Insects

Introducing the Data Dwellers

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Small Observations, Big Possibilities

Sometimes a bumblebee lands on a flower. Sometimes it lands on a map.

Over the past year there have been a number of significant changes in my life, which include a move and diving into a new area of knowledge; Data Analytics. However, one constant has been nature observation. If you decide to take the plunge with me, I’d like to slowly start incorporating these aspects into a new series —one part data, one part nature observation. This series, Data Dwellers, is about the quiet footprints organisms leave across landscapes, and how every recorded sighting builds the bigger picture. Whether it’s a beetle in a field, a dragonfly over a pond, or a butterfly zigzagging through nettles—these aren’t just wildlife moments. They’re coordinates, timestamps, and opportunities.

I’ll be keeping this first entry light, but here’s what you can expect from future posts:

  • Mini-Profiles: Exploring species you might stumble upon, grounded in data and ecology.
    • Data Deep Dives: Looking at patterns, gaps, and what citizen-collected data can reveal about regional biodiversity.
    • Behind the Numbers: Explaining how digital ecosystems (like Observation.org or GBIF) track nature—with all its quirks and blind spots.

Each entry will be tailored to the species I’ll cover, some might benefit with a deep dive into the data available, whereas others will explore issues found within the data available. Furthermore, each entry will compliment posts in the other regular series such as Fly Facts, Butterfly Bulletin, Odonata Update, and more.

1.0 First Glimpse: Bombus inexspectatus in Spain

Here’s a simple visual example of what I mean. I’ve built a dashboard that combines observations of Bombus inexspectatus—a rare bumblebee—from two public datasets. It’s not flashy, but it starts to tell a story and it provides us a basis for excursions and goals we have to see if we can observe the species ourselves out in the wild.

I‘ve not yet been able to embed the dashboard here (yet), but below is an image with a link to that dashboard. The dashboard is interactive and will update by itself if I make any changes to it in the future. Feel free to zoom in on anything that might interest you, check or uncheck boxes, hover over observations or bars in the bar chart for more information.

Bombus_inexspectatus Dashboard

Fig 1. – Link to a Tableau Dashboard of Bombus inexspectatus observations. Data from Atlas Hymenoptera and GBIF. Click on the image to visit the dashboard in a new tab.

Dashboard Notes

  • Mapped Observations: You’ll see locations pulled from GBIF and Atlas Hymenoptera—both great resources with different strengths. I’ll post links below.
  • Yearly Counts: Even sparse data can show patterns (or silences). Why the jump in 2015? Why nothing recent? Questions like these guide deeper research.
  • Data Gaps: Some records are missing timestamps or counts. I’ve kept these in to reflect the reality of citizen science—messy, imperfect, but meaningful.

I’ll cover these questions in future Data Dwellers posts on specific species, as well as in a Data Dwellers post where I’ll cover my work methodology.

2.0 Why This Matters

In a way, species like Bombus inexspectatus are digital ghosts. We know they exist—or existed—but they flicker in and out of view depending on where people look, what they record, and how they choose to share it. This is where Data Dwellers finds its pulse: in the tension between the known, the visible, and the speculative.

As I mentioend above, I’ll be posting new entries under this series—sometimes short snapshots, other times deeper dives. And if something sparks curiosity along the way, feel free to reach out or leave a comment. Nature isn’t just for scientists, and neither is data.

3.0 Links

Each time I create a new dashboard for a species, I’ll be using various sources. One will usually be GBIF, which requires that you provide a link to the data used.

Atlas Hymenoptera – Great source on bees in Europe. The link it to the species-specific page.

GBIF – An open access database with biodiversity information. See here the citation you are required to add:

Creuwels J (2017). Naturalis Biodiversity Center (NL) – Museum collection digitized at storage unit level. Naturalis Biodiversity Center. Occurrence dataset https://doi.org/10.15468/17e8en accessed via GBIF.org on 2025-07-14.

Praz C, Müller A, Hermann M, Neumeyer-Funk R, Bénon D, Amiet F (2025). Swiss National Apoidea Databank. Version 1.7. Swiss National Biodiversity Data and Information Centres – infospecies.ch. Occurrence dataset https://doi.org/10.15468/ksfmzj accessed via GBIF.org on 2025-07-14.

Bakker F, Creuwels J (2025). Naturalis Biodiversity Center (NL) – Hymenoptera. Naturalis Biodiversity Center. Occurrence dataset https://doi.org/10.15468/jgywgc accessed via GBIF.org on 2025-07-14.

Inventaire National du Patrimoine Naturel (2020). ATBI Parc national du Mercantour / Parco naturale Alpi Marittime-Jeux de données provenant de l’ATBI dans le Parco Naturale Alpi Marittime (Italie). UMS PatriNat (OFB-CNRS-MNHN), Paris. Occurrence dataset https://doi.org/10.15468/wzwus6 accessed via GBIF.org on 2025-07-14.

