7 ms·

Bugs Matter: counting insect ‘splats’ on vehicle number plates [pdf]

106 points by Kaibeezy 5y ago

calebegg 5y ago
See also: https://en.wikipedia.org/wiki/Windshield_phenomenon https://en.wikipedia.org/wiki/Windshield_phenomenon
Gys 5y ago
A 26 page research report with a clear conclusion: > The results show that the number of insects sampled on vehicle number plates in the UK decreased by 58.5% between 2004 and 2021, and that these differences were statistically significant. A comparison of the 2004 national data with the 2019 data from Kent showed a 53.7% decrease. The greatest decreases in splat rate between 2004 and 2021 occurred in England (65%) whilst journeys in Scotland recorded a comparably smaller decrease (27.9%), with intermediate decreases in Wales (55%).
- qiskit 5y ago
  It could be evolution - insects with traits that kept them from cars were selected for. Perhaps changes to the license plates? Changes in the design of cars? Or a general decline of insect population?
  - yCombLinks 5y ago
    Yes, it could be that, but anecdotally I see significantly less bugs on cars during summers than during my childhood. The grill, windshield, etc would have dozens of lovebugs after a short drive on an early summer day. Now they're rare.
  - markburns 5y ago
    Completely anecdotal but I seem to remember flies banging their heads on windows a lot more when I was younger. Now they seem to be able to navigate their way out with comparative ease. Open a door or window and waft them in the general direction and they seem to be able to escape. I've been wondering for a few years if this was evolution.
    - sigmoid10 5y ago
      Please tell me where you live so I can move there. My flies are as dumb as ever, I can't even get them to go out the window with me actively trying to kill them. They rather take their chances with the swatter or get tangled behind the curtains.
      - markburns 5y ago
        The UK. Maybe you stress them out :)
        sigmoid10 5y ago
        From an evolutionary perspective it would seem wrong to actively go towards the source of stress when the opposite direction clearly leads to safety. But then again what do I know. Perhaps my flies are adrenaline junkies.
    - brewdad 5y ago
      I've had two birds fly into my living room window this week. I haven't even cleaned it recently. The flies may be evolving but robins have a ways to go yet.
  - yreg 5y ago
    The more aerodynamic the car is the less splats there should be, as the bugs are more likely to be carried by the flow of air around the car, correct? Still, there is no doubt that the insect population is in a massive decline.
    - throwaway0a5e 5y ago
      >The more aerodynamic the car is the less splats there should be, as the bugs are more likely to be carried by the flow of air around the car, correct? It depends on what the nature of the airflow around a specific car looks like. Bugs have a harder time than air making a "hard corner" but the mass of air stuck at a hard corner can cause other air to go around in a more graceful way and carry the bugs with them. Coefficient of drag hasn't improved much since the 90s and most of those improvements have been with regard to the vacuum behind the car so aerodynamics is probably only a contributing factor either way.
    - PheonixPharts 5y ago
      > The more aerodynamic the car is the less splats there should be, as the bugs are more likely to be carried by the flow of air around the car, correct? incorrect As I've pointed out in another comment, research has shown [0] that counter-intuitively "modern cars actually hit slightly more insects." It's a reasonable hypothesis, however what this research shows is that we would have expected to see more dead insects on cars had populations remained stable. 0. https://www.theguardian.com/environment/2020/feb/12/car-splatometer-tests-reveal-huge-decline-number-insects https://www.theguardian.com/environment/2020/feb/12/car-spla...
      - meetups323 5y ago
        Research is research, but anecdotes are anecdotes. And anecdotally, I can tell you that having done the same drive in the same conditions many times with both a Jeep Wrangler and a Toyota Prius, the Wrangler consistently has far more bugs on it, and requires multiple cleanings per leg of the journey. The Prius requires no cleanings for the duration of the trip.
  - mikestew 5y ago
    I've worn the same brand and model of motorcycle helmet (Nolan flip-up) for probably 20 years. Granted, I'm sure Nolan has made some minor changes over the years, but the aerodynamics of my massive noggin haven't changed, and I clean far, far fewer bugs off my face shield than in years past. Just my imagination? No, I have records of when I buy Honda Spray Cleaner and Polish (the pro's choice for cleaning face shields), and I don't buy as much as I used to for the same miles ridden. And old post of mine from six months ago when the topic came up, and everyone's all like "cars are more aerodynamic than they used to be" (yeah, well, my head's not), basically saying the same thing: https://news.ycombinator.com/item?id=29006969 https://news.ycombinator.com/item?id=29006969
