Author: David Bradley

UPDATE: 26 Aug 2022 – Convolvulus arrived to the tobacco plants in the garden after dusk. A rare sight in Cambridgeshire.

There are about 20 hawk-moths that you might come across in The British Isles, some far more often than others. Some are day-flying (diurnal), some night-flying (nocturnal), some drawn to light others preferring sweet nectar. These moths sit in the Sphingidae grouping, and are more generally known as Sphinx moths elsewhere.

 

 

The photos above are the nine hawk-moths we have seen in our garden over the last four years of mothing here. So, still plenty to “tick”, as it were.

Having spent a morning photographing Marbled White butterflies and Six-spot Burnet, Brassy Longhorn, and Burnet Companion moths on Trumpington Meadows near Cambridge I was inspired to travel slightly further afield to see if I could find any more interesting species of Lepidoptera. RSPB Hope Farm in Knapwell I remember had been productive on their pre-lockdown open days a few years ago and I remembered they had a wild patch of setaside.

Purple Hairstreak

The farm and reserve are not strictly open to the public at any time other than their open days, but it’s criss-crossed by public footpaths, so you can see some of the site if you’re discrete and don’t stray into the non-public areas. While there were plenty of Meadow Brown, Six-spot Burnet, Whites, and skippers on “wild” margins, unfortunately the wild area now has a crop and so any chance of a range of Lepidoptera beyond the obvious was not going to happen.

So, I hopped over to Overhall Grove, a small woodland not far from Hope Farm. It’s a bluebell wood in spring and also has the relatively Oxslip ( a hybrid flower formed by the fusion of cowslip and primrose). I was too late for those, of course, but I did bump into a couple – Nick & Stella Laughton – with cameras and scopes and binoculars who were staring at the top of an elm tree. Turns out the tree was host to White Letter Hairstreak butterfly. They were very friendly and full of ideas on where else I might see other butterflies, namely Woodwalton Fen National Nature Reserve and the Newmarket “July Racecourse” end of our local Devil’s Dyke. They also mentioned I should check out the Cambs & Essex Butterfly Conservation page, where people post their sightings.

UPDATE: I bumped into Nick and Stella at Brampton Wood just after the Black Hairstreaks emerged in mid-June 2023.

I took the trip to Woodwalton passing an antivivisection encampment on the way and ploughed on through to the Rothschild Bungalow. The oak trees on this site surrounding the bungalow are host to Purple Hairstreak (of which I saw at least a couple of dozen) and Purple Emperor (again maybe a dozen. One of the Purple Emperors had a perch high up in an oak on a prominent bough and would launch itself at any rival Emperors that flew too close. Indeed, it launched itself and saw off quite a few Emperor dragonflies too while I watched.

Devils’ Dyke was for another morning, this time with Mrs Sciencebase. Stepping out, we spotted a pristine (presumably newly emerged) Painted Lady (not many around this year) and then a host of Chalk Hill Blues, dozens and dozens, perhaps hundreds spanning a stretch of a couple of kilometres that we walked that morning. Also many dozens of Marbled White and an occasional Six-spot Burnet. Another couple spotted a Dingy Skipper, a species I’ve never wittingly seen, but we may have seen it that morning.

The Pyramidal Orchids were prominent but the much less common Lizard Orchids were past their best and we didn’t see those in bloom.

Another species that Stella and Neil had mentioned as being at Devil’s Dyke as well as the Chalkhills was hopefully going to be Dark Green Fritillary. We passed lots of other walkers who hadn’t seen any, but then before we know it, it’s noon and the Frits suddenly appear, perhaps half a dozen or so scattered along the Dyke and being chased by the Chalkhills.

A second visit to Woodwalton earlier in the day when the Purple Emperors were likely to be feeding on or near the ground was productive and I got snaps of that activity as well as a few better shots of the Purple Hairstreak.

So, having perhaps seen fewer than 30 species of butterfly in all my 50+ years, I suddenly “ticked” another five species in the space of a week – White Letter Hairstreak, Purple Hairstreak, Purple Emperors, Chalkhill Blue, Dark Green Fritillary. Earlier in the year I’d seen Green Hairstreak at Les King Wood and last year Silver-washed Fritillary and Clouded Yellow at Waresley Wood. I have to confess I’d seen SWF in Dorset and CY in Greece in 2019), but not seen them locally until 2020.

Some moths use pareidolia to scare away predators by flashing scary “eyes”, others disguise themselves as twigs, bark, lichen, moss. Some opt to look like leaves, yet others have more than a passing resemblance to flowers. Others spend a lowly life looking like bird droppings. This one, however, the Buff Arches, has evolved to resemble a chunk of flint lying on a woodland floor.

More moths on my Imaging Storm website  just follow the “Mothematics” menu

TL:DR – One can attract clearwing moths to one’s garden with focused planting or with synthetic pheromones.

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There is a beautiful group of moths known as clearwings that at first glance look rather waspish. Rather than having wings covered in scales like all of the other Lepidoptera (which roughly translates as scaly wings, or perhaps more strictly tiled wings), their wings a transparent, but for the supportive struts.

These are generally day-flying moths and look like tiny shimmering jewels if you catch sight of one. The males are attracted to sex pheromones exuded by the female. As such, it is possible to draw them to a lure impregnated with the appropriate sex pheromone for each species. The moths that arrive at the lure can then be counted and ticked, perhaps even photographed in the name of (citizen) science.

I purchased a set of pheromone lures from Anglian Lepidopterist Supplies ( a company that does exactly what it says in its name). I had previously used a lure for the Emperor moth with great success regular readers will recall. In the clearwing set there are lures for ten clearwing moth species. I began putting lures out individually on likely days – warm and breezy – back in May, but it is only into June that I’ve had success with the clearwings.

In early June, a Red-belted Clearwing was drawn to the target lure. By mid-June I was trying others and discovered that the lure for a different species, the Large Red-belted Clearwing drew in the smaller cousin – 14 of them, in fact! I put the lure out for the Hornet Moth next, no luck. Then, the  Currant Clearwing, success this time. Then I tried the Orange-tipped Clearwing lure, and drew in not the target species but a Yellow-legged Clearwing. Later, I learned from an expert name of Anthony Wren, that those two lures are identical in composition and now I am musing on what that says about the evolutionary history of these two species.

Clearly, the lures are not 100% on point when it comes to the species they attract. Now, ALS does list non-target species for each of its lures, so it is not entirely surprising. The reason is perhaps to do with the composition of the lures.

As I understand it, the lures each have the primary sex pheromone of the target female, but they also contain a mixture of other modified, volatile fatty acids and so on. This will lead to a degree of overlap in what the lure attracts because those other chemicals may well be interesting to other species of insect. It may not be about sexual attraction it could simply be that they are attractive or stimulating molecules. There does not seem to be a whole lot of clarity in the overall picture of what does what to each species yet, although there is a huge amount of excellent and ongoing research in this area.

 

Orange-tailed Clearwing (Synanthedon andrenaeformis) with its golden hair pencil turned up (2 or 3) at about 10am to the SYN lure in the garden on 16th June 2021.