Category: Science

Having written about one of the bigger moths we see in the UK, Connie, the migrant Convolvulus Hawk-moth, it only seems fair to give a mention to a micro, as opposed to macro moth. So, here’s the Garden Rose Tortrix.

Now, the macro versus micro label may well have been historically about size. The larger moths being macro, the smaller moths being micro, as you might imagine, but there are so many enormous micro moths and so many tiny macro moths in the world that this really doesn’t hold. In fact, the division is one of evolutionary history, the micro moths being a much older grouping.

The micro grouping includes all of the butterflies, which are essentially just a family of micro moths. The only physiological difference between what British English thinks of as butterflies and moths is that the butterflies cannot unhook their forewings from their hindwings. That’s it. Asking what’s the difference between a butterfly and a moth is like asking what’s the difference between a ladybird and a beetle, or a dog and a mammal…

Anyway, back to today’s micro. This tiny two-toned moth is known as a Garden Rose Tortrix, Acleris variegana. It is one of about 11000 worldwide moths that are members of the tortrix family, the Tortricidae. They’re so-called because their larvae roll themselves up in a leaf to pupate and metamorphose into the winged, adult. The word tortrix has the same etymology as the word torque, the word for a twisting force – torquere, meaning to twist.

As regular Sciencebase readers will know by now, this once workaholic science writer is now a highly dedicated mother. As in I am an enthusiastic amateur Lepidopterist. A moth-er, like a bird-er, birder, someone keen to see, observe, understand, and perhaps photograph the subject. This year and last, I’ve also been a bit more focused on being a butterflyer too.

Anyway, part of being a mother usually involves finding ways to see moths. Commonly that involves some kind of lure – a pheromone bung or an ultraviolet (or other) light. And, again, as you will know, I’ve got several lures for enticing moths for observation and the inevitable photoshoot. At the time of writing, I’ve lured and photographed about 450 moths of the 2600 species found in the UK.

The standard approach to nocturnal mothing is to have a box above which a bright light or bright UV source is suspended, often above a funnel or vent. Moths are drawn to the lamp, like moths to a flame but without the fire risk. They might circulate a while and will often spiral or dive into the funnel opening or the vent and then find it rather difficult to navigate their way out again. A good mother will have pre-filled the trap with lots of empty cardboard egg trays. The trapped moths will settle down in the nooks and crannies of these trays for the night ready to be logged and photographed in the morning.

Moth-trap lamps do not only attract moths, beetles, flies, wasps, hornets, worms, snails, slugs, all kinds of creatures will be drawn. But, it also seems so will the larvae of moths, the caterpillars. A few mornings back, while logging the night’s moth haul (before release into undergrowth away from the garden) I found in one of the egg trays, a couple of caterpillars, larvae of the Toadflax Brocade moth. They must have wriggled all the way from the other side of the garden, about 12 metres where there is a patch of Purple Toadflax or perhaps 15 metres from the Common Toadflax (Butter-and-Eggs) patch to the patio whereupon the moth trap sits on lighting-up nights.

The two larvae were pupating and using tiny fragments of the cardboard egg tray to make their protective cocoon. One had made a good start and was almost completely enclosed ready for its metamorphosis, the other had a long way to go and so was still very exposed and so obviously a Toadflax Brocade larva. I’ve relocated the egg tray to an under-cover bench outside the garden shed where hopefully the two will finish their transformation and emerge at some point in 2023 as adult moths. I’ll keep you informed as to their progress if anything changes in the meantime.

TL:DR – The Convolvulus Hawk-moth is an infrequent visitor to British gardens, but they do occasionally turn up, having crossed the channel, and there is evidence of breeding here, but not over-wintering yet. Several were attracted to Nicotiana I grew especially for them.

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UPDATE: 8 Sep 2024 Finally, annother Connie, no Nicotiana, just turned up, hung around the wisteria, flew off.

