You will have spotted by now, my current fixation on the Emperor moth, Saturnia pavonia. It’s Britain’s only resident member of the Saturniidae family (related to the Silkworm moth). I have a pheromone lure that has some (6Z,11Z)-hexadeca-6,11-dien-1-yl acetate on it, which I bought from Anglian Lepidopterist Supplies. UPDATE: As of 2023, fifth season of checking on this species in our neighbourhood, still present and showing.
Male Emperor moth, Saturnia pavonia
It took me a while to track down the name of that sex pheromone, exuded by the less colourful, night-flying females, to attract the colourful, day-flying males. I had photographed one or two on the wing but used a homemade butterfly net to catch the specimen you see above. I let it chill out in a pot for a few minutes to get a nice snap showing all of his pareidoliac eyes and his enormous pheromone-detecting antennae without him flapping about.
He’s back in the wild now looking for true love rather than olfactory moth porn. Neither the male nor the female has mouthparts, so they cannot eat, they get all their energy from reserves built up when they were larvae (caterpillars) eating heather or brambles. They have to get it together as soon as they can during the flight time of April to May.
Now, who said moths were grey and dowdy? This is surely the most photogenic moth in the UK.
It’s always amusing to hear someone say “there’s not much about” when you’re working your way through a nature reserve. Depends on what you mean by not much…I only saw the following at RSPB Ouse Fen this morning:
Willow Warbler Chiffchaff
White Throat
Blackcap, Swallow
Sandmartins
Chaffinch
House Sparrow
Rook
Carrion Crow
Greylag Geese and Goslings
Green Woodpecker
Buzzard
Marsh Harrier
Kestrel
Bittern
Great Black-backed Gull
Lesser Black-backed Gull
Black-headed Gull
Mallard
I made a rookie research error. Saturnia pavonia, the Emperor Moth, was previously known as Pavonia pavonia, and in my search for the chemical identity of its sex pheromone (which is in the moth lure I mentioned previously) I’d assumed these were its only names. But, apparently, it was also known as Eudia pavonia.
Once I’d realised this, a scientific literature search quickly found a paper discussing the moth’s sex pheromone: (Z)-6,(Z)-11-hexadecadien-1-yl acetate. This is closely related to another chemical gossyplure, a 1:1 mixture of the (Z,E) and (Z,Z) isomers of hexadeca-7,11-dien-1-yl-acetate. That chemical is used commercially to lure cotton-infesting moths to traps to reduce breeding of different species Pectinophora gossypiella.
So, with the systematic name, I could get the InChI string from one converter and then generate a chemical structure, so here it is together with the male moth I photographed, which is attracted to this chemical:
UPDATE: 9th April 2020: First Muslin to the lure, conventionally photographed from three angles on stone.
The male Muslin Moth (Diaphora mendica [Clerck, 1759]) that I saw in the trap these last couple of mornings was there again today. I know, because he has a little snick out of the end of his left antenna. I was hoping a female might turn up, their wings are muslin-white, but the only other moth in the trap was a solitary Hebrew Character.
Muslin Moth
Anyway, the Muslin’s arrival gave me the opportunity to try out some more focus stacking. This time I used a couple of free tools. The first a controller for my Canon dSLR, digiCam Control. This software lets you control you dSLR via a USB cable from your computer and has builtin focus stacking (and many other functions).
I used its simple focus stacking to take a focus-bracketed set of four photos of the moth illuminated with an LED ring flash and natural light from my “studio” window (it’s just our back bedroom, which I use as an office). Anyway, each of the four photographs has its focus from near to far away from the camera. So the moth is pin sharp in each photo but only in a certain plane parallel to the camera’s sensor. The depth-of-field is very short with a macro lens at close quarters even with a small-ish aperture of f/9.5.
I then combined (automated process) the four shots using another piece of free software, CombineZP. I used what seemed to be the simplest option “Do Stack” and the resulting composite image was generated in a couple of minutes.
All very quick and easy. I am sure with practice and more attention to the details of optimising each piece of software and perhaps the lighting for the subject, I reckon it would be possible to get even better sharper shots, without having to spend hundreds of pounds on new hardware.
