It's June, so it's Peak Bioblitz. Much of my activity this month has been dominated by organized group visits and walks. Sadly the results have been dented by the heat and ongoing drought.
Apart from sleeping, I'd almost welcome more tropical nights.
May has been a busy month, dominated by bees. I am thankful for the relief from the spring drought at the end of the month.
So far so easy - I know the flowers I have taken the pollen from. But can I identify pollen taken from bees to work out what they have been feeding on? There are several useful websites for identifying pollen. The Global Pollen Project is good, but my favourite is the Northumbrian Bees pollen gallery.
By coincidence, this month's Microscope Club also involved messing around with pollen and as usual, I picked up some useful tips. Size as well as shape is a key feature of identifying pollen grains and the standard is to make sure the pollen is fully hydrated before measuring, thus aqueous media are used. Glycerol Jelly is the standard medium but is a pain to work with, so I'm using Magnacol aqueous mountant. In water alone pollen grains are quite frisky and move around, making photography difficult. The Magnacol mountant contains PVA and is quite viscous, which fixes the grains better.
This is very much a work in progress but it will be interesting to see what I can find as the season progresses (assuming there are enough hours in the day).
Where the bee sucks, there suck I:
In a cowslip’s bell I lie;
There I couch when owls do cry.
On the bat’s back I do fly
After summer merrily.
Merrily, merrily shall I live now
Under the blossom that hangs on the bough.
I'm troubled by the ongoing demise of traditional wildlife groups, the sort that (used to) meet in a village hall once a month. I observe them gradually blinking out, one by one. I don't have any magic solutions for this (maybe there are none), here I'm just whistling in the dark to console myself and using this as a sketchpad for ideas.
What is keeping local natural history groups alive? Mostly, talks on "I jetted off to an exotic location buring tons of carbon to photograph wildlife". Ironic, isn't it?
Characteristics of thriving wildlife groups:
But:
Communities don't live forever, they have lifetimes (particularly since most are maintained by a small number of enthusiasts). Individual members' life circumstances change, so communities evolve (rather than die). This is a tough process for individuals - natural selection - but inevitable.
So where do we go now? DOBS
Please insert your thoughts here:
Kleidocerys resedae, the Birch Catkin Bug, is a familiar and very common species of Lygaeid. Two closely related species are more problematic. Kleidocerys ericae was differentiated from K. resedae based on pigmentation and the fact that it feeds on heathers (Erica spp but not Calluna so I'm told). Kleidocerys privignus also has a different pigmentation pattern and feeds on Alder (Alnus). My natural inclination is to be a taxonomic lumper so I'm inclined to disregard the pigmentation differences (intermediate forms occur) and the food plant preferences (which laboratory rearing experiments have shown are not absolute) and regard all three as a single species. My ultimate authority on Hemiptera, Pericart, wasn't sure about these three, and without the benefit of DNA analysis hedged his bets, so no clear answer there. I was able to live with that until recently when I did some DNA analysis which implies that all three are indeed distinct species, see: https://ajcarthropoda.blogspot.com/2025/02/the-kleidocerys-conundrum-resolved.html
Which brings us to the question at the heart of this - what is a species? These days, the answer depends a lot on who you ask, but everyone agrees that it's now a lot more complicated now than when the species concept was developed. I'm afraid I have the old-fashioned opinion (which is bound to upset some) that a species is a group of organisms which are reproductively isolated. There are lots of ways to be reproductively isolated, e.g. pioneers trapped on an island, but it is also possible to be reproductively isolated behaviourally. A good example of this is the wolf spider Pardosa lugubris. This was split into two species based on observations of the male courtship dance (Cryptic species and behavioural isolation in the Pardosa lugubris group (Araneae, Lycosidae), with description of two new species. (2000) Bulletin British Arachnological Society, 11(7), 257-274). Being eaten by the female if she rejects your dance moves is pretty strong selection leading to reproductive isolation. Which brings us to Kleidocerys again. Like many Hemiptera, Kleidocerys communicate by stridulation. In this genus, sound production may not to be associated with mating but occurs when they are disturbed, perhaps as a territorial statement. K. ericae stridulates at a frequency of 16 Hz while K. resedae uses a lower frequency of 8 Hz (Stridulation and its analysis in certain Geocorisae (Hemiptera Heteroptera). (1957) Proceedings of the Zoological Society of London, 129 (3): 351-358). This is equivalent to the Pardosa mating dance and is likely to cause reproductive isolation, which is borne out by the DNA analysis of the two species. I don't know about stridulation frequency in K. privignus but the DNA analysis means that if we accept K. ericae as a distinct species from K. resedae, we have to do the same for K. privignus.
