Insect extinction: Who will pollinate our plants?

by (comments: 0

Do you remember when you used to go on family vacations with mom, dad and your siblings? Dad had to take on the nasty task of cleaning the windshield at every fuel stop, as there were hundreds - if not thousands - of smashed insect carcasses stuck to the outside of the window. Once the window was nice and clean again and the journey could continue, it was never long before the next bug burst with a dull "plop" on the windshield. Children of the 90s are perhaps the last generation to experience this phenomenon at first hand...

Nowadays, we don't have to clean the windows and can drive from Stuttgart to Berlin with a clear view without having to clean the windshield even once. What at first sounds like a relaxing car journey - after all, who likes cleaning insect carcasses from windows? - is, however, a deeply worrying development: Within a few decades, the number of insects has fallen drastically.

Insect mortality: many causes and drastic consequences

Name Insect mortality
Problem 75 percent decline in insects in Germany
Causes Intensive agriculture, land sealing, climate change
Consequences "Pollination crisis", holes in the food chain, shrinking biodiversity
Solution Expand food supply, create habitat

Insect mortality (or insect decline) has many causes - and drastic consequences. Insects are the foundation of our natural world and without bees, butterflies and the like, we would be pretty much screwed: Who would pollinate all our plants that provide us with food? What will birds, fish and other animals feed on if there are no more insects? And who decomposes the dog poo at the side of the road if there are no more flies? Insects perform the most mundane tasks that keep our ecosystem in balance and make our life on earth worth living. And yet they are massively threatened with extinction.

In the 2017 Agricultural Report, the Federal Agency for Nature Conservation described the problem as follows:

  • The insect biomass is in significant decline
  • Nature reserves are also affected (80 percent decline)
  • Birds, bats and small mammals are threatened
  • 41 percent of wild bee species are endangered

The Federal Agency for Nature Conservation also investigated the reasons for the decline of insects in Germany and identified the following causes:

  • Structural impoverishment in agriculture
  • Large-scale use of plant protection products
  • Use of seed dressing (neonicotinoids)
  • Narrowing of the crop rotation
  • Elimination of edge structures and flower strips
  • Nutrient oversupply in the soil

Insect mortality in Germany: 40 percent fewer insect species

Insects are the most species-rich class of animals on our planet. Think of all the little beetles, bees, butterflies, bumblebees and moths. Whether on land, in water or in the air: insects are simply everywhere. They decompose leaves, provide food for other animals and pollinate flowers. And yet we humans are allowing a massive decline in insects to occur. The Federal Agency for Nature Conservation says that there will be 40 percent fewer insect species in Germany in the long term. But it is not only the number of different species that is affected by insect extinction.

The total number of insects has also fallen drastically: a famous study by the Entomological Association in Krefeld investigated how the insect population in this country has changed over a period of 30 years. Volunteers set up so-called Malaise traps in several nature reserves in North Rhine-Westphalia. These traps look like small tents and insects that get lost in them fall into a container of high-proof alcohol where they are preserved. After a year, the researchers come back and can then see how many different insect species live in the area; but they can also determine the total biomass of insects.

In 1989, a total of 1.4 kilograms of insects got lost in the traps of the Krefeld researchers - 23 years later it was only 300 grams! The "Krefeld study" confirmed what many had long suspected: insect mortality has long been a reality. Even experts were shocked by the results, as very few researchers had anticipated an almost 75 percent decline in insects.

Insects: The most species-rich animal class in the world

Moths, bees, beetles, flies, bugs and dragonflies are all insects, and in Germany alone there are over 30,000 native insect species! Worldwide, almost one million insect species have been scientifically recorded to date. This means that over 60 percent of all animal species in the world are insects! Quite impressive. However, as insects are so small and diverse, researchers believe that there are many, many more insects living on our planet. Worldwide, 40 percent of pollinating insects are threatened with extinction or have already been wiped out. Here in Germany, too, some species have already become very rare, such as the green damselfly (a dragonfly species), the large oak hawk-moth (a beetle species) or the meadow blue (a butterfly species).

Of the almost 30,000 insect species in Germany, around 560 are wild bees. Depending on the federal state, between 30 and 70 percent of them are on the Red List and are therefore threatened with extinction. And this is despite the fact that they are specially protected by law: According to ยง 39 of the Federal Nature Conservation Act, all wild bee species are protected! You can find a catalog of fines and further information at www.bussgeldkatalog.org

Causes of insect mortality: Modern agriculture destroys habitat

Insect mortality has many causes and more than just one scapegoat. Even if there are conspiracy theorists who claim that wind turbines or cell phone radiation are to blame for insect deaths, serious scientific studies point to other causes. Intensive agriculture is right at the forefront. Monocultures, over-fertilization and the use of pesticides have a twofold effect on insect mortality: Firstly, important food sources and habitats are destroyed; secondly, toxic chemicals kill the insects.