I also did a sequence of face-on portrait shots with the moth, automatically aligned them in CombineZP and then applied the “Do Stack” command, great result.
Focus stacked moth, note how from nose to tail the image is largely in focus
Focus stacking involves taking essentially the same photo several times but focusing first on the foreground, then the mid, then the farthest point on the subject. You can take as many shots as you like to “bracket” the image and get a sequence of shots that have the whole of the object in focus at some point in each photo. As you can see in the photo above.
It works best if you set the camera up on a tripod and take the series of photos using magnified LiveView and manually focusing on different parts of the subject. There are automated systems (software and hardware) and some cameras have focus bracketing built in (think of it as the focusing analogue of exposure bracketing, which lets you create high dynamic range (HDR) photos.
Once you have your set of focus-bracketed photos, you can then use a photo editor to blend them into a single composite image where pretty much all of the shot is in focus. The technique overcomes the very shallow depth-of-field you have with a small aperture when shooting taking close-ups. That said, the technique works to extend DoF for any type of photo.
Today’s subject is the beautifully patterned Angle Shades moth (who said moths were dull and grey?). I had it sat in a pot and perched that on an old patterned chair. If I could have persuaded it out of the pot without it flying away, you could have seen better just how well camouflaged this moth is against such William Morris style arts and crafts prints. In the wild, of course, it finds itself beautifully camouflaged among multicoloured and dappled foliage.
It has been a bit quiet on the new-to-the-garden moths, basically because it’s still quite cold and the night-flyers aren’t out in great numbers yet. Nevertheless, a male Muslin moth (Diaphora mendica) turned up last night. Hashtag #floof. Here he is “focus stacked” using half a dozen macro close-ups and Zerene Stacker. The aerial view is a single shot.
The females don’t have the big pheromone antennae and are white with the black spots.
The other moths that are around and that have turned up in varying numbers in the last month or so include: Common Quaker, Small Quaker, Twin-spotted Quaker, Hebrew Character, Clouded Drab, Early Grey, Twenty Plume, Common Plume, Early Thorn, Garden Carpet, Nut-tree Tussock, Agonopterix yeatiana, March Moth, The Chestnut, Double-striped Pug, March Dagger, Dotted Border, Pale Pinion, Oak Beauty, Pale Brindled Beauty, Acleris cristana.
Photos of all these updated with the new entries can be found in my Mothematics gallery on Imaging Storm, also includes butterflies, but they’re really just a type of moth, anyway.
This blog post isn’t about some supernatural Geordie, rather a species of owl that haunts the northern parts of the Americas and Eurasia- the Great Grey Owl (Strix nebulosa). It’s the largest species of owl we have, by length, although ignore the feathers and it isn’t quite so impressive looking, but then which bird is? Also known as the cinereous owl, spectral owl, Lapland owl, spruce owl, bearded owl, and sooty owl.
The Phantom of the North, photo by dB/ at Linton Zoo, Cambs, 7 Apr 2016
The sub-species S. n. nebulosa flies from central Alaska eastward across Canada to south-western Quebec, and south to northern California, northern Idaho, western Montana, Wyoming and north-eastern Minnesota. S. n. lapponica can be found in Fennoscandia through Siberia to Sakhalin and Kamchatka Krai to Lithuania, Lake Baikal, Kazakhstan, Mongolia, Manchuria and north-eastern China.
Cross section showing the extent of body plumage of S nebulosa
There are more than 11,000 extant species of bird around the world, they all evolved from the theropod dinosaurs of which Tyrannosaurus rex is perhgaps the most famous. They are a seemingly diverse bunch of animals from the tiny Firecrest and the Hummingbirds to the Emu and Ostrich by way of the Vultures and the Cockatoo.
Wheatear
There are 137 families of perching birds, the so-called passerine birds, which have three toes pointing forward and one pointing back. The Passeriformes account for almost two-thirds of all bird species and are found across the globe. The term passerine comes from the Latin word for that archetypal perching bird, the House Sparrow (Passer domesticus). Passero or passera is Italian for Sparrow.
