12 March, 2014

A (rubbish) Beginner's Guide to Spring Moths

Early spring is one of my favourite parts of the mothing year. Butterflies and moths are beginning to pop up all over the place; as can be said for a whole range of invertebrates that hibernate as adults, and providing a decent period of mild weather, a good range of species can be clocked up in March.

Even in the first few 'dark' months of 2014, I've been pleasantly surprised at the number of people actively searching for moths in their local area. The likes of Twitter and Facebook pages have been overflowing with enthusiasts reporting back on their early trapping sessions (no matter whether you catch twenty moths or absolute zilch, it's all data that recorders will cherish), which clearly reflects a wider expanding interest in this fascinating group of invertebrates that has taken place in the past couple of years. It really is great to see more people getting interested in the hobby, especially after the sad demise of the fantastic Back Garden Moths forum, which initially linked me up with knowledgeable enthusiasts throughout the country, and fuelled my interest in moths to a whole new level.

I don't have a permanent garden to run the moth trap in this spring what with Uni and such, but instead of sitting at a computer screen drooling at other people's catches, I thought I'd draw up a 'target list' of early season moths that one can expect to encounter in a typical garden in the coming weeks. Many of these moths might seem bleedingly obvious to a competent trapper, but everyone starts out somewhere, and I certainly found (and still find!) some of these species a struggle when I began trapping.

 The 'Micros'

(Left to right) Diurnea fagella, Emmelina monodactyla, Amblyptilia acanthadactyla, Tortricodes alternella

In terms of early season micros, I'd class these as the 'big four' (based on personal experience in the garden). Both Diurnea fagella and Tortricodes alternella are exclusively spring species, with nothing else on the wing at this time to mistake them for. The two 'Plume' moths fly throughout the year, and identification may become slightly trickier during the summer months when similarly obscure species appear. For now though, trap freely in the knowledge that a Plume moth caught in March/April is most likely to be either one of these species.

The Hiberators

(Left to right) Angle Shades, The Herald, Oak Nycteoline, Buttoned Snout

Rather than spend the winter in pupal form, these barmy moths overwinter as adults, emerging in March and April as the weather improves. Angle Shades and Heralds can often be found at rest in dark corners of your house, and are certainly up there in terms of distinctiveness. Oak Nycteoline is another species that can be found throughout the year, but could easily be overlooked as a large micro, particularly one of the Tortrix species. No two individuals are ever the same (in my experience anyway!) and it's best to look out for the relatively long 'snout' and furry legs that give this moth away as a 'macro'. Most specimens I've caught show- to some extent- a small (discal) spot half way down either wing. Talking about snouts, Buttoned Snout is classed as nationally scarce but is no doubt increasing its range throughout gardens in southern England. I find that the best method for finding these hibernators is to sweep through dense vegetation in the more sheltered areas of a garden. It could take a while to find, but is well worth the wait when you find one- stunning moths. Unless you're lucky enough to live along the coastal south-west where overwintering Bloxworth Snout come into the picture, identification of Buttoned Snout at this time of year isn't a problem.

The Pugs

(Left to right) Brindled Pug, Oak-tree Pug, Twenty-plume Moth (not a pug!)

The dreaded Pugs; a family full of species famous for looking exactly like the next species. March, April and to some extent May are the best times to get to grips with these, with only a small handful of species on the wing. Double-striped Pug is easy enough to identify, and can appear from January onwards. Fast forward a few months though, and your trap will soon be visited by the above two nondescript species. Telling them apart isn't easy, but as a general rule the discal spots (those two dark spots towards the top of each wing) are more prominent (wider, larger) in Oak-tree Pug, and usually only appear as slits on Brindled Pug. Brindled Pug is usually also larger, with less rounded wings than Oak-tree. Bear in mind that the two depicted in my photos above are prime examples of both species; be prepared to find intermediate and worn specimens which are best given a wave goodbye and sent on their way without being assigned to species. Typically in my garden, Brindled Pugs start to appear from late-March onwards, dominating trapping sessions until mid-April, when Oak-tree Pugs emerge in force and outnumber the former 3:1 generally until mid/late-May, when both species are on their last legs.

You've probably noticed that the final image isn't a pug, but a Twenty-plume Moth (Alucita hexadactyla). It looks distinctive enough when each of the 'plumes' are spread out, but in certain positions it could be mistaken for small pug- I've fallen into this trap a few times myself (literally, never check your moth trap when drunk, you might fall in).

