Category Archives: Surveys

Nice weather for water beetles — not

One of the delights of entomology is that you can always find insects — any place, any time of day, any time of year. They are so many and so diverse that you can find them everywhere. On Monday 20 June 2016 my thesis, however, was about to be sorely tested. At the height of the British summer (quite literally, since this was the day of the summer solstice this year), it was tanking down. And insects really don’t like the rain.

When I started the ‘Curious Entomologist‘ workshops my title was partly inspired by Simon Barnes’s book How to be a bad birdwatcher. His credo was similarly based on the notion that if you look out of the kitchen window on a winter’s day you will see no mammals, reptiles or amphibians — but you will see birds. You can always find birds; and you can always find pleasure in them. This is even more true of insects. You might have to look a bit harder, a little closer perhaps, but they are always there, and they can always be found.

This, then, was to be my pompously grand claim when offering a two-day class to some London Wildlife trainees; “Let’s go and find some insects” I said, as we peered through the rain splattered classroom windows, off into the sodden undergrowth of Devonshire Road Nature Reserve. No-one seemed very enthusiastic. Nevertheless, we trudged off into the deluge.

I hate to tell you, but you're holding that beating tray upside down.

I hate to tell you, but you’re holding that beating tray upside down.

We caught one butterfly; sort of.

We caught one butterfly; sort of.

The plan behind the workshop was to introduce the environmental management trainees to some of the basics of entomology — how to use nets, beating trays, collecting tubes, hand lenses and microscope. How to find insects, if necessary how to deal with sample specimens collected for identification, and how to mount, label and store them for later examination, or for forwarding to someone else to look at. We were struggling at the ‘find’ stage, though.

Previous LWT events at the reserve were alive with insects — butterflies and bees flying past our ears, and the sweep nets thronging with small fry to look at back in the make-shift laboratory. Today I was going to be happy finding a few watery woodlice and some damp springtails. If this were an environmental survey, I’d have taken one look out of the kitchen window and immediately rescheduled. Insects really, really, do not like rain — even water beetles. Entomologists aren’t that fond of it either really.

Back in the classroom I was given the butterfly bucket of tea to try and revive me.

Back in the classroom I was given the butterfly bucket of tea to try and revive me.

Despite our meagre findings, microscope work is still very rewarding — everything, but everything is revealed as a miniature marvel of colour or form.

Despite our meagre findings, microscope work is still very rewarding — everything, but everything is revealed as a miniature marvel of colour or form.

We’d found a few waterlogged grass bugs, a couple of speckled bush-cricket nymphs, bedraggled dung flies, some centipedes, and those woodlice. OK that was enough to be getting on with I suppose, and there was a fair bit of interest as we examined them under the stereoscopes. Then there was this.

Gymnosoma rotundatum, nationally rare (red data book) shield-bug parasitoid.

Gymnosoma rotundatum, nationally rare (red data book) shield-bug parasitoid.

This scarce southern fly had occurred on the site before (2007), but to have one turn up in the net of the proverbial tyro was a gift. It proved there was an ongoing colony here, in what is one of its most northerly and most urban localities. This is exactly the thing to demonstrate how beginners can find unusual and scarce things, but that they are usually small, need to be collected and need to be preserved so that an expert can spot them. A very positive end to the day.

Thankfully day two was brighter and, more importantly, drier. Now we could get stuck in.

Two more unusual finds confirmed that you do not need the accustomed eye of the hardened bugman to find scarce insects:

Female of Eucera longicornis. A more obviously long-horned male turned up further down the railway line, at Hither Green, in 2008. Good to know there are established colonies in this area.

Female of Eucera longicornis. A more obviously long-horned male turned up further down the railway line, at Hither Green, in 2008. Good to know there are established colonies in this area.

A tiny weevil, Acalles misellus; not necessarily scarce, but secretive, and new to me. A 'dead hedge' species, declining in an age when dead hedges are

A tiny weevil, Acalles misellus; not necessarily scarce, but secretive, and new to me. A ‘dead hedge’ species, declining in an era when dead hedges are no longer a common boundary construction.