Orrell T, Informatics and Data Science Center – Digital Stewardship (2025). NMNH Extant Specimen Records (USNM, US). Version 1.96. National Museum of Natural History, Smithsonian Institution. Occurrence dataset https://doi.org/10.15468/hnhrg3 accessed via GBIF.org on 2025-07-14.

Mañas-Jordá S, Acosta Rivas C R, Ariño Plana A, Baquero Martín E, Bartomeus I, Bonada N, García-Barros E, García-Meseguer A J, García Roselló E, Lobo J M, López Mungira M, López Rodríguez M J, Martínez Menéndez J, Millán Sánchez A, Monserrat V J, Prieto C E, Romo H, Sánchez-Campaña C, Tierno de Figueroa J M, Yela J L, Sánchez-Fernández D, González M, Bonada N (2025). IberArthro: A database compiling taxonomic and distributional data on Ibero-Balearic arthropods. Version 2.4. Department of Ecology and Hydrology. University of Murcia. Occurrence dataset https://doi.org/10.15470/pqq9oc accessed via GBIF.org on 2025-07-14.

Villares J M (2023). Inventario Español de Especies Terrestres (MAGRAMA). Version 1.5. Spanish Ministry for Ecological Transition and Demographic Challenge.

Occurrence dataset https://doi.org/10.15468/f0qd41 accessed via GBIF.org on 2025-07-14.

Introducing the Data Dwellers

Butterfly Bulletin – Alcon Blue – Phengaris alcon (Denis & Schiffermüller, 1775)

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Introduction

The last post was centred around a chance encounter with a butterfly. I’d not even realised I’d seen it until I got back home and looked at my photos in more detail. Today’s post is about a focused excursion in the hope to see a specific species.

It all starts with setting out a general overview of butterfly species I might come across in Cantabria and listing those all in an Excel. Considering the Alcon Blue is quite a rare species, I then look for scientific articles (PDF format) on the species, which range from a pan-European overview to specific Spanish articles. These documents sit in a neat little folder on my HD and wait for a dreary winter day when I might be inspired to plan some excursions for the warm summer months later in the year …

On that deary day I’ll go through the articles and see if there is more detailed information regarding potential locations where I might find the Alcon Blue. The scarcity of the species means some articles are from the 1960s and 70s (when the province was called Santander, not Cantabria) and come with a short sentence where it was seen. For example, the 1968 source (Agenjo) states “near Herrera de Ibio at 40m”, the problem being that all land around Herrera de Ibio is at least 80m above sea level. We have friends who live in that village, so have made plenty of walks in the country lanes near there and I’ve always kept my eye out for boggy (turbera) areas. There are plenty of those, but I’ve never seen the LHP (larval host plant) at all … I ran into that issue in most other locations I found in documentation. Regarding citizen science web sites, nothing.

So, I had to turn my attention to the LHP (more on that unique relationship below), which I looked up on the citizen science websites (e.g., Observation.org) and I had more luck. From there I turned to Google Maps and scoured potential locations comparing it with what I’ve read in literature, to see how easy it is to get there, some street-view images and so forth.

Then it all came down to waiting for a day, during the butterfly’s flight period, with nice weather (and no other priorities … kids, work, etc.) to head on out, with fingers crossed, to search for the impossible.
All the above led me to the following location (Fig. 1, yes, Cantabria can be stunning).

Cantabrian Coast near San Vicente de la Barquera.
Fig. 1 – The Cantabrian coast, near San Vicente de la Barquera (30TUP80), looking westwards towards Asturias. Notice the traditionally grazed pastures (there is a small group of cows mid left) right up to the cliff edge. Has potential spots to find more small populations of the Alcon Blue. The butterflies discussed below were found in the field behind me. Photo taken 28.vii.23.

The result: moist costal pasture that had continued under traditional grazing methods (cows) and that was assessable via walking path. Phew.

Alcon Blue

The Alcon Blue (Phengaris alcon) is part of a group of butterflies that have an intricate and complicated life cycle. Not only does it need a very specific plant (Gentiana sp.) on which it lays its eggs on or near the flower. It also needs a specific species of ant (Myrmica sp.)!