The Beauties

(Left to right) Small Brindled Beauty, Brindled Beauty, Oak Beauty

As their name suggests, these early-season species really are beauties. The epitome of a 'fluffy moth', you'll know (and probably be able to hear) if you have an Oak Beauty in your moth trap. It's one of the most stunning species in the country at any time of year (fact), and a nice common one at that- all but the most ecologically dead gardens will have a good chance of accommodating this moth. Small Brindled Beauty is slightly less widely distributed, and has a surprisingly short flight period; emerging in late February, the species will reach a peak in early/mid-March before falling sharply in numbers to the end of the month, with very few individuals ever recorded in April. Brindled Beauty (the SBB's steriod-taking cousin) then picks up the baton and has a flight period throughout April until early May. As well as being twice the size of the former, Brindled Beauty has three distinct black cross-lines, and a less angled termen (the side of the wing furthest from the head).

The Chestnuts

(Left to right) The Chestnut, Dark Chestnut, Dotted Chestnut

Emerging as adults in autumn, Chestnuts (Conistra) are one of the few genera to actively fly during the coldest winter months, and as a result will often be the only moth to appear in my trap during December. The Chestnut is usually first to turn up in January, joined in February and March by the extremely similar Dark Chestnut. Indeed, both are so ridiculously similar that I only ever dare use external characteristics to identify well formed, fresh specimens. It is true that Dark Chestnuts (C. ligula) are generally dark, but variable examples of The Chestnut (C. vaccinii) can also be dark. The distinguishing features are all in the wing shape, with ligula showing a sharper apex (the lower edge of the forewing) than vaccinii's, which is blunt in comparison. This article by Steve Whitehouse summarises the differences well:

http://www.birdguides.com/webzine/article.asp?a=3135

Despite being fairly scarce and restricted in it's national distribution, the absolute gem of a moth that is the Dotted Chestnut is a very possible treat for garden in southern England with a good bit of deciduous woodland nearby. They hibernate in late autumn, reappearing in early spring according to the literature. I was lucky enough to catch the depicted individual in the garden on 5th May, so it's well worth keeping an eye out for this one all through the spring.

The Quakers

(Left to right) Common Quaker, Small Quaker, Twin-spotted Quaker

No matter where you are in the world, you can expect to catch a lot (and I mean a lot) of these throughout the spring. The genus Orthosia contains nine early-season species, including the very common Hebrew Character and Clouded Drab; for the purpose of this post though I'll stick with the three common species of Quaker. Common Quaker is typically one of the first to emerge in late February, with its warm brown colouration, and large distinct oval (top 'circle' on the wing) and kidney (bottom 'circle') markings. Small Quaker is just over half the size of the former, with a tiny oval mark in comparison to its kidney mark, and typically emerges in the first few weeks of March. The two species might seem a bit confusing at first- especially when caught separately- but are easy enough to get the hang of after a while, and look nothing like each other when side-by-side! Twin-spotted Quaker is another common garden species, easily identified by two (or more) sets of dark spots along the subterminal line.

Of course, the above is merely a smidgen of the total number of species flying at the moment. It seems evident that the relatively mild winter has already sped up emergence of many, so expect the unexpected. Whatever level of expertise you happen to be at, get out and enjoy the season ahead! I've set myself a few spring target species up here in Worcestershire (Blossom Underwing, Northern Drab and the Severn Valley specialist Silver Cloud to name but a few) so be sure to watch this space...

5 comments:

Peter said...

What a great post. Nice work - all new info to me as most moths are just too intimidating a group to start id'ing!

Ashley Beolens said...

Excellent article, really gives an idea of what to look for (some of the ones you mention would be new to my garden).

The mothing is already up and down in my garden this year (only trapped 3 times and all in March) with totals of 8, 29 + 10 (9 species so far). But I do love waking to see what will be in the trap.

Jason K said...

A really interesting and informative post Bill

oldbilluk said...

Bill, a useful addition to this would be to have a few photographs of worn specimens of the same moths so that beginners get an idea of the range of "looks" they need to deal with. Great post though and very helpful to us old folk who are beginning to forget from one year to the next :-)

Billy Dykes said...

Peter- Thanks. Keep at it and you'll be flying in no time- anyone who can ID birds can ID moths!

Ashley- Cheers mate. It's been a mild March so far, and I'd expect your species total will very much increase by the end of the month.

Jason- Cheers, thanks for stopping by!

Bill- That would have been a great idea, but unfortunately my photo archive says otherwise... ;-)