When I checked the moth trap on the morning of August the 2nd, there weren’t as many moths as there usually is. However, there were many species I’ve never seen before, including three species of Thorns. Thorns can be identified by the way they hold their wings – not flat like most moths but angled upwards.
The first species of Thorn I found by the trap was the Purple Thorn, which was resting on the sheet. It’s a pretty large moth, the individual I caught had a wingspan of 34mm. However that’s not the species’ maximum wingspan. The Purple Thorn has two broods (generations) each year, the first flying in April and May and the second flying in July and August. The first brood has a larger wingspan, whereas the second has a smaller wingspan, and the moth we caught was from the second brood. The species is fairly common in the south, and prefers habitats like woodland and heathland. However, it gets scarcer as you move northwards. It is patchily distributed in Scotland, with the main stronghold being around the Moray Firth. It’s common in Wales, but practically absent from Ireland.
The second species found, the Canary-shouldered Thorn, was perched on the metal bit which holds up the bulb. It’s the prettiest species we caught, with a bright canary-yellow thorax and yellowy-orange wings. It is also the largest species, even larger than the Purple Thorn, and it also only has one generation. It’s widespread throughout the UK, from Cornwall to Orkney, although like the Purple Thorn, it’s scarcer in Scotland. However, this might be because there are fewer recorders up in the highlands, and there are many concentrated around the South-East (like me). The Canary-shouldered Thorn can also be found in Northern Ireland and even the Isle of Man.
The last Thorn species is called the Early Thorn. It’s by far the smallest species and, like the Purple Thorn, has two broods each year. We caught an individual from the second brood which flies from August-September. The first flies from April-May. Even though it might be the smallest, it’s the most widely distributed, being found on Scilly as well as England, Northern Ireland, Wales, Scotland (including Orkney) and the Isle of Man. It’s identifiable by the way it holds its wings, flat above the body like a butterfly. A melanic (dark) form of this species is fairly common in Northern England, but rare down here in the South.
The reason we put the moth trap out was because I had an event planned for the following morning. I thought that as I lived in a small, quiet village it would be nice to teach the people who live in my village a little bit about the moths found in their area. I invited all the people I knew from the village and was pleasantly surprised that quite a few people decided to come! I even got a few to sign up to my monthly natural history newsletter, which I will be writing for the residents.