Recently I sampled 20 Kleidocerys specimens from Alder here in Leicestershire. My overall impression is that they are quite variable in pigmentation, but in my sample, 1 out of 20 specimens has the pigmentation described for Kleidocerys privignus, the others appearing to be variants of the extremely common Kleidocerys resedae.
The upshot of all of this is that while it's not clear if K. ericae occurs in VC55 (we have limited heather here), I think it's clear that K. privignus does. Now we need boots on the ground to get out there and figure out the field ecology.
Many thanks to Jim Flanagan for helpful discussions, and for sharing this interesting paper:
Davranoglou, L.R., Taylor, G.K., & Mortimer, B. (2023) Sexual selection and predation drive the repeated evolution of stridulation in Heteroptera and other arthropods. Biological Reviews, 98(3), 942-981.
April has been a busy month for me, but here are my highlights.
Last night I gave a talk to a local wildlife group which unexpectedly turned into a discussion about insect decline. It had to be said but that doesn't mean I like saying it. If you were in the audience, I apologise again. Seeking solace this morning, I visited my favourite wood. Over the last few years this has been depressing as Ash Dieback has gradually decimated them. Today I discovered that most of the dead Ash has been removed, and the transformation from dank Ash woodland into a very open, light-filled Oak woodland was startling and marvellous.
A variable month, weather-wise - frost at night but some days very Spring-like. Blossom and buds bursting, but with the cold nights only one moth in the first moth trap of the year.
Recovered grasslands need more than 75 years of continuous management to regain their biodiversity because specialized pollinators are slow to return (also applies to fungi, etc, e.g. waxcaps). This underscores the importance of preserving old grasslands as reservoirs of biodiversity. Don't let developers tell you otherwise!
Long-term management is required for the recovery of pollination networks and function in restored grasslands, Journal of Applied Ecology (2025). DOI: 10.1111/1365-2664.70017
The Olympus M.Zuiko Digital ED 75-300mm f/4.8-6.7 gets looked down on by Olympus snobs because it's "not as sharp" as some of the much heavier OM Pro lenses. I've just picked up an excellent used copy of one of these compact, light, cheap (everythng is relative!) lenses. So what do I think?
For just over £200 I've got a 600mm full-frame equivalent lens which is capable of photographing a bird at the top of a tree, or at closest focus filling the frame with a 10cm long subject. And by clipping a Raynox DCR250 lens on the front I can get 1.5X magnification, filling the frame with a 1.5cm long subject. My reason for buying this lens is not to photograph birds though :-) This is the lens I want for photographing flying insects - dragonflies, butterflies, hoverflies - if only there were some flying insects around at present!
But is it sharp enough? I'll let you decide:
click for larger image
Since the pandemic the number of dogs has exploded, and with that, the amount of environmental harm being caused. I've seen so much habitat degradation over the last few years, associated with much heavier traffic than years ago. I don't blame the dogs for this. Working from home also plays a large part... The question is, what are we going to do about it?
Unleashed: walking dogs off the lead greatly increases habitat disturbance in UK lowland heathlands. (2024) Urban Ecosystems, 1-10. https://link.springer.com/article/10.1007/s11252-024-01568-4
Abstract: Human population growth is associated with increased disturbance to wildlife. This effect is particularly acute in urban and periurban areas, where the area of effective disturbance extends beyond that of human presence by the roaming behaviour of pet dogs. Dogs are globally the dominant companion animal, with a population of ~12 million in the UK. As urban areas extend, dogs are exercised in green space close to housing. In southeast and southern England these areas include lowland heath, a habitat of high conservation value. To quantify disturbance caused by dog walkers and their dogs, we used GPS units to track the movement of people and their dogs across four lowland heath sites, used a questionnaire to ask about dog walking habits, and mapped potential areas of disturbance caused by dog walkers. Questionnaires were completed by 798 dog walkers and the walks of 162 owners and their 185 dogs were recorded. Mean (±SE) walk time was 56 ± 23 min, walk distance 3.75±1.68 km and dogs were a median distance of 20 m from the owner during walks. Dogs were walked once (44%) or twice (56%) a day. Most (always: 85%; always or occasionally: 95%) dogs were walked off the lead even when signs were present requesting that dogs were kept on a lead. This resulted in up to a 21% increase in reserve area disturbed. In one reserve (Snelsmore Common), >90% of the area was disturbed by dogs, greatly eroding its conservation value. This work highlights the importance of considering how dog ownership can exacerbate levels of disturbance in sensitive periurban habitats when housing developments are planned.
