- Nick Escobar
- Bee at Starved Rock State Park
Most folks don't know a lot about insects. Insects move fast and we have some sort of phobia. We urbanized animals have a penchant for cultivating turf grass and concrete and tend not to have that many insects around us. But the pollinator-plant connection (and sometimes dependency) is real.
I recently spent some pleasant hours speaking with local ecologist Tomasz Przybylowicz about our shared love of bumblebees. I have warmed them in the palm of my hand by breathing on them and have watched them take shelter in large cupped flowers when it rains. But Tomasz studies bee neurology and he wants to blow our minds about their minds. Before that, we both agree that folks need to get straight on two things.
All things that buzz are not bees: Bees are pollen eaters and nectar drinkers. Bees are hairy, long-antennaed, and usually chunky-bodied. They have four wings, both two fore wings and two hind wings that connect with tiny hooks called hamuli so they can work as paired units. Bees are in the order Hymenoptera along with ants and wasps. Flies, mosquitoes, and gnats are in the order Diptera, as they have two wings.
Bees and honeybees are not interchangeable: There are 4,500 bee species in North America (30,000 on this planet) and currently 150 native bee species in Chicago alone. Eighty percent of these bees are ground nesters, meaning they need undisturbed ground to build nests. The other 20 percent of bees nest in wood cavities. Some native bees are solitary and some social, semi-social, or quasi-social. Some are as tiny as mosquitoes (the bee genus Perdita) and others are large, such as carpenter bees. Honeybees are from Europe and are commercialized. They are the only bees that produce and store evaporated and regurgitated nectar, or honey.
Apparently while tiny and almost a thousand times smaller, a bumblebee brain is vastly more efficient than our own brains and can compute visual information 15 times as quickly. With each repeated tracing of a path from flower to flower, bumblebees progressively wayfind more efficiently. They navigate by the sun and landmarks from trees to swing sets. A bumblebee's working memory is eight seconds long (a point we actually are better at) and can tell when a flower has already been visited that day and the nectar thus emptied.
Bumblebees have two large compound eyes, positioned more widely apart than flies' eyes, and also three eyes on top of their head called ocelli. The compound eyes are for vision to navigate obstacles, pathways, and the ultraviolet patterns within flowers. The ocelli note directional light such as the position of the sun. The bees recognize symmetry.
Bumblebees need 18 mg of sugar a day so will forage for up to 18 hours with favorable weather conditions, and might visit 1,000 flowers during that time. They can muscle their way into somewhat-closed flowers that other pollinators can't, such as the gentians, turtlehead, monkshood, blueberries, and huckleberries. They also do buzz pollination or sonification, where they uncouple buzzing from flight muscles and vibrate to the right frequency to cause flowers' anthers to open and release pollen. Tomatoes, peppers, and eggplant are buzz pollinated. Eat a tomato, whether gown outside or in a hothouse, and thank a bumblebee.
While bumblebees are spotted early in the season, they are also some of the latest to disappear. They can fly under fairly wet conditions. They can survive at temperatures just above freezing, partly due to their fur, but also because of their ability to vibrate or "hum" to bring body temperatures up. This makes them adapt to high altitudes and high latitudes.
After the bumblebee queen emerges from hibernation in the ground in early spring, she forages for nectar from open flowers—witch-hazel, winter aconite, snowdrops, croci, willow. This first foraging flight is the most dangerous time of her life. She is weak and must find nectar and also a nesting site for her brood. Usually this is a hole of some sort: an animal burrow, an old birdhouse, or a crack in your foundation. She enters and, if the spot is suitable, makes waxen bowls to store nectar when the weather is inclement and others into which she lays ten to 15 eggs and then seals with more wax. Her first brood to emerge are the female workers who take on the foraging, defense, and brood-rearing. The queen spends the rest of her life in the dark, laying eggs until she dies in early fall and new impregnated queens fly to dig burrows to hibernate all winter.
A few weeks back, Tomasz found a very weak bumblebee. It was a queen, because she was so large and out so early in the season. He gently caught her and made a beehome for her out of parts from a honeybee hive—a large bottom board, a hive box with some residual wax stuck on its sides, a bit of comb with both pollen and honey. He covered it with a piece of acrylic sheeting, confident she had everything she needed—safety, warmth, and food to refuel herself.
This queen found a small hole in his construction and promptly left. "What do I know about making bumblebee nests?" he said.
Tomasz is developing a game called Bombus based on bumblebee economics. It's both a strategy and educational game where one starts as a queen, has to build her colony, outmaneuver predators and severe weather, develop strategies every day to find flowers full of nectar, and invest in more bees as a cost of more energy. He wants the bees to look like actual specimens and the flowers to be actual species. He insists on it being made from cardboard so people actually have to physically move the bumblebee game pieces from place to place. This makes me grin.
So here's an invitation: before this month ends, lie belly down in a meadow or an uncut weedy vacant lot and prop yourself up on your elbows and watch the air bounce with tiny flying bodies as they drink morning dew from bent grass blades and dodge each other while searching for nectar and pollen. v
For more information about native bees check out the Native Bee Awareness Initiative and Xerces Society.