After the egg hatches, the tiny caterpillar will feed on the plant for a bit, but then it drops to the ground where it starts emitting pheromones (and I think even emits a sound) to attract that specific species of ant. Hopefully, there is an ant wandering around, and when it comes across the caterpillar it thinks that it is an ant larva. Gathering some mates from the ant nest, they drag the caterpillar down into the nest and put it in the nursery with the other larva. There it gets fed by worker ants (via regurgitation) and then goes into the chrysalis stage. When the time comes to emerge, the butterfly high tails it out of the ant nest because as a butterfly it does not emit a pheromone anymore, which means that the ants see it as a hostile entity within the nest. Finally, when the butterfly makes it out, it crawls up a blade of vegetation and pumps its wings full of “blood” to fly off and try to find a mate in the vicinity (it can’t go far because it is so closely linked with the plant and ant).

Male Alcon Blue.
Fig. 2 – Male Alcon Blue (Phengaris alcon). San Vicente de la Barquera, 30TUP80, 38.vii.23. This was just after release, the blue upper sides of his wings are not visible here.

Holy smokes … even with all the above going perfect, there is still so much more that can go wrong, such as the weather, parasites … there is one wasp that exclusively lays its eggs in the chrysalis of the Phengaris alcon, so if the butterfly disappears from a location so will the wasp(!), another link in the chain of super exclusive dependence … anyway, you can see why I just had to find this marvellous little insect …

But it does not stop there … Firstly, Phengaris alcon is often listed as Maculinea alcon in older literature. Nothing too drastic, but it can make searching the internet a bit more complicated.
Then there is debate in scientific circles if Phengaris alcon and Phengaris rebeli are separate species or if P. rebeli is a subspecies of P. alcon. In general, P. rebeli is found at high mountain altitudes (Picos de Europa in Spain) and P. alcon elsewhere. There are many more details around why they should, or should not, be listed as one species but the most important aspect is centred around the IUCN Red List, where P. rebeli is listed as Vulnerable (Vu) and P. alcon as Least Concern (LC), but that is because the latter takes both possible species into account. It is absolutely clear that both should be seen as Vulnerable because it is very easy to wipe out the small colonies of butterfly due to coastal development, or landscape management changes and more. For example, if you see the field where I saw the female and LHP (Fig. 3 and Fig. 1) it needs human intervention through traditional grazing methods at certain times of the year that keeps shrubs at bay, grasses not too long, but the soil quality poor in general (i.e., don’t spray it with fertilizer or manure). This is one of those cases where conservation regulations are not moving fast enough for a species and the only thing that I can do is to publish my findings publicly so that someone can use it to further their conservation cause.

Granted, you could ask yourself why such a demanding species requires conservation effort, but that’s for another blog debate.

This is turning into a long post, and I’ve not even mentioned the day itself … I went to visit the site I’d identified as a good candidate for a population. When I sat down for lunch in a dip in the landscape, sheltered from the wind and in a lovely sun, I noticed a couple of larger than standard blue butterflies flying about. I managed to net one and when I took pictures of it while I had it in a glass container I quickly saw that it might be an Alcon Blue. Double checking my field guide I was overjoyed to find I was correct. I released it, finished lunch and walked a few meters on to an open field where I saw a couple Marsh Gentian (Gentiana pneumonanthe) emerging from the grass (Fig. 3).

Marsh Gentian in field.
Fig 3. – Two Marsh Gentian (Gentiana pneumonanthe) in a steep meadow right near the cliff’s edge. They are the two blueish flowers in the middle. The humid meadow has been grazed by cows. San Vicente de la Barquera, 30TUP80, 28.vii.23.

I walked the field. It was quite steep and ended in a cliff with a 15-20m drop straight into the sea. With the breeze coming in from the sea I was slowly tiring. I was going at a measured pace and spotted a butterfly perched on a blade of grass, a female (Fig. 4)! The difference between male and female is that the male is bright blue on the upper parts of its wings, where the female is dark grey/brown with tiny specks of blue. I checked a couple more flowers for eggs (no luck) and then headed up to the top of the steep field, where I had a snack and rest before heading back to the car.

Since then, I’ve identified a couple of other sites I think could be contenders and come July this year (work and a move of house permitting) I’ll certainly try for more success. The two butterflies I saw last year are the first that have been recorded in Cantabria for over more than 20 years.

Fremale Alcon Blue.
Fig. 4 – Female Alcon Blue (Phengaris alcon). San Vicente de la Barquera, 30TUP80, 38.vii.23. A stunning fairly fresh emerged individual (wings are in excellent condition). You can see the dark upper sides of her wings, the blue flecks are more towards the base and not visible here.

Conclusion

When I released the male that I’d caught, I helped it onto a blade of grass (see Fig. 2), and then sat there for about 5 minutes watching it gather itself. A million thoughts flashed through my head from the mundane to introspective to existential. Even if I was the best poet on the planet, I don’t think I could put into words what went through me looking at a little Alcon Blue. A half hour later, when I saw a female, I was jumping for joy along the cliff edge.

This will be one of those days of my life that I’ll never forget, I just wish others would have been there to share it with me.

