Decline in insect populations

[Unaffiliated]

Doing license plate splat research in the US would be problematic as 20 states issue only rear plates.  Hmmm, no bugs in Pennsylvania but lots of 'em in neighboring Ohio ...

An aside, in 1979 I found myself walking late at night on a rural road in eastern Uganda with others who had been in the Toyota Land Rover (matatu "taxi") before an erosion rut across the road prevented it from going father.  It was pitch dark but there were lots of fireflies around so staying on the road was easy. (It was mostly in good repair - there may have been two 'difficult' spots.)  After an hour or so we crested a hill and below us was a grass/shrubbery-covered (treeless) plain with billions of fireflies - everywhere except for where the road winded down the hill and into the distance.  Quite spectacular!  The "lots of fireflies" I'd seen in the roadway were as nothing compared with the density over the vegetation, once I had a from-above view.

(Yes, the next day I heard some machine gun fire in the distance - probably some rogue Ugandan soldiers [post-Tanzanian occupation] killing something to eat.)

Maybe porch light data would be more accessible to more people and have fewer inherent variables

[trm1958]

In 1967 my family drove to Niagara Falls from Cleveland area.
Windshield covered with bug splatters.
In recent years my cousin took me on a trip across state.
Nary a bug splatter.
EDIT: that was Expo67, Niagara Falls was 1966…sorry.

[vox_mundi]

Australasia's Hidden Pollination Crisis Could Threaten Biodiversity and Food Security
https://phys.org/news/2023-10-australasia-hidden-pollination-crisis-threaten.html



Australasia has likely overlooked a pollination crisis, according to new research published today in the journal Ecology and Evolution. The research, led by Macquarie University, also underscores a pressing need for intervention to avoid biodiversity loss and long-term food insecurity in the region.

The authors analyzed thousands of research papers on human-induced pollinator decline globally, and found that despite only a tiny portion mentioning Australasia, the causes of pollinator decline in the northern hemisphere were mirrored in this region.

despite little research into pollinator shortages in Australasia, Professor Pyke's team has found serious environmental threats to local pollinators that suggest Australasia's own pollination crisis has gone largely unnoticed.

"The same environmental threats to plants and their pollinators are happening in this region—but we haven't been monitoring their impact," he says.

A pollination crisis is the decline in abundance—including to the point of extinction—of animals that act as pollinators and of the plants they pollinate.

"This is not a trivial issue," says Professor Pyke. "In Australia, we estimate 15,000 animal species act as plant pollinators. Declines in these pollinator species will cascade through to the estimated 20,000 species of flowering plants in Australia that rely on or benefit from animal pollination to reproduce.

"This includes many food plants such as most fruits and many vegetables, ranging from tomatoes and beans to coffee, strawberries, canola and even cacao—essential for chocolate, which rely partially or totally on animal pollination," he adds.

... Study co-author Dr. Kit Prendergast, adjunct researcher at Curtin University, says that neglecting to conserve local indigenous pollinators exacerbates the pollination crisis. The introduced European honey bee has spread throughout Australia, playing a key role in pollination of some crops, but competes with native bees and other pollinators and can disrupt pollination systems.

"There are currently 1,660 native bee species which are described, and hundreds more that remain undescribed. The investment into these bees is vastly overshadowed by the investment into the introduced honey bee," Dr. Prendergast says.

Pollination crisis Down-Under—Has Australasia dodged the bullet?, Ecology and Evolution (2023)
https://onlinelibrary.wiley.com/doi/10.1002/ece3.10639

[kassy]

Climate change warning as insects migrate north

Wildlife surveys carried out by ecologists over the last eight years have found that insects are migrating north because of climate change.

At Bath City Farm, 1,125 species have been recorded between Twerton and Southdown with 30 of those being new varieties.

Results from the survey show that some of the recorded species were a rarity on the south coast a generation ago, but have now become common in the north of Somerset.

Mike Williams an ecologist and Trustee said: "Insects are important indicator species that help ecologists understand the realities of a changing climate on our natural world."

Three years ago, the distinctive Wasp Spider was recorded for the first time at the site; now it is a common occurrence.

Mr Williams said: "In the 1990s I only ever saw the Wasp Spider on the south coast of England, in Dorset.

"I would never have imagined then that one day they would be found as far north as Bath."

Butterfly populations were also affected due to the dry spring and wet summer.

...

The lack of frost has a negative effect on plants too.

