There are many different types of pollinators in the world, including flies, beetles, butterflies, birds, and bats. When it comes to crop pollination, though, bees tend to be the most efficient -and thus the most economically important. A single species of bee, the honey bee, is used to pollinate more than 90% of dependent crops. In recent years honey bees have been struggling with stressors like Colony Collapse Disorder, pathogen spread, and pesticide exposure. As a result, there has been a wave of awareness and interest in wild bees. North America has more than 3,600 species of wild bees, many of which are solitary and soil-nesting. These bees can enhance or even surpass the crop pollination provided by honey bees. Unfortunately, wild bee populations are at risk as a result of habitat loss and agricultural intensification. We can preserve these bees by maintaining foraging and nesting habitat, as well as using pollinator-mindful farm management practices. Several bee families that can be found in Wisconsin are listed below.
Cuckoo, Carpenter, Digger, Bumble, and Honey Bees (Apidae)
Honey bees (Apis mellifera)This species is a native of the Old World, where they have been domesticated for thousands of years. After being introduced to North America, honey bees have become a very important crop pollinator. These social bees live in hives that often contain thousands of individuals.
Bumble bees (Bombus species)These large, furry bees are superior gatherers of pollen and can forage at cold temperatures. They are the preferred pollinator of tomatoes due to their ability to “buzz pollinate,” which releases pollen from flowers by vibrating them.
Squash bees (Peponapis and Xenoglossa species)Squash bees are specialists that exclusively pollinate plants in the cucurbit family (cucumbers, squash, and melons). Squash bees are active before sunrise visiting these early-blooming flowers. In the afternoon, when flowers close, squash bees can often be found hiding inside.
Mining bees (Andrenidae)The Andrenidae family contains more than 1,000 bee species that can be found in the United States. These include mining bees, which excavate underground nests for their young and provision them with balls of nectar and pollen.
Plasterer and Masked Bees (Colletidae)This family includes cellophane bees, named for the plastic-like substance they secrete to line their nests . Some colletid bees carry pollen internally in a crop instead of using pollen-gathering hairs on the legs or abdomen.
Sweat Bees (Halictidae)This is a large, diverse family of bees sometimes referred to as “sweat bees.” Most are solitary, ground-nesting species but others nest in dead wood, hollow twigs, or in semi-social nest aggregations.The members of this family -which include the Lasioglossum, Agapostemon, and Halictus genera- are the most commonly found wild bees in many different vegetable crops in Wisconsin.
Leaf-cutter and Mason Bees (Megachilidae)The family Megachilidae includes leafcutter bees and mason bees. They can be identified by their large, powerful mouthparts (which they use to cut up plant material for lining their nests) and by the pollen carrying hairs that are present on the lower surface of the abdomen rather than on the hind legs.
MelittidaeThe melittids are one of the rarest bee families, containing less than 50 North American species. Many of these bees are specialists, such as Macropis species that specialize in collecting plant oils.
- UW-Madison Insect Diagnostic Lab’s Bee Identification Guide
- Xerces Society: Pollinator conservation resources: Great Lakes region
- USDA Forest Service: Bee basics: An introduction to our native bees
- Purdue Extension fact sheet: Protecting honey bees from pesticides
- Bug Guide citizen science: Aculeata – ants, bees, and stinging wasps
- Discover Life bee identification guide: Bee genera