In search of the endangered Bombus brodmannicus bumblebee

This delightful blog was written by Pieter Haringsma who was inspired to search for this bumblebee after reading our Bumblebees of the World blog on Bombus brodmannicus by Denis Michez last year. Pieter often provides the Trust with beautiful, captivating images of bumblebees and is definitely and expert in this field!

As a Dutch bumblebee fan, I read the Bumblebee Conservation Trust’s blog post about Bombus brodmannicus last year and fell instantly in love with this bumblebee. After a while, I thought it would be a great goal for the summer holiday finding this bumblebee living high in the alps.

I wrote to Dennis Michez, the author of the blog post and he kindly delivered me an article with GPS co-ordinates of earlier observations of brodmannicus. Negotiation with my wife took five minutes and a new bumblebee goal was born!

I plotted the GPS co-ordinates where brodmannicus was found in 2012 on a paper map of the southern French Alps. Later, I contacted Prof. Pierre Rasmont from the University of Mons and he gave me several extra locations and tips (bee professors seem a kind human sub-species). The specialised bumblebee forages solely on Cerinthe minor and Cerinthe Glabra, flies at 1,000-2,000 metres and has the mad behaviour of being active early in the morning (before 07.00 AM) and late in the evening. That was not a good forecast of a slow holiday!

We left on 16 July and after a five day break at the bee walhalla Doucier in the French Jura, we travelled to the French Alps, Barcelonette (1150 asl), where we stayed with our small caravan on the nice campsite le Tampico.

From here, we did several searches for Cerinthe on Col d’Allos and Col de la Cayolle slowly driving up by car and doing multiple small walks to look for the plant.  On Col d’Allos we found a great patch (“I see a patch” was the yell of the holiday) of Cerinthe just below the top and also one just over the top, but almost every plant had finished flowering completely.

As brodmannicus was also able to forage on several other plants which I’d forgotten, I decided to focus on a large patch of Cerinthe just under the top above a large parking place which was easy to re-find and access.

At a 100×50 metres area intersected by multiple sheep paths there were multiple Cerinthe plants. I went back in the evening and thought to have found brodmannicus there. Next morning, I went up by car at 05.30am and engaged a beautiful sunrise. Several bees were foraging after seven o’clock, and I found a nest site where males were very actively nest patrolling during the morning.

Dreaming about the first brodmannicus nest ever found, I shot and shot until a dark coloured bee entered the nest making me think; What are you doing in my brodmannicus nest… After mailing a British bee professor from Col d’Allos, the answer came when I’d returned to the caravan. No brodmannicus!! Perhaps Bombus Pyreneus.

I was not very disappointed as we still had quite a lot of vacation time left and I’d made many good shots at the nest site. To observe the behaviour of the males was very fascinating.  The males had different colour patterns and were very aggressive against each other. One male entered the nest site and was kicked out immediately, dying at the nest entrance were he was grabbed by a predating insect.

After a week, we left Barcelonette for the Queyras and found a campsite in the Ristolas valley at 1650 asl. Several days later, we did a walk above Abriès, where a 1.5km footpath covered with flowers ended at the ruins of some houses at a steep southern faced slope. There, we found the patch of all patches, Cerinthe just starting to flower.

Adrenalin filled my circulation as we went back the same evening and I found one brodmannicus worker sleeping in a Cerinthe plant hanging upside down in the flowers. No other brodmannicus seen and I only shot several photo’s of this bumblebee which awoke and started foraging. I lost her after a few minutes…

Next evening I returned to the spot, as the morning was too cold and windy. The same bumblebee was sleeping in exactly the same flowers as the evening before. No other bumblebees seen and I shot multiple photos of this sole bee and left it sleeping.

The next morning at dawn, it was only 6 degrees, I went back and was at the spot at 07.30am gambling that the bees would fly later because of the low temperatures. The sleeping bee had dropped off the plant and was for dead lying on the floor under the flowers where it hung the evening before. I had no sugar with me, so warmed the bumblebee in my hand where the resurrection took place and after extensive grooming and shivering, the brodmannicus took off from my hand which gave an intense feeling of connection with this beautiful, rare species.

The next two hours, I spent patrolling the plot continuously, walking from one inflorescence to another to check for brodmannicus activity. I did see roughly five other bees, so this is what rare really means: never abundant. It was a steep slope with scattered plants so the fast bees very easy left my sight all of the time. After several more shots, my macro lens had an auto focus problem, which wasn’t the best moment for it, but I had already won the first bumblebee price so I took it and looked! The bee activity stopped at around 11am.

Altogether, it was a great experience to hunt for a specific bumblebee in the summer holiday. It brought us to where I’d never gone without this goal. The Queyras, is a pesticide free area with an extreme abundance of flowers and bees.

It is weird that it does not belong to the Outer Hebrides!

By Pieter Haringsma, Delft, the Netherlands