We do a lot of research on Hummingbird Feeders and one of the most common complaints I hear and see is that many of the feeders on the market attract bees and wasps. No one wants a hummingbird feeder filled with bees or wasps instead of hummingbirds. So, how do we keep them out and away from our feeders? There are several reasons why bees and wasps are attracted to hummingbird feeders and we'll discuss those reasons and how to mitigate the challenges. Surprisingly, the ways to keep bees and wasps away are simple, but, it requires an understanding of bee and wasp behavior. Consequently, before we get started on the merits of different feeders, we'll look at bees and wasps as a species and study their niche in nature. I have found it helpful to understand a species in nature and examine "what is it and why does it do what it does?".
Bees and wasps belong to a group of insects known as Hymenoptera, Apocrita. This is a group of insects that has developed a mutually beneficial relationship with plants that flower. Flowers secrete nectar which attracts insects and insects spread the flower's pollen by visiting other flowers for more nectar. Flowers also display their color in shorter wave lengths like yellow, blue and ultraviolet on the light spectrum.. Ultraviolet is a wave length that is very visible to Hymenoptera but not to the human eye. It is theorized that the honey bee's eye sight has developed in response to the flowers they pollinate. Here is an excellent article explaining a bee's eyesight with regards to color and what they see: https://www.beeculture.com/bees-see-matters/ . Note from the article that bees do not see the colors orange, red or infrared. Wasps, apparently, see in much the same color range as bees and do not see orange, red or infrared. See: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4970366/.
Hummingbirds are also pollinators, however, they are known to see colors in the yellow, red, ultraviolet and maybe, blue light spectrum. This difference in color vision compared to Hymenoptera is important, since in nature, bees, wasps and hummingbirds would not normally be seeking or competing necessarily for the same sources of nectar.
Now, that we know what color vision bees, wasp and hummingbirds have, how do they compare? What colors do bees, wasps and hummingbirds see in common? The answer is yellow and ultraviolet. What color do hummingbirds see that bees and wasps do not? The answer is red. Knowing these facts, check to see that your feeder has only red parts and no yellow. The feeder below is a great example of the kind of feeder that is not ideal because the bees and wasps will "see" the yellow feeder ports. Once they see the yellow, the feeder now becomes an alternate food source and bees will communicate this information back to the hive..
Another consideration for hummingbird feeders is whether the nectar reservoir is above or below the feeding ports. In the feeder to the left, the nectar reservoir is above the feeding ports and relies on two components to function: gravity and a vacuum. The vacuum is what prevents the nectar from oozing out the feeder ports. This system works great and is self regulating as long as the temperature and air pressure remain constant and or the feeder is not moved by wind or a larger bird or animal. Once one of the above circumstances changes, the vacuum is lost and the nectar overflows the ports and oozes out. The oozing is what makes it easier for the bees and wasps to get at the nectar with their shorter 1/4 inch proboscis or tongue. The oozing will also cause dripping on the ground which will attract ants and ants are an additional challenge.
Pan feeders, on the other hand, do not rely on a vacuum and have the nectar reservoir below the feeder ports. These feeders are designed for the longer tongue of a hummingbird which averages about 1 and 1/2 times the length of the bill, Depending on the hummingbird, the bill averages about an inch long. Thus, a pan feeder with a depth of 1 and 1/2 to 2 and 1/2 inches is perfect. The key to this feeder is to make sure the nectar is 1/4 inch below the feeder port to deter bees and wasps.
Other considerations for both vacuum and pan feeders is the size of the feeder ports. The larger the hole, the easier it is for bees and wasps to enter and drown. Once insects are inside the reservoir and drown, the feeder is contaminated and the hummingbirds will not feed from the feeder. Larger holes will also encourage Flickers, Woodpeckers and even Bats to use the feeder. Consequently, if you want your hummingbird feeder for only hummingbirds, you'll want to opt for a feeder port size that is 1/10 of an inch or smaller. I know that sounds like a small hole, but consider that a hummingbird can get it's tongue into a hole size smaller than 5/64 of an inch!
Occasionally, you will have the correct color of feeder with the right amount and still have bees and wasps. If this happens, move the feeder to another location. Once the bees and wasps lose the location of the food source, they quickly go to find other sources of nectar. If moving the feeder doesn't work and the bees or wasps are persistent, there are several companies that manufacture "decoy" wasp nests and sell them online. Wasps are territorial by nature and will not visit or nest within the territory of other wasps. Bees will not mix with wasps as wasps have been known to kill bees. Thus, hanging a decoy wasp nest works to deter both bees and wasps.
We hope this article has given you some important behavior facts for bees and wasps and what motivates them to use hummingbird feeders. In addition to understanding bees and wasps, our goal was to help give you tools to decide what kind of feeder is best for your needs and what to look for in a hummingbird feeder. Let us know if this article has been helpful, you have questions, ideas or other challenges or even solutions. We are always open to feedback.
Until August, Happy Birding and enjoy the summer!