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The toughest day of 2010: Phratora polaris

24th June 2010: day three of my Scottish fieldwork campaign was to be a change from surveying for saproxylic beetles in woodland. I was headed to the summit plateau of Ruadh-stac Mòr, Beinn Eighe where Mike Morris (1970) discovered the leaf-beetle Phratora polaris new to Britain in 1966. Ruadh-stac Mòr lies within the massive (5,800 hectares) Torridon Forest SSSI.

male Phratora polaris

I had picked a day with a dry forecast but normal weather forecasts don’t apply in the mountains. I set off walking at 07.35 and it started raining 10 minutes later. Within another 40 minutes, I was out of mobile signal for the rest of the day. After a couple of hours of slog, I entered the fearsome Coire Mhic Fhearchair and picked my way across to the steep scree fan in the far corner, passing a few mangled bits of plane wreckage where some poor aviator met his doom. The scree was treacherous underfoot and I was ascending into cloud, with worsening rain and an increasingly strong wind. At the top of the scree, the route steepens into a narrow chute of shattered rocks, exposed and channelling a wicked gusting wind. No place to miss your footing. Step by careful step I got to the top. But there was no relief there – I found myself on a knife-edge ridge in ferocious gusting wind and driving rain. On hands and knees I found a cleft in a boulder and wedged myself half in. Put some dry layers on and decided I’d better abandon the survey and descend. But actually couldn’t face the chute again straight away so I decided to stroll up towards the summit plateau for a bit of respite before beginning my descent. Conditions had worsened further and I was soon reduced to lying full-stretch on the ridge-top path, clinging to the ground and holding my rain-spattered specs on to my face. I realised the ridge had broadened out and I could safely drop off the path to the leeward side, where I could get about in a crouch rather than a crawl.

The chute.

I soon realised I was treading on quality turf: dolomitic limestone grassland with Racomitrium moss, Sibbaldia Sibbaldia procumbens, Dwarf Cudweed Gnaphalium supinum and, more importantly, some patches of Dwarf Willow Salix herbacea, the foodplant of Phratora polaris. I found fragments of a dead Phratora polaris under the first stone I lifted, and a live one under the third stone. Flushed with success I carried out a standard 30-minute timed search but didn’t see any more of the leaf-beetles. All I saw were three Oreostiba tibialis (Staphylinidae), a common species of montane habitats, and one Patrobus septentrionis (Carabidae), found feeding on a pill-beetle Byrrhus fasciatus (Byrrhidae).

Habitat of Phratora polaris.

Phratora polaris was added to the British list (under the former generic name Phyllodecta) by Morris (1970) on the basis of specimens he found near the summit of Ruadh-stac Mòr, Beinn Eighe in 1966 and 1967. Morris (1970) also reported a specimen collected by A.M. Easton near the summit of Tom a’ Chòinich, Inverness-shire in 1968. Owen (1983) added two further sites in 1981: Sgurr Mor and An Teallach, both Wester Ross. Lyszkowski (1988) found the species in 1984 some 60 miles to the south of these sites near the summit of Beinn Achaladair, Argyllshire. Cox (2007) was able to map the species from 9 Scottish 10-km squares of the national grid and commented that the species is “probably under-recorded”. Quite frankly, it’s no wonder!

Once I’d made it down to the bottom of the scree, I found some shelter from the dreadful weather and took a break. Astonishingly, a Mountain Bumblebee Bombus monticola flew past my nook as though it were just a normal summer’s day. I was also filled with respect for the elderly Munro-bagger I passed on my way down – he was heading up in shorts!

Acknowledgement

These observations were made during SSSI condition monitoring work for Scottish Natural Heritage.

References

Cox, M.L. (2007). Atlas of the seed and leaf beetles of Britain and Ireland (Coleoptera: Bruchidae, Chrysomelidae, Megalopodidae and Orsodacnidae). Pisces, Newbury.

Lyszkowski, R.M. (1988). Phyllodecta polaris Schneider (Col., Chrysomelidae) in Argyllshire. Entomologist’s monthly magazine, 124, 71.

