The season for pollinators is slowly coming to an end in many places. There are fewer and fewer bees, butterflies and hoverflies around… but some species thrive in autumn. If you have a blooming ivy in your neighbourhood, take a look at the pollinators visiting it. Maybe you’ll see the ivy bee (Colletes hederae) or the ivy longhorn hoverfly (Callicera spinolae)? They are examples of pollinators with autumn peak of activity.
I’m busy identifying bees collected during my recent field trip. I just found a male Bombus semenoviellus among them. It’s an interesting species – one of a few European species colonizing recently new areas, and at the same time being at the highest risk of suffering under climate change in the future. Do these two things contradict each other? Not really. In the future, B. semenoviellus will be losing the climatically suitable areas faster than gaining it in other places.
If you feel too optimistic today, feel free to check out the atlas of climatic risk for European bumblebees. Spoiler: climate change is very bad news for most of them.
Today’s cartoon was inspired by a recent paper I co-authored. Its main character is a rare Megachile species. I had a pleasure to watch females carrying leaf pieces. Most of Megachile species in my region cut circular leaf fragments and use them to line their nests (hence their common name – leafcutter bees). If you see a plant with numerous regular holes along the leaf edges, you can tell a Megachile female was there. I remember seeing a post on social media where a lady complained that the bees cut almost all leaves of her favourite rose. I know quite a few people who would happily allow the bees take all the plants from their garden. Usually, however, leafcutter bees don’t cause any obvious damage, and live in our gardens unnoticed by most.
Mimicry is a phenomenon in which one species becomes, in the course of evolution, similar to another. One of the classical examples are bumblebee-mimic or wasp-mimic hoverflies. But how do we know that a hoverfly mimics a bee or wasp, and not the other way around?
The type of mimicry we see in hoverflies evolved to give protection against predators. The distinctive appearance says: don’t eat me, I can hurt you. The weapon of bees and wasps is their stinger. Hoverflies are harmless, and they get protection from being confused with stinging insects by predators. Therefore, bees and wasps are models, and hoverflies are mimics, not the other way around.
This post was created in collaboration with The Pollinator Academy, a great resource of knowledge about taxonomy of European bees, hoverflies and butterflies.
Some phenomena can be studied only when you can recognize individuals of the same species. For example, red mason bees often usurp each other’s nests. If you can’t tell them apart, you have little chance of knowing that the bee provisioning a nest is not the same as yesterday. Have you ever wondered how scientists tell one bee from another in their experiments?
A frequently used method is gluing tiny plastic tags on the bees’ thoraxes. The combination of colour and number is unique for every individual in the studied population. I used tags on the red mason bees (Osmia bicornis) during my PhD studies, and here you can see an example of ongoing study on the orchard mason bee (Osmia cornuta) conducted by Grupo de Investigación en Ecología de Insectos y de la Polinización, CREAF. There is also a photo of a real tagged bee!
Last week, I was observing bees in a garden. Among other plants, there were two flowers, looking more or less the same to me. One was visited by quite many bees, and the other was abandoned. After a moment, I saw a male bee zooming around it. Maybe it was a coincidence, but males of some bee species are well known for their aggressive defence of their territory. Maybe the other bees just didn’t want trouble.
Today is a special day! Best wishes to all bees and bee lovers!
Would you like to give something to non-honey bees on this occasion? You’ll probably see lots of posts featuring the managed honeybees as the only species celebrating today. Leave comments informing people about all the non-honey rest!
I’d like to show you what I drew lately. It’s not a comic but there are cartoon bees on it. Let me know if you’d like to see more such drawings. I have some on my computer, and plans for drawing more in the future.
A friend of mine has a button pin machine and I got a pin with the large carpenter bee. It goes with me everywhere on my backpack. There is a Polish common name, in addition to the scientific one.
Twisted-wing insects (Strepsiptera) are extraordinary parasites. They parasitise various other insects, bees among them. Because Strepsiptera parasitising bees belong to Stylopidae family, affected bees are called ‘stylopised’. The parasite has an extraordinary life cycle. The female spends her whole life inside the host’s abdomen, with only her head sticking out from between tergites. Male lives the same way only up to pupation, and adult males are extremely short-lived: they die after a few hours. They have one pair of fan-shaped wings.
The parasite causes extensive changes in the host’s appearance and behaviour. Stylopized bees don’t reproduce, and they look as intersexes (males acquire some female morphological traits, and vice versa), which makes them harder for entomologists to identify to the species level.
This post was published on Instagram in cooperation with The Pollinator Academy. I’m happy to be involved in this initiative. If you are interested to learn about European pollinator species, in particular bees, hoverflies and butterflies, and recognizing them, check out the PA website!
Non-honey bees 