the pleasure of strolling through the rides accompanied by Heath Fritillaries, White Admirals and many other butterflies. Within an extensive previously coppiced area I once again used the pheromone to good effect, the lure attracting at least a dozen moths when positioned in several locations around the sun-bathed woodland. A further excursion to the Langdon Hills on 3rd July yielded two Yellow-legged Clearwings at Northlands Wood, an excellent timbered habitat on a south-facing hillside and which has an on-going management regime. Another species of clearwing can be found in suburban gardens and orchards as well as the wider countryside, and they can occasionally be chanced upon feeding on hedgerow flowers such as privet. This is the Red-belted Clearwing, and I also had success in discovering colonies of them using the 'MYO' lure. The first sightings were in my in-laws garden on the day of their Golden Wedding anniversary, and this also proved to be a memorable event for me as well! In suburban Rayleigh on the mid-morning of 25th June the preparations were in hand for a garden party the following day, but luckily for me my attention was distracted by a female Red-belted Clearwing reconnoitring the espalier apple trees along the garden edge. She was hovering to and fro, slowly and deliberately inspecting the larger branches and obviously searching for suitable sites to deposit her ova, this normally being on slightly damaged sections of the bark or exposed wood. Some careful detective work revealed an exuvia of the species protruding from a branch, this being the empty pupa case of the clearwing after the adult has emerged. Two days later in the same garden I had the good fortune to encounter a pair of these clearwings 'in-cop', the engrossed pair resting amongst the shady foliage of a plum tree. I also used the lure to bring in a male, which finally lay to rest any suspicions as to whether the moth was breeding in the neighbourhood. A few days later on 30th June I visited a relative's garden in Leigh-on-Sea where a gnarled old apple tree provided me with more success as two males appeared at the 'MYO' lure. Another garden, this time belonging to the Ranger at the Langdon Hills Country Park supplied a single moth in the early afternoon of 3rd July, this adding another species to the already considerable list of wildlife recorded in the vicinity. My final sightings of this insect in 2010 were at the Magnolia Nature Reserve at Hawkwell on 10th July where a number of large crab apple trees shelter a colony of Red-belted Clearwings. A total of four insects arrived at the lure, with three of these at one particularly sizable tree on the edge of some secondary woodland. One of the finest sites for Lepidoptera anywhere in Essex is certainly Thorndon Park just to the south of Brentwood, and within the confines of this Country Park numerous types of butterflies and moths can be discovered - this now includes at least one species of clearwing, and a very notable one at that. There are historical records of several of these moth species from the area, most intriguingly of those that feed within birch trees and stumps, and on 17th June I attempted to reveal if they might still be resident amongst the former forest Deer Park. Unfortunately the cool breeze and intermittent sun were not ideal conditions for observing clearwings in open woodland , but a short ramble down to a sheltered valley with plenty of sallow bushes allowed me an opportunity to unearth a new outpost for the Red-tipped Clearwing, the larvae of which feed beneath the bark of the sallow. I hung the 'FOR' lure at a number of potentially suitable positions, and at 15.00 hrs a single clearwing appeared and danced around the bait. This was a completely new moth for me, and a fortnight later on 30th June I returned to the site with my friend Don Down and located another three Red-tipped Clearwings, again in only partially sunny weather. During the coming summer I hope to confirm this moth from at least one other site in south Essex as there are definitely similar environs locally where the insect could be breeding. A search for the Currant Clearwing at allotments in Leigh-on-Sea proved unsuccessful on 10th July despite ideal climatic conditions and plenty of mature red and black currant bushes around this well-established site. The insect is known from the area, and fortunately later the same day I used the 'TIP' pheromone to find a singleton at another allotment a mile or so away at Eastwood, where an overgrown currant bush no doubt harbours a colony of these clearwings. However, by far the most fruitful of the baits proved to be the 'API' lure for the Six-belted Clearwing, the larvae of which feed on the roots of birds-foot trefoil in Essex, usually in old grassland and disused quarries. I knew the species existed on Canvey Island, but I found this clearwing to be thriving at some alternative locations in south-east Essex, a corner of Britain that has never normally been one of the premier places to observe some of our rarer Lepidoptera! I first met the species on 27th June in the meadows of Willow Park, part of the Langdon Reserve managed by the Essex Wildlife Trust and situated on the high ground just south of Basildon. Here the lure was used to good effect as single insects arrived in two of the meadows, and although both are rich in the larval food plant it was rather surprising that so few clearwings came in to the pheromone. This was also the case on the 18th July where the lure failed to attract any of the moths despite warm sunshine and the very widespread and luxurious growth of the trefoil in all the situations where the bait was utilised. Things certainly improved with a visit on 3rd July to the nearby Country Park