There's much more to Missouri's native bees than just big bumble or cuddly carpenter bees, according to entomologist Roxane Magnus.
Magnus, a volunteer at the Missouri Department of Conservation's Cape Girardeau nature center, gave a virtual presentation on some of Missouri's 425-plus native bee species Tuesday.
"Insects are my passion," she said.
As most know, bees play an essential role in pollinating both wild plants and those important in agriculture — about 80 percent of flowering plants growing in Missouri rely on bees for pollination. The honey bee is not native to the Americas; it was imported from Europe. For centuries before the honey bee's arrival, and indeed to this day, native plants relied on a dizzying array of busy native bees to reproduce.
Missouri's bees vary in size, shape and preferred food, but they have a few commonalities, according to Magnus.
"Most live about a year — they emerge in spring as adults," Magnus said. "Most of our native bees are stingless or have small stingers that can't penetrate human skin."
And most are solitary. Unlike honeybees or most bumblebees, which live in large colonies with a single fertile queen supported by workers and other specialized hive-members, these bees live singly or in small unstructured groups.
Some native bees resemble wasps and flies, and vice-versa. Magnus gave a few tips on telling them apart.
Bees generally have a chunky waist and a triangular or tear-shaped head. The majority are fuzzy, and females in most species have specialized structures for carrying pollen on their legs or abdomen. Bees have long antennae and two sets of wings, though those wings may be held close together.
Flies have a single set of wings and stubby antennae. They lack pollen-carrying structures. Syrphid flies imitate bees and wasps in their shape and patterns, but can be recognized by their tendency to hover in place.
Wasps generally have longer bodies and narrower waists than bees. They also lack pollen-carrying structures and are generally hairless.
Magnus focused her presentation on smaller and lesser-known types of bees — most people know of bumblebees and carpenter bees, but fewer are familiar with, say, long-horned bees, she opined.
"I'm going to focus on those that don't get noticed as much but are important to the natural system," she said.
You might spot the following kinds of bees visiting your garden or wild flowers. Each of the below is a broad category containing many species of bees that share some important characteristics.
Leaf-cutter and mason bees: These bees use their jaws to cut semicircles out of leaves and flower petals. They use the cuttings to line their nests, which, depending on the species, might be inside a burrow or a hollow stem. They carry pollen on the underside of their abdomens, and are important pollinators for blueberry and alfalfa farmers.
Digger and mining bees: Fuzzy and small, these bees' burrows may be spotted by scanning the ground or earthen banks small holes surrounded by mounds of soil. They drink nectar from flowers such as beardtongue, milkweed, bee-balm, dandelion and clover.
Long-horned bees: As the name suggests, these bees have long antennae protruding from their head. They also have blue-green eyes. They tend to nest under bushes and pollinate garden favorites like sunflowers, melons and squash.
Cuckoo bees: These bees resemble wasps, with few hairs, a pointy rear-end and a narrow waist. They're also brood parasites, like cuckoo birds or brown-headed cowbirds.
"They go into other native bee nests and lay eggs in there they'll destroy what's in there," Magnus explained. "They rely on other bees' hives for survival."
Squash bees: These bees only gather pollen from cucurbits — that is, cucumbers, squash, melons and pumpkins. They're most active between June and August, working from when those flowers open in the early morning to when they wilt at midday. It takes between six and 10 visits from a squash bee to fully fertilize a squash flower, Magnus said.
Sweat bees: Many Missourians have encountered small metallic-green bees eager to sip their salty sweat. Magnus acknowledged sweat bees can be annoying, but they're "very important pollinators of many native wildflowers and crops," she said. Sweat bees are diverse: some are almost as big as a honey bee, others are tiny; some are shiny, some not. They nest in burrows in clay-rich soil.
Masked bees: These bees also look like wasps, with dark hairless bodies and yellow or white patches on their faces. Their eyes are elongated and stretch along the sides of their faces. They prefer to live in convenient pre-existing holes, like hollow twigs or burrows abandoned by other bees. They visit many types of flowers, but are particularly fond of swamp milkweed.
"Hopefully next summer I get to see these guys," Magnus said.
Magnus and her husband are working to make their property more bee-friendly. They sow wildflower seeds and allow about 10 acres of their property to grow wild, rather than mowing it. They also allow dead plants to stand over the winter rather than mowing them down right away, giving bees a place to hibernate and their larvae time to develop.
They also minimize their use of pesticides — insecticides, herbicides and fungicides — many of which can be harmful to bees.
Efforts such as those are important, Magnus explained, because native bees are on the decline across the nation. Native bees are more abundant in non-farmed areas, which have a greater diversity of plant species and fewer pesticides. But the U.S.'s croplands are expanding rapidly, she said. About 77 percent of America's former grasslands, or about 5.7 million acres, are now cropland.
Magnus cited a University of Vermont study that found a 23 percent decline in bee abundance between 2008-13.
"As you drive around, look at landscapes and look at what is planted there," she suggested.
Patches of diverse wildflowers are much less common than manicured lawns or fields of crops, she said.
Native bees are also threatened by parasites and diseases, some of which have spread to native bee populations from imported honeybees.
Magnus encouraged her viewers to follow her lead in planting native plants that bloom from spring to fall, and in letting garden debris stand over the winter. The rewards are plentiful, for both humans and bees.
"It's neat to see all the wildlife, butterflies and insects we see out there," she said.