Ross's Gull close up at the Recreation Ground

21st July 2014 - Topsham

 

After two months of regular appearances at Bowling Green Marsh and Goosemoor and with just two brief visits to the Rec - when I wasn't there,  I finally get to add Ross's Gull to my local patch list. Better still, it fed on the near shore and the rising tide brought it to within twenty feet or so - by a long way much the closest I've yet been to it and well worth the wait.

All photos enlarge when clicked.

Ross's Gull - 21/7/2014 Topsham

Ross's Gull - 21/7/2014 Topsham

Ross's Gull - 21/7/2014 Topsham

Ross's Gull - 21/7/2014 Topsham

Ross's Gull - 21/7/2014 Topsham

Ross's Gull - 21/7/2014 Topsham

Ross's Gull - 21/7/2014 Topsham

Ross's Gull - 21/7/2014 Topsham

Ross's Gull - 21/7/2014 Topsham

It's still a fairly shabby looking bird, head feathers dropping off almost as I watched and scapulars very worn. Primary moult about halfway through - P1-4 new, P5 growing (just visible on right wing) and P6-10 brown and very worn. No sign of replacement in the secondaries or coverts yet and the tail feathers are all old.

Just got to hope it hangs around another couple of months to show a nice fresh winter plumage.

First of the season

17th July 2014 - Topsham

Small numbers of juvenile Herring and Lesser Black-backed Gulls have been regular at the Rec over the last week or so and among this year's debutantes I recently found this striking bird.

Yellow-legged Gull juv 17/7/2014 - Topsham

Yellow-legged Gull juv 17/7/2014 - Topsham

Obviously my first thought was Yellow-legged Gull, it was very different to the Herring and Lesser Black-backed juvs nearby with its whitish head and body and those whitish fringes to the scapulars and coverts. The tertials and greater coverts looked fine and it did seem to be more advanced than other juveniles, the fringes to the mantle and upper scapulars (and a few of the lowers) were quite worn, all indicating the earlier fledging michahellis. Then I looked at it some more and, as usual, tried to talk myself out of it. The bill was not large and sometimes looked rather weak and graellsii-like. The flanks were quite heavily-marked and the legs very dark on the shins - mud perhaps?

Yellow-legged Gull juv 17/7/2014 - Topsham

Yellow-legged Gull juv 17/7/2014 - Topsham

Yellow-legged Gull juv 17/7/2014 - Topsham

Yellow-legged Gull juv 17/7/2014 - Topsham

It took flight eventually revealing, as I expected, dark inner primaries - though slightly paler than the outers - and a largely white rump and upper tail coverts contrasting with a black tail band. The tail band is somewhat broader than is typical of michahellis but, as far as can be seen from this distance and angle, the outer tail feathers seem quite white at the base.

Maybe not a classic michahellis but the only other option is a very pale Lesser Black-backed, or am I being over cautious? All comments welcome as usual.

Dune Robberflies

12th July 2014 - Merthyr Mawr, Glamorgan

A weekend visit South Wales meant a few hours available to spend searching the dunes at Merthyr Mawr for some charismatic microfauna. I was hoping for Dune Tiger Beetle Cicindela maritima but drew a blank, fortunately Dune Robberflies Philonicus albiceps were everywhere I looked and provided a nice exercise for my rusty macro technique.

All photos taken with 180mm macro lens, f/8 at 1/160 -1/500 sec hand held. Species checked using the keys Stubbs and Drake (2001). 

Philonicus albiceps 12/7/2014 Merthyr Mawr

  P.albiceps is found on sand dunes all round the coasts of England and Wales, it is often common and can be abundant. Adults are found from mid May until mid October with numbers peaking in June and July (Stubbs and Drake, 2001). The larger robberflies (family Asilidae) are usually fairly obvious as such, with eyes separated by a 'dip' ('vertex' to be technical), bristly moustache and stout stabbing mouth-parts. They're all active hunters of insects and this one specialises in catching other flies as shown by this female below (prey species unknown).

Philonicus albiceps 12/7/2014 Merthyr Mawr

 P.albiceps is more than capable of tackling larger flies such this Empid (probably Empis tesselata) below.

Philonicus albiceps 12/7/2014 Merthyr Mawr

 The bigger the prey, the bigger the meal; I found a male (the shape of the tip of the abdomen is the clue in this family) sat on a rusty oil drum sucking the juices out of this Muscid (a Coenosia sp.?).

Philonicus albiceps 12/7/2014 Merthyr Mawr

 The proboscis is clearly visible piercing the prey's thorax; and while the mouth-parts are strong enough to hold the prey without using the legs, It helps that robberflies inject a venom that seems to kill their prey immediately.

Philonicus albiceps 12/7/2014 Merthyr Mawr

Reference

Stubbs, A.; Drake, M. (2001) British Soldierflies and their allies. BENHS

Horseflies - my insect nemesis

I've never been a fan of horror films but I think I can understand the attraction; I get what I guess is a similar tingle of fear whenever I see a horsefly close up. I'm one of those who react badly to horsefly bites, typically it swells up like an egg and I suffer several days of intolerable itching (as I write I've got an unsightly red 'wound' on my arm after a bite six days ago). I have to admit though that they do have a kind of macabre beauty, I mean, just look at the eyes on this one.

A deer fly Chrysops viduatus 21/7/2005 Topsham

As in many families of flies, the sex can be told from the eyes - meeting on top of the head = male, separated (as here) = female. It pays to know this since only females bite (males prefer nectar) and the offensive hardware, the proboscis, is clearly visible under those green and purple eyes.

