Should You Feed Native Bees?
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On its surface, the practice seems quite harmless - providing our dwindling native bee populations
with a bit of supplemental food. But actually, the issue is much more complicated.
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Bees feed exclusively on sugary nectar and protein-rich pollen from flowering plants.
Our native bees require carbohydrates (sugars in nectar or honey), amino acids (protein from pollen),
lipids (fatty acids, sterols), vitamins, minerals (salts), and water. Additionally, these nutrients must be
present in the right ratio for native bees to survive and thrive.
Nectar is the native bee's natural diet and is more complex than sugar water.
Nectar is the main source of carbohydrates in the natural diet of native bees. Sugar concentration in
nectar can vary widely, from 5% to 75%, although most nectar is in the range of 25% to 40%. A native
bee uses her proboscis to suck up nectar from flowers and stores the liquid in her crop.
Nectar is sugar water, made up of sucrose and either fructose or glucose. Nectar also has protein and
salt. The ratio of sugar to water varies from flower to flower. The nectar from some flowers contains as
few as 10 calories, while others contain as much as 82 calories.
Feed native bees sugar water should only be viewed as an “emergency” source of food. In situations such as
prolonged drought or a late spring freeze that kills early blooming plants, you might consider feeding
sugar water.
That is, the last resort when natural resources simply aren’t available or aren’t sufficient. As pointed out
earlier, natural sources have beneficial nutrients sugar water lacks. For the health of all bees, wild or
otherwise, natural sources of nectar are much healthier.
Bees are opportunistic. They go for
whatever is most efficient. Providing an open supply of sugar water could, in theory, attract bees away
from the naturally occurring nectar sources.
Remember, when you put out sugar water, you will also be attracting all sorts of opportunistic insects, including
wasps and ants - sometimes in very large numbers.
So, if you want to feed bees sugar water, be sure your feeder is an appropriate color.
To attract our native bees, you need to provide a feeder that takes advantage of the bee's color vision.
Humans see light in wavelengths from approximately 390 to 750 nanometers (nm). These wavelengths
represent the spectrum of colors we can see. Bees, like many insects, see from approximately 300 to
650 nm. That means that bees can’t see the color red, but they can see in the ultraviolet spectrum
(which humans cannot).
Ultraviolet vision is especially important to bees as these ultraviolet patterns often outline
landing zones, pointing them towards the part of the plant containing nectar
and pollen.
Bees can also easily distinguish between dark and light – making them very
good at seeing edges. This helps them identify different shapes, though they can have trouble
distinguishing between similar shapes that have smooth lines – such as circles and ovals.
You Can Help Native Bees
Use caution and restraint with chemical fertilizers or pesticides.
Consider converting lawns to biodiverse landscapes that provide food for pollinators.
Provide shelter and nesting materials withstanding snags, brush piles and natural, permeable mulch.
Leave some soil bare to encourage ground-nesting bees.
A pie plate filled with stones provides a perch for insects to take a drink without falling in.
Plant a diversity of flowering plants, opting for species native to your area rather than hybrids or imports.
Choose plants that flower in early spring and late fall when other pollen sources are scarce.
Wisconsin Bee Identification Guide
Spring Wild Bees of Wisconsin
Bumble Bees of Wisconsin
Wild Native Bee Nest Boxes