Bee visitors in your garden – learn to recognize them
The stereotype of bees is somewhat skewed: black and yellow stripes, they sting and make honey. When I show people the variety of bee visitors in their garden, many are surprised how a bee can look like. Distinguishing bees from wasps and hoverflies is another issue. I realized how difficult this could be to beginners during one of my first “wild bee courses” in Hohenheim. Showing a Resin Bee at a trap nest on the institute wall a participant exclaimed: “But that’s not a bee, that’s a mosquitoe!”. In broadest Swabian dialect. He was interested to learn, but this diversity in size and colour just blew his mind. To learn to distinguish the bee species in your garden the first step may be to understand that size and colour are no good features to rely on. This varies quite a lot even within species and much more between species.
Unfortunately, there is not “the one” feature to determine a bee. To distinguish them from hoverflies, it helps to remember that bees always have long antenae. Hoverflies have only very short antennae, often you can hardly see them. But hoverflies are very good in pretending to be bees. This is called “mimikry” and protects them against enemies. Especially the species mimicking bumblebees are so good at this, that I often have to take a second look. The antenna trick does not work with wasps, they have long antennae, too. To recognize bees – or any other animal group – you have to train your eye for patterns. In biology, we speak of “habitus” to describe to the appeareance. How do you recognize a bird? This may seem easy, though, also birds vary a lot in size and colour. Take a wren or a golden eagle. Both birds.
Start small – start in your garden (or park)
But back to bees. As always when learning something new, the best advice is to start small. And begin with what you have. Spend some time in your garden or a park, sit down and observe a flower. A good start now in spring would be a patch of dandelions. Very attractive to many different bees.
All these are bees, though they look very different. What they have in common? They have structures to collect pollen on their body. They “work” in a flower, they dive in it. When they leave, they usually fly to the next one. Often already stretching out that tongue to get the nectar. Compared to bees, other flower visitors seem a bit less enthusiastic to me. But I may be biased.
When you have sit there observing what is happening around your favourite flower patch, you will get an eye for bees after a while. You will notice smaller differences like: “This one has longer antennae and does not collect pollen.” It may be a male. Or you may notice that a bumblebee looks like a species you already know, but it has one yellow stripe less and does not care for pollen. This may be a cuckoo bumble bee (I will explain this in a minute). A second step is to get some books or search for good websites to learn something about the biology, and include this in your knowledge of habitus. I recommend the Flickr site and book from Steven Falk (in English) and homepage and book from Paul Westrich (in German). If I stumble over other good resources in other languages, I will tell you.
Knowing your bee visitors
If you have spent some time observing, reading and being jealous about the fabolous photos you saw, you may begin to dare to name a species. If you begin in your garden or a park, or even in the apple orchard near your home, the choices are still small enough to give you some success. Even if many species could look quite similar and a definite ID is usually possible only with the microscope. But there are several things that can help you.
- The flight time: solitary bees (check this post from Brigit Strawbridge for some more info) have defined flight times. There are spring bees like the mining bees above. There are summer bees like the Resin Bee or the Wool Carder Bee. Checking the flight time might help you deciding between two similar species. The social species, bumblebees and honey bees, will be there for the whole season.
- The flowers visited: do you find a certain bee mainly on single plant species? It may be a specialist, an “oligolectic” species. These collect pollen only form a limited range of flowers, sometimes only a single species. Again, these must be solitary, social species cannot “afford” to forage only on a single flower type, they need something to feed on during the whole season. They are “polylectic”, generalists. Also many solitary bees are (like the Red Mason Bee). You may also notice that some bees prefer “flat” open flowers (short-tongued bees) and other go for more complex and longer flowers (long-tongued bees).
- Where they collect the pollen: Most bees collect pollen on their legs. If you look thoroughly, you will notice that some have little baskets on their hind legs (honey bees and bumblebees), others collect it in long brushes of hair. There are some species that collect pollen in their crop, but most of them carry it externally. Very notable are Mason Bees, Leafcutter Bees, Wool Carder Bees and Resin Bees: they collect their pollen under their belly. They may be the best known solitary bees, because this group (Megachilidae) are the most common bee visitors in trapnests.
- Where they nest and what they use: Most bees nest in the ground, some in trapnests, some build nests with wax, some use materials like leaves, mud, little stones, resin, plant hairs etc. Some bees do not build their own nest at all. These are the cuckoo bees that use the nest of other bee species to lay their eggs. Their offspring profits from the provisions in there and hatches instead of the host. Here are the numbers for the species in Germany:
Finally, if you live in Central Europe, this little key may help you. I made it for a Visitors’ Day in my very first year in Hohenheim (1998). You may find the original key and some more information here (in German).
This key has no scientific ambition and is not complete. But it may help to get the most probable answer what bee species you are observing at your trapnests.
After all this information, the most important tip: have fun observing bees and other pollinators in your garden. That is how you will learn most.