Morris, M.G. (1970). Phyllodecta polaris Schneider (Col., Chrysomelidae) new to the British Isles from Wester Ross and Inverness-shire, Scotland. Entomologist’s monthly magazine, 106, 48 – 53.

Owen, J.A. (1983). More about Phyllodecta polaris Schneider (Col., Chrysomelidae) in Britain. Entomologist’s monthly magazine, 119, 191.

Owen, J.A. (1988). A note on the life history of Phyllodecta polaris Schneider (Col.: Chrysomelidae). Entomologist’s record and journal of variation, 100, 91 – 92.

 

When the hunter becomes the hunted

On 21st June 2010 I drove for 10 hours from home to get to Ullapool; the start of an 11-day entomological survey campaign in the west of Scotland. My survey site on 22nd was Rhidorroch Woods SSSI which turned out to be a couple of hours drive on dirt tracks up an increasingly beautiful glen. The weather was superb – a rare treat in NW Scotland – and I couldn’t wait to get into the field.

Rhidorroch Woods SSSI

This isolated veteran pine, above the modern-day treeline, was the best tree I found. Scarred by lightning strikes and ripped by the weight of winter snow, but still living, it was a magnet for saproxylic beetles.

On a fine, sunny day in Scotland, when big beetles like clicks, chafers and longhorns are buzzing past on the wing, there is no better place to be. As long as you’ve got a midge net (and are prepared to abandon all personal dignity and actually wear it)!

Undignified headgear

You also need to keep one hand free for swatting horseflies. And a little time is required each evening for tweezering off all the ticks!

It pretty much goes without saying, but the warning colours of this Bee Beetle Trichius fasciatus (a chafer) failed to frighten me. Very few of these Batesian mimics seem to be good enough at mimicry to fool the human eye.

Bee Beetle Trichius fasciatus

But, as I was investigating the hollow interior of a decaying birch, a bumblebee started harassing me at close quarters. I immediately backed off and legged it away for about 20 metres, reckoning I must have disturbed a nest. As soon as I stopped, I realised it was still buzzing round within a few inches of me. I carry an adrenaline injector with me at all times in case of bee stings: I’ve had a couple of bad allergic reactions in the past. But, even so, getting stung in such a remote spot could be difficult. I legged it back to the birch tree to grab my net, still with the bumblebee in pursuit, and netted it. Safe. Phew!!!

It was only then that I realised it wasn’t a bumblebee! The size, shape, flight and especially the buzzing tone were all spot on and had me completely fooled. But this was a fly, and like nothing I’d seen before. Much later, with help from Dave Gibbs and Andy Grayson I was able to identify it as Cephenemyia auribarbis.

Cephenemyia auribarbis

Cephenemyia auribarbis is a bot-fly (family Oestridae) and it was not looking to bite me or sting me but to lay eggs on me, so that its larvae could develop in either my nostrils, mouth or throat: a truly horrifying prospect! It should have been chasing after Red Deer, the usual host.

Acknowledgement

These observations were made during SSSI condition monitoring work for Scottish Natural Heritage.
 

Christmas shopping entomology

I know for most people a Christmas shopping trip is a lost natural history opportunity. But for a pan-species lister, something good can turn up wherever and whenever. First up, this striking black-and-red Arocatus ?longiceps? bug found on the trunk of a Plane tree while browsing the Christmas market on the Champs Élysées, Paris on 20th November. My French specimen (on the left) looks quite different to the Arocatus longiceps I have previously found on London’s Plane trees (on the right, from the Natural History Museum’s wildlife garden), with paler appendages and reduced black markings on the body.

Arocatus from the Champs Elysees (L) and NHM garden (R)

The following weekend we visited Whipsnade Zoo with friends Rich and Sara and budding mammalogist Lucy. As well as doing some Christmas shopping in the gift shop, we found a couple of interesting insects in the Insect House but on the loose. There were trails of a miniscule ant which I think is a species of dolichoderine but doesn’t seem to be included in Bolton & Collingwood’s RES Handbook, or Skinner & Allen’s Naturalists’ Handbook.

Miniscule ?dolichoderine? ant from Whipsnade

And on the exit door, this Australian Cockroach Periplaneta australasiae was making a bid for freedom. I’ve seen this species before in the Eden Project biomes.

