Of Bug Zappers and Bat Houses
This all started when I stumbled across a Facebook site called “Kindness for all Living Beings”, which that day, pictured a wonderful cut away view of a brush pile deliberately left outdoors, showing the various forms of wildlife that would occupy such a pile over winter--from lungless salamanders (who live in the bottom where humidity is the highest) to bumblebees and bunnies (not together) in the middle and finally, over-wintering birds at the top.
I wanted to run the drawing on our YBYG Facebook page (which we did), but whenever we pick up something from another source like this, I always try and scroll thru other parts of the site to make sure there aren’t any posts I would regret calling attention to later.
There were not, but there was a recent post explaining (correctly) that outdoor bug zappers kill few (if any) mosquitoes, a truth that sparked a minor outrage on the site. And then the comments veered off into “put up a bat house instead”, (Which also doesn’t work.) I will deliver those batty details next week.
Anyway, I was dismayed by the number of people relying on old outdated information, and appalled by the few who actually defended the use of zappers. So here I am, sword and shield in hand, prepared to reveal the truth—and help you not get bit and/or waste your money this summer.
From the San Gabriel Valley Mosquito Control District:
{quote}: “To investigate the effectiveness of bug zappers on mosquitoes, the Department of Entomology and Applied Ecology at the University of Delaware spent 10 weeks analyzing the contents of bug zappers. Altogether, over 13,000 insects were zapped and collected.
The Results?
Of the 13,000 zapped insects, less than 0.25% were mosquitoes. 🦟
Out of 13,000 zapped insects, over 99.75% were beneficial insects (not mosquitoes!) 🐜
Read the full study here
Experts and studies from Colorado State University Extension and the American Mosquito Control Association have also concluded that bug zappers are not effective at controlling biting mosquitoes.
Doug Mahoney interviewed a wide range of University mosquito experts for an article in Wirecutter . {And I quote}: “The first thing that Jonathan Day, PhD, a medical entomologist at the University of Florida, said to us in an interview was: “I’m surprised bug zappers are even still around.”
At which point we move on to moths, which happily dive headfirst into anything even resembling a bright light, and “take over the night shift for pollination,” according to the US Forest Service. In fact, a 2018 joint study from the Universities of York, Newcastle, and Hull found that “moths may play a much broader role as plant pollinators than previously suspected.” By tracking pollen DNA, the authors of the study found that moths pollinate a wide variety of plants, including food crops such as peas and soybeans. In addition, the study showed that moths were able to carry pollen over greater distances than honeybees, which “might help to prevent inbreeding among plants.” The bottom line: We should probably lay off large-scale moth killing.
Another victim, according to Dr. Day, are parasitic wasps, which {quote} take “the brunt of the damage when it comes to bug zappers.” These are very small insects—harmless to humans—that utilize other insects (like pest caterpillars) as hosts, often laying eggs in them and killing the pest insect in the process. According to the Virginia Cooperative Extension, “These mini-wasps are very important in agriculture, attacking a wide range of insect pests that feed on important crops—and people!”
By people he means ticks, everybody’s least favorite arachnid. Beetles, flies, caterpillars, and aphids are among the other insects utilized as hosts—and ultimately killed by the wasps. In fact, the University of Maryland Extension suggests that parasitic wasps may be “the single most important biological control method gardeners have.” Not exactly the kind of insect we want to be electrocuting.
Wirecutter author Mahoney continues: “The negative sentiment toward bug zappers appears to be nearly unanimous. We found similar statements from Iowa State University (“Bug Zappers are Harmful, not Helpful”), the University of Maine (“Beware of novelty approaches to mosquito control”), and the Texas Tech University Infant Risk Center (“Don’t use bug zappers”). All of these and other sources indicate that bug zappers should be avoided at all costs.
And finally, a special treat for the faint hearted among you: (“Quick! Run away now!”)
“This is where things get weird … and a little gross”, explains Mahoney. “Another strike against bug zappers is that they electrocute bugs with such force that some insect’s parts, like hair, legs, and wings, can be blown off the body. If these aerosolized bug parts are carrying any disease, well that’s now been misted into the air. Lovely, eh?
This information is based on a study conducted in the year 2000 by Kansas State University researchers and published in the journal Current Microbiology. It tracked the {quote} “spread of bacteria and bacterial virus during electrocution of house flies.” The conclusion was that bug zappers “could play a role in the spread of infectious disease agents.”
Discussing the study, one of the authors said, “We were surprised to see so much microorganism dissemination. We thought there may be a few bacteria that got spread, but we’re finding that really significant amounts of the fly will scatter.” According to the study, bug parts can be misted a distance of almost 7 feet.”
OK—that’s all for this week. Next time out, we will go into detail about the easy and CORRECT ways to prevent or greatly limit mosquito bites this summer; no chemicals; no zappers; no fooling.