Anyway, a new DNA analysis reveals that all of those thousands of species of Passeriformes have a common ancestor that lived 47 million years ago in Australia. Discussed in more detail by Eleanor Imster in EarthSky.
Meanwhile, a genetic analysis in Science this week, explains why that Australian resident, the Emu, and indeed Ostriches and other ratite birds cannot fly.
I seem to have inadvertently duplicated this article and then edited it. The original with my garden “list” can be found here.
Reader John S asked me to put together a report on the topic of what birds we are likely to see in our gardens here in the village of Cottenham a few miles north of Cambridge. I suspect there are a few of you who will have spent an hour back in January counting species for the RSPB’s Big Garden Birdwatch and so hopefully there are others would be interested to know what they might see.
Redpoll
Of course, which of our feathered friends turns up in your garden is down to many different factors, the size and layout of your garden, tree and other plant species, the presence of cats, whereabouts you are relative to patches of woodland, farmland, and whether or not the visitors find a useful supply of food in the form of berries on your bushes, seed feeders and bird tables, coconut shells full of suet, and whatever else you might put out to attract them.
Blue Tit
Some birds will arrive in great numbers to feast on fatballs for instance. Most of us have been perplexed to see expensive fatballs disappear in a matter of minutes when a flock of starlings turn up. Other food, such as nyjer seeds in a specialist feeder will draw in Goldfinches and occasionally for some Redpolls. Sunflowers seeds with the husk intact, sometimes referred to as black sunflower hearts, will keep Greenfinches, Blue Tits, Great Tits, Coal Tits, and Long-tailed Tits busy, and if the nyjer seeds run out the Goldfinches too.
Wren
Robins, Blackbirds, Wood Pigeons, Collared Doves, Dunnocks, will spend much of their time pecking around under the feeders, although the Blackbirds will join Mistle and Song Thrushes plucking insects from the lawn. And, Thrushes will famously grab snail shells and smash them on the ground to get at the occupant. If it’s very cold out on the farmland, the winter thrushes – the Fieldfares and Redwings – will come into the warmer more urban areas and attempt to snaffle berries from your bushes and trees much to the consternation of the Blackbirds who will attempt to make them flee.
You might also spot Bramblings during the winter. They are another finch resembling the Chaffinch but brighter and more orange colours. I have heard from people on Broad Lane who see them in their gardens occasionally, but they are more likely to be elsewhere.
Unusual but increasingly common in the winter are Blackcaps, a type of warbler normally considered a summer visitor, but turning up in our gardens from Germany and Eastern Europe rather than heading to the Iberian Peninsula and North Africa. Speaking of summer, by the time you read this birds that you might see above your garden or heading into your eaves may have started to arrive: House Martins first, then the Swallows that don’t necessarily a summer make, and finally the Swifts. Listen out for Cuckoos too. Certainly houses on The Green backing onto farmland have regular cuckoos visiting for the breeding season.
If you have ants among your plants, you might see Green Woodpeckers, also known as Yaffles for their scoffing call in flight. Ants are the Yaffle’s staple diet, so hold off the powder if you want to see them pecking at the ground in your garden. And, speaking of woodpeckers, there are quite a few Great Spotted Woodpeckers around, which will often come to garden feeders. Of course, if you’re attracting lots of small songbirds to your garden you might also attract predators including Sparrowhawks and less obviously egg-eating Magpies, and chick-chomping Jays. Great Spotted Woodpeckers will also peck into birdboxes to eat baby Blue Tits and the like.
Another reader, Diana S, also pointed out that she’d had Reed Buntings in her garden and had seen Little Grebe and Teal on the reedy pond at the back of her housing estate.
Well, actually Toads of Anglesey Abbey. Common Toad (Bufo bufo) spawning in the bird-hide pond on the National Trust site in Lode, Cambridgeshire. Note, the toad spawn looks like a necklace of black beads on a string, whereas frogspawn forms in clumps. That said, there’s no real distinction between toads and frogs. Toads are just a type of frog (Bufonidae), just as butterflies are a type of moth.
These photos were taken at NT Anglesey Abbey on 21st March 2019. The spawning may well be over by now. There was also a Water Rail present on the opposite side of the pond.