Australian Cockroach Periplaneta australasiae

Finally, our local Tesco in Leighton Buzzard still supports a population of the weevil Otiorhynchus crataegi in the car park, first found here in September 2008. To the best of my knowledge, this is the only Bedfordshire site for this weevil but I’m sure if more people looked it could be found much more widely. It was discovered new to Britain in Berkshire in 1980 and has since been reported from Surrey and Middlesex (map here, doubtless incomplete).

Every little helps (the beetle list)

Entomologising in car park shrubberies can be pretty good. Look out for feeding signs such as notched leaves. Whenever I get out my beating tray and start thwacking the shrubberies, I always imagine I’m going to be either set upon by security guards or ridiculed by crowds of jeering shoppers. But, in practice, everyone studiously ignores me, though I sometimes think mothers take a tighter grip of their children’s hands as they pass! Richard ‘Bugman’ Jones would advise wearing a hi-vis vest in such circumstances: it makes you look so much more official!

Notched leaves on this Euonymus are the first sign that weevils are present.

Otiorhynchus crataegi makes quite regular, semi-circular notches in the edges of the leaves.

Otiorhynchus crataegi: at a supermarket near you?

Happy Christmas shopping everyone!

 

Devil’s-bit Scabious Jewel Beetle Trachys subglaber

March 2016 update: Since writing this post in December 2011, it has become clear that “Trachys troglodytes” actually consisted of two species: Trachys subglaber and the true Trachys troglodytes. This post and the photo above refer to Trachys subglaber. For more info on Trachys, see the jewel beetle page.

While Trachys subglaber may not be quite as jewel-like as some of its larger relatives in family Buprestidae, it is still a little gem. I’ve only started finding it in the last couple of years while surveying calcareous grasslands with a suction-sampler.

Devil’s-bit Scabious Jewel Beetle Trachys subglaber

The best way to record this species, as Keith Alexander has described (Alexander, 1989), is to look for the larval leaf-mines in the host plant: Devil’s-bit Scabious Succisa pratensis. Late summer into early autumn is a good season to be looking, when the Devil’s-bit is in flower. But if you are confident at recognising Devil’s-bit from just the leaves, the leaf-mines can be found from at least 7th June (my earliest record).

Trachys troglodytes mine

Trachys subglaber is not the only species to mine the leaves of Devil’s-bit but the shiny black spot is diagnostic; it marks the spot at which the egg was laid and thus marks the point from which the larva starts feeding to produce its full-depth blotch mine.

Until Keith sussed out the leaf-mines and published his note, Trachys subglaber was regarded as quite a rarity. The current map shows it is widespread in southern Britain, though not nearly as widespread as the distribution of its host-plant! [16.iii.2016: note that I have linked to the map of Trachys troglodytes on the NBN, but this is an error on the NBN – most of these are records or either troglodytes or subglaber and most should be reassigned to T. subglaber]

Reference

Alexander, K.N.A. (1989). Trachys troglodytes Gyllenhal (Coleoptera: Buprestidae) widespread in the Cotswold limestone grasslands of Gloucestershire. British journal of entomology and natural history, 2: 91 – 92. [Browse this article online here].

Pan-species listing milestones

Jonty Denton’s still not letting up, with 289 species added since mid-May taking his record-breaking list through 10,500 to stand at 10,535.

Dave Gibbs isn’t ready to submit an update yet but has added about 250 species during 2011 and reckons he’ll get to 10,000 by about the end of 2012.

Graeme Lyons and Martin Harvey have both broken 3,500 during the year. Graeme retains a slender lead.

Jon Newman, Steve Gale and Sarah Patton have all had very good years and all broken through 3,000 during the autumn. Sarah has pulled well clear though, by finishing the job of gleaning records from old notebooks to take her list to 3,327. Jon and Steve are neck-and-neck on 3,013 and 3,012 respectively!

Seth Gibson has just passed his target of 2,500 and has his sights set on 3,000.

Mark Skevington will be passing 2,000 before much longer.