The Yellow Rattle has suffered as the change in global temperature has affected its life cycle.

The warm temperatures mean that it struggles to germinate when it comes into season.

https://www.bbc.com/news/articles/c72v8z9kwdko

[SeanAU]

this 4 years old now, I was thinking how I never see them or other beetles like them anymore. Bogon moths have also disappeared from east Australia ... they were in their billions, would turn windshields yellow with dead moths driving at night, especially during winter.... and would flood street lights in swarms .... all pretty much gone. cicaders too, even grasshoppers are rare where I live now.

anyway ... it's more than just co2 and temps, its humans doing this too. Its all so terribly sad.

When was the last time you saw a Christmas beetle?

They used to be a mainstay of the festive season, but in recent years Christmas beetles haven’t been showing up to south-east Queensland barbeques.

Many locals will have memories of the iridescent beetles showing up in great numbers at outdoor gatherings in the past, but anecdotal evidence suggests that is no longer the case.




‘Christmas beetle’ is the name given to around 35 species of scarab beetles, with the most common in Australia being Anoplognathus pallidicollis.

They come in a range of iridescent colours including brown, yellow or even pink, which combined with their appearance during the summer months led to their common name.

A straw poll (see article) of Brisbane Times readers found over half of those surveyed either had not seen one of the beetles in the last six months, or could not remember the last time they had seen one.

Just 8 per cent said they had seen a Christmas beetle in the last month, while 6 per cent said they had seen one in the last week.

University of Queensland entomologist Myron Zalucki said it was not surprising to see Christmas beetle numbers appearing to decline because their natural habitat was slowly disappearing from the region.

“The immature stage of Christmas beetles feed on native grass, and the area of grassland around Brisbane - it was once surrounded by dairy farms for example - they’ve now gone and it’s suburbia,” Professor Zaluki said.

“So not surprisingly Christmas beetles are now rarer in Brisbane.

“Have Christmas beetles disappeared altogether? No, of course not. But if there’s a species of Christmas beetle which lived only around Brisbane and we’ve destroyed its habitat, then that species has probably disappeared.”


While some might celebrate a festive season free of what many consider a pest despite their pretty appearance, the apparent decline in Christmas beetle numbers comes amid reports of declining insect populations worldwide.

Some researchers are now warning the loss of some insect species could have unpredictable effects on the overall ecosystem, with insects responsible for the pollination of many plants.

The problem, Professor Zaluki said, was that there just was not any data being regularly and reliably gathered concerning insect populations.

“There’s no long-term monitoring data that is of any use,” he said.

“We did have traps being run in certain areas but they were mostly in agricultural areas and they were looking for pests, and most of those have been turned off because there isn’t any money for monitoring.

Insects 'Disappearing everywhere': The great extinction happening under our noses

“If you’re interested in conservation then there’s even less money, so we have no data.

=================

PS there was a second part to this - it's about how the loss of insects is already reducing bird populations .... they are under attack from all directions, droughts, floods, bush fires, habitat, nesting places, their feed reduction, heat waves .... it's a real mess.

[kassy]

Common insect species are suffering the biggest losses

Declines in insect numbers are largely driven by losses of more abundant species

Insect decline is being driven by losses among the locally more common species, according to a new study published in Nature. Led by researchers at the German Centre for Integrative Biodiversity Research (iDiv) and the Martin Luther University Halle-Wittenberg (MLU), the meta-analysis of 923 locations around the world notes two significant trends: 1) the species with the most individuals (the highest abundance) are disproportionately decreasing in number, and 2) no other species have increased to the high numbers previously seen. This likely explains the frequent observation that there are fewer insects around now than ten, twenty, or thirty years ago.

Researchers at iDiv looked at long-term trends of land-based insects, such as beetles, moths, and grasshoppers, and found that decreases in the number of the formerly most common species have contributed most to local insect declines.

Common or abundant insect species are those species that are locally found in the highest numbers, but which species these are differ among locations.

The study's findings challenge the idea that changes in insect biodiversity result from rarer species disappearing.

The study follows the recent sounding of alarm bells about insect loss, as researchers note dramatic declines in the total number of insects in many parts of the world.

However, little is known about the general trends among locally rare and abundant species over long periods.

"It was obvious this needed exploring," says Roel van Klink, lead author of the study and senior scientist at iDiv and MLU.

