# Is part of the windshield effect just that cars are more aerodynamic **URL:** \ **Category:** Factual Questions\ **Created:** [February 14, 2019, 4:07am UTC](https://boards.straightdope.com/t/is-part-of-the-windshield-effect-just-that-cars-are-more-aerodynamic/829518 "2019-02-14T04:07:41Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Wesley\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wesley_clark/32/20581_2.png) [@Wesley\_Clark](https://boards.straightdope.com/u/Wesley_Clark)\ **Post date:** [February 14, 2019, 4:07am UTC](https://boards.straightdope.com/t/is-part-of-the-windshield-effect-just-that-cars-are-more-aerodynamic/829518/1 "2019-02-14T04:07:41Z")
Insects have been disappearing, they are something like 80% less common now than they were just a few decades ago. There is something called the windshield effect, which means as recently as the 90s people remember their car windshields being full of dead bugs. Now that rarely happens. Part of that is that there are fewer insects, but someone mentioned it could be due to cars being more aerodynamic now. Instead of hitting the windshield, they fly over or around the car. Is there any proof of this? ---
**Author:** ![kk\_fusion](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kk_fusion/32/15276_2.png) [@kk\_fusion](https://boards.straightdope.com/u/kk_fusion)\ **Post date:** [February 14, 2019, 7:48am UTC](https://boards.straightdope.com/t/is-part-of-the-windshield-effect-just-that-cars-are-more-aerodynamic/829518/2 "2019-02-14T07:48:07Z")
[Josef Settele](https://www.ufz.de/index.php?en=38572) made experiments with less aerodynamic off-road vehicles and found that they still gather a considerable amount of insects. If you want to dig through his publications, it’s probably in there somewhere. ---
**Author:** ![Filbert](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/filbert/32/3433_2.png) [@Filbert](https://boards.straightdope.com/u/Filbert)\ **Post date:** [February 14, 2019, 9:03pm UTC](https://boards.straightdope.com/t/is-part-of-the-windshield-effect-just-that-cars-are-more-aerodynamic/829518/3 "2019-02-14T21:03:21Z")
It’s probably _part_ of the effect, but people with vintage vehicles have also reported a drastic reduction in dead bugs, plus the reduction has also been shown by [other](https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0185809&_ga=2.266632718.1476661257.1527292800-1633289002.1527292800) insect sampling methods. The car hits are more widely reported because that’s something people can see for themselves, rather than it being the major data source. ---
**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\ **Post date:** [February 14, 2019, 9:59pm UTC](https://boards.straightdope.com/t/is-part-of-the-windshield-effect-just-that-cars-are-more-aerodynamic/829518/4 "2019-02-14T21:59:19Z")
Or perhaps insects have evolved to become smart enough to stay away from roads 😉 ---
**Author:** ![tampora](https://avatars.discourse-cdn.com/v4/letter/t/9de0a6/32.png) [@tampora](https://boards.straightdope.com/u/tampora)\ **Post date:** [February 15, 2019, 12:01am UTC](https://boards.straightdope.com/t/is-part-of-the-windshield-effect-just-that-cars-are-more-aerodynamic/829518/5 "2019-02-15T00:01:28Z")
> [@Wesley\_Clark](#): > > Insects have been disappearing, they are something like 80% less common now than they were just a few decades ago. Source? ---
**Author:** ![Shagunathor](https://avatars.discourse-cdn.com/v4/letter/s/e47c2d/32.png) [@Shagunathor](https://boards.straightdope.com/u/Shagunathor)\ **Post date:** [February 15, 2019, 2:05am UTC](https://boards.straightdope.com/t/is-part-of-the-windshield-effect-just-that-cars-are-more-aerodynamic/829518/6 "2019-02-15T02:05:37Z")
In Germany: > **[More than 75 percent decline over 27 years in total flying insect biomass in...](https://journals.plos.org/plosone/article?id=10.1371%2Fjournal.pone.0185809)** > > Global declines in insects have sparked wide interest among scientists, politicians, and the general public. Loss of insect diversity and abundance is expected to provoke cascading effects on food webs and to jeopardize ecosystem services. Our... “Our analysis estimates a seasonal decline of 76%, and mid-summer decline of 82% in flying insect biomass over the 27 years of study.” There are links to this and other papers in this pop-science article: > **[As Insect Populations Decline, Scientists Are Trying to Understand Why](https://www.scientificamerican.com/article/as-insect-populations-decline-scientists-are-trying-to-understand-why/)** > > The real story behind reports of an “insect Armageddon” is more nuanced—but probably just as unsettling ---
**Author:** ![Ruken](https://avatars.discourse-cdn.com/v4/letter/r/f475e1/32.png) [@Ruken](https://boards.straightdope.com/u/Ruken)\ **Post date:** [February 15, 2019, 2:44am UTC](https://boards.straightdope.com/t/is-part-of-the-windshield-effect-just-that-cars-are-more-aerodynamic/829518/7 "2019-02-15T02:44:40Z")
I was at a natural gas vehicles conference a few years ago and a guy who had converted class 8 trucks to NGVs said he tested their aerodynamics with a “redneck wind tunnel”, which meant he drove it and counted bug splatters. So there are bugs to splatter if you build it to splatter. But I think insect surveys are conducted other ways. I vaguely recall something about netting tall grass back when I worked for an environmental engineer.