UPDATE: 1 Sep 2022 Another arrived in the garden tonight less than a week after the first, it nectared on the still blooming Nicotiana before diving into the actinic moth trap. I lifted the lid to let it out and it soured away into the night sky, like a whirring wraith in a pink and black stripey mohair rollneck.

The Convolvulus Hawk-moth, named for its larval food plant convolvulus (bindweed) and its hawk-like appearance, is a relatively rare visitor to the UK from mainland Europe.

The books usually say it migrates rarely and will be seen only in the South West of England if it does, but it has appeared elsewhere, often carried in on the same weather as other migrants, such as the Hummingbird Hawk-moth. There’s also the likelihood of the offspring of Spring migrants appearing as adults in the late summer.

The species’ wingspan can be 85 to 120 millimetres, as big as the British Privet Hawk-moth and with those pink and black stripes it’s almost like a close cousin.

The Convolvulus Hawk-moth likes to nectar on tobacco plants and ginger lilies among other flowers and I have been growing the former in our back garden since I started mothing in the hope of seeing a Convolvulus. After our trip to the New Forest with the LepiLED,* I reverted to my trusty 40W actinic trap next to the tobacco plants for the first evening lighting up back home. Within 20 minutes or so I could hear a whirring, humming insect near the plants and with a torch caught site of it with its huge compound eyes glowing like embers in the air. It did not stay long and flew off over neighbouring gardens. I mused on it being another migrant, perhaps a Striped Hawk-moth of which there had been many recent reports across East Anglia and the southern counties, but this moth was bigger, a lot bigger.

I could confirm the Convolvulus ID when it (presumably the same insect) made another appearance in the garden five minutes later. There have been several reports of Convolvulus in the county this year already, so this wasn’t the first.

The one in our garden, sucked a little nectar from the flowers of the garden tobacco plants before heading for the UV lamp and diving into the trap. I quickly took the trap indoors and got setup for a photoshoot. I snapped a few closeups of this beautiful moth before releasing it back to the night air.

As you can see from my photos it has some of the character of the Privet Hawk-moth, another member of the Sphingidae (what the Americans call Sphinx moths as opposed to Hawk-moths). Wingspan can be between 85 and 120mm, this one, I estimated was about 110mm across.

Convolvulus often appears alongside other migrants. It has been a particularly good summer for the distant, much smaller cousin, the Hummingbird Hawk-moth, as I’ve mentioned here and on Twitter, Facebook, and Instagram. The Striped Hawk-moth has been reported widely, and I am still hoping that one will turn up here, it would be a grand end to our holiday period if it were to join the Convolvulus in making a late Summer appearance.

*The holiday mothing was limited to lighting up with the LepiLED and logging the Lepidoptera in the morning, most of our adventures were out and about in the local countryside and on the coast. The more general photos from our trip will appear in good time, but right now I am focused on the Convolvulus.

FINAL UPDATE: Back home, checked through the records. 12 species I’d not seen before, at least two of which are usually confined to the South coast and hinterland.

The list of moths I’d not photographed before our New Forest 2022 trip is as follows: Black Arches, Chequered Fruit-tree Tortrix, Cydia amplana, Dusky Thorn, Hedge Rustic, Lesser Swallow Prominent, Lesser Treble Bar, Light Crimson Underwing, Plain Wave, Dark-barred Twin-spot Carpet, Rosy Footman, Six-striped Rustic.

Records now dispatched to Hampshire County Moth Recorder, Mike Wall.

UPDATE: Seventh Night: A warm and dry night, 60 or so moths of 26 species, including one final new for me: Small Square-spot.

UPDATE: Sixth Night. Started off rather dry and balmy, I’d lit up before we left the holiday house for the pub and there was quite a lot of European Hornets hanging around when we got back well after dark. I also caught sight of a Rosy Footman (new for me), a Light Emerald, and a few veneers. But, it started raining heavily during the night.

By Thursday morning there was quite a lot of water in the trap and the egg cartons were soaked, there were still 40 moths of 23 species, with two or three escapees that eluded identification. Once again a few clipped wings present suggesting that the local Robins had been dining at the trap after dawn too.