Further Reading

  • The Proyecto Lepides Observation.org page is down … nooooo … will ask to see if it can be reinstated.
  • The list of the butterfly books I own.
  • The Dutch Vlinderstichting has a good page on it. The butterfly does not fly in the UK, hence no English-text link to the Butterfly Conservation page.
  • The species is not listed on the IUCN’s Red List, sigh. This needs to be addressed asap.

Butterfly Bulletin – Alcon Blue – Phengaris alcon (Denis & Schiffermüller, 1775)

Butterfly Bulletin – Duke of Burgundy – Hamearis lucina (Linnaeus, 1758)

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Introduction

Now is the time so see them fly. The Duke of Burgundy is a species I’ve been looking for over the past 5-6 years and have struggled to find it. Going back to 2010, there are only 1-2 annual sightings of this species in the region. When I say region, I mean the area we had identified for Proyecto Lepides, which included all of Cantabria, parts of Asturias and País Vasco, as well as a thin strip of northern León, Palencia and Burgos.

In Cantabria I’ve not had any success, even though it is possible. So low and behold my surprise when out on a hike last weekend (June 1st) with the boys and some friends, I snap a rushed photo of a butterfly and only realise when I return home that the photo was of the all elusive Duke of Burgundy … reflecting on the day I’m sure I saw more flying about, but I thought it was some species of fritillary, a little faded. I was mainly rushing between calls from the kids to come help identify a snake (Vipera seoanei), an orchid (Neotinea ustulata) or any multitude of flowers, butterflies and insects out and about. There was little time to crouch in a sunny spot and watch the butterflies bob and weave about, waiting on little blues to land and show me the underside of their wings, or big brown ones to flatten against the warm rocks … ah well, there will be more opportunities to document the Duke. The key thing was that it was a great day out with friends and family … “best hike ever, thanks for taking me on it” was a comment from one of the friends, I could not have asked for more.

Duke of Burgundy

The Duke of Burgundy (Hamearis lucina) is unique within European butterflies, as it is the only one in the Riodinidae (metalmark) family here. Most species in the family live in tropical America and in the tropics of Africa and Asia, not quite the landscape you think of when you see the picture below (Fig. 1).

Fig. 1 – Looking down (in a southeast direction) the gorge made by the Río de Covalagua. In the clearings between the trees is where we spotted the Duke of Burgundy. Pomar de Valdivia, Palencia, 30TVN03. 01.xi.24.

Technically, I was not in Cantabria that weekend, but in Palencia, a kilometre or two from the border with Cantabria … which is actually quite a spectacular area, but I’ll feature it as a future Local Hotspot post on the Páramo de Covalagua (you can translate páramo as moor in English).

Anyway, Hamearis lucina feeds on Primula sp. (such as primrose, Primula vulgaris), which is quite abundant in the area where we live. However, as always, it comes down to the ecosystem, environment and microclimate of an area. So, here in northern Spain the Duke of Burgundy can be found in the hilly, mountainous areas with native, scrubby woodland.

Fig. 2 – Hamearis lucina / Duke of Burgundy. Pomar de Valdivia, Palencia, 30TVN03. 01.xi.24.

The butterfly flies quite early in the season in May and June, which might be a reason for the very low numbers of observations because the influx of tourists (nature enthusiasts from abroad who would be recording their nature sightings) has not yet begun … well, the area where Hamearis lucina flies is not that touristic anyway. I spotted the butterfly around 12.30 in the afternoon and, outside of our little group, there was no one there. We did come across some people walking their dogs later, but numbers remained low.
I guess this highlights a limitation of citizen science observation sites like Observation.org … the numbers of observations of a species are related to the number of users recording their observations in a certain location at a certain time. Only through the likes of butterfly monitoring schemes do you really get good insight into how abundant a species is.
All that said, Hamearis lucina remains a rare sighting in the region, even where the butterfly is more common (central Europe) it flies in low numbers.

Conclusion

I’ve not gone into detail covering the actual insect and meandered along talking about nature observations etc. but I think that is because I didn’t spend much time observing the Duke of Burgundy as it flew around. Does it fly in a determined manner like a Boloria dia (I thought that might be the species I’d taken a picture of) or flop around like a Wood White (Leptidea sp.)? Does it fiercely defend its territory, or does it stay calm, soaking in the sun? I can hazard a guess based on what I thought it was, but I’m not certain. And so, I’ve rambled a bit on what is actually a really exciting discovery for me.

Which brings me to my Species Schedule Excel that I first mentioned in 2023’s March/April review. This was one of the highlight species on it. Up next Lycaena helle (Violet Copper), another one I’ve been looking for the past 5-8 years, and which I feel is probably/unfortunately not around anymore in this region … this coming Sunday, I’ll give it a shot.

