I read this really interesting article in National Geographic about the sharp decline in insect populations across the globe titled “Where have all the insects gone?” It’s the cover story for the May 2020 issue.
It’s a subscribers only article, so if you are a subscriber, I highly encourage you to read it. If you aren’t a subscriber, below are some of the key takeaways.
First, insect populations are indeed dropping at alarming rates. Entomologists (scientists who study insects) in Germany have noted a 76 percent drop in insect biomass between 1989 and 2016. This comes from data gathered in 63 protected areas in Germany. The entomologists kept the control the same. I.e. They used the same trap that they used in the late 80s and 90s.
Second, scientists are still figuring out what exactly is causing the drop in insect populations. It’s likely a combination of more people inhabiting the planet, pesticides, and global warming. But what among those three is the most impactful? That’s what they’re trying to figure out.
Third, there are a LOT of insects out there. It is estimated that any given moment, there are 10 quintillion insects living on this planet and five million species, one million of which have been identified. That’s right, scientists think they’ve only identified 20% of the insect species in the world!
Fourth, we really need insects. While there have been some debates about whether or not we need Mosquitoes, there is no debate about whether or not we need insects. Here are some key reasons for why we need insects:
Insects are key cogs in the food chain, providing food for many animals such as birds, bats, amphibians, and fish. The drop in insect populations has been linked to the drop in bird populations.
Insects also decompose: “Dung beetles process parasite-breeding and grass-killing cattle dung in 23 months versus the 28 it would otherwise take.” Without insects, things wouldn’t decompose nearly as quickly, impacting the health of our soil.
Insects also act as pest controllers. While there are some insects that harm our crops, there are insects built in that feed on them and keep their population levels in check. Maybe we shouldn’t be so reliant on pesticides?
Insects are crucial in the pollination process of plants: “Nearly 90 percent of flowering plant species and 75 percent of crop plant species depend on pollination by animals—mostly insects. Overall, one out of every three bites of food humans eat relies on animal pollination in the production process.” No pollination from insects, no food for humans and many just about every animal on land.
Insects act as soli engineers: “Termites and ants can transform soil in hot, dry climates. Their tunneling aerates hard ground, helping it retain water and adding nutrients. In some regions, the introduction of termites has turned infertile land into cropland within a year.” No insects and we see “soil in arid regions become barren, crops fail, and increase in deserts.”
Just how valuable are insects? In 2006, a pair of entomologists tried to estimate the value of insects into four categories of services: “dung burial, pest control, pollination, and wildlife nutrition.” While it’s hard to estimate the value of insects into any monetary amount, the figure they came up with was $57 billion a year for the United States alone!
Once again, if you have a subscription to National Geographic, do read the article. It’s excellent. It’s really important we do everything we can to help out our little crawling friends. Without them, we too may soon follow them.