Q: I have managed to attract a colony of Ruby-Throated Hummingbirds to my inner-city patio for the past three summers, but I'm having trouble with two predators: Aggressive wasps that compete at the feeders and occasionally try and sting the birds; and a garden friend turned enemy, the Praying Mantis, which I understand are wonderful to have in the garden, and as you know are a protected insect species here—but they are also one of the top predators of hummingbirds. Can you please give me some advice as to how to deal with these problems?
---Wilma in West Philadelphia
A. Let's begin with the praying mantis, that so-called 'protected' and 'beneficial' insect….
Mantises are insects, but they are neither protected in the United States nor technically a beneficial. Although commonly felt to be true, the stories about it being illegal to harm a mantis are just that—stories. And true beneficial insects (like ladybugs and lacewings) only prey on pests. Mantises, like spiders, are predators that eat pest insects and good insects like pollinators. And when they grow to full adulthood, move on to larger prey—like small rodents, birds and lizards.
Now—I am NOT suggesting that anyone kill or harm a mantis. They are amazing insects just doing what comes naturally. But a little research has led me to some helpful hints on maybe making their job harder.
First, search the property for their egg masses, especially in the Fall—they're very distinctive. (Lots of images are available online.) Prune off the branch or whatever plant part any egg sacs you find are attached to and relocate them to the crook of a tree about a mile away. You don't want to move them to another state, which would be wrong—just to another neighborhood.
Second, some mantises can fly, but many can't. So make sure that the feeders are hanging from shepherd's hooks positioned a good distance away from any plants, and grease the poles so that they're difficult to climb. But first, paint the poles red.
This will do two things. First, it might attract even more hummingbirds. They love the color red and every part of a hummingbird feeder should be red. But it could also really help the birds. Mantises are 'ambush hunters' that will sit still for a long time to grab a meal, and they can change their color somewhat to blend in with their surroundings and become even harder to see. But I don't think American mantises can become red; so they would be highly visible to both the hummingbirds and their dedicated human protectors.
(I say "American mantises" because Wiki tells me that some tropical species are naturally pinkish-red or can become that color to hunt while perched on orchids. And my use of the term "American" is insect shorthand, as a lot of "our" mantises were imported from other countries for pest control and went native—which may account for differences like why some can fly and some can't.)
OK; now the stinging wasp threat.
Yellowjackets, hornets and bees are all well-documented "pests" at hummingbird feeders, as are ants and many other creatures—you can't put out sugar in the summer and not expect to attract a wide range of things with a sweet tooth. The first line of defense is to buy feeders that have what are called "bee guards"—feeding ports that are difficult for flying insects to use.
Experts also advise wiping down the feeder's holes daily to clean up spills that can defeat the purpose of the guards. It turns out that hummingbirds actually use their little tongues to lap up nectar and sugar water, and they can be pretty sloppy eaters.
And I would also put out a lot of yellowjacket and hornet traps; you can make your own or buy them commercially. Bait them with stinky overripe fruit. I catch the most yellowjackets—and lots of nuisance flies—with rotten peaches in my traps. (Traps sold for nuisance flies work just as well for yellowjackets and wasps; the designs are pretty much interchangeable.)
Now—I also mentioned ants—what about them?
The greased pole may help prevent their climbing up to the feeder; but ants are not any kind of threat to the birds; and they're potentially more food for them. We tend to think of hummers as only nectar feeders, but they eat a lot of small insects as well. And these little birds need a lot of food; Ruby Throats—the only hummingbird you're likely to see in the Eastern US and Canada—only weigh a few grams each and have to feed almost constantly to fuel their intense energy levels…
And, no I did NOT mean to say "ounces" instead of grams; these are almost impossibly tiny creatures. Even the so-called "Giant Hummingbird" of South America tops out at around 20 grams, which is about two-thirds of an ounce. And, as our listener has discovered, that small size makes them as vulnerable as they are cute.