Showing posts with label World Bee Day. Show all posts
Showing posts with label World Bee Day. Show all posts

Wednesday, May 20, 2026

Bees Are Not (Purposeful) Pollinators

Today is World Bee Day, for celebrating our favorite pollinators. I enthusiastically support increasing awareness of bees other than honey bees, but a vague mythology exists. Here is some food for thought, remembering that one out of every three bites of food we eat we owe to the efforts of pollinators.

A tiny sweat bee, genus Lasioglossum, visits a ornamental Amaryllis flower in our Leavenworth, Kansas yard. Bees prefer native plants, though.

There is something of a persistent fairy tale, if only implied, that portrays bees as little agents of plant reproduction, flying flower to flower to effect floral fertilization, like it is their job, or out of the goodness of their tiny little hearts. Nothing could be farther from the truth.

A female mining bee, genus Andrena, pauses to rest and groom between forays for collecting pollen. Colorado Springs, Colorado.

Bees are best described as “pollen harvesters,” or even, perish the thought, “pollen predators.” Female bees actively collect pollen as food provisions for their larval offspring. This definition applies to honey bees, bumble bees, sweat bees, mining bees, mason bees, leafcutter bees, digger bees, all the bees except the kleptoparastic cuckoo bees. Cuckoo bees don’t collect pollen, but lay their eggs in the nests of other bees that do. Cuckoo bee larvae feed on the stolen pollen reserves of their hosts.

Many cuckoo bees, like this one in the genus Nomada, look more like wasps, lacking the "fuzzy" appearance we associate with bees. Colorado Springs, Colorado.

Pollination occurs as a by-product of the bee’s determined, thorough gathering of pollen; and the body form of bees that allows pollen to be shed as frequently as it is foraged. Body plan and behavior therefore make bees effective pollinators.

A male Squash Bee, Peponapis pruinosa, waits in a flower for a potential mate to visit. This bee species visits flowers in the gourd family exclusively. Colorado Springs, Colorado.

Another facet of bee behavior is that some species are oligolectic, meaning they visit only one particular genus, or even species, of flower. This greatly increases the likelihood that pollination will happen. Many bees are generalists, and will visit a variety of flowers, lowering the possibility of compatibility of bee-shed pollen with the flower receiving the bee’s next visit. This is not usually appreciable enough to be negatively significant, but it is still worth noting.

A female sweat bee, genus Halictus, has difficulty reaching pollen and nectar in an ornamental rose flower. Colorado Springs, Colorado.

Flowers and bees have coevolved to take advantage of each other, and it is an ongoing, dynamic relationship. Human interference threatens to upend that in a variety of ways. Some plant cultivars have sterile flowers, and bees therefore waste time and energy trying to “get blood out of a turnip.” Other cultivars, bred for large, complex “double bloom” flowers, result in blossoms too complicated for bees to navigate to find pollen and nectar. Lastly, cultivars may have pollen with a much lower nutritional value than that of the native plant they were derived from.

A worker female honey bee, Apis mellifera, among the first bees active in spring. El Paso County, Colorado.

Honey bees, social bees in the genus Apis that are not native to the Americas or Australia, are the unfortunate poster children for Bee Day, thanks to public familiarity through heavy marketing campaigns by the apiculture (bee keeping) industry. While absolutely vital pollinators for industrial scale agriculture, honey bees in unmanaged, feral colonies have a serious negative impact in natural ecosystems. Honey bees hog floral resources that native bee species, most of which are solitary, need to prosper.

A female Eastern Carpenter Bee, Xylocopa virginica, robs nectar from a hosta flower, throuch a slit she cut at the base of the blossom. Leavenworth, Kansas.

Back to flowers and bees for a moment. There are long- and short-tongued bees. This difference in anatomy means that many bees are restricted to visiting flowers with shallow corollas, such that they can reach the nectar reservoirs. Some larger short-tongued bees, namely large carpenter bees in the genus Xylocopa, are able to cut a slit at the bottom of deep-throated flowers, and “rob” the nectar without dusting themselves with pollen in the process of feeding. Smaller bees follow the carpenter bee, and take advantage of the holes it cuts.

The bumble bee on the left performs proper pollination of a hosta flower, while the longhorned digger bee on the right bypasses the flower's reproductive parts and uses a slit cut by a carpenter bee to rob nectar.

If it seems like the myth of the hard-working bee might be falling apart a little, then what about other pollinators like butterflies, moths, wasps, flies, beetles, hummingbirds, and bats? Well, those organisms are not even coming to flowers for pollen, with a few exceptions. They are “flower visitors” that want nectar as sugary fuel for their high metabolism. Setae (hairs), feathers, and fur will accumulate pollen, and shed it, so again, pollination can be achieved, but it is not some kind of selfless mission of the critter.

A female leafcutter bee, genus Megachile, shears a piece from a redbud leaf to use in fashioning a cell in her nest. She can do quite a bit of cosmetic damage, but the shrub will be fine. Leavenworth, Kansas.