So we ended on a high — the trainees enthused that unusual and weird bugs loitered in every hedge bottom and me that we could, after all, find insects no matter the weather.

Advertisements

Not a powerpoint presentation in sight

Last Friday saw me at London Wildlife Trust’s newest reserve at Woodberry Wetlands, off the Seven Sisters Road in North London, giving a workshop grandly entitled: Identifying butterflies, moths and invertebrates. So just all insects then.

Like other conservation organizations, London Wildlife Trust can get great exposure, and some extra funding, by offering events like this to a fee-paying public. But just how to pitch the vast and complex world of entomology to 10 strangers with little or no expert knowledge of the natural world? My dilemma was compounded by the fact that I’d be getting there by public transport, travelling through central London in the rush hour, and trekking from Manor House Tube on foot.

Actually, that more or less sorted it — travel light. So in the spirit of less is more I was able to follow my usual path of avoiding powerpoint presentations and concentrated on waving my arms about, then waving a net.

There was arm and net waving from the very beginning.

There was arm and net waving from the very beginning.

One of the delights of entomology is that anyone can study insects with a minimum of equipment, and with immediate success. We were armed with rudimentary sweep nets and beating trays and an assortment of plastic tubes and bottles. As usual, it was all very Heath-Robinson.

Just look at the childish glee on that face, and yet I've seen it all before.

Just look at the childish glee on that face, and yet I’m the one who’s seen it all before.

This, then, was my message, delivered with a smirk and an exuberant shirt: the only equipment you need is your eyes. We went off with no expectations and no prior knowledge of the site to see what would turn up, and to try and fit that into how insects are classified, how we might tell them apart, and how even a beginner can contribute through the multifarious tendrils of citizen science.

Woodberry being a lake, almost the first insect we found was the water ladybird, Anisoticta novemdecimpunctata, and the record was uploaded to the UK Ladybird Survey within minutes. Job done. This was shortly followed by the smaller  Coccidula scutellata, another reed-bed ladybird.

During our circuit of the reservoir we found plenty to occupy us, and a list of species has been supplied to the trust. We finished off back at the classroom where I quickly set a couple of flies to have a look at under the microscope.

All you need is a basic (and cheap) stereomicroscope with low power, nothing fancy.

All you need is a basic (and cheap) stereomicroscope with low power, nothing fancy.

I’ve already come up with my own short list of introductory identification guides, it might need a bit of updating occasionally. This is the one that stands out at the top:

Full of superb pictures and concise clear text, you can see how much wear my copy has had.

Full of superb pictures and concise clear text, you can see how much wear my paperback copy has had.

All in all, an enjoyable day for me, to be able to chat about and demonstrate even quite common insects to an enthusiastic party. More in the future I hope. Thanks to Penny Dixie, a volunteer at the reserve, for taking so many photos. Here is another selection:

 

Small, but perfectly puzzling

You’re just going to have to take my word for it that this was the most interesting insect I looked at down the microscope today.

What's this then?

What’s this then?

Two millimetres long, black, moderately shining, averagely punctured, appallingly carded at an inconvenient skew, it was not immediately obvious what it was. And that was the point. That was why it was interesting.

It’s not very often I look at an insect and can’t even work out what family it’s in. This one just did not look right. My normal method of identification is to think something along the lines of “That’s a ground beetle, maybe an Acupalpus or similar”, “Ah, a robberfly, one of the shiny black ones”, or perhaps “That’s a very small Dolichopodid”. I know where to start — what family, often what genus, and very often which species group, and off I go to find a key or a picture to settle the matter.

But here I was, dithering. I just could not summon up a mental image of which group of beetles this one fitted in with. I started flicking through picture books, but the trouble with small black slightly shining beetles, is that they all  look just like every other small black slightly shining beetle. I peered at the antennae, counted the tarsal segments, eyed up the bristles on the underside of the abdomen, admired the flattened legs. Nothing.

