Jono Forgham
Graeme J Smith, Steve Easby and Jono Forgham of Herts Moth Group set up three light traps within the wood around 8.30pm on the Friday night for a public moth night. Local residents were invited via the Birchanger Wood website and Facebook account, posters within the wood and a mention in the local newspaper.
In total, around 20 people turned up, including four children. Jono gave a brief introduction as to how the traps work and a little on the biology of moths, detailing their evolution and that there are two large groups of moths, split into micro moths and macro moths. The temperature was perfect for a late May night and by 9.15pm the group began wandering around the wood. The children were given pots and a net to see if they could catch any early fliers and the first moth to be taken was a Nemapogon cloacella, the Cork moth.
The traps consisted of 2 Robinson type traps with 125W mercury vapour bulb powered by inverter generators and a smaller Heath type trap running off a 12 Volt battery with a 15 watt actinic tube.
Mothing was slow as it appeared to be quite dark, but a look to the sky proved that it was still too light for most moths, especially the macros to be on the wing. This was a shame as it was getting too late for the children who had to leave around 10pm and it was shortly after this that moths became more apparent, roosting on the sheets that had been set adjacent to the traps.
By now, bats could be seen flying, especially around the open spaces of the water tower. Jono had brought his bat detector that amplifies the sounds bats make to guide their flight. By setting the device to a specific frequency the bat can be identified to species by the sound and also by the kilohertz range. These bats were within the range 45 – 52KhZ which showed they were Pipestrelle bats. A larger bat was seen flying within the wood but had disappeared before the detector could be set to the correct range.
By now the group settled around one of the larger traps and Graeme and Jono talked folk through the species. At this point the highlight of the night for most of group made an appearance, a large female Poplar hawkmoth. Other good moths seen included a Figure of 80 and a Brindle white spot, the latter being an uncommon moth for East Herts with only a few records for Bishop’s Stortford, being more common within Broxbourne Woods further south. A moth that uses oak, lime and birch as its larval foodplant.
It was then decided that the traps should be checked, so the group gathered around each trap in turn as the moths were checked roosting on the egg boxes placed inside the traps. They were all counted and listed.
In total, a somewhat disappointing 106 moths of just 32 species were recorded. We had anticipated twice as many but packing up by midnight meant we missed a good selection of the late flyers. Another trapping night towards the end of July will offer a much wider selection of high summer species in considerably larger numbers. However, all that attended seemed to have enjoyed the evening, seeing many moth species for the first time.
Our next event is the Bug Hunt on 22nd June, from 11am to 1pm – meet at the compound by the water tower, Heath Row, Bishop’s Stortford.
Birchanger Wood Moth Survey, 31 May 2019
| SPECIES | NUMBER OBSERVED |
| Micro | |
| 0125 Emmetia marginea | 2 |
| 0140 Nematopogon swammerdamella | 5 |
| 0148 Nemophora degeerella | 1 |
| 0216 Cork Moth (Nemapogon cloacella) | 30 |
| 0224 Triaxomera parasitella | 1 |
| 0343 Phyllonorycter esperella | 1 |
| 0417 Argyresthia spinosella | 1 |
| 0648 White-shouldered House Moth (Endrosis sarcitrella) | 3 |
| 0661 Pseudatemelia flavifrontella | 1 |
| 0921 Phtheochroa inopiana | 1 |
| 0986 Syndemis musculana | 1 |
| 1082 Plum Tortrix (Hedya pruniana) | 2 |
| 1174 Epiblema cynosbatella | 1 |
| 1176 Epiblema trimaculana | 1 |
| 1392 Udea olivalis | 1 |
| 1428 Bee Moth (Aphomia sociella) | 4 |
| Total Micros | 56 |
| Macros | |
| 0017 Common Swift (Hepialus lupulinus) | 20 |
| 1654 Figure of Eighty (Tethea ocularis) | 2 |
| 1727 Silver-ground Carpet (Xanthorhoe montanata) | 2 |
| 1728 Garden Carpet (Xanthorhoe fluctuata) | 1 |
| 1764 Common Marbled Carpet (Chloroclysta truncata) | 3 |
| 1776 Green Carpet (Colostygia pectinataria) | 1 |
| 1819 Mottled Pug (Eupithecia exiguata) | 2 |
| 1834 Common Pug (Eupithecia vulgata) | 1 |
| 1875 Small White Wave (Asthena albulata) | 2 |
| 1904 Scorched Wing (Plagodis dolabraria) | 1 |
| 1906 Brimstone Moth (Opisthograptis luteolata) | 1 |
| 1950 Brindled White-spot (Parectropis similaria) | 1 |
| 1961 Light Emerald (Campaea margaritata) | 2 |
| 1981 Poplar Hawk-moth (Laothoe populi) | 1 |
| 2028 Pale Tussock (Calliteara pudibunda) | 1 |
| 2064 Ruby Tiger (Phragmatobia fuliginosa) | 1 |
| 2092 Shuttle-shaped Dart (Agrotis puta) | 2 |
| 2380 Treble Lines (Charanyca trigrammica) | 1 |
| 2441 Silver Y (Autographa gamma) | 1 |
| Total Macros | 46 |
| GRAND TOTAL | 102 |
Birchanger Wood 