Further Reading

  • As always, the Proyecto Lepides Observation.org page to keep up to date on current sightings.
  • The list of the butterfly books I own.
  • The UK’s Butterfly Conservation has a good page on it.
  • The species is listed on the IUCN’s Red List, where for all of Europe it falls under Least Concern (LC), but the assessment for Europe dates from 2009 with the population trend decreasing at that time. I cannot imagine it has gotten any better.

Butterfly Bulletin – Duke of Burgundy – Hamearis lucina (Linnaeus, 1758)

Orthoptera Quarterly – Burr’s Wide-winged Bush-cricket – Zeuneriana burriana (Uvarov, 1935)

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Introduction

The previous Tuesday post’s common species found across large parts of Europe; we go to one found only in the Cantabrian Mountains region. The goal today is to set us up for the upcoming Nature 101 Biogeography post. Well, and to show you an interesting species you can find here.

Orthoptera, in regular language grasshoppers and crickets, have not been a part of any extensive scientific studies in the region, so any distribution maps have massive gaps in them. This makes it a difficult order to study here without having in-depth knowledge yourself … where can I best find suitable habitats for specific, maybe rare, species? To give a bit of an indication, a new species was found in 1992 in Cantabria, which has a very restricted distribution, it is called Metrioptera maritima and is closely related to today’s species …

Burr’s Wide-winged Bush-cricket – Zeuneriana burriana

Before we go any further, lets quickly cover the naming aspects.

Order – Suborder – Family – Genus

Orthoptera – Ensifera (crickets only) – Tettigoniidae (katydids/bush crickets) – Zeuneriana

Zeuneriana burriana is also part of a genus group of crickets that all have fairly similar characteristics called Metripotera (to which Metripotera maritima also belongs). Now, I’m not going to go any deeper into this because it gets quite complicated how the taxonomy came about, but if you are interested there are plenty of scientific papers and web sites that can help you learn more. I’ll put some links below.

Picture of male Zeuneriana burriana.
Fig. 1 – Zeuneriana burriana, male. Mazcuerras, Cantabria, 30TVN09. Normally, the long antenna mean that it is a cricket and not a grasshapper.

Most of the species within the Metrioptera genus group have an extremely limited range. Within Zeurneriana there are only 4 species, of which today’s focus species has the largest range. For example, Zeuneriana marmorata (Adriatic Wide-winged Bush-cricket) is only found in a tiny region in northern Italy and Slovenia and is listed as Endangered (EN) on the IUCN Red List.

Zeuneriana burriana is rare, though found in Cantabria, Asturias, the Basque County, Leon, Galicia, and a tiny bit of France. It is found in humid, uncultivated grasslands. I’ve seen it in El Minchón (here is a link to the Local Hotspots post) and “rough” areas around flower-rich fields used for hay. The taller the grasses the better, as normally I’ll be wading through grass that easily reaches my hips.

Cerci of male Zeuneriana burriana.
Fig. 2 – Zeuneriana burriana. Detail of male cerci.

I am not good at identifying grasshoppers and crickets, so usually ask for help from experts on the various forums. What makes the Metrioptera genus group so difficult is that when the insects are not yet adults, so in their nymph stage and the wings have not yet fully formed, they are very small and have very similar characteristics. The best way to ID species is to get good pictures of the male appendages (called cerci) at the end of the abdomen (Fig. 2). The females have a dagger-shaped ovipositor at the end of their abdomen (not used for stinging! Egg-laying only), however, I am not sure how to tell the difference between species when it comes to females. It probably has to do with the curve/shape of the ovipositor.

Conclusion

Orthoptera are difficult, but that should not hold you back from getting interested and informed about them. They are stunningly beautiful when you really get into the details, not just brown or green insects, but with flashy yellows, blues, and oranges. As mentioned, many are only found in very specific habitats (e.g., dune landscapes) so it is also a great way to be introduced to this style of nature observation, where you plan a day out to visit one or two specific areas and take your time investigating them (e.g., learning where to look etc.). You really start to learn a lot doing this, building up your knowledge base for when you go visit more generalised areas where you can spot a wider variety of species.

Another post where I’ve tried to keep it short and to the point.