"We had to know whether observations about declines in total abundances of insects differed among common and rare species, and how this translated into changes in the overall insect diversity."

More common species are losing out

Van Klink and colleagues set out to better understand trends in insect numbers by diving into past studies.

They compiled a database on insect communities using data collected over periods between 9 and 64 years from 106 studies.

For example, one Dutch study on ground beetles was started in 1959 and continues today.

With this updated database, the researchers confirmed that despite variation among the data, on the whole, land-based insects from these long-term surveys are declining by 1.5% each year.

To better understand this pattern, they compared the trends of species in different abundance categories and found that species that were the most abundant at the start of the time series showed the strongest average decline -- around 8% annually -- while rarer species declined less.

Importantly, the losses of previously dominant species were not compensated for by rises in other species, which has far-reaching implications: Abundant species are a staple food for birds and other insect-eating animals, making them essential for ecosystems.

"Food webs must already be rewiring substantially in response to the decline of the most common species," explains van Klink.

"These species are super important for all kinds of other organisms and for the overall functioning of the ecosystem."

Winners and Losers

The analysis clearly shows that the formerly abundant species are consistently losing the most individuals compared to the less abundant insect species.

However, less abundant and rare species are also taking losses, driving declines in local species numbers.

The study found a modest decrease in the overall number of species of just under 0.3% annually.

This decline indicates that in addition to significant losses of common species, some rare species are going locally extinct.

Coming out on top are new arrivals who managed to successfully establish themselves.

Most of these new arrivals stay locally rare and replace other formerly rare insects, but occasionally they become very abundant.

The invasive Asian Ladybeetle (Harmonia axyridis), which is now common throughout Europe, the Americas and South Africa, is one such example.

According to the paper's authors, further research is necessary to determine the underlying causes of these trends.

Although this study did not explicitly investigate possible causes, the declines are likely linked to recent human-related impacts, such as climate change and urbanisation, which are considered major drivers of biodiversity loss.

"Insects seem to be taking a heavier hit than many other species as humans continue to dominate the planet," explains Professor Jonathan Chase, senior author of the study and professor at iDiv and MLU.

"Other studies, including those our team has worked on, have not found such diversity declines at local scales from many other groups of animals and plants."

While the study's results are striking, these trends are strongly biased to data on insect communities in Europe and North America. As such, they should not be interpreted as a global phenomenon. Chase adds: "The patterns we observed might be a best-case scenario for quantifying the real impact of people on insects," referring to what scientists have called the lifeboat effect. "These declines were observed in long-term data from areas that have remained largely intact, sort of like a lifeboat, rather than in areas where massive conversion of natural areas into human-dominated landscapes has occurred, such as malls and parking lots."

https://www.sciencedaily.com/releases/2023/12/231221012747.htm

[vox_mundi]

Why Are Bees Making Less Honey? Study Reveals Clues From Five Decades of Data
https://phys.org/news/2024-01-bees-honey-reveals-clues-decades.html

Honey yields in the U.S. have been declining since the 1990s, with honey producers and scientists unsure why, but a new study by Penn State researchers has uncovered clues in the mystery of the missing honey.

The study, recently published in the journal Environmental Research Letters, found that changes in honey yields over time were connected to herbicide application and land use, such as fewer land conservation programs that support pollinators. Annual weather anomalies also contributed to changes in yields.

Overall, researchers found that climate conditions and soil productivity—the ability of soil to support crops based on its physical, chemical and biological properties—were some of the most important factors in estimating honey yields. States in both warm and cool regions produced higher honey yields when they had productive soils.

The eco-regional soil and climate conditions set the baseline levels of honey production, while changes in land use, herbicide use and weather influenced how much is produced in a given year, the researchers summarized.

According to Quinlan, climate became increasingly tied to honey yields in the data after 1992.

The researchers also found that decreases in soybean land and increases in Conservation Reserve Program land, a national conservation program that has been shown to support pollinators, both resulted in positive effects on honey yields.

To learn more about the land use, floral resources and weather in specific areas, visit the Beescape tool on the Center for Pollinator Research website.

Beescape tool: https://pollinators.psu.edu/bee-health/beescape

Gabriela M Quinlan et al, Examining spatial and temporal drivers of pollinator nutritional resources: evidence from five decades of honey bee colony productivity data, Environmental Research Letters (2023)
https://iopscience.iop.org/article/10.1088/1748-9326/acff0c

[Human Habitat Index]

http://www.electricalpollution.com/documents/MassiveInsectDeclineKordas2022.pdf

80% decline in insect population in Samos after 5G installed.