There's useful information on Managing visitors with dogs in your woodland from WWW.GOV.UK here.
A new research paper shows a large and significant negative effect of the major plant nutrients (NPK) on the abundance, species richness and functional diversity of both pollinators and flowering plants. Even average use of nitrogen fertilisers cut flower numbers fivefold and halved pollinating insects. This isn't a novel finding but the data presented is incontrovertible. This helps to explain the lack of biodiversity in huge swathes of VC55.
Trade-off between pollinator-wildflower diversity & grassland yields. npj Biodiversity volume 4, Article number: 1 (2025) https://doi.org/10.1038/s44185-024-00070-6
Macro photography has been hugely improved by the development of "flying nun" flash diffusers (such as Cygnustech diffuser, AK, MK, etc - good comparison here: https://wildmacro.de/the-best-flash-diffusers-for-macro-photography/). The closeness of the flash to the subject causes hot spots and burnt out highlights, and shiny subjects such as beetles are particularly difficult. The curved diffusion surface helps to solve these issues.
On a recent outing Arthropods were very hard to find, but while searching I spotted some pink dots on a lichen-covered twig. It was one of those occasions when I knew exactly what it was, the lichenicolous fungus (a fungus which is a parasite on lichens) Illosporiopsis christiansenii. You might think day-glo pink fungi would be hard to overlook, but sizeism kicks in and they are usually overlooked because of their small size. I've been looking for this species and while it's not rare I've not seen it before. There are a couple of species it could be confused with so to confirm I checked the characteristic coiled spores under the microscope.
Recently I wrote about buying a new camera which required some practice, but after a few days of household items such as pencils and peppercorns, I was desperate for some insects to photograph. My first outing immediately after the snow drew a complete blank, so I had to wait a couple of days for it to warm up before bothering the Ivy in the garden.
As luck would have it, the very first thing I found turned out to be Dioxyna bidentis, the Bur-marigold Fly. This turned out to be the first record of this species for VC55. Even odder, there's no Bur-marigold around here, but some research told me that the larvae of this species develop in the flower heads of a range of Asteraceae. Here, I suspect that's my carefully cultivated Ragwort (at least, what survives annual decimation by the Cinnabar Moth larvae).
This odd coincidence makes me wonder what would happen if Jennifer Owen were to repeat her 30 year study - how different would the results be?
This is a long and detailed post about photography (macrophotography specifically), you can skip this if you're not interested.
A year ago I bought an Olympus TG-6 camera for macro photography (What *another* camera? Olympus TG-6 review). This pocket camera has turned out to be a very good buy and I've used it more and more, often in preference to my full Sony macrophotography setup due to convenience. It's the first "Olympus" camera I've ever owned, although Olympus cameras ceased to exist a few years ago and the rights were bought by an entirely new company, OM Systems (but if you say OM to non-photographers you get blank looks, so people still call them Olympus - don't tell the lawyers). Over the last year OM kit has gone from strength to strength, particularly in macrophotography, while Sony has dropped the ball to some extent and is now about the only camera company not to introduce in-camera focus stacking. This is a shame as I've got a big investment in Sony cameras but I've finally given up waiting.
The Technical Bit: Digital cameras with 35mm sensors are referred to as full frame (the same size as photographic film). As sensors improved, a new smaller sensor format emerged, APS-C. The advantage of these smaller sensors is that the cameras, and in particular the lenses, can be smaller and lighter. An even smaller format, micro four thirds, was released by Olympus and Panasonic nearly 20 years ago, allowing even smaller and lighter systems. There is a price to pay. Smaller sensors are less efficient at light gathering than big sensors and so micro four thirds cameras are light hungry.