Further Reading

I mentioned previously that there can be difficulties identifying Orthoptera, especially in the nymph life stage, where even there I think you’ll struggle to get definitive answers. Here are some sites:

Orthoptera Quarterly – Burr’s Wide-winged Bush-cricket – Zeuneriana burriana (Uvarov, 1935)

Bee-news – Shrill Carder Bee – Bombus sylvarum (Linnaeus, 1761)

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Introduction

Hymenoptera (or wasps, bees, and ants as some might call them) can be really difficult to identify. Not only due to their small size but also due to the similarities between the species. Bumblebees (which fall under bees) are no different. Add to that fact that documentation of bumblebee species in Spain, and as always in this area of Spain, is spotty at best. As well as the fact that bumblebee species look differently here, as they do in other parts of Europe (differences in band colouration can be striking due to the multitude of subspecies present). Ugh, why did I start looking into this group of insects then if they only bring headache when trying to identify them? Long story for another day, but this site is named after a species of bumblebee (Bombus cullumanus) …

Bombus sylvarum (female), 24.vii.2016 - Cabezón de la Sal, Cantabria.
Bombus sylvarum (female) on Mentha sp. (a mint), 24.vii.2016 – Cabezón de la Sal, Cantabria.

Shrill Carder Bee

So its English name comes down to the high-pitched sound it makes while flying around flowers, it really is distinctive. The species usually flies a bit later in the year/season than other bumblebees, I usually see them in August to October, but have seen them flying earlier.
They are quite common around the village where I live, as they need “rough” farmland with lots of different types of flowers … therefore, due to agricultural changes, across most of Europe Bombus sylvarum is struggling a bit. In Spain, the occur in the northern stretch along the Cantabrian Mountains and in some higher altitude areas along the east coast and towards Madrid. Apart from near my village I’ve also seen them along the coast (Cuchía), in the mountains (Alto Campoo ski resort) and in Palencia.

There aren’t any big differences between males and females. The most distinguishing characteristic is the black band between where the wings attach to the thorax. However, as previously stated, depending on where you live IDing the species can be difficult. For example, it gets more complicated here at higher altitudes, as there are other bumblebee species that might look similar. At lower altitudes it is reasonably certain, especially if you can hear the bee flying around too.

Bombus sylvarum (female) on Trifolium sp. (a clover), 10.v.2020 – Cabezón de la Sal, Cantabria.

Very Rare Form

Sometimes you can spot an unusual variation of a species (called forma – abbreviated as f.), which will have a specific name. Some variations can be fairly common, as they might occur due to climactic variation, but others can be very rare. I’ve been lucky to spot a Bombus sylvarum f. nigrescens. Initially I had no idea what it was because the coloration did not fit with anything that I might find in this area. The only reason I found out the species was because I got into contact with Leopoldo Castro, the bumblebee expert in Spain, and he was able to ID it for me, not 100% certain but highly probable.
In the picture below you can see the thin light-yellowish bands that it has (running along the edges of the tergites) within the mass of black hairs on the abdomen, with a bit more around the connection between thorax and abdomen.

Bombus sylvarum (male) on Centaurea sp. (a knapweed), 10.ix.2016 – Mazcuerras, Cantabria.

Further Reading

  • The IUCN Red List page – general information about the status of the species in Europe.
  • Atlas Hymenoptera – the best site on information and distribution of Hymenoptera species in Europe. Run by Pierre Rasmont, Belgian expert.
  • Bumblebee Conservation Trust – page on the trust’s site dedicated to the species in the United Kingdom, where it is a rare bee.
  • Steven Falk’s Flickr page – he wrote the field guide for bees in the UK. Awesome photos, great resource.
  • Observation.org – citizen science website that would benefit from your contributions. You can find all my observations there.
Bee-news – Shrill Carder Bee – Bombus sylvarum (Linnaeus, 1761)

Odonata Update – Orange-spotted Emerald – Oxygastra curtisii (Dale, 1834)

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Introduction

The year was 2015 and it was one of those chance meetings. Something flew by, landed on a desiccated bracken leaf for a few seconds and then flew off. In those split seconds I was able to wrestle with a camera I was not familiar with (my partner’s) aim it where I thought that something had landed and take one, single, photo. I didn’t really know how to use the camera, so it was not until I’d uploaded the picture to my computer that I could see I’d taken a reasonable picture of a dragonfly … back in 2015 I was new to all of this so had no idea which species it might be and with no books on the subject searched internet … with little success. I posted the picture to Observation.org and then went to the Dutch forum the site has to ask is anyone might know what I’d taken a picture of. They quickly helped me out there, as it was quite easy to identify … if you know what to look for … but it still did not dawn on me just what it meant.

Oxygastra curtisii (male), 27.vi,15 – Río Saja, Cantabria.

I had slowly been scouring the internet on PDFs, articles, etc. for species on insect and animal that were present in either Cantabria or the general region of northern Spain. I’d also check the IUCN Red List to see if I could find anything there.

