Year: 2018

The Iron Prominent (Notodonta dromedarius) is fairly common across Great Britain, turned up in the trap a couple of times in the second week of August. Got better photos of the specimen on the morning of 13th where it sat on the back of my hand after jumping from its overnight resting place on a cardboard egg carton in the trap. It walked a little and then quickly fired up its wings to high-speed before flying off.

Two broods fly each year May-June and then again in August. Except in the North where they brood only once June-July, according to UKMoths. The humps on the green caterpillar’s back give rise to the second part of the scientific name. But, it’s the protruding tuft of hair on the trailing edge of the forewing in many species of the Notodonta moths that gives them the “prominent” of their common names. Although there are only four Notodontids in the UK, there are 3,800 known species in this family around the world, mostly in The Tropics.

Orange Swift (Triodia sylvina) – A first for the garden 13th August 2018 in three weeks or so of moth-ing with Rob’s homemade actinic Robinson trap.

Given how brightly coloured this specimen is compared to other photos of the species on UKMoths, for instance, I am assuming it is a male. The males are also smaller than the females, such sexual dimorphism does not seem to be a common trait in the moth world, although it does occur (viz some females are wingless and the Emperor Moth females are like a desaturated version of the male). The species is a member of the Hepialidae of which there are, it seems, only five members in the UK: Orange Swift (Triodia sylvina), Common Swift (Korscheltellus lupulina), Map-winged Swift (Korscheltellus fusconebulosa), Gold Swift (Phymatopus hecta), and the Ghost Moth (Hepialus humuli). Update: 11 May 2019, first Common Swift to the trap. Not seen any of these others yet.

The Orange Swift flies later in the year than the other Swifts, July-September (in the British Isles), so spotting one in the middle of August is about right, although UKMoths explains that it inhabits waste ground, moorland, and other wild places. Doesn’t say much for my gardening skills.

The larvae (caterpillars) feed on the roots of bracken, dandelion, dock, hop, and viper’s bugloss. It overwinters twice as a larva.

Night of 10th August 2018 saw a serious drop in temperature. We’ve been enjoying/sweltering in relatively balmy upper teens and into the 20s at night since May, but last night it dropped below 10 degrees Celsius in many places. The moth-ers are almost all reporting very few specimens in their traps. Personally, I had one Spectacle, a solitary Silver Y, a single Willow Beauty in the trap, and another on the white sheet hanging next to the light, and a few LBJs (Little Brown Jobs).

So here’s one of the highlights from a couple of weeks ago, a Canary-shouldered (Ennomos alniaria). It is a geometer moth (Geometridae) found across Europe. Geometers get their name from the behaviour of their larvae or caterpillars, which are whimsically also known as inchworms, their method of locomotion being reminiscent of someone measuring the earth. They’re also called loopers, for the “loop” the caterpillars form as they do their measuring.

In the UK, the adults breed in a single generation from July to September. They’re commonly found in woodland and gardens and the larvae eat the leaves of various deciduous trees. Indeed, the second part of its scientific binomial, the alniaria refers to the alder tree. The Ennominae are the largest sub-family of geometer moths, with some 9700 known species in 1100 genera.

TL:DR – Can moths fly in the rain? Some definitely can. I suspect many would prefer not to.

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9th August 2018 was the first proper day of rain in VC29 (Vice county Cambridgeshire) since May, there were a few spots and a bit of storminess earlier in the month, but a proper drizzle turned to a downpour yesterday. I was not holding out much hope of a night of mothing. So, I asked the members of the Moths UK Flying Tonight Facebook group thought about “lighting up” on a wet night.

First response was not a positive one: “Don’t bother if it’s raining, nothing much will be flying.” But, subsequent responders said that they “had some great moths on rainy nights!” And suggested it might be worth lighting up, after all.

“Some of my best catches have been on wet nights especially if it is drizzly and not too heavy…I have trapped on many a rainy night and had some of my best catches on them, I don’t usually bother if its heavy rain but drizzle to light rain is still worth it as long as not too windy I find…Moths don’t mind the rain. I’ve had some of my best nights during drizzle, even steady rain. As long as you waterproof everything you will be fine…It’s the wind, not the rain, that I find is dire for mothing..cold wet and windy being fatal.”

Another useful reply was to set up the trap under a white patio umbrella is you have one. “The moths came happily and perched under the umbrella as well as going into the trap.”

So after all that I let the moths make their choice and was rewarded with a few: Broad-bordered Yellow Underwing, Mother of Pearl, 3-4 Setaceous Hebrew Characters, a Turnip, 1 a Silver Y, and 4-5 unidentified micro moths. That was it. It was worth a try but I think the rain got heavier in the night and the wind picked up. I reckon I will set up on the garden table next time if it’s raining and put some white sheeting under our patio umbrella…