[morganism]

Just saw an article bout how insects are attracted to lighting. They were blinded by the artificial lights, and try to align their dorsal (top) of their body to the light, getting trapped in loops.
They typically try to align to the night sky, which is typically the brightest thing around, especially in short wave. There was specific sensory organs for that?

found it))

Why flying insects gather at artificial light

Explanations of why nocturnal insects fly erratically around fires and lamps have included theories of “lunar navigation” and “escape to the light”. However, without three-dimensional flight data to test them rigorously, the cause for this odd behaviour has remained unsolved. We employed high-resolution motion capture in the laboratory and stereo-videography in the field to reconstruct the 3D kinematics of insect flights around artificial lights. Contrary to the expectation of attraction, insects do not steer directly toward the light. Instead, insects turn their dorsum toward the light, generating flight bouts perpendicular to the source. Under natural sky light, tilting the dorsum towards the brightest visual hemisphere helps maintain proper flight attitude and control. Near artificial sources, however, this highly conserved dorsal-light-response can produce continuous steering around the light and trap an insect. Our guidance model demonstrates that this dorsal tilting is sufficient to create the seemingly erratic flight paths of insects near lights and is the most plausible model for why flying insects gather at artificial lights.

https://www.nature.com/articles/s41467-024-44785-3

[vox_mundi]

The Number of Monarch Butterflies at Their Mexico Wintering Sites Has Plummeted This Year
https://phys.org/news/2024-02-monarch-butterflies-mexico-wintering-sites.html



The number of monarch butterflies at their wintering areas in Mexico dropped by 59% this year to the second lowest level since record keeping began, experts said Wednesday, blaming heat, drought and loss of habitat.

Mexico's Commission for National Protected Areas said the butterflies covered an area equivalent to 2.2 acres (0.9 hectares), down from 5.4 acres (2.21 hectares) last year.

The lowest level was in 2013 at 1.65 acres (0.67 hectares).

Experts said heat and drought appeared to be the main culprits in this year's drought.

"It has a lot to do with climate change," said Gloria Tavera, the commission's conservation director.

Experts noted there were almost no butterflies at some traditional wintering grounds, because the monarchs appeared to have moved to higher, cooler mountain tops nearby. About two-thirds of the butterflies counted this year were found outside the traditional reserves.

"The monarchs looked for other sites ... they are looking for lower temperatures," Tavera said. Because some of the newer wintering sites aren't included in the population count, there may have been more monarchs this year than the numbers suggest.

But the number of a smaller population, the western monarch butterflies that overwinter in California, has dropped, too.

[kassy]

Wildflower Scent Degraded by Nitrate Radicals in Polluted Air


This is not a dystopian scenario, but a reality that is unfolding before our eyes. A recent study spearheaded by the University of Washington unveils a sinister, invisible force at play in our environment.

Nitrate radicals (NO3) in the air, primarily produced by emissions from cars, power plants, and other sources, are wreaking havoc on an unexpected front - the intricate dance between nocturnal pollinators and flowers.

...

These scent chemicals are especially important for flowers that bloom at night, when visual cues are limited. Nocturnal pollinators, such as moths, rely on these scents to locate flowers under the cover of darkness.

They use their antennae, which are equipped with olfactory receptors, to detect and follow the scent trails.

However, these scent chemicals are not stable; they can react with other molecules in the air and degrade over time and distance.

This degradation is not just a matter of a less fragrant night air; it has dire consequences for the pollinators that rely on these scents to find their floral partners.

The researchers discovered that one of the main culprits behind this degradation is NO3, a highly reactive molecule that is formed when nitrogen oxides (NOx) react with ozone (O3) in the atmosphere.

NOx are emitted from various human activities, such as burning fossil fuels, while O3 is produced by the action of sunlight on oxygen. NO3 is most abundant at night, when O3 levels are high and NOx levels are low.

...

https://www.natureworldnews.com/articles/60594/20240209/wildflower-scent-degraded-nitrate-radicals-polluted-air.htm

[vox_mundi]

Research Finds Honey Bees May Be At Risk for Colony Collapse From Longer, Warmer Fall Seasons
https://phys.org/news/2024-03-honey-bees-colony-collapse-longer.html

Flying shortens the lives of bees, and worker honey bees will fly to find flowers whenever the weather is right, regardless of how much honey is already in the hive. Using climate and bee population models, researchers found that increasingly long autumns with good flying weather for bees raises the likelihood of colony collapse in the spring.