Back to basics then, and a wade through the laborious dichotomous keys to identify which beetle family, until I eventually get to Phalacridae, pollen, flower or smut (fungus) beetles according to which book you use. But I’d already dismissed this distinctive group because it didn’t look like one. Except, now I look again, and trying to overcome my preconceived suspicions read through the descriptions given in volume 3 of the Rev. Canon W.W. Fowler’s excellent Coleoptera of the British Islands (1889) where the key immediately splits off Phalacrus caricis — the only British phalacrid that doesn’t look like a phalacrid because it is not convex and shiny enough.

And that’s what it is. It’s not rare, it’s not pretty, it’s not striking. It’s nothing out of the ordinary, except that it’s slightly flatter and slightly more granular than the others in the family. But I had never seen it before, and it presented a puzzle to me, which I eventually solved.

This, then, is my utter delight in nature. Not finding great big flashy brashy bits of animated insect bling; not rediscovering some rarity last seen a century ago; not seeing the spectacle of mass migration, or observing a deadly pursuit, or a bizarre mating ritual. It is in the simple intellectual puzzle of finding something slightly different, slightly unusual, and working out what it is, and how it fits in with the world.

I’m easily pleased.

The good, the bad, and the downright nauseatingly disgusting

The 2015 Nunhead Cemetery Open Day Bug Hunt has just been and gone and, as ever, one of my main tactics to enthuse children is to emphasize the grim, gory and gruesome nature of insect biology. The more disgustingly yucky the better. Dung flies are always good — they eat what? I was bitten by 20 centipedes (venomous front legs) and half-a-dozen spiders (“can you see how her fangs are stuck in my skin”). We had predatory ground beetles ready to rip apart some unfortunately prey, a hoverfly larva ready to suck an aphid’s innards out, and a lesser stag beetle grub that defaecated right on cue. But it was the parasitic wasp pupa under the ladybird that really caused a stir.

“What’s this ladybird cuddling?”

I was quite excited about this one. The idea of one animal living inside another, and eating it alive from the inside, is definitely the stuff of nightmares. No prizes for guessing where Ridley Scott got the idea for Alien.

We’d already had a couple of parasitoid wasps brought to the bug hunt stall, one with long thin ovipositor, prefect for penetrating deep into the succulent flesh of a caterpillar to lay its eggs. My description got some grimaces, but any disgust was mild, and tinged (as I had planned) with a certain amount of wonder at nature’s inventiveness. No so for Dinocampus coccinellinae, the ladybird killer.

For one thing the ladybird was not dead. It had not been allowed to die. Instead, as the maggot gnawing at its internal organs had grown to maturity, its host had continued to move about and feed, constantly supplying the hungry inner passenger with fresh food. Eventually the parasitic grub had burrowed out through the beetle’s belly to spin a cocoon in which to pupate, but still the live ladybird was in its thrall, gripping involuntarily to the leaf as a protective dome.

Hypothetical caterpillars might be one thing, but here was a helpful ‘friendly’ creature from the garden, the lead character in many a children’s book, a fashionably familiar design on back-packs, clothes, bedding, jewellery, drinking bottles, kitchen timers, hair accessories and novelty chocolates. And here it was, being tormented before our very eyes.

It was at this point that someone asked if this was one of the ‘bad’ ladybirds. Since it was first found in Essex in 2004, the harlequin ladybird, Harmonia axyridis, has been a popular tabloid focus for biological woe, with all manner of garbled non-science about its tendency to out-compete native ladybird species, and even eat them, along with lots of other ‘good’ insects like lacewing and hoverfly larvae. I suspect he was after an answer something along the lines of: “Yes, this is one of those evil foreign bugs, good thing it’s going to die, you should squish any you come across too.” I don’t think he was very impressed by my short lecture on how the concept of ‘good’ or ‘bad’ animals is nonsense to a biologist, and just the artificial construct of an ill-informed sentimental society which has lost touch with nature in all its struggle for survival — disease, decay and death.

It was at this point I realized I might be losing my audience. Perhaps I was being rather too objectively rational, and just a tad overenthusiastic about the detailed mechanics of ladybird parasitism.

