Are Grasshoppers Disappearing? : How Climate Change and Human Activity are Transforming the World of Grasslands - The True Nature of Grasshoppers That Defies Their "Pest" Image

When you hear the word "grasshopper," you might first think of an insect that ravages fields or one that surprises you by jumping suddenly. Particularly, the name "Warzenbeißer" might even sound somewhat ominous. However, what the German article conveys is a profound world of grasshoppers that cannot be captured by such simple images. While they play an important role in nature, many species are now endangered due to habitat degradation.

In Europe, over 1,000 species of grasshoppers and 49 species of mantises have been identified, with about 80 species of grasshoppers and one native mantis species in Germany. Even if they look similar, their lifestyles and habitats differ. There are various forms, such as those with robust bodies like the Warzenbeißer, mole crickets that live underground, and species that display vibrant wings. Grasshopper species are divided into those with long antennae and those with short antennae, and their ways of producing sound differ. Those with long antennae rub their wings, while those with short antennae rub their legs and wings to make sounds.

The name "Warzenbeißer" literally means "wart biter," originating from the belief that its bite and body fluids could cure warts. Of course, modern science does not recognize this. Instead, this name reflects how people once layered various folk beliefs onto insects. Although the name sounds terrifying, in reality, it is just one of the insects quietly living in the grasslands.

So, what role do grasshoppers play in nature? First, they eat plants, breaking down the hard leaves and stems into a state that other organisms can easily use. This advances the decomposition of organic matter, contributing to soil formation and fertility. Additionally, as grasshoppers themselves become food for birds and spiders, they occupy an important position in the food chain. Regardless of personal preferences for their appearance, the ecosystems of grasslands and fields are supported by these small insects.

Furthermore, grasshoppers can be clues to understanding environmental conditions. Each species prefers different grass heights, soil, moisture, and temperatures, and many spend most of their lives in the same environment. Therefore, observing which grasshoppers are present can reveal whether the land is a dry grassland, a wet meadow, or if the environment is deteriorating. Experts point out that grasshoppers can be indicators of the "quality of environments with living organisms."

However, these grasshoppers are now in crisis. According to the Red List published by the German Federal Agency for Nature Conservation, 26 species, about one-third of Germany's grasshoppers and mantises, are in dangerous conditions due to population declines and other factors. The background includes habitat loss and fragmentation due to grassland modification, wetland drainage, development, and intensive agriculture. Particularly, areas that appear to have "low productivity," like poor grasslands and semi-dry grasslands, are actually irreplaceable habitats for many insects.

On the other hand, climate change does not affect all grasshoppers equally. Some species that prefer warm climates are expanding their distribution. The European mantis is a representative example, with its habitat reportedly expanding in Germany over the past 20 years. In other words, while climate change is a tailwind for some species, it increases the difficulty of survival for others. A "winner" and "loser" dynamic is emerging even in the insect world, and the state of biodiversity is undergoing significant changes.

On social media, there are various reactions to these topics. On X (formerly Twitter), there are voices expressing surprise at the impact of the name Warzenbeißer, and comments like "I'm not fond of their appearance, but if they play an important role, my perspective changes." Additionally, there are posts recalling changes in local nature, such as "I used to see them commonly in the grass when I was a child, but it feels like they've decreased a lot recently" and "I have a real sense that insects have decreased." Posts introducing Warzenbeißer and insect diversity by local nature conservation organizations and media also receive reactions like "I want to preserve environments where such creatures can live" and "The name sounds scary, but they're actually cute," reflecting a simple fondness and sense of crisis regarding insects.

However, grasshoppers are not unrelated to humans. Depending on the species, they may eat crops or affect gardens and fields. Mole crickets can dig underground and damage roots. However, at least in Germany, it is said that large non-native grasshopper species have not erupted and established themselves as serious pests. While some brought in as pets or reptile food may be found temporarily, the climate and other conditions do not suit them, preventing them from widely establishing in the wild.

What this story reveals is a reflection on our tendency to judge living things solely based on whether they are "useful" or "harmful." Grasshoppers indeed sometimes eat crops, and many people are not fond of their appearance. However, in nature, they help decomposers, support other animals, and alert us to environmental changes, making them important beings. If grasshoppers decrease, it does not merely mean the reduction of one insect species; it could indicate that the grassland or wetland environment of that area is being compromised.

In Japan, too, many people might feel that "there used to be more insects." As riversides, vacant lots, satoyama, and areas around rice fields are developed and homogenized, insects that were once common are disappearing. Using the grasshopper with the slightly peculiar name Warzenbeißer as a starting point, perhaps we should pay more attention to changes in the nearby grasslands. Grasshoppers are small creatures on the fringes of nature, but their existence quietly questions what kind of environment we are trying to preserve.

【Source】
- Introduction to Warzenbeißer and German grasshoppers, based on articles and expert explanations
https://www.op-online.de/welt/warzenbeisser-co-was-man-ueber-heuschrecken-wissen-sollte-zr-94263958.html

- Red List announcement by the German Federal Agency for Nature Conservation (BfN) (basis for one-third of Germany's grasshoppers and mantises being at risk)
https://www.bfn.de/pressemitteilungen/rote-liste-rund-ein-drittel-der-heuschrecken-bestandsgefaehrdet

- Explanation by the Baden-Württemberg State Environmental Agency (LUBW) (grasshopper calls, roles in ecosystems, significance as environmental indicators)
https://www.lubw.baden-wuerttemberg.de/natur-und-landschaft/heuschrecken

- Introduction to Warzenbeißer by NABU (German Nature Conservation Association) (origin of the name and conservation significance)
https://www.nabu.de/tiere-und-pflanzen/insekten-und-spinnen/heuschrecken/36791.html

- Overview by German-speaking professional organizations and media (reference to over 1,000 species of grasshoppers in Europe and about 80 species in Germany)
https://dgfo-articulata.de/heuschrecken
https://www.wochenblatt-reporter.de/karlsruhe/c-ratgeber/insekten-tagung-in-karlsruhe-warum-heuschrecken-verschwinden_a750894

- Reference to reactions on social media (examples of posts about Warzenbeißer and insect diversity on X)
https://x.com/derspiegel/status/1996272354004173151
https://x.com/lfu_bayern/status/1925505962858725849