The study, published in Scientific Reports, focused on the Pacific Northwest but holds implications for hives across the U.S. The researchers also modeled a promising mitigation: putting colonies into indoor cold storage, so honey bees will cluster in their hive before too many workers wear out.

For this study, researchers ran simulations through a honey bee population dynamics model using climate projections for 2050 and the end of the century at 2100. They found that honey bee colonies that spend the winter outside in many areas of the Pacific Northwest would likely experience spring colony collapses in both the near- and long-term scenarios. This also occurred under a simulation where climate change continued as it is progressing now and one where greenhouse gas emissions were reduced in the near future.

Worker honey bees will forage for food whenever temperatures rise above about 50° Fahrenheit. When it gets colder, they cluster in the hive, huddling with other bees, eating honey reserves and shivering, which helps keep the bees warm.

In the spring, the adult worker bees start flying again. That means they also start dying. If too many older worker bees die before their replacements emerge ready to forage, the whole colony can collapse. Scientists have estimated this happens when there are fewer than 5,000 to 9,000 adult bees in the hive.

This study found that colonies wintering outside in colder areas like Omak in the far north of Washington state might still do all right under climate change. But for honey bee colonies in many other places, like Richland, Washington near the border of Oregon, staying outside in the winter would mean the spring hive population would plummet to fewer than 9,000 adults by 2050 and less than 5,000 by the end of the century.

"Our simulations are showing that even if there is no nutritional stress, no pathogens, no pesticides—just the conditions in fall and winter are enough to compromise the age structure of a colony. So when the hive comes out of winter, the bees are dying faster than they're being born," said co-author Gloria DeGrandi-Hoffman, a research leader at the U.S. Department of Agriculture's Carl Hayden Bee Research Center.

Warmer autumns and winters could reduce honey bee overwintering survival with potential risks for pollination services, Scientific Reports (2024)
https://www.nature.com/articles/s41598-024-55327-8

[vox_mundi]

Moths Big and Small Are Vanishing From Southern US Cities
https://phys.org/news/2024-03-moths-big-small-southern-cities.html

In a new study, researchers presented the results of a year-long survey in which they monitored the abundance of adult and larval moths in an urban, sub-tropical environment. It's the first time researchers have analyzed multiple life stages to assess the severity of ongoing insect declines. It's also one of only a few studies that have tackled the problem in lower latitudes, where extreme temperatures are pushing animals to their limit.

The results showed a strong pattern of decline among moths of all sizes and life stages from rural to urban areas.

A closer look at the macromoths alone revealed that, contrary to expectations, larger macromoths fared worse than than those that were smaller. This runs counter to a previous study conducted in Belgium, which showed the opposite pattern.

Belitz suspects the difference in average temperature between temperate Europe and subtropical Florida is the culprit. Large moths must expend more energy to keep cool than those that are small. Similar patterns have been seen in other insects, Belitz said.

"Generally, in arthropods, urbanization selects for smaller body size because there's less metabolic stress."
They also found that moths with a varied diet were better suited to city life than those with refined palates. Some caterpillars feed on a single species of plant and are among the first to disappear when an area is developed. Moths whose larva can get by with several different plant species are more resilient in the face of urbanization.

Most worringly of all, the team took samples only from protected areas yet still observed marked declines.

"It's shocking to see how strong these declines are in a city that's not deeply urbanized," Guralnick said. "We're talking town-sized, as opposed to something like New York City."

Michael W. Belitz et al, Substantial urbanization‐driven declines of larval and adult moths in a subtropical environment, Global Change Biology (2024)
https://onlinelibrary.wiley.com/doi/10.1111/gcb.17241

[kassy]

Oxidant pollutant ozone removes mating barriers between fly species

Elevated ozone levels increase the occurrence of mostly sterile hybrids between different species of the genus Drosophila

nsect pheromones are odor molecules used for chemical communication within a species. Sex pheromones play a crucial role in the mating of many insects. Species-specific odors attract males and females of the same species. At the same time, they maintain the natural boundaries between species.