Most of the pan-species listers have been spurred into tackling new groups, and fungi especially have been a rich source of new species, along with mosses, liverworts and beetles. Despite this fine example set by others, I seem to have spent most of the year concentrating more and more on beetles. Despite the fact that I’ve only seen a little over half the British and Irish beetle fauna and there’s still almost 2,000 species to go, it does seem to be getting harder and harder to find new ones – and more and more rewarding each time I do!

Pat-a-cake, pat-a-cake, beetling man …

This is Peter Hammond at Langley Park demonstrating his Pat-a-Cake method with fine sievings from red-rotten heartwood.

Here’s a technique for finding the sort of tiny beetles that are so small or well camouflaged that you can’t see them until they move. Try it next summer:

  1. Tip the sievings onto a sheet in full sun, preferably on a hot surface such as sun-baked tarmac.
  2. Pat the sievings down into a very thin layer.
  3. Lay aside your pipe.
  4. Take up your pooter.
  5. Get comfy.
  6. Wait for rare beetles to break cover as the heat starts to bother them.

We were looking for the tiny pselaphine Plectophloeus nitidus, which we didn’t find. But we did see the very distinctive larvae of Scraptia (Scraptiidae) with their bulbous tails that they autotomise (self-amputate) under duress.

Scilly 2011: still there!

Gareth Richards had four days off in half-term and we decided to revisit Scilly. Flew on the Skybus from Land’s End aerodrome at 10.40 on Monday 24th, found a B&B in Hugh Town, dumped our bags and set off to Lower Moors to try for the Northern Waterthrush which has been present since 16th September. But that plan was soon abandoned when we passed a couple of birders looking intently into a tiny bulb field behind Porth Mellon. “Got anything?” “We’ve seen a bird we can’t identify.” In other words, it could be mega. After about 20 minutes it showed again, very briefly in the shadows of the back hedge. Thrush Nightingale maybe? But as the crowd swelled there was talk of Veery, Hermit Thrush and even Rufous-tailed Robin. Over the next couple of hours, more and more people squeezed into the narrow viewing space, pressing me deeper and deeper into the hedge. Gareth and I both eventually saw it reasonably well and called it as a Common Nightingale. Only my second on Scilly but we’d all been hoping for something rarer, perhaps hoping too hard.

The Northern Waterthrush was to prove a devious adversary but the Wilson’s Snipe that has eluded some this autumn could not have been more accommodating. On constant show with about 6 Common Snipe, it had a preen, showing off its diagnostic underwings and outer tail-feathers before flying towards the hide and walking up the bank to feed just a few feet from me, in company with a Common Snipe for convenient comparison.

Common (L) and Wilson's (R) Snipe

Wilson's Snipe

We did see the Waterthrush in the afternoon from the Shooter’s Pool screen, calling and showing for just a few seconds. Tickable but not very satisfactory and so we hung about till dark hoping in vain for a better view. The tedium of waiting was relieved by a vocal Yellow-browed Warbler and by a brief view and a few ‘tacks’ from a Dusky Warbler just after it was found by Spider.

We spent the first and last hours of Tuesday waiting in vain at Shooter’s Pool for more views of the Waterthrush. In the middle of the day, we birded our way up to Borough Farm for superb views of the Upland Sandpiper. With that UTB, we were free to just bird and try to find some rarities of our own. Just a few fields away, Gareth found a Woodcock feeding out in the open in a bare field on Watermill Lane and we both had our best ever views of this species.

Woodcock at Watermill

On the coast path at the end of Green Lane, I picked up a dragonfly that fluttered weakly at my feet as I walked past: male Red-veined Darter Sympetrum fonscolombii! Further up Green Lane, a small crowd was watching a Hawfinch making a right mess of eating haws.

Male Red-veined Darter. A fully mature individual should have more extensive red on the abdomen.

Neither of us could face another dawn at Shooter’s Pool so we were birding Porthcressa Beach when we heard that the Waterthrush was showing on Higgo’s Pool. We missed it by three minutes, gave it another 40 and then just as Gareth gave up and set off … ‘zik!’ and there it was! It made up for its previously elusive behaviour by giving us (me, Gareth and Tony Davison) absolutely stonking views just a few metres away. After 20 minutes or so, it flew off and we punched the air! YES!!!

