Go out and smell the flowers

This post will be about a behavior that is seen in both bumblebees and honeybees. There are a few, and I mean a FEW papers regarding the behavior in native bees. The behavior I am speaking…I mean writing about, is scent marking.

When they go out to gather food, by visiting flowers, they must be efficient. You don’t want to be out there too long. It’s better to have a plan of attack. Think of when you have stuff to buy. You don’t want to spend too much time driving around, store to store gathering what you need. You usually try to pick stores that are close and those that have more of what you need. The bees are the same way. They don’t want to visit every single flower out there and not gather food. Why visit empty flowers. Flowers replenish their nectar when it is all taken by visitors, but it takes a while. So there is a time when the flowers are empty.  These empty flowers are not worth visiting, and it takes time to visit them. Time that could have been spent taking food from another flower.

To help them, honeybees and bumblebees scent mark flowers. What they do is just amazing…and smart. The bees will leave a scent on the flower that tells other honeybees or bumblebees, “hey, I just visited this flower and there is nothing left.” When other bees pick up on the scent mark, they avoid the flower and visit another. They also leave scent marks on flowers that have lot’s of rewards inside. This marking makes them more efficient at gathering food.

Here is a twist though. Bumblebees can eaves drop on the scents that honeybees leave, but I have not found any literature showing that honeybees can do the same to bumblebees. Those bumblebees are clever little girls.

Now, do natives do the same thing? There are a few papers. I’m talking about 3 or so, that show different species may leave marks that only each individual can pick up on. Remember, most native bees are solitary. So telling other’s that a flower is good or bad is not what they want to do. They are competing against all others. Coming up with a “my-own-scent” would be best. So much more research needs to happen to figure this out. It would be cool to figure out what they do. I have always been interested in this subject. I actually wrote a paper on how a genus of bees may be efficient at gathering food. We (R & I) figured out that they were able to smell whether a flower contained nectar or not. What we did was take some of these native bees, set them inside a small tent with an array of flowers: Flowers with nectar, Flowers minus nectar, and flowers minus nectar plus water. We added water to make sure the bees weren’t just seeing nectar inside. It’s all a decoy people. When the bees were in the tent…and they started visiting flowers, they would visit all the flowers with nectar inside and avoid the other flowers. High chance they are smelling the flowers right. To test the hypothesis even further, we took the same bees and put a non-toxic silicone to cover their antennae, which they use for smell. It would be like covering our nose. When we did this and let them visit the flowers, the bees visited all the flowers equally. They were not visiting the correct flowers. Cool huh.

Here is a picture of one of the bees with the silicone goo on their antennae…

Osmia sp.

You may think it was mean to do this to these poor girls. But you have to hear my side of the story. The only other thing we could have done was to cut their antennae off. Since we let the bees go after they were done with the experiments (the experiments were done outdoors in the mountains…completely wild bees), I did not want them to live out the rest of their lives without antennae. It’s an important organ. I wanted to do the least invasive thing. After the experiments I took the silicone off and let them fly away. I was trying to be nice about it. There you have it…this bees smells nectar. Now we just have to figure out what the other 30,000 different species of bees do.