  - titzer 4y ago
    Reasonable questions to ask. But a fairly well-known German study based on traps that catch flying insects had a 75% reduction over 27 years: [1] https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0185809 https://journals.plos.org/plosone/article?id=10.1371/journal... Just anecdotally, I see almost no bugs swarming street lights anymore, and have personally experienced the windshield phenomenon on several road trips.
- deleted 5y ago
  [deleted]
ISL 5y ago
If the (important/compelling/disturbing) science content wasn't enough, definitely open the article for terms like "Splatometer" and "Splats-per-mile".
Wistar 5y ago
It used to be—80s and early 90s—that a couple hundred mile drive down the Oregon coast would need at least one or two stops for bug splat removal. I made that drive last July and there were perhaps two splats for the entire 400-mile round trip.
- moron4hire 5y ago
  I remember being at minor league baseball games in the 90s, waiting for dark to see fireworks after the game, and getting absolutely rained on by moths falling from getting cooked in the stadium lights. The cloud of moths would be so thick it would partially obscure the lights. The girls would scream and the boys would scoop up handfuls from the ground to throw at the girls. ... Not me. Other boys. Anyway. I don't think the mosquitoes got the memo. I feel like I get more and more bites every year.
- dvh 5y ago
  '80s cars are not exactly known for their aerodynamics... _____ ___/__|__\__ [ \__|__/ ] '( )------( )=
  - Wistar 5y ago
    Last summer's trip was in a Mercedes GLK, not exactly the paragon of slipperiness.
  - Steltek 5y ago
    The majority of US cars are huge SUVs and pickup trucks. I would dare say 80's cars are more aerodynamic simply by having a smaller cross section.
    - drewzero1 5y ago
      Not necessarily. Windshields were less curved and more vertical, body panels were much less contoured, and features like sealed-beam headlights, mirrors (if equipped), and windshield wipers were more protuberant. A 1980s Mercury Grand Marquis had a drag coefficient of 0.46, while a 2018 Ram 1500 is listed at 0.357 (less is better). Obviously some 80s cars fared better, mostly compacts like my '83 SAAB 900 (3.7, not on the list below) or sports cars. I just picked the Mercury as a typical full-sized family sedan. Here's a big list, for anyone interested in some numbers: https://en.wikipedia.org/wiki/Automobile_drag_coefficient https://en.wikipedia.org/wiki/Automobile_drag_coefficient
stelonix 5y ago
Could this in any way be related to the increase of wifi, cellular or any other EM waves that got a huge boom since the early 2000s? I ask this as in, is there any research on how the EM waves we've been using the past 20-25 years interact with arthropoda in general?
- jl6 5y ago
  https://en.wikipedia.org/wiki/Decline_in_insect_populations https://en.wikipedia.org/wiki/Decline_in_insect_populations There are a lot of very plausible explanations to work through before you have to consider something exotic like EM sensitivity.
- malfist 5y ago
  Probably going to regret asking this, but is there any evidence that EM waves interact negatively in anything in the animal kingdom? Outside of literally cooking something.
  - zamadatix 4y ago
    For the "any other EM waves" portion sure, ionizing radiation damages in a very different way than heating something up. It's unrelated to things like Wi-Fi and celluar though and such non-ionizing radiation has not been found to have some other negative interaction. Extremely high power extremely low frequency radiation can also cause electrical flow but it's not been found to be problematic in humans at least. I doubt anyone has done a study on extremely low frequency radiation for arthropods in the specific time frame specified by the GP but I also doubt this portion of the EM landscape has changed significantly enough compared to before that time frame to be a relevant explanation.
omosubi 4y ago
I must say, what an ingenious way to measure insect counts. It's clever ideas like these that I come to hacker news for.
fumblebee 4y ago
Ingenious. A similar method has been employed for monitoring species’ density using roadkill as a metric [1] [1] https://www.ucf.edu/news/new-study-shows-impact-of-roadkill-on-worlds-vulnerable-animal-populations/?amp https://www.ucf.edu/news/new-study-shows-impact-of-roadkill-...
deleted 4y ago
[deleted]
um1 4y ago
I wonder if it is a matter of there simply being more cars on the road - population increase. i.e. fewer bug impact per car. Traffic? Can (higher) velocity have an effect? Off topic: same goes for “power density” in gas vs electric vehicles. What is power density in oxygen free environments like underwater or space?