I managed to fish out the Rosy Footman and another new for me, Light Crimson Underwing (this completes the set of Catocala underwings I’ve photographed). There’s a short video clip of the LCUW on the Sciencebase Instagram, with Going to the Chapel as the background music for good reason given the scientific names of these large underwing moths.

UPDATE: Fifth night. Cool, but not wet. About six moths of 23 species. Some new for the week, like Yellow Shell, Straw Underwing, Mother of Pearl, and Canary-shouldered Thorn. Also, new for me Dark-barred Twin-spot Carpet (very worn, most likely Dark-barred than Red though) and Hedge Rustic. Numerous clipped wings in the trap and bird droppings on the top from avian activity.

UPDATE: Fourth night. Drizzly night, around 70 moths of 30 species. Probably overlooked a couple but also had my first Dusky Thorn and Lesser Swallow Prominent, numerous Small Bloo-vein, lots of Flounced Rustic and Agriphila tristella again, and at least a dozen Red-legged Shield Bug.

UPDATE: Third night numbers were down a lot, but there was still a Buff Footman, another Jersey Tiger, Oak Hook-tip, and a Plain Wave (NFM) and various others (mainly Agriphila tristella and Flounced Rustic). Added some video of the Jersey Tiger to my Instagram with a snippet of appropriate ABBA.

UPDATE: Second night of lighting up, quite a lot more moths around 40-50, including Black Arches (3, NFM), Jersey Tiger (2), Light Emerald (6), Maiden’s Blush, also a European Hornet.

First night off-site with the LepiLED and a portable Robinson-type moth trap was in North Poulner in the New Forest. We ate fairly late but there were Pipistrelle bats circling the trees in the garden overlooking the valley long before dusk felel.

I lit up with the trap right under an oak tree, I had high hopes. Numbers weren’t huge, but there were a couple of species I had not seen before – Six-striped Rustic (Xestia sexstrigata, one of the many noctuid, or owlet moths) and Chequered Fruit-tree Tortrix (Pandemis corylana). The latter is also known as the Hazel Tortrix Moth, the Filbert Tortricid or the Barred Fruit-tree moth and sits within the Tortricidae family.

Full list for the first lit-up night was: Brimstone, Chequered Fruit-tree Tortrix (NFM), Chrysoteuchia culmella (6), Flame Shoulder, Lesser Broad-bordered Yellow Underwing (2), Light Emerald (3),  Maiden’s Blush, Rosie Rustic, Six-striped Rustic (2, NFM).

Just to note, when I got up in the middle of the night and took a breath of fresh air, as it were, there was a fox trotting slowly past the moth trap in the relative dark, I don’t think it even saw me standing there, certainly didn’t seem perturbed.

I didn’t have my usual macro kit and “studio” with me, so just basic record shots of the new moths taken with my phone camera or non-macro SLR lens. Note to self: take macro lens and tripod and LED staging kit and flashgun on next trip or regret it!

UPDATE: 2 Sep 2022 We (I) took the LepiLED with a portable trap to the New Forest in August and added 12 or so moths to the list, when we returned from our trip, first night lighting up we saw a Convolvulus Hawk-moth turn up to nectar on the Nicotiana (garden tobacco plants) before diving into the home garden moth trap. Another turned up later that evening and another on night of 1st September.

It was four years in July 2022 that I had been mothing in our back garden with a 40W actinic/UV trap. In that time I’ve photographed well over 400 species of macro and micro moth. I keep logs for the County Moth Recorder, so it’s not only a photographic venture it’s citizen science too.

By 2020/2021 I felt like I had probably seen most of the species of moth that are in this area, but there are always surprises that turn up and in those years there were 31 and 37 species that turned up that I hadn’t seen before. It’s the middle of August and so far in 2022, I have logged well over 300 species in the garden (and elsewhere as noted) this year, with 45 of them being species new to me.

