Invasive species spread across Europe

Nutrias (Myocastor coypus), native to South America, were brought to Europe for their fur. Today, they are seen as an invasive species. They feed on aquatic plants, weaken embankments and dikes by digging burrows and displace native species. Excellent swimmers, they weigh up to 9 kilograms (20 pounds). Generally harmless to humans, they can still cause significant ecological and economic damage.

The Egyptian goose (Alopochen aegyptiaca) is native to Africa, but has spread widely across Germany and many other European countries. Recognizable by its striking plumage and relatively large size, it competes with native waterfowl for nesting sites and food. Its aggressive behavior can also displace other bird species.

Sika deer (Cervus nippon) are native to East Asia and are now found in many zoos and wildlife parks. In parts of Germany, they are also considered an invasive species. They compete with native red deer for habitat and food and can interbreed with them. This threatens the genetic integrity of native red deer populations.

The spiny-cheek crayfish (Faxonius limosus) is native to North America. It has spread rapidly and carries crayfish plague, which spreads to native European crayfish. As a result, native crayfish populations have declined sharply in many places. Although harmless to humans, the spiny-cheek crayfish poses a significant threat to freshwater ecosystems.

The raccoon (Procyon lotor), brought to Germany for fur farming and native to North America, has spread across much of the country. An opportunistic feeder, it raids nests for eggs and young birds and also eats amphibians and small mammals, putting pressure on local wildlife. While generally not dangerous to humans, they can carry diseases and parasites — and are adept at raiding trash cans.

The Nosferatu spider (Zoropsis spinimana), which is widespread in the Mediterranean region, has also been sighted in Germany in the last few years. Since no significant damage to native ecosystems has been documented to date, it is not currently considered an invasive species under the EU regulation. It is largely harmless to humans — but its bite can be painful.

The Asian hornet (Vespa velutina) is native to East Asia and has been spreading across Germany and Europe in recent years. As an invasive species, it primarily preys on honeybees and wild bees, putting pressure on native pollinators. For healthy people, it is no more dangerous than other hornets, but it can pose a serious risk to those with allergies.

The Asian tiger mosquito (Aedes albopictus) is native to Southeast Asia, but is spreading further and further in Europe. It can transmit pathogens such as the dengue, chikungunya and Zika viruses. The risk of infection in Germany is still low, but it's increasing as the species continues to spread and temperatures rise.

The rabbit-headed puffer fish (Lagocephalus sceleratus), native to the Indo-Pacific, is on the rise in the Mediterranean. Its flesh and some of its organs contain the highly toxic neurotoxin tetrodotoxin, which can be fatal if consumed. It also displaces native fish species and harms the fishing industry. In Greece, fishers are even paid a bounty for catching it.