106 points by Kaibeezy 5y ago

See also: https://en.wikipedia.org/wiki/Windshield_phenomenon https://en.wikipedia.org/wiki/Windshield_phenomenon

Gys 5y ago

A 26 page research report with a clear conclusion: > The results show that the number of insects sampled on vehicle number plates in the UK decreased by 58.5% between 2004 and 2021, and that these differences were statistically significant. A comparison of the 2004 national data with the 2019 data from Kent showed a 53.7% decrease. The greatest decreases in splat rate between 2004 and 2021 occurred in England (65%) whilst journeys in Scotland recorded a comparably smaller decrease (27.9%), with intermediate decreases in Wales (55%).

qiskit 5y ago
It could be evolution - insects with traits that kept them from cars were selected for. Perhaps changes to the license plates? Changes in the design of cars? Or a general decline of insect population?
- yCombLinks 5y ago
  Yes, it could be that, but anecdotally I see significantly less bugs on cars during summers than during my childhood. The grill, windshield, etc would have dozens of lovebugs after a short drive on an early summer day. Now they're rare.
- markburns 5y ago
  Completely anecdotal but I seem to remember flies banging their heads on windows a lot more when I was younger. Now they seem to be able to navigate their way out with comparative ease. Open a door or window and waft them in the general direction and they seem to be able to escape. I've been wondering for a few years if this was evolution.
  - sigmoid10 5y ago
    Please tell me where you live so I can move there. My flies are as dumb as ever, I can't even get them to go out the window with me actively trying to kill them. They rather take their chances with the swatter or get tangled behind the curtains.
    - markburns 5y ago
      The UK. Maybe you stress them out :)
      - sigmoid10 5y ago
        From an evolutionary perspective it would seem wrong to actively go towards the source of stress when the opposite direction clearly leads to safety. But then again what do I know. Perhaps my flies are adrenaline junkies.
  - brewdad 5y ago
    I've had two birds fly into my living room window this week. I haven't even cleaned it recently. The flies may be evolving but robins have a ways to go yet.
- yreg 5y ago
  The more aerodynamic the car is the less splats there should be, as the bugs are more likely to be carried by the flow of air around the car, correct? Still, there is no doubt that the insect population is in a massive decline.
  - throwaway0a5e 5y ago
    >The more aerodynamic the car is the less splats there should be, as the bugs are more likely to be carried by the flow of air around the car, correct? It depends on what the nature of the airflow around a specific car looks like. Bugs have a harder time than air making a "hard corner" but the mass of air stuck at a hard corner can cause other air to go around in a more graceful way and carry the bugs with them. Coefficient of drag hasn't improved much since the 90s and most of those improvements have been with regard to the vacuum behind the car so aerodynamics is probably only a contributing factor either way.
  - PheonixPharts 5y ago
    > The more aerodynamic the car is the less splats there should be, as the bugs are more likely to be carried by the flow of air around the car, correct? incorrect As I've pointed out in another comment, research has shown [0] that counter-intuitively "modern cars actually hit slightly more insects." It's a reasonable hypothesis, however what this research shows is that we would have expected to see more dead insects on cars had populations remained stable. 0. https://www.theguardian.com/environment/2020/feb/12/car-splatometer-tests-reveal-huge-decline-number-insects https://www.theguardian.com/environment/2020/feb/12/car-spla...
    - meetups323 5y ago
      Research is research, but anecdotes are anecdotes. And anecdotally, I can tell you that having done the same drive in the same conditions many times with both a Jeep Wrangler and a Toyota Prius, the Wrangler consistently has far more bugs on it, and requires multiple cleanings per leg of the journey. The Prius requires no cleanings for the duration of the trip.
- mikestew 5y ago
  I've worn the same brand and model of motorcycle helmet (Nolan flip-up) for probably 20 years. Granted, I'm sure Nolan has made some minor changes over the years, but the aerodynamics of my massive noggin haven't changed, and I clean far, far fewer bugs off my face shield than in years past. Just my imagination? No, I have records of when I buy Honda Spray Cleaner and Polish (the pro's choice for cleaning face shields), and I don't buy as much as I used to for the same miles ridden. And old post of mine from six months ago when the topic came up, and everyone's all like "cars are more aerodynamic than they used to be" (yeah, well, my head's not), basically saying the same thing: https://news.ycombinator.com/item?id=29006969 https://news.ycombinator.com/item?id=29006969
- titzer 4y ago
  Reasonable questions to ask. But a fairly well-known German study based on traps that catch flying insects had a 75% reduction over 27 years: [1] https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0185809 https://journals.plos.org/plosone/article?id=10.1371/journal... Just anecdotally, I see almost no bugs swarming street lights anymore, and have personally experienced the windshield phenomenon on several road trips.
deleted 5y ago
[deleted]

ISL 5y ago

If the (important/compelling/disturbing) science content wasn't enough, definitely open the article for terms like "Splatometer" and "Splats-per-mile".