The Northern Waterthrush. I've always been a sucker for a zonking great supercilium.

We had the rest of the day to head out and find rarities, splitting up to cover different parts of the north of St Mary’s. In the first 24 hours of our stay on Scilly, other people had found 2 Olive-backed Pipits, Little Bunting, 2 Dusky Warblers, Pallas’s Warbler, Radde’s Warbler and White-rumped Sandpiper. Unfortunately Wednesday was a quiet day (the best find of the day was a Bluethroat on St Agnes) and we found little of note. But birding on Scilly, even without seeing anything rare, is a pleasure. And I did end the day with some excitement after a passing birder tipped me off that the Treecreeper was showing again in Carreg Dhu garden – I ran for it! My third Scilly tick of the trip (with Waterthrush and Dusky Warbler).

Thursday. Dawn on Peninnis Head with a few migrants on the move overhead including a Redpoll and a Lapland Bunting amongst others. Bizarrely, as I’ve noticed before, the vismig on Scilly seems to be of birds coming in from the west and heading back east. Perhaps at first light they realise that they’ve gone off course and turn back towards land? A fleeting view of a bird flitting out of a weedy field got both of us excited. It was ultra-wary and after chasing it through several fields it gave itself up – as just a Skylark. Faulty rare-dar!

Yesterday’s Bufflehead was still present at Housel Bay on the Lizard and we reckoned our 16.35 flight back to Land’s End would give us at least half an hour of daylight on the bird. In fact, everything went really smoothly and we spent over an hour watching the Bufflehead on a tiny pool. Perhaps the best candidate for a genuine transatlantic vagrant Bufflehead that we’ve had in Britain?

Bufflehead. It was gone by the following morning.

UTB = Under The Belt

Scilly 1985: I was there!

26 years ago, half-term, Saturday 19th October 1985, I got off the ferry on my first visit to the Isles of Scilly, aged 16, with three school-friends. We walked straight up to the Garrison camp site. While I was pitching our tent and Gareth Richards was checking in and paying, a birder with a resplendent beard walked up to me and asked “Can I interest you in a Booted Warbler?”. He’d just found it and within a minute I was onto it – the first tick of the trip! Gareth never did see it but we couldn’t give it long as we had bigger fish to fry that day. First stop was a Yellow-billed Cuckoo giving awesome views from the Garrison Walls looking down into a Sallyport garden where it was perched on a rotary washing-line! Then to the Incinerator to watch a male Rose-breasted Grosbeak scoffing blackberries. Moving quickly on to Old Town churchyard for UTV of a Red-eyed Vireo in the high elm canopy. Across the road to the school for fabulous views of a Myrtle Warbler (as it was then; Yellow-rumped Warbler now) creeping around on lichen-covered elm boughs. Up to the airport for an unbelievably showy Bobolink crawling around in the grass at point blank range. Final rarity of the day was a juv Night Heron roosting in sallows on Lower Moors. But I had one more tick to come – Brambling!

My first 'scope: an Opticron Piccolo, purchased after 6 months on a paper round.

On Sunday we took the boat to Tresco for another deluge of ticks: a Radde’s Warbler in the Great Pool sallows which is still the best one I’ve ever seen; Spotted Sandpiper, Ring-necked Duck and Richard’s Pipit all at the Simpson’s Field end of Great Pool, and then a Woodchat Shrike in some big pines and a stunning Bee-eater at Borough Farm (later to become my favourite place on Scilly!). Back on St. Mary’s I saw my first Jack Snipe and Lapland Bunting, got better, but still untickable, views of the REV and then yomped to Newford Duck Pond for a Pallas’s Warbler in failing light, my 9th tick of the day!

We had gone for quantity over quality on Sunday by going to Tresco, hoping the best of the lot would stick on St. Agnes for another day. And it did … we yomped straight from the quay to see a male Parula Warbler showing beautifully in a couple of apple trees two fields up from the chapel. To this day, one of the best birds I have ever seen in my life. An American Wigeon on Big Pool was yet another new yank for me. And back on St. Mary’s we re-located a Wryneck on Peninnis Head – another stunning new bird.