All of this is not to say that bees are not loveable, and in need of conservation. Here are some neat facts, tips for helping bees, and resources to investigate:


  • There are over 4,000 species of bees found north of Mexico. Hotspots include the Mojave Desert, and Colorado.
  • Most native, solitary bees nest in burrows underground, so leave some bare patches of soil in your yard for them.
  • ”Bee hotels,” aka bee condos, bee blocks, are for solitary bees that nest in natural cavities in wood. Avoid commercial products, and make your own; or, better yet, leave stumps and solid wood logs in the yard that have obvious holes from beetle borings. Snip old, hollow twigs and woody stems so bees can use those upright tunnels, too.
  • Consult online gurus like Dr. Kit Prendergast (“The Bee Babette”) of Australia, and Krystle Hickman (“beesip”) of southern California, for friendly presentations on bees, and tips on how to help them.
  • Watch My Garden of a Thousand Bees, a fascinating documentary set in the United Kingdom, but applicable elsewhere in the northern hemisphere.
  • Landscape with native plants whenever and wherever you can. Be tolerant of the damage done by female leafcutter bees making their nests by cutting chunks of foliage.

A female sweat bee, genus Lasioglossum, lives up to her name and sips perspiration from my hand. Leavenworth, Kansas.

Enjoy the rest of National Bee Day, and get ready of National Pollinator Week, coming June 22-28, 2026.

Wednesday, May 22, 2019

World Bee Day....A Little "Bee"hind

World Bee Day happened the other day, May 20, and it caught me off guard. I had never heard of it, and hustled to make some social media posts for the Facebook groups I founded or administer. I will plan a bigger campaign of celebration next year, but for now....

In fairness, World Bee Day has not been in existence very long. The date honors the birthday of Anton Janša of Slovenia, a pioneer of modern beekeeping in the eighteenth century. The United Nations passed a resolution submitted by Slovenia in 2017 to so honor him. While beekeeping in the northern hemisphere applies only to honey bees in the genus Apis, the U.N. has chosen to use World Bee Day as an opportunity to acknowledge all bee species, the vast majority of which are solitary and not managed by human beings.

North American bees range from giant "large carpenter bees" like this one....

Given the plight of pollinators in general, and the threats to apiculture (beekeeping) from mites, pesticides, industrial-scale agriculture, habitat destruction, and climate....anomalies of increasing frequency, it is easy to be pessimistic and sorrowful on World Bee Day. However, there are signs of hope all around us.

....to tiny Perdita mining bees like this one.

More people are taking up apiculture as a hobby, for example. Even better, many homeowners and small-scale farmers are recognizing the importance of native bees and building simple housing for them in the shape of "bee condos." Now a small movement is building to advocate for allowing those bare patches of soil in your lawn and flowerbed to lie fallow. The overwhelming majority of solitary bees in North America nest in burrows they excavate in the ground. Sometimes many females will nest in close proximity, giving the illusion of a "hive" or a swarm. This is not the case, and unless you step on a bee in bare feet or forcibly grab one, it is not going to sting you. Different bee species prefer different textures of soil, from sandy to clayey.

Leafcutter bees, Megachile sp., using "bee block."

Among the many reasons to celebrate World Bee Day this year is the rediscovery of the world's largest bee, Wallace's Giant Resin bee, Megachile pluto, nesting in termite mounds in Indonesia. It is an important reminder that the natural world is resilient, to at least some degree, and that most species can persist even in unfavorable circumstances.

Female cactus bee, Diadasia sp., entering her burrow.

Colorado, where my wife and I live, ranks fifth in bee diversity in the USA, boasting at least 946 species from huge bumble bees to tiny mining bees in the genus Perdita. California (1,651), Arizona (1,182), New Mexico (991), and Utah (979) rank ahead of us. That makes for a lot of bee species that need conservation if we want to continue enjoying wildflowers and eating everything from blueberries to squash to almonds.

We can encourage bees by....

  • landscaping with native trees, shrubs, herbs, and flowers.
  • Erecting bee blocks as supplementary housing for solitary bees (and wasps) that normally nest in the dead trees we cut down and logs we haul off.
  • Become "weed tolerant" of plants that volunteer in our yards, as long as they are not state-listed noxious weeds. Chances are they are native or naturalized wildflowers instead.
  • Leave a few bare patches in the lawn (if you still insist on having a lawn) and flowerbeds so that ground-nesting bees have a place to call home.
  • Advocate for changes to municipal and HOA codes and rules that currently discourage eco-friendly landscaping.

It goes without saying that eliminating pesticides and other chemicals from your yard and garden will greatly benefit all life, not just on your property but elsewhere, too, as pesticides drift on the wind and flow in runoff from rain and watering.

Female sweat bee, Agapostemon sp., living up to her name.

World Bee Day is behind us this year, but no worries. You can gear up now to celebrate National Pollinator Week next month, June 17-23, 2019. Tell me how you plan(t?) to respect that designated "holiday." Maybe you need to do what I should do, which is call my governor and ask why Colorado is not yet on the map for it....

Cuckoo bee, Nomada sp., leaving (left), small carpenter bee, Ceratina sp., arriving (right).