Wistar 5y ago

It used to be—80s and early 90s—that a couple hundred mile drive down the Oregon coast would need at least one or two stops for bug splat removal. I made that drive last July and there were perhaps two splats for the entire 400-mile round trip.

moron4hire 5y ago
I remember being at minor league baseball games in the 90s, waiting for dark to see fireworks after the game, and getting absolutely rained on by moths falling from getting cooked in the stadium lights. The cloud of moths would be so thick it would partially obscure the lights. The girls would scream and the boys would scoop up handfuls from the ground to throw at the girls. ... Not me. Other boys. Anyway. I don't think the mosquitoes got the memo. I feel like I get more and more bites every year.
dvh 5y ago
'80s cars are not exactly known for their aerodynamics... _____ ___/__|__\__ [ \__|__/ ] '( )------( )=
- Wistar 5y ago
  Last summer's trip was in a Mercedes GLK, not exactly the paragon of slipperiness.
- Steltek 5y ago
  The majority of US cars are huge SUVs and pickup trucks. I would dare say 80's cars are more aerodynamic simply by having a smaller cross section.
  - drewzero1 5y ago
    Not necessarily. Windshields were less curved and more vertical, body panels were much less contoured, and features like sealed-beam headlights, mirrors (if equipped), and windshield wipers were more protuberant. A 1980s Mercury Grand Marquis had a drag coefficient of 0.46, while a 2018 Ram 1500 is listed at 0.357 (less is better). Obviously some 80s cars fared better, mostly compacts like my '83 SAAB 900 (3.7, not on the list below) or sports cars. I just picked the Mercury as a typical full-sized family sedan. Here's a big list, for anyone interested in some numbers: https://en.wikipedia.org/wiki/Automobile_drag_coefficient https://en.wikipedia.org/wiki/Automobile_drag_coefficient

stelonix 5y ago

Could this in any way be related to the increase of wifi, cellular or any other EM waves that got a huge boom since the early 2000s? I ask this as in, is there any research on how the EM waves we've been using the past 20-25 years interact with arthropoda in general?

jl6 5y ago
https://en.wikipedia.org/wiki/Decline_in_insect_populations https://en.wikipedia.org/wiki/Decline_in_insect_populations There are a lot of very plausible explanations to work through before you have to consider something exotic like EM sensitivity.
malfist 5y ago
Probably going to regret asking this, but is there any evidence that EM waves interact negatively in anything in the animal kingdom? Outside of literally cooking something.
- zamadatix 4y ago
  For the "any other EM waves" portion sure, ionizing radiation damages in a very different way than heating something up. It's unrelated to things like Wi-Fi and celluar though and such non-ionizing radiation has not been found to have some other negative interaction. Extremely high power extremely low frequency radiation can also cause electrical flow but it's not been found to be problematic in humans at least. I doubt anyone has done a study on extremely low frequency radiation for arthropods in the specific time frame specified by the GP but I also doubt this portion of the EM landscape has changed significantly enough compared to before that time frame to be a relevant explanation.

omosubi 4y ago

I must say, what an ingenious way to measure insect counts. It's clever ideas like these that I come to hacker news for.

fumblebee 4y ago

Ingenious. A similar method has been employed for monitoring species’ density using roadkill as a metric [1] [1] https://www.ucf.edu/news/new-study-shows-impact-of-roadkill-on-worlds-vulnerable-animal-populations/?amp https://www.ucf.edu/news/new-study-shows-impact-of-roadkill-...

deleted 4y ago

[deleted]

um1 4y ago

I wonder if it is a matter of there simply being more cars on the road - population increase. i.e. fewer bug impact per car. Traffic? Can (higher) velocity have an effect? Off topic: same goes for “power density” in gas vs electric vehicles. What is power density in oxygen free environments like underwater or space?