1. Ecosystems are being transformed and destroyed (e.g. through more intensive land use and increasing development)
2. Humans directly exploit ecosystems (e.g. through deforestation or overfishing)
3. Pollutants pollute the environment (e.g. through the discharge of toxic substances or over-fertilization)
4. Climate change (e.g. due to rising temperatures, drought or extreme weather events)
5. Invasive species displace native animal and plant species

Although climate change is not the main cause of biodiversity loss, its significance is rapidly increasing. Particularly in ecosystems that have already been damaged, it leads to fewer individuals surviving, species becoming locally extinct and habitats being destroyed.

Climate change affects biodiversity in different ways. Here are a few examples:

• Habitats and dispersal areas are changing due to climatic changes. In Wiesbaden, for example, we now encounter parakeets and the Asian tiger mosquito, which thrive in the warm climate. The grass frog, on the other hand, can hardly find the shallow ponds it needs for its offspring.
• Animals and plants are changing their behavior. Many of our native birds, for example, breed much earlier in the now often warmer springs. The cuckoo therefore finds fewer and fewer nests in which to lay its eggs after returning from its winter quarters.
• Climate change is leading to declining numbers of individuals in many species. As a result, the fire salamander, for example, is finding fewer and fewer reproductive partners.

There are also animal and plant species that benefit from changing climatic conditions, for example by expanding their range. However, the number of potential climate losers is significantly higher.