on the Langdon Hills - this easily exceeded my expectations and furnished excellent quantities of the insects in the middle of the afternoon. At least ten Six-belted Clearwings homed in to the lure at one meadow next to Martinhole Wood, and shortly afterwards on the hillside below One Tree Hill some twenty or so moths crowded around the pheromone suspended above the herb-rich sward. This incredible sight resembled a swarm of hoverflies and proved beyond question that the creature is well established here. Another half dozen of the moths were noted at the far corner of the field some distance from the first experiment, all in environs where the general public are enjoying the scenery of these open spaces - but who would ever know these unobtrusive insects existed here if it were not for the invention of the chemical lures? A return trip here on the 18th July found the moths continuing to prosper as again over twenty buzzed around the lure close to the Ranger's house, and a similar number appeared in the main meadow adjacent to Martinhole Wood. More surprising were the eight or so clearwings that drifted in from the scant vegetation of a heavily grazed pasture where Highland cattle have eaten nearly all the trefoil and left a rather uninviting scene for much wildlife. The fact that the larvae of this clearwing live underground have probably helped it to survive in what would otherwise appear unfavourable surroundings. A further sojourn to the Langdon Hills was made on the 15th August when up to fifteen Six-belted Clearwings made their presence known at One Tree Hill, and this in what is usually thought of as unsuitable climatic conditions for recording clearwings. The deterrent of a strong and cooling north-westerly breeze and only a very hazy sun peeping through a heavily overcast sky should have put off all but the most hardy of insects of any kind, but a reasonably sheltered aspect at the foot of the slope encouraged these moths to venture forth in high expectation, only to have their hopes dashed once again! I tried one last trip to this same location on 1st September, an extremely late date to see any of the clearwing family in this country. Despite this, and due in no small part to the perfect weather, I managed to attract two rather worn and faded Six-belted Clearwings to the lure, this possibly being one the latest ever records of these moths still being active in the wild. Prior to this I noted this clearwing species at two other sites in south Essex, firstly at Hawkwell where the Magnolia Nature Reserve played host to ten or so of the moths as they appeared out of nowhere and hovered back and forth in frenzied delight around the pheromone, only to realise their error and disperse back into the trefoils and clovers that carpeted the meadow at the heart of the reserve. Two visits were made to Grays Chalk Quarry, a long disused pit that is now well known for its localised plants and insects. The warden had no records for any of this family of moths, so he was excited to learn of my discovery of the Six-belted Clearwing from various corners of the site, some from near the top path around the rim of the quarry, and others down on the floor of the reserve where management is helping to preserve the important chalk grassland flora. My visit on 21st July in rather unsettled weather allowed me to find six moths in a brief sunny interlude from a cleared section high above the main pit, but a couple more were tempted to the pheromone at the base of the quarry whilst it remained overcast and just after a shower of rain. This was hardly expected as the clearwings are only supposed to be active in the sunshine, so this most likely proves the specific lure for the Six-belted Clearwing is especially powerful and can drag the insects away from their hideouts amongst the vegetation. A further venture here on 18th August brought another two clearwings from a part of the reserve not previously explored, on a path at the north of the site where it overlooks an oil storage depot, but still with an abundance of birds-foot trefoil all around. Unfortunately, during the course of 2010 I failed to find any Hornet moths, the largest of this group of moths in Britain. This may partly have been due to the removal of a couple of pollard black poplar trees close to my place of work in Westcliff-on-Sea where I had a few years earlier found several dozen exuviae of this imposing creature. There are fortunately similar mature trees nearby, one of which on 9th June 2009 left me astounded when at 14.00 hrs I found a total of five pristine Hornet moths on the trunk of a poplar tree in a park, consisting of two mating pairs and a female. They had remained in situ due to the cool and overcast conditions instead of flying into the canopy early in the morning as is generally the case. From a moderate number of excursions around the south of Essex I have been very fortunate to observe at close quarters many clearwings, not only as species but also with regard to the number of individual insects recorded. This is all from a variety of places and situations where they were formerly not suspected of occurring. The on-going use of pheromones should hopefully reveal more of their secret lives and hidden breeding grounds, some of which may well be right under our very noses! Summary of Clearwing species found in 2010 and numbers seen Six-belted Clearwing (Bembecia ichneumoniformis) - approx. 120 Yellow-legged Clearwing (Synanthedon vespiformis) - 24 Red-belted Clearwing (Synanthedon myopaeformis) - 12 Red-tipped Clearwing (Synanthedon formiciformis) - 4 Currant Clearwing (Synanthedon tipuliformis) - 1 - Graham Bailey (2010) montanabillgs@hotmail.com see also NBNR Moth Recording Project - Summer 2009 by Graham bailey |