An insect apocalypse? It is just a bit more nuanced

Insects have a hard time in many places. But not everywhere.

In recent years, we have heard a lot of worrying news about the loss of insect populations. In 2019, for example, a study stated that an estimated 40% of all insect species are currently threatened with extinction. In the meantime, much more research is being done into the condition of insects and how they are doing worldwide. And fortunately that also leads to a more nuanced picture of the current situation.

Decrease
At first glance, insects may seem indestructible. More than a million species have now been described and, moreover, insects crawled across the earth 400 million years ago. But appearances can be deceiving. Recent studies have noted a significant decline in insect numbers. For example, many insect populations around the world are declining by about 1-2 percent every year. If you continue this over a few decades, the situation can become quite dire. Scientists have therefore expressed concern about the future of the insect in a world undergoing change as a result of human activities.

By man
Indeed, because according to several studies, the decline of insect populations must be placed against the background of the growth of the human population. Today, we are 7.8 billion people who exploit most of the land for agriculture. “Insects are like the canaries once used to warn miners of the presence of poisonous gases,” said researcher Philip Batterham, of the University of Melbourne. “The demise of insects alerts us to the way we are misusing our planet by destroying habitats, climate change and the overuse of pesticides.”

German nature reserves
This loss of insects is also noticeable among our closest neighbors. Different studies have already shown that today in German meadows there are far fewer animals chirping, buzzing, crawling and fluttering compared to 25 years ago. In addition to a strong decrease in the total biomass of flying insects, the diversity of species has also decreased in German nature reserves. This applies in any case to gliding, as researchers from Radboud University show a new study On. The number of copies has declined across the board.

Gliding species
The researchers have thus observed a worrying decline in the number and diversity of hoverfly species. In 2014, for example, a total of a quarter fewer hoverflies were caught compared to 1989. “This is added together over the entire season,” explains researcher Eelke Jongejans. “However, if you look on a daily basis – in other words the number of types of hoverflies that actually fly around in a day – then the decrease in 2014 was about 82%. This provides an important picture of the decreased activity of hoverflies, which play an important role in the ecosystem as pollinators and aphid control agents. ”

Common types
What is striking is that not only rare species seem to have a hard time. Relatively speaking, the researchers saw the strongest decrease among common species, and not just the disappearance of rare hoverfly species. So we see a decline across the board. The suspicion that a decrease in biomass also leads to less biodiversity therefore appears to be correct.

So it looks like insects have been pretty cornered and an insect apocalypse may be lurking. Fortunately, that is just a bit more nuanced. It is true that insects have a hard time in many places. But not everywhere. In the UK, for example, the number of butterflies has declined by a hefty 50 percent since 1976, while at the same time several other insect species are being discovered that are actually increasing in numbers. This mainly occurs in temperate and arctic regions, where insects have traditionally been rare due to the harsh, wintery conditions.

Differences
So it turns out insects by no means to be cornered everywhere. The differences can be very large from place to place. The number of insects in one place can therefore just decrease, while in another place there is a stable situation or even an increase. It shows that the condition of insects is quite complex. “The key message is that we must invest in assessing and monitoring our precious insect communities because we simply don’t know if native insects are in decline,” said scientist Greg Holwell, of the University of Auckland. “What’s good is that there are now more people who notice the insects. And this could lead to greater appreciation and more conservation efforts. ”

“Insects have been described as the little creatures that rule the world”

Important
And that is important. Insects are essential for many ecological processes that people rely on, such as our own food supply and the recycling of nutrients in the soil. In addition, insects are the staple food of many birds, bats and reptiles. Insects are therefore of great importance to our ecosystems. “Insects have already been described as the little creatures that rule the world,” says researcher Saul Cunningham of the Australian National University. The decline in insects therefore affects us all, something we may not realize enough. “There are two world clocks ticking,” Batterham says. “With every passing minute, the world’s human population is increasing, while the available land that can be used for agriculture is decreasing. We need to intensively research how human activity affects insects and find sustainable ways to produce our food. ”

Bright spot
Fortunately, there are also bright spots for insect recovery. This year, for example, a large national collaboration project was started in our own country. In various places in the Netherlands, including the river area in the Ooijpolder-Groesbeek region, the possibilities for restoring biodiversity are being investigated. And that offers perspective. “I am sure we will not be late,” says project leader and professor of Experimental Plant Ecology Hans de Kroon. “We can make the insects in these areas bounce back.”

However, a good plan of action is needed. Because if we do nothing, the constant loss of insects will affect our daily life in ways we cannot yet imagine. However, insects can take a beating. So if we make their lives a bit easier, they might get better.

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