You can find photos of all these species in my Lepidoptera galleries over on my Imaging Storm website. Photos of 47 species of butterfly and 460 moths as of 1st September 2022.

*NF = New Forest

I have put in a bit of effort to see more butterfly species over the last couple of years. Not travelling much farther than local nature reserves but homing in on ancient woodlands and sites where a few target species are known to thrive. So here are my lifers, six this year, six last year, several others in the year or two before that I’ve not listed.

I should perhaps add that I was first to log two new butterfly colonies – White-letter Hairstreak in Manor Farm Wood, Rampton and not far from there a colony of Purple Hairstreak on an ash tree close to the Cottenham Lode. I was also first to log a large number of Clouded Yellow (perhaps as many as two dozen) on a wildflower meadow along the Earith Bridleway just as you step off RSPB Ouse Fen close to the River Great Ouse.

My butterfly photo gallery is available on my Imaging Storm website where you can see my photos of all of the species mentioned above and more. Follow me on Instagram for more Lepidoptera as they emerge.

I had my first Lymantria dispar sighting of the year in the garden last night. He was very battered and worn and had a chunk missing from his left wing. As such, I let him on his way without potting him to photograph and then release. So this is perhaps one of his ancestors photographed on my finger last year!

There’s a call in the US to remove inappropriate vernacular names for organisms and such from the textbooks. So, Stateside the moth is now often referred to as the Spongy Moth. The proposed name comes from the common name used in France and French-speaking Canada, Spongieuse, and alludes to the spongy mass of eggs laid by the females.

Incidentally, Geoffrey de Havilland was an amateur Lepidopterist, hence many of the names he gave his aircraft referring to moths, Tiger Moth, Gypsy Moth etc. I doubt there will be a name change of those vintage aircraft though.

Anyway, we always have the pseudo Latin scientific binomial, Lymantria dispar, to fall back on. I am not entirely sure whether that is a more politically correct name than the original English name of this species because it loosely translates as the “sexually dimorphic destroyer”.

Lymantria dispar is commonly still known as the Gypsy Moth in the UK, a name with racist connotations, hence the need to adopt an alternative vernacular name for the species.

In my effort to add some “wild” patches to our garden, I’ve got a lot of yarrow growing this year. A Yarrow Pug, Eupithecia millefoliata, turned up in the garden last night. This moth brings the new for me total for 2022 to 38 so far. I’ve logged 280 species of moth in the garden this year; not including the butterflies.

The Yarrow Pug is quite a scarce species only been in the British Isles since the 1930s. Usually, only seen on the south coast from Essex to Dorset but it’s spread along both sides of the Thames Estuary and beyond. First recorded here in Cambridgeshire in 1978. Pugs have that name because the naturalists thought the shape of their wings resembled the jowls of the breed of dog known as a pug!

Also new for me (NFM) last night was this tiniest of tiny moths, the Apple Leaf Miner, Lyonetia clarkella. Where the larges of the native, breeding moths in the UK, the Privet Hawk-moth can have a wingspan of up to about 120 millilimetres, L. clarkella has a wing span of a mere 8 mm or so. This particular specimen seemed even smaller than that. The larvae of leaf miners burrow through leaves eating as they go and leaving a trail behind them.

*Butterflies in the garden this year: Brimstone, Comma, Common Blue, European Peacock, Gatekeeper, Green-veined White, Holly Blue, Large Skipper, Large White, Marbled White, Meadow Brown, Orange-tip, Red Admiral, Small Copper, Small Tortoiseshell, Small White. For all my moth and butterfly photos check out the galleries on my Imaging Storm website.

In the summer of 2020, just after the first covid lockdown, I visited Waresley Wood, which is a few miles west of the city of Cambridge. The wood itself is good for Silver-washed Fritillary and the adjacent Brown’s Piece has plenty of Marbled White. That summer, there was a small patch of meadowland next to a maize crop where Common Blue and Brown Argus danced among clover, borage, viper’s bugloss and vetch.

