Welcome to Brainstuff from How Stuff Works. Hey there, brain Stuff, Lauren Vogel. Bomb here. When you hear the word armageddon, you might imagine a battle thought at the end of the world by humans. But it's possible that battle is being fought right now. Only all the casualties are bugs. Insects are vitally important to the functioning of the world's ecosystems. They do most of the plant pollination, after all, while providing food for the bulk of the world's birds, amphibians, reptiles,
and mammals. They're also essential in nutrient cycling, breaking down the world's dead stuff, manure, and what have you to make more dirt for us to grow our food in. Every ecosystem on the planet needs insects, which is why the apparent tanking of bug biomass is so alarming. Study published in October in the journal Plos one confirms the insect decline that many scientists and insect enthusiasts previously suspected, and it turns out their suspicions weren't just validated, but surpassed.
In Germany, insect biomass is declined by roughly seventy percent over a little less than three decades. We spoke with co author Casper Hallman of the Institute for Water and Wetland Research at Radbound University in the Netherlands. In an email, he said declines in insects as a group have been suspected for quite some time, indirectly through declines in insectivorious birds, but around the globe only a few data sets exist to inform us, and these data are mainly concentrated around bees,
butterflies and moths. Since a group of amateur entomologists in Kerfeld, Germany, has been collecting all kinds of insects from sixty three German nature reserves between spring and autumn each year, following a highly standardized sampling protocol. Over the years, they realized that the tent like traps specially designed to catch flying insects were yielding a smaller and smaller catch each year, even though every aspect of their sampling regime remained constant.
Weighing the total biomass of the yearly hall over time allowed them to quantify it exactly how big a hit
these flying insects have taken over the decades. They found an overall three quarters decline in insects when they looked at the entire collecting season, but in high summer, when insect numbers are at their highest, the decline was even more noticeable at These findings are of course specific to Germany and data are very scarce for nature preserves in other parts of the world, but the drop in insect
populations is in no way limited to Germany. The study authors speculate that their study locations are representative of similar preserves around the world, and study published in the journal Science detailed the decline in worldwide populations. The reason it's important to compare these data to those taken from other protected areas has to do with the fact that agricultural or urban areas have relatively little to offer insects and
are often outright toxic to them. Therefore, it's tough to note based on data from these areas whether insects are doing poorly in other places in the world, in habitats where they should be thriving. That said, general data sets on butterflies, moths, and most famously bees around the world
mostly point in the same disabal direction. Additionally, the so called windshield phenomenon might not be data driven science, but it seems that all over the world in recent decades, people have been noticing fewer squashed bugs on their windshields than ever before. But what could be causing this more than decimation of Germany's insects. While the research team looked at whether changes in climatic conditions, the landscape, or the local habitat may have caused the decline, co author Hallman
says they were unable to explain it based on these analyzes. Quote, Our best guess at this point are the negative influences of land use surrounding the nature reserves, particularly agricultural practices such as extensive use of pesticides and fertilizers, as well as over decline in habitat sustainability in between the reserves. But the effects of so many fewer insects can already
be observed in the decline of birds in Germany. During the same time period, twelve million pairs of breeding birds have disappeared, and the same trend has been observed in other parts of Europe. So the next time you see a bug in your house, reconsider squashing it and maybe just escorted outside. It's kind of having a tough thirty years of it. Today's episode was written by Justlyin Shields
and produced by Tristan McNeil. For more on this and lots of other depressing yet important topics, visit our home planet, how Stuff Works dot com