A little over a year later, during a visit to one of my favourite parks to spot wildlife, I was walking back to the car with my partner and our kids, and something zipped by us and landed in front of us on the path. I took my (new) camera and we all stood very still while I took a few pictures, as we inched closer it flew off. Again, I had a hunch it was something interesting … back at home I saw that it was a female of the same species I’d seen a year earlier …

Orange-spotted Emerald

The family affiliation of Oxygastra curtisii (Dale, 1834) – Orange-Spotted Emerald in English – is uncertain but it does fall under Anisoptera, which is a suborder of Odonata that includes all true dragonflies (as opposed to damselflies – Zygoptera). So, it is a bit of a unique species, although it does look a bit like Somatochlora (Striped Emeralds) and Cordulia (Downy Emeralds) – both of which do not really occur here on the Iberian Peninsula. On top of that, the Orange-Spotted Emerald is only found in south-western Europe and small populations in Morocco (Northern Africa).

Oxygastra curtisii (female), 10.vii,16 – Cuchía, Cantabria.

It needs slow moving rivers to breed in, which does fit this area of Cantabria where the rivers have calmed down a bit on their way to the Cantabrian Sea after having rushed down the mountains nearby. But the waters need to be really, really clean for it to have a chance to survive and until the early 2000s the factories were not always focused on dumping clean water into the rivers here. This has changed and improvements have been monitored by local organisations here, so who knows, we might start seeing an increase in sightings. It still remains incredibly rare here in Cantabria and I have tried to spot another, but to no avail so far …

However, the IUCN Red List classifies the species as Near Threatened NT and that assessment is probably right on the money. It is also listed as a protected species in Spain.

Our Article

So, the observations were so interesting we, when I was still part of Proyecto Lepides (organisation now defunct), decided to send a scientific article to a reputable publication here in Spain, the Boletin Sociedad de Entomologia de Aragon (or SEA). Jorge Garzón wrote it in Spanish after I sent him an English version of the events. He dressed the text up a bit so that it was all a bit more official, as I’d never done something like it before. I’m still super proud of it and I see it as part of the foundation to help justify all the time I’ve spent out in nature, observing, having fun … there’s nothing like a little recognition for your work … now if I could only publish more articles … hmm … (stay tuned).

Further Reading

  • Klass-Douwe B. Dijkstra, Asmus Schröter & Richard Lweington (illus.). Field Guide to the Dragonflies of Britain & Europe – 2nd edition. 2020. Bloomsbury, 336 pp. – Pretty much the go-to guide at the moment. Pretty stunning book.
  • Christophe Brochard, Dick Groenendijk, Ewoud van der Ploeg, Tim Termaat. Fotogids van Larvenhuidjes van Libellen – 2e druk. 2016. KNNV Uitgeverij. 320 pp. – In Dutch but great pictures of the skins (exuvie) Odonata leave behind.
  • Christophe Brochard, Ewoud van der Ploeg. Fotogids Larven van Libellen. 2014. KNNV Uitgeverij. 236 pp. – Same as the above, also in Dutch, but then of living larva of Odonata. Again, stunning photos.
  • My SEA article that I wrote together with Jorge Garzón.
  • A list of sightings in our area on our (now defunct) project page of Proyecto Lepides on Observation.org.

Odonata Update – Orange-spotted Emerald – Oxygastra curtisii (Dale, 1834)

Bee-news – Early Bumblebee – Bombus pratorum (Linnaeus, 1761)

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Introduction
I was going to write about one of my favourite bumblebees next, but due to the season (early spring) I thought I’d write about a species that starts showing up at this time of year and is actually not all that common in this area (Cabezón de la Sal, Cantabria, Spain).

Early Bumblebee
Bombus pratorum belongs to the subgenus Pyrobombus. The queens are relatively small and one of the earliest to appear each year (as the name might suggest). Queens pop out with regards to colours as the orangey tail makes them look a bit darker and more drab when compared to the whitish tailed bumblebees that are also out. The yellow bands are a crisper colour yellow.

Early Bumblebee (queen) on an unknown plant in Cantabria, Spain.
Early Bumblebee (queen) on an unknown plant in Cantabria, Spain.

Males are fuzzy balls of yellow, with yellow hairs on their heads and with an orangey tail.
I have yet to see a worker.

Early Bumblebee (male) on a dead nettle (Lamium sp.) in Cantabria, Spain.
Early Bumblebee (male) on a dead nettle (Lamium sp.) in Cantabria, Spain.

The subspecies B. p. santonae can be found on the Iberian peninsula, but I have no idea what the differences are, but it is the only subspecies found here. If I compare my pictures with those found in the Falk link (see below) then here the bees have more extensive yellow bands.
There is conflicting information on this subspecies and I do not really know which is correct. Some sources state that this is a higher altitude species (500m+ above sea level), but I’m at around 100m. However, I do not know which other species it could be (see Complicating Factors below). Furthermore, there are very few pictures on the internet.