Ah well, I made a slight recovery by going on to explain how the harlequin had so explosively invaded Britain, and how this common ladybird parasitoid had only recently started to increase its attacks on the alien beetle, as it became evolutionarily more familiar with the harlequin’s tree- and shrub-dwelling habits, rather than the herbage-inhabiting behaviour of the 7-spot. Anyway, the captor was suitably impressed that I wanted to keep his find, to photograph and rear the parasitoid through.

Secretly, though, I think we need to try and raise the popular understanding of some of the more awkward biological concepts — murder, incest, slavery, gender inequality, caste systems, cannibalism, and being eaten alive from the inside. I realize this is something of a challenge.

What a difference three decades makes

The perspective is not quite the same, but I think you can just make out that Shirley Wheeler is standing in the left-hand of the two bridge spans.

Disused railway line, Poplar, 6 August 1984.

Disused railway line, Poplar, 6 August 1984.

Docklands Light Railway, Poplar, 4 September 2014.

Docklands Light Railway, Poplar, 4 September 2014.

This is the view just north-east of Poplar station on the Docklands Light Railway line heading up towards Stratford. The bridge carries Poplar High Street across the tracks. Just over 30 years separates the two photographs.

The first photo was taken when ‘Docklands’ was just a developer’s wild idea. The second was taken this afternoon. In the summer of 1984 Shirley was looking up at the birds nesting under the eaves of the derelict building — house martins I think they were, or swallows perhaps. We’d spent the day wandering the vast broken landscape of the Isle of Dogs, from Mudchute and Millwall up here to Poplar. Much of the former industry had been bulldozed or had just fallen down in abandonment. Everywhere was a riot of flowers and birdsong. We picked blackberries from the old railway embankments. I found the peculiar plant-hopper Asiraca clavicornis, for the first time. It’s a regular on London brownfields still, but is rare elsewhere in the UK.

The massive redevelopment started soon after our visit, and is continuing even now. Each time I travel on the DLR there is more construction going on somewhere as more plots are infilled. I don’t want to get too maudlin, but I do mourn the loss of what was, at the time, London’s largest nature reserve.

Ivydale’s inse(c)t day

It was the obvious wordplay, so I went with it. They were always called insect days in our house. Inset? what on Earth does that mean anyway? At least ‘teacher training day’ makes some sort of sense.

This way; past stinging nettles, trailing brambles, and mud.

This way; past stinging nettles, trailing brambles, and mud.

I didn’t call it a bug-hunt though (too demeaning for adults) so we indulged in the citizen science that is the bioblitz. But it was a bug hunt really. The hunters were armed with empty humous pots and sent off to see what could be scooped from the herbage of One Tree Hill off Brenchley Gardens.

I’d set up a trestle table and microscope in the small grassy clearing half way up the hill and along everyone came.

Ready to rumble.

Ready to rumble.

Not surprisingly the list of just over 60 species was really quite modest. The site we investigated was very restricted, barely a few hundred square metres of secondary woodland edge and irregularly mown grass and bramble thicket.

Nevertheless everyone seemed very enthusiastic. (Well, I did get a couple of sit-outs “Oooh, I don’t do insects”, slightly disappointing.) There were five species of bumble, including the tree bumblebee, Bombus hypnorum, and one of the cuckoo bumblebees, Bombus vestalis.

The most unusual find of the day was a single small (5.5 mm) metallic green jewel beetle. Agrilus laticornis is notionally ‘nationally scarce’, a denizen of oak woodland (there were some oaks growing here) where its larvae burrow through the bark of dead trunks and branches. It’s always a nice thing to find.

Agrilus laticornis, confirmed by examination of the shape of the prosternal plate behind the front coxae.

Agrilus laticornis, confirmed by examination of the shape of the prosternal plate behind the front coxae. Technical terms obligatory here folks.

One thing, though, became immediately clear — although older, wiser and potentially better informed, the adults could not compete with the keen and crisp eye-sight of their 5- to 12-year-old pupils. Also, being shorter, the children are naturally closer to the ground, always a useful thing when bug-hunting.