The Ridges Sanctuary

Nature Notes: Pollinators – The Heroes of the Plant World

By Libby Humphries, Environmental Educator

L-R: Leafcutter bee on butterfly weed (Asclepias tuberosa), June bug (Phyllophaga sp.), hummingbird on cardinal flower (Lobelia cardinalis).

This time of year, Door County is a-flower with golden Alexander, red columbine, and lupine (oh my!). Equally as prevalent during this time are the pollinators who depend on them to survive. This pollinator week (June 17-23), we’re celebrating the animals that are responsible for the reproduction of approximately 90% of flowering plant species across the globe. 

Pollination is the process by which pollen grains are transferred from one flower to another flower of the same species to create seeds. Even though the two flowers may look the same, their genes tell a different story; the two plants couldn’t be more different. Pollination is nature’s way of ensuring that this trend continues. If all plants were clones, or even closely related, they would have similar weaknesses to damaging insects, fungi, and bacteria. Having a diverse genetic makeup ensures that if a pathogen comes around, there will be survivors that will pass down their immunity.  

Conifers (pines, cedars, tamaracks) and broadleaved trees (aspens, birches, cottonwoods) carry out this process by releasing billions of pollen grains in hopes that the wind will carry its genetic material to another tree. Other plants—such as irises and apples—get by with a little help from their friends in the animal kingdom. When I say “friends” it’s not that these organisms are actively going out of their way to help each other; the relationship between flowering plants and animals developed over millions of years because it’s mutually beneficial. The animal receives resources from the flower, and the plant gets to reproduce.  

Who are these pollinators, you might ask? Let’s get to know them.

Bees

Perhaps our most iconic pollinators, bees are the heroes of our agricultural industry. Bees visit flowers for two reasons: pollen and nectar. For most of the 4,000 native bee species in the United States, each of these resources serves a specific purpose. Nectar is the sugar-rich food that adult bees rely on to keep buzzing around. It is the first thing that egg-laying female bees consume when they emerge in the spring, and it’s vital to their ability to reproductive ability. Protein-rich pollen is generally reserved for larvae. Solitary female bees will create a sort of lunchbox for their offspring, packing pollen into a ball and laying a single egg on it. When the egg hatches, the larva will have a ready-to-eat meal.

Since bees actively seek out pollen, they end up with a lot of it all over their bodies. This makes them some of our most valuable pollinators—helping an estimated 80% of the world’s flowering plants.

Beetles

Believe it or not, beetles are suspected to be the first insect pollinators. These beetles consumed the pollen of flowering plants during the late Jurassic period, getting individual grains stuck to their bodies and transferring them to other plants as they went about their meal.

For some beetle species, not much has changed in the last 150 million years. When modern beetles consume the petals and/or pollen of a flower, the hairs on their legs and abdomens attract pollen grains. The pollen grains inevitably fall off of the beetle when it brushes up against the various surfaces it comes into contact with, and sometimes that surface happens to be the stigma (the pollen receptacle) of another flower.

Birds

While most birds are happy to snack exclusively on seeds, insects, or small mammals to get their energy, hummingbirds need a little extra boost. Depending on the species, these zippy birds can beat their wings anywhere from 720 to 5,400 times a minute (that’s 12 to 90 times a second!). To sustain this activity level, hummingbirds rely on nectar. Their long tongues can reach the nectaries at the bottom of tube-shaped flowers, completely out of reach to some insects. To reach those nectaries, hummingbirds have to stick their beak all the way into the flower. As the hummingbird laps up the nectar, its beak brushes up against the flower’s pollen-carrying anthers, depositing pollen on it.

Bats

These mammals may be associated with vampires, but a few bat species prefer to smell the flowers. Like other flying pollinators, bats require a large amount of energy to sustain flight. Some bats (like our own little brown bat) get the energy they need from insects like caddisflies and mosquitoes. Others rely on fruit and nectar. Nectar-drinking bats have a long tongue that lets them access the hard-to-reach substance, but they lack the slender beak of a hummingbird. The result? A sometimes less-than-graceful faceplant into a flower that leaves bats resembling yellow bumble bees more than flying mammals.

While most of the plants in Door County are insect or bird-pollinated, species such as mango, aaguaro, and agave depend on bats to create the next generation of plants.

Want to learn more about our pollinators: common and uncommon? Visit our Nature Center during this week for resources, information, and the opportunity to see the pollinators that make The Ridges possible. Pick up a free Ridges Pollinator Seed Mix while you are here!

You can also go to our pollinator page for more resources and regional plant guides.