We had a day to catch our breath on 22nd and then a male Sardinian Warbler turned up at Higher Moors. It gave us a long wait but in the meantime we were there when Chris Heard called an Olivaceous Warbler at Lunnon Farm on 23rd. We eventually saw the Sard well on 24th and had time to cross over to Bryher for a Rose-coloured Starling. Attempts to see the bird were abandoned after a hostile islander dispersed the twitchers by firing his shotgun. To this day, landing on Bryher gives me a feeling of trepidation. We sailed back to the mainland the following day, leaning on the Scillonian’s railings chatting to the late, great Peter Grant about bird ID. The cost of the entire trip including tubes, trains, ferries, camping, inter-island boats and a week’s worth of Kavorna pasties was £80. I’ve been back to the magic isles many times since but 1985 can never be bettered – I’m so glad I was there!

5th British site for Dactylosternum abdominale: the back garden

Tony Allen discovered this hydrophilid beetle new to Britain from a silage clamp at Wimborne St. Giles, Dorset in 2003. It didn’t persist in Dorset but next turned up in Colin Welch’s plastic compost bins in his garden at Hemington, Northamptonshire on 2nd October 2005 where it persisted for several years but hasn’t been seen since Colin used his compost in 2010.

Tony had kindly given me one of his specimens so I knew what it looked like and had hoped I might find it in our compost bins one day. So when I lifted the lid on Wednesday 12th October and saw the back end of a hydrophilid heading down into the goo, I had no hesitation in thrusting my hand in to catch it! And Dactylosternum abdominale it was! I soon learnt of two other recent records. Martin Collier and Andrew Duff found it in a rotten hollow poplar log in a plantation near Mundford, West Norfolk, on 29th September, and James McGill found half a dozen on a well-rotted bracket fungus in Swell Wood, South Somerset on 2nd October. It sounds like it is getting established this year, especially as it is being found in more natural microhabitats. I have since found more in my compost bin.

Hawthorn Jewel Beetle Agrilus sinuatus

Hawthorn Jewel Beetle. One of Philip Harwood's specimens photographed at Oxford University Museum of Natural History.

I have never actually seen a live Hawthorn Jewel Beetle Agrilus sinuatus though I have recorded the species on a dozen occasions. It can be found over a wide area of southern England (map here) by looking at mature hawthorns where the D-shaped exit-holes are a tell-tale sign. The D-shape matches the cross-section of the adult jewel beetle: flattened on top and convex below. The holes are best looked for on lower branches that are dying back but can also be found on the trunk and major boughs.

D-shaped exit hole characteristic of Agrilus.

To be extra sure you have found Agrilus sinuatus exit-holes, you can whittle away the bark to reveal the vacated larval borings which seem to always have quite a regular snaky, zig-zag pattern. The larval borings are also illustrated in a note by Keith Alexander (1990) who pioneered the recording of jewel beetles in this way: available online here. I would like to think that the ‘sinuatus’ of the name (given by Olivier in 1790) refers to the sinuate pattern of the larval borings.

Snaky borings of Agrilus sinuatus in a hawthorn branch.

Finding adults in the field must require some luck. They may be very short-lived, they may spend their lives out of reach around the crowns of hawthorns, or they may be too flighty to simply tap them out onto a beating tray. Agrilus sinuatus was regarded as ‘very rare’ by Fowler in 1890, as Vulnerable (RDB2) in 1987, and was downgraded to Nationally Scarce (Na) in 1992 and although still officially Na today we can probably safely call it common, largely thanks to a better understanding of how to spot the signs.

The best way to see adults would presumably be to rear them out of a suitable hawthorn branch. Under natural conditions, adults are active from mid-June to late September so collecting a branch any time up to mid-June ought to do it. The trick would be to find a branch that doesn’t yet have any D-shaped holes in it but looks like it will do soon!

Reference

Alexander, K.N.A. (1990). Agrilus sinuatus (Olivier) (Coleoptera: Buprestidae) widespread in Gloucestershire, and at a Herefordshire locality. British journal of entomology and natural history, 3: 31 – 32. [Browse this article online here].