The research team led by Nanji Jiang, Bill Hansson and Markus Knaden from the Department of Evolutionary Neuroethology at the Max Planck Institute for Chemical Ecology has previously shown that elevated ozone levels severely disrupt chemical communication within fly species: Ozone breaks the carbon-carbon double bonds found in most insect pheromones. As a result, male flies can no longer distinguish between females and other males and therefore court both sexes (Air pollution impairs successful mating of flies, March 14, 2024).

In their new study, the researchers investigated whether the degradation of sex pheromones by ozone also affects the mating boundaries between different species. "In particular, we wanted to know whether elevated ozone levels remove mating boundaries between species and what the consequences of a possible hybridization are. We know from previous experiments that ozone can severely disrupt mate choice in insects. Our current study indicates that even slightly elevated ozone levels, which nowadays are not uncommon on summer days in many places, cause flies to hybridize more frequently with closely related species, which could lead to a decline in insect populations due to the infertility of the resulting hybrids," says first author Nanji Jiang, summarizing the key message of the study.

Inter-species mating occurs under elevated ozone levels

The scientists chose four species of the genus Drosophila for their experiments. While Drosophila melanogaster and Drosophila simulans are cosmopolitan species found all over the world, their relatives Drosophila sechellia and Drosophila mauritiana are island-endemic and, as their names suggest, are only found in the Seychelles and Mauritius respectively. All four species use very similar pheromones, but mix them in a species-specific way. It was therefore crucial for the research team to be able to measure the quantitative changes within the pheromone mixtures after exposure to ozone.

In the mating experiments, the flies were exposed for two hours to ozone concentrations that are often measured on particularly hot days in our cities. The scientists gave ready-to-mate females the opportunity to choose between a male of the same species and a male of a different species. After a few hours, they separated the females from the males and allowed them to lay eggs. To determine whether the female had mated with a male of her own species or another species, the researchers analyzed the sexual organs of the male offspring, as species and hybrids can be distinguished on the basis of their morphology. The results of these tests showed that hybridization occurred more frequently under the influence of ozone, while few hybrids were found when the flies were previously exposed only to ambient air.

Fruit flies rely not only on chemical signals to mate, but also on the singing of species-specific songs, which they produce by vibrating their wings. Many species also use visual signals to attract mating partners. Despite these additional "aids," elevated ozone levels appeared to prevent some of the female flies in the study from distinguishing between conspecifics and males of other species. "Although we expected that the disruption of pheromone communication by ozone would lead to a slight increase in hybrids, we were surprised to find that some females were completely unable to discriminate between conspecifics and males of other species, despite other possible acoustic or visual cues," says Bill Hansson, Head of the Department of Evolutionary Neuroethology.

Hybrids: a dead end in evolutionary terms

Male hybrids in flies are usually sterile or at least less fertile than non-hybrids. Male hybrid offspring is therefore a wasted investment for the flies and can contribute to the extinction of populations. Unlike male hybrids, female hybrids are usually fertile and in some cases were even preferred by males in this study. Female hybrids could therefore be a source of continuous gene flow, which in the long term could lead to the emergence of hybrid species.

"The genus Drosophila comprises more than 1500 species, and it is known that more than 100 closely related species pairs can potentially hybridize. It is therefore not unlikely that pollutant-induced hybridization in some of these species pairs could lead to hybrid speciation," says Markus Knaden, assessing the chances of success of such a hybrid species.

Air pollution is an underestimated threat to insects

Insects rely on odors, not only when choosing a mate. In addition to sex pheromones, they use aggregation pheromones to attract conspecifics of both sexes or alarm pheromones to communicate in case of danger. Social insects, such as ants, navigate along pheromone trails or use colony specific odors to recognize their nest mates. Many of these odor molecules also contain carbon-carbon double bonds, which can be broken by ozone. The scientists fear that ozone could disrupt the chemical communication of insects in many areas, and now plan to investigate this in further studies, for example in ants.

Outside the laboratory, other oxidizing pollutants such as nitrogen oxides, which cannot be tested in laboratory experiments because of their toxicity, can amplify the effect of ozone. Limit values already exist for these pollutants because of their harmful effects on humans. "The limits for air pollutants should be re-evaluated, considering that even small amounts of these substances have a significant impact on the chemical communication of insects," says Markus Knaden. "As we are currently facing a dramatic decline in insect populations regarding their total biomass and their biodiversity, we should try to better understand and counteract all possible factors that potentially favor this decline."

https://www.sciencedaily.com/releases/2024/04/240411130213.htm