A word on Common/English names: given their predatory habits, biting flies tend to get noticed and a few of these have acquired common names. Since folk taxonomy rarely discriminates beyond the genus specific names have been invented in an attempt to make them 'more accessible'. In my opinion if you're interested enough to specifically identify this 'Square-spot Deerfly', you aren't going to be put off by it's scientific name - Chrysops viduatus Tabanidae.

This is one of about 30 spp. of horsefly (Tabanidae) found in Britain and this family contains the worst biters in my opinion - apart from mozzies of course, but that's an entirely different subject. They're often big, they're ugly (or are they beautiful, I can't decide) and their bites can itch like hell - I'd rather be stung by a wasp than bitten by a cleg (see below).  Deerflies may prefer deer but I've been bitten a few times - they usually go for the head and neck. Unlike these next two which tend to go for the arms or the back of the legs.

A cleg Haematopota pluvialis 9/7/2006 Topsham

Eyes not meeting on top so a biting female - be afraid.

A cleg Haematopota crassicornis 22/7/2009 Dunsdon

Eyes meeting on top so a non-biting male - relax, it's harmless.

Haematopota spp. (literally 'blood drinker') also go by the name of 'cleg' (always enjoyed the name - seems so apt for these quite unpleasant little beasts - and I make no political comment here). These are tough critters and can survive a fairly hard swat with the hand, after a few seconds they just pick themselves up and fly off - or more likely come back for another go at the back of your knee.

Clegs and deerflies are fairly modest sized flies - about the same as a housefly - but there are some alarmingly larger species out there. The larger 'horseflies' proper are nowadays divided between two genera, Tabanus and Hybomitra; There are about 17 spp. but many are rare and only half of them bite - the females, that is. Tabanus bromius (below) is actually one of the smaller examples but still about wasp-sized.

Tabanus bromius 27/6/2009 Salcombe Regis

 Eyes not meeting - a biting female - run away.

Next is a fairly large one, T.autumnalis. You'll notice I say 'fairly large', there are 'giant' horseflies out there - T.sudeticus should occur around these parts (though I've never noticed it) and can be an inch long, or about the size of a Small Elephant Hawk-moth!

Tabanus autumnalis 13/7/2005 Topsham

Eyes not meeting - a biting female.

The very similar genus Hybomitra differs most obviously in their hairy eyes - though you have to get uncomfortably close to see this. Here's H.distinguendua, a fairly large species.

Hybomitra distinguenda 22/7/2005 Topsham

Eyes separated - I think you know what that means.

I've never knowingly been bitten by one of these larger flies and I think I'd have noticed, in fact I'd probably need hospital treatment. I suspect they prefer to bite cattle or horses, humans just aren't worth the effort.

All species photographed and identified by me (in some cases verified by the good folks at diptera.info) using the keys in the excellent Stubbs and Drake (2001).

Reference

Stubbs, A.; Drake, M. (2001) British Soldierflies and their allies. BENHS

Blue-tailed Damselfly - a new one for the garden

3rd July 2014 - Topsham

Found this is the front garden this afternoon - I was actually listening for Wood-crickets (more later) - I popped back in for my camera and macro lens, eventually refound it and took some photos; no time to set up tripod, hand held 1/160 to 1/250 sec at f/8. It's always a job to get all the thing in focus at such close range, so quite pleased with result.

Blue-tailed Damselfly Ischnura elegans 3/7/2014 Topsham

Blue-tailed Damselfly Ischnura elegans 3/7/2014 Topsham

 This is a common species and I've photographed it a few times in the area, surprisingly never recorded it in the garden before. Females (like this one) come in several varieties, this rather nice specimen is the form 'rufescens'.

Southbound - Common Sandpiper

2nd July 2014 - Topsham

Most people think autumn starts in September but for birds - and birders - the signal is the first returning waders, often as early as late June. By July things are really kicking off; this morning Common Sandpipers were in evidence at the Rec, at least three and perhaps as many as five.

Common Sandpiper - 2/7/2014 Topsham

Common Sandpiper - 2/7/2014 Topsham

Common Sandpiper - 2/7/2014 Topsham

'Caspian' Gull revisited

22nd June 2014 - Topsham

As I'd hoped, our mystery gull turned up again, this time under rather more favourable viewing conditions at Topsham Rec. The same slightly odd shape and the same wing pattern as the BGM bird of Friday, and no real surprise, it's a Herring Gull.

Herring Gull 2nd Summer/3cy 22/6/2014 - Topsham

Herring Gull 2nd Summer/3cy 22/6/2014 - Topsham

Herring Gull 2nd Summer/3cy 22/6/2014 - Topsham

The bill is quite hefty and with a strong gonys. The primary projection is standard Herring Gull length and the legs don't look that thin after all. The breast is an odd shape for Herring but this may be due to a full crop, or perhaps it's eaten something it shouldn't have. The mantle is definitely too pale for cachinnans and there are a few remaining 2nd winter/3rd generation scapulars showing a Herring type anchor mark pattern. The median coverts are fresh (still with buff-brown ground colour) so, if I've interpreted its age correctly, must be recently grown 3rd generation. They do have the appearance though of 2nd generation feathers (which are more usually plain grey at this stage) but this may be down to the health/hormonal condition of the bird? The iris, although rather darker than usual for this age argenteus, is starting to lighten.

Apart from a slightly odd shape (still not right for Caspian though) and unusual median coverts it probably wouldn't draw a second glance if seen well. I can't quite believe how much time I've spent on it, I suppose once it was claimed as a Caspian (still don't know who by) I really wanted to figure out: is it? and if not, why not? It's all educational, after all.

Thanks to Matt Knott and Gavin Haig for their comments on Friday's appearance.