The one thing that could help me out it a book called Fauna iberíca. Vol. 23. Hymenpotera: Apoidea 1 by Ortíz-Sánchez and Ornosa, but it is costly and in Spanish.

Sigh, bees are not that well detailed in Spain as butterflies are and information is difficult to obtain. Once I find out more I’ll post a follow-up article, as this one’s pretty poor with regards to actual information! haha

Complicating Factors
So, not only is it difficult to find out what B. p. santonae actually looks like, but apparently the subspecies of the Red-tailed Bumblebee (B. lapidarius), which is called B. l. decipiens, has the same colouration in queens! However, they are also normally found at higher altitudes (apparently) here and queens emerge much later (May). Furthermore, they are bigger, but this is something you can only really pick up once you have gained quite some experience out in the field. After only one summer season, I am still far from that required level.

So, I guess the bumblebees I’m seeing are Bombus pratorum santonae, but at the moment I cannot be 100% certain. All I know is that the UK situation is a lot simpler.

Further Reading
– Here is a link to Steven Falk’s Flickr page, lots of good pictures and basic info. He has a good book out on Bees in GB & Ireland!
– A link to P. Rasmont’s page with a distribution map and some other basic info.
– A link to the Natural History Museum page that gives an overview of the colouration of the Early Bumblebee.
– A link to the IUCN page. Great site.
– The Bumblebee Conservation Trust is a great organisation, especially if you live in the UK, they’ve got a helpful site for the beginner and also a place to upload photos and ID other people’s photos. I’m a member even though I live abroad.
– There’s a cool app for the iPad/iPhone by NatureGuides with great drawings. I’ve got the Pro version which has been a good resource for info.
– Dave Goulson’s A Sting in the Tail is a fun read about the world of bumblebees.
– My sightings to date on Observation.org of this species in Cantabria.

Bee-news – Early Bumblebee – Bombus pratorum (Linnaeus, 1761)

Book Club – A Buzz in the Meadow by Dave Goulson

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Introduction
This is actually the second book I’ve read by Dave Goulson, however, it is the one I’ve finished most recently and hence will cover the other book (A Sting in the Tail) at a future date.

As for other books to come through the review, over the past couple of months I purchased some field guides and natural history books, and am currently reading John Fowles’ The Collector, which is maybe not directly a “nature” book but is pretty good and about a butterfly collector, sort of …

Comments
As I stated above, this is the second book I’ve read by Mr Goulson. It is also his second book and follows up nicely from the first with many links between the two.

In 2003, Mr Goulson purchased a farm in France that came with 13 hectares (130,000 m2) of land. Since then he’s been working on the buildings and slowly letting the land get back to a more natural state of flowery meadows … although he has created a little brook and pond to attract wildlife that needs water (e.g. dragonflies). The main thing is that he’s letting the land recuperate after being fertilised and treated with pesticides etc. throughout the time that it was “productive” land for the farmstead.

The book is divided into 3 sections. The first (and longest) consists of 9 chapters covering the animal (mainly insect) life to be found around the farm. This includes bees, butterflies, dragonflies, beetles, newts etc. Birds aren’t really covered. The second section (3 chapters) is about plant life and the last section (also three chapters) is how the natural world is interlinked and what man’s effect has been on that natural world.

Each chapter starts on one topic, but often it meanders from there on, going from one related subject to the other. It is like listening to someone extremely knowledgeable on a multitude of topics and that person is excited to tell you something and then he or she just continues talking and you have the feeling they can go on for ever.
Mr Goulson has a pleasant manner of writing, which explains everything quite clearly and thus it becomes quite fun to read the book. So much so that at times I had to stop myself from reading, as there is an overload of information and it becomes impossible to remember all that is told. In other words, I’ll probably re-read chapters on specific topics in the future to remember what was said.

I enjoyed this book and it inspired me, but hey, I was probably going to enjoy the book anyway considering my interests … It was a fluid read, even though some subjects can be quite scientific, but it is never boring. The only thing is that I sometimes longed for more, but I think this is inherent with nature, in that it will take many more years before the farm gets to full potential and Mr Goulson discovers all the interesting things happening in the fields, as everything needs time to adapt, change and grow. For example, he’s doing an experiment over various plots (to do with growth of plants), but it a will take many seasons before the results are finally known and a bit more conclusive. I can easily see a “part two” in 10 years time to give us an update on how the farm’s changed.

The Edition
Title: A Buzz in the Meadow: The Natural History of a French Farm
Author: Dave Goulson
Publisher: Picador
Year: 2014
Edition: Hard cover, first US edition (2015), 1st printing, 265 pages
Additional Info: Includes index.

Further Reading
– Dave Goulson’s Twitter page.
– Mr Goulson’s page at the university where he works.

Book Club – A Buzz in the Meadow by Dave Goulson