On that visit, I also spotted a couple of fast-moving and vivid butterflies chasing up and down this ad hoc meadow. They were Clouded Yellow butterflies, Colias croceus. The species is quite rare in the British Isles and if you see one here it will usually be a migrant that’s flown in on an Easterly breeze from continental Europe. Some years we do get irruptions, mass immigrations, where they arrive in relatively large numbers in the summer and breed.

As to why they are so fast moving compared to some other related species, such as the “cabbage” whites, the Clouded Yellow does not accumulate toxins from the plants it eats. Where the Whites are often unpalatable to predators, such as birds, the Clouded Yellow is a tasty little morsel. However, while the more sedate Whites have poisons on their side to protect them, the Clouded Yellow has speed. It rarely sits still for more than a fleeting moment, as my good friend and fellow amateur wildlife photographer, Andy Hoy will attest. In between those rare rests it moves seemingly erratically and at speeds much greater than any White, or indeed any of the other butterflies you might see sharing the nectar of a wildflower meadow.

The Clouded Yellow will favour clovers growing on unimproved chalk downland, so that’s kind of terrain is a good place to look for them, especially in a “Clouded Yellow Year”. At the time of writing, Andy had spotted a solitary Clouded Yellow on a local reserve, without much forethought we shared a hike in a neighbouring patch and took a detour towards the end of the walk in the hope of catching sight of a few butterflies. We were expecting Common Blue, Brown Argus, European Peacock, Gatekeeper, Meadow Brown, and the aforementioned Whites, Large and Small, and were duly rewarded.

The hope of a Clouded Yellow or two was rewarded as we walked a 60×250 metre patch of wildflower meadow with plenty of clover, vetches, ragwort, sow thistle and other nectar-rich flowers on the edge of a wheat field. Glass half-full, I reckon we saw a couple of dozen Clouded Yellow, whereas Andy reckons it was perhaps a dozen. It could be that some of the same individuals were counted more than once. I asked the County Butterfly Recorder, Edward Pollard, for his opinion on this point, following his advice and being a little more half-empty than my I’d like to be, I’ll record perhaps 15 or so individuals but with a margin of error of about 5 or 6.

TL:DR – Purple Hairstreak butterflies are present in Gamlingay Woods in the summer along with Purple Emperor and various other species.

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I’ve visited a few of the old woods to the west of Cambridge in the last couple of years including Hayley Wood, Wareseley Wood (and Brown’s Piece), and Overhall Grove. One that I’d attempted to visit this time last year was Gamlingay Wood. It’s not far from the village of Waresely, and for that matter, not far from Gamlingay.

Google Maps gets you to what it thinks is your destination at a farm gate on the B1040 road. Unfortunately, this isn’t the nature reserve managed by the Wildlife Trust. That’s further along the road up a gated track, there’s no parking now, and the nature reserve sign that was apparently opposite the track and the erstwhile parking is missing.

Anyway, I was visiting as this is another site with some old oaks and a sighting of Purple Emperor butterfly. So, I found a layby back up the road, parked there and walked back down to the sign that isn’t there and up the gated dirt track. There’s a Y in the footpaths when you go through the accessible style-gate and after a quick look to the tops of the oaks there, I took the right fork and then a sharp left to cut across the woodland. Within 100 metres or so I spotted a Purple Hairstreak fleetingly basking on the ground.

So I hunkered down with my camera and macro lens and watched for more. There were plenty. Perhaps a couple of dozen. Interspersed with Silver-washed Fritillary, Large White, Ringlet, Large Skipper, Speckled Wood, Gatekeeper, Comma, and Meadow Brown. I was just about to move on, when a Purple Emperor wafted towards me and flew overhead never to be seen again. I lugged camera and camera bag a little further into the wood, saw more Frits and lots of Peacock nectaring on Purple Loosestrife, there were insects on Chichory flowers, and an occasional moth, and at least a couple of Brown Argus in a scrubby clearing. All nice enough to see, but I was peeved that I didn’t get a snapshot of Gamlingay’s Purple Emperor. That will have to be for another day.