The Topsham Naturalist

A blog about birds, insects, in fact any kind of wildlife. Mostly around Topsham, Devon. Photos, sketches and illustrations.

Thursday, 11 April 2013

New Blog

On the very slim chance that anyone is reading this, I have a new blog The Two Bird Theory. Let's see if I can keep the new one running a little longer....Tim.

Friday, 20 August 2010

Learning to fly

It's been far too long since anything new appeared here - must try harder!

In spite of yesterday's forecast rain we took a chance and had a fine walk along the coast path east of  Sidmouth. The cliff at Weston Mouth was hosting a beginners flying club of Ravens, a dozen or more juveniles trying out their skills in the gusting wind and updraughts.



Tuesday, 15 June 2010

Fritillaries

The other day I happened to be passing by Rackenford Moor in Mid Devon. It's one of the best places in the county to see Marsh Fritillaries - it's also a fantastic reserve managed by Devon Wildlife Trust - so, as they are flying right now, I just had to stop for a while.


It was a little too windy to be ideal for photography but the butterflies were easy to find, feeding and basking on Common Spotted Orchid and their larval food plant Devil's Bit Scabious.


On the drier slopes I also found a few Small Pearl-bordered Fritillaries.

Tuesday, 8 June 2010

Cantharis fusca - new for Devon?

The marshes by the River Clyst at Highfield Farm hold more than a few insect species which are extremely local in Devon and the South West. A couple of days ago I found this beetle, Cantharis fusca, which is possibly the first record for the county.


I normally photograph any beetle presenting itself this well but it was only when I looked more closely at the photo that I suspected it might not be the usual Cantharis rustica which is very common on the farm right now. In fact it differs in two obvious features: the legs are all black, not showing the red femora of rustica (see photo of rustica below), and the black mark on the pronotum (that's the squarish disc between the head and wing cases/elytra) reaches the front edge rather than being an isolated spot in the middle.

I emailed a photo to Keith Alexander - the organiser of the national recording scheme for these beetles - who confirmed my identification. According to the provisional atlas (Alexander, 2003), this is a species of 'permanently damp or wet soils, such as lowland hay meadows and marshy grassland'. As for it's distribution, it was much more widespread in the past, 'presently confined to a few southern coastal counties and parts of Yorkshire' (Alexander, 2003). Keith tells me that he has long suspected that it might be present in south east Devon but has not so far found it here himself.

I wonder if I've overlooked it in the past as the differences from rustica are not immediately obvious; a couple of days later I found another, this one with a more typical pronotal pattern.


Finally, here's the common Cantharis rustica.


Refs:

Alexander, K.N.A. 2003. Provisional atlas of the Cantharoidea and Buprestoidea (Coleoptera) of Britain and Ireland. Huntingdon: Biological Records Centre.

Saturday, 29 May 2010

A Few Beetles - a new look


I've decided to play around with the blog template - I'm not happy about the amount of blank white space on the screen. Also photos could be larger on the page without having to click through. Here are a few of the beetles I've photographed recently, starting above with a very common click beetle Athous haemorrhoidalis.


Next up is an Asparagus Beetle Crioceris asparagi, unfortunately all too common on the asparagus shoots on our allotment; still it's a beautiful beetle - just have to try to eat the asparagus before the beetles do.


This monster is a ground beetle Elaphrus cupreus; common in the marshy areas down by the River Clyst.


Another leaf beetle (as is Crioceris above), this is Galerucella sagittariae, also found in the wet fields by the Clyst, in this case feeding and egg-laying on docks.

This is a rove beetle, or 'staph' (Staphylinidae). There are about a thousand British species and most require a specimen to name with certainty, all I can say with this is that I believe it's a species of Paederus.

The next two I can be sure of. Above is a rather nice, though small, long-horn beetle Pogonocherus hispidus.


Finally a very common and conspicuous cardinal beetle Pyrochroa serraticornis.

Friday, 28 May 2010

Cuckoo and Buzzard - from Cuba and India

It's been a while since I posted any illustrations so here are a couple of  birds that I've been working on.