As I get older (don't tell anyone) equipment weight becomes a more important consideration for me, although this is secondary to the value of in-camera focus stacking, which a year with the TG-6 has convinced me about. The OM flagship system is the OM-1 with the M.Zuiko Digital ED 90mm f3.5 Macro IS PRO lens, and macro photographers are achieving stunning results with this, but for me it has two problems. My equipment-buying philosophy is to buy good condition used kit from reliable resellers, generally one or two models down from the lastest top of the line models. This generally costs a third to half the price of the latest shiny kit and has served me well over the years. The 90mm macro lens isn't generally available second hand yet and a new OM-1/90mm setup is three thousand quid. No. There's an even bigger (literally) problem. The OM-1/90mm setup is almost the same size and weight as my Sony system, so the only advantage is the focus stacking.
So I bought a used OM-5 and M.Zuiko Digital ED 60mm F2.8 Macro lens. The price was much more reasonable and the weight (610g) is half the weight of my Sony kit (1077g). Coming from the Sony FE 90mm F2.8 Macro lens the OM 60mm feels like a toy, but certainly doesn't behave like one. (Update: I subsequetnly traded the 60mm lens and the Sony macro lens for a OM SYSTEM M.Zuiko Digital ED 90mm f3.5 Macro IS PRO).
Inevitably, having changed manufacturers, there were all sorts of extra bits I had to buy - batteries, filters, etc. This was expected, but then I hit a problem. My Godox flash (Sony version) didn't work with the OM-5. I wasn't sure about this but sadly these things all have proprietary fittings. As I said, micro four thirds sensors are light hungry, macrophotography even more so, thus a new OM-compatible flash was an unavoidable extra expense.
All photographers moan about camera menu systems but after a year with the TG-6 I thought I'd be OK with the switch to the OM-5. In fact, it proved to be a pretty steep learning curve and I'm still dialling in on the best settings for me. The 60mm macro lens is pretty good, although for my needs it lacks a little bit of magnification so I'm pushing it further with some add-ons. The micro four thirds sensor imaging area is 17.3x13mm and the maximum magnification of the 60mm lens is 1:1. Adding a Raynox DCR150 lens gives 1:1.3 magnification (13mm long subject area) and a Raynox DCR250 gives 1:1.5 (11mm subject area). I can increase this more with extension tubes. I've still got a way to go practicing with this new setup but I'm getting there. It seems to work (click for larger image):
If you went to a Michelin-starred restaurant and ate the most delicious meal of your life, would you ask the chef ,"What oven do you use"?
I'll be honest, Hymenoptera give me the heebie jeebies, but ants surely have to be the most fascinating group of insects which have yet evolved. I'm naturally drawn to under-recorded groups and ants are very much neglected in VC55. With only 61 species occurring in Britain they are also a manageable size (compared to say, Ichneumons). But I must resist, I've made a deal with myself that I'll get to ants after I've sorted out aphids (but don't hold your breath!). When the day comes I won't be able to do better than Gary Skinner and Andrew Jarman's updated Ants book. In fact, I could splurge a lot of money on the Naturalists Handbooks Series ... but I must resist!
Skinner, G.J. & Jarman, A.P. (2025) Ants (Naturalists Handbooks Vol. 24). Pelagic Publishing Ltd. ISBN 9781784273040 https://pelagicpublishing.com/collections/naturalists-handbooks/products/ants-second-edition
Not a lot of entomology for me this month, I've been mostly thinking back on this year as well forward to 2025.
I've never kept a regular journal for a whole year before so this has been an interesting exercise. While it's nice to be able to recap the year easily, it hasn't been an easy process for me. I'm not a natural diarist and this journal has been rather selective. To be able to keep this up I need to make some changes, and from January I won't be writing a full journal each month, but I do want to continue on a more advanced ad hoc basis, so in future months it will be more of a digest than a diary.
Low carbon biological recording - and remembering sunny afternoons in the garden.
First VC55 record for the Ray Spider, Theridiosoma gemmosum.
My Journal, December 2024
03.xii.2024
A local trip to the Attenborough Arboretum. Not much to be found but lots of Giant Willow Aphids. After some effort I did manage to confirm a record of Mycena calvularis on a Willow trunk, a good result for my rusty mycology.
09.xii.2024
Weather pretty bad, so a week of microscope work catching up on the summer backlog.
13.xii.2024
LRES first ever online meeting on Aquatic Bugs seemed to be well received by guests. The members were possibly less keen on this format.
17.xii.2024
Went on a secret mission to a secret location to collect a secret species for a secret project! Sorry, but I hope to have an exciting update in 2025!
29.xii.2024
After two weeks of the gloomy weather I can remember, finally a pink dawn and some sunshine. With the days getting longer, a prospect of hope on the horizon for entomology in the year to come.