When fertilizing farmland, many farmers use nitrogenous fertilizers and dump them liberally on their fields. After the fertilizer seeps into the soil, it reaches the groundwater and spreads to the entire surrounding area. Many wildflowers - the food sources of bees and insects - cannot tolerate this excess nitrogen from the fertilizer: they wither and can no longer grow in the surrounding area. The use of monocultures causes additional problems: instead of many different plants, farmers only cultivate one species. However, many insects are specialists and cannot live on the nectar of these plants and are dying out in these regions.

Insecticides, herbicides, pesticides: poison for bees?

However, bees and insects are not only being displaced passively and due to a lack of food. Researchers agree that the use of pesticides is a major driver of insect mortality. But what exactly are pesticides? Pesticides is the generic term for all plant protection products. There are agents against pests, such as mites and aphids (insecticides); agents against "weeds" (herbicides); and agents against mold (fungicides). However, the use of pesticides not only combats and kills pests, but also causes considerable collateral damage: Bees, bumblebees, butterflies and thousands of other insects die or are harmed.

One type of insecticide is particularly dangerous for bees: neonicotinoids. This artificially produced insecticide binds to the receptors of nerve cells, where it interferes with the transmission of nerve impulses. This is not so dramatic for us humans and vertebrates. But for insects, neonicotinoids have fatal consequences. The German Nature and Biodiversity Conservation Union is also repeatedly concerned with the problem insecticide and says: "Various studies suggest that neonicotinoids not only have an impact on so-called plant pests, but also on butterflies and especially bees." Furthermore, a British team of researchers found that bees do not avoid plants that have been treated with neonicotinoids, but actually target them. Contact with the plants causes fewer bees to reproduce and leads to a decline in insects.

Sealing of surfaces: Concrete and stone deserts instead of colorful flowers

Agriculture is not the only factor contributing to insect mortality. Increasing urbanization and the associated sealing of areas is also harming wild bees and insects. Roads, houses and rock gardens are being built where wild flower meadows once stood and offered wild bees a refuge.

Many (front) gardens in towns and villages are home to many flowers and are well-intentioned; however, plants are often planted that are not native to Europe (neophytes) and these are unfortunately not to the liking of our native wild bees. Often only "beautiful" flowers, such as geraniums or cultivated roses, are planted, which produce very little nectar and pollen. Wild bees and insects are much happier with species-rich flower meadows where they have the full range of native flowers.

Prevent insect extinction: Create meadows for wild bees

Surprisingly, there is currently a higher density of wild bees in many urban areas than in the surrounding rural areas. For example, 261 wild bee species have been recorded in the urban area of Berlin and 258 in Stuttgart, which means that between 50 and 90 percent of wild bee species live in cities, depending on the region! There are many reasons for this, but the most important is that there is a greater supply of food in cities than in the countryside. Instead of endless rapeseed and maize plantations, as in the countryside, there are now more wildflowers in gardens, parks and green spaces in cities. There is a veritable urban exodus of wild bees fleeing the threat of pesticides and lack of food in the countryside. Although many people still associate living in the countryside with nature, biodiversity and species diversity is greater in many cities.

Basically, insect extinction can only be prevented if there are major changes in agriculture. No pesticides, less fertilization and a restructuring of the landscape with flower strips, hedges and more habitats for wild animals and plants. But you can also do something for wild bees today! Plant native, bee-friendly plants in your garden, in a flower box or in open spaces in your city.

How to prevent insect mortality

Please note the following: Please avoid all pesticides and other chemicals! This is because wild bees and other insects are severely damaged by many products and can even die. You should also consider a few things when selecting plants. You should not only choose plants for visual reasons, but rather whether they provide plenty of food for wild bees. After all, a bee meadow should be for the bees and not for you! Another important point to consider is the flowering time of the different flowers. With a flowering calendar, you can ensure a continuous flowering phase. Finally, it is important that the wild bees have a place to nest. Homemade wild bee hotels, but also stones, walls or dead wood are welcome "sleeping places" for wild bees.

With Bee friendly bee seed, you can create valuable food sources for wild bees. As soon as the herbs, summer flowers and wildflowers start to bloom, the wild bees feel like they are at an all-you-can-eat buffet in the land of milk and honey. Whether on the balcony box in the office or on the flower bed in the garden: every flower has the potential to nourish a wild bee and stop insect extinction.

(mw)

Go back