Great or Cuban Lizard Cuckoo Saurothera merlini from Cuba (not surprisingly) and The Bahamas; 'Lizard Cuckoo' presumably because it eats lizards. It's also one of the many cuckoos that rears it's own young. A constant problem I have illustrating many cuckoos is that the tail pattern is an important identification character but both upper and undersides need to be shown, with this species at least I can get around this by showing two subspecies - nominate merlini on the left and decolor (greyer upperparts) in the middle. The bird on the right is a juvenile, not quite finished - actually all of them could do with a bit of touching up - since I haven't yet been able to locate a juvenile specimen.


Many years ago I painted a few plates of raptors for 'Birds of the Indian Subcontinent' by Richard Grimmett and Carol and Tim Inskipp. As A&C Black/Helm are preparing a revised edition I've been asked for some new figures - no new birds, just corrections to illustrate new taxonomic decisions. This is a Himalayan Buzzard Buteo burmanicus (at the moment at least, the name may not stick). The general opinion now is that it is not a subspecies of 'Common' Buzzard B.buteo but should be split, though how it relates to East Asian buzzards B.japonicus is unclear to me at least. I actually thought I'd illustrated this form in the first place but since then many more photos have become available and I've seen a lot of eastern buzzards in China, Tibet and Xinjiang so I've made a few changes. I'm waiting for the authors' comments to see whether they agree.

My original figures were painted at one and a half times the size on the printed page, this was painted at double size. I can't work as small as I used to - I don't think it's my eyesight, I think it's because I'm painting a little more loosely generally these days.

Friday, 21 May 2010

Scorpion Flies

There are some spectacular insects lurking in our hedgerows, albeit on a small scale. Scorpion Flies are particularly exotic looking beasts; yellow and black with patterned wings and a prominent beak. Males carry their swollen ‘tail’ curved over their back very like a scorpion. Although it may look menacing there is no sting in the tail - it’s there for mating. Scorpion flies (order Mecoptera) are easy to find in hedges and woods, often sitting motionless only to disappear when a lens is focused on them. They are mostly carnivorous and seem to prefer dead to living insects, I’ve seen them feeding on tiny flies and much larger bumblebees (which surely must have been dead already - see photo below). There are officially  three species in Britain (Panorpa communis, P.germanica and P.cognata), although the unproven presence of a fourth, P.vulgaris, has been suggested (Plant, 1997).



All three species are very similar but, in the males at least, can be identified with fair certainty by examining the ‘sting’ at the end of the abdomen. The important characters are very hard to see in the field but can be checked on good close-up photos. On the lower (ventral) surface of the genital capsule (the swollen bit) is a pair of  structures known as hypovalves (photo below), these differ in shape in the three species as follows:


Panorpa germanica – hypovalves  parallel or slightly diverging, expanded at tip - as photo above.

Panorpa communis – hypovalves  slender, not expanded, curving out and then converging at tip.

Panorpa cognata – hypovalves  slender, not expanded, diverging at tip.


Because male scorpion flies helpfully hold the tip of the abdomen curved over, the ventral surface is actually the upperside as seen in the field.

After checking as many scorpion flies as I can photograph, I find that germanica is the commonest in my area of Devon, with occasional communis – even in the same hedge. I’ve yet to find cognata. P.germanica males are abundant as I write this (mid May) with females appearing in the last week or so. This female (presumably germanica) is feeding on a Bibio marci carcass.


It is rumoured that P.vulgaris may occur unnoticed in Britain, although I can't find any stated reason other than that it's common just across the channel. The shape of the hypovalves is virtually identical to those of communis, the only difference apparently being the more heavily spotted wings of vulgaris (Tillier, 2008). To describe these differences accurately I'm afraid we’re going to need some more technical terms: the next photo is a wing of P.communis.


P.communis – wings lightly spotted, basal spot small or absent, submedial band narrow and always divided into two parts, marginal spot small and narrow, pterostigmal band narrow and incomplete – never a complete ‘Y’, as photo above.

P.vulgaris – heavily spotted wings, basal spot large, submedial band large and complete, marginal spot large, pterostigmal band usually large and ‘Y’ shaped.

So I'll be looking carefully for any communis lookalike with well spotted wings.

Refs:

Plant, C.W. 1997. A Key to the Adults of British Lacewings and their Allies (Neuroptera, Megaloptera, Raphidoptera and Mecoptera). Field Studies, 9, 179-269.

Tillier, P. 2008. Contribution à l’étude des Mécoptères de France. Deuxième partie : clé de détermination des Panorpa de France (Mecoptera Panorpidae). L’Entomologiste, 64, 1, 21-30.