Nature reserves are among the most strictly protected areas in Germany. They are primarily designated to preserve the habitats of protected animal and plant species. In Bonn, there are eleven nature reserves in which rare and strictly protected animal and plant species find unique retreats.

In order to preserve the recreational areas and protect the sensitive and valuable habitats and species, important rules of conduct apply in nature reserves, which must be observed at all times:

• Dogs must be kept on a lead at all times in nature reserves.
• Recreational use is restricted to the official paths and roads and it is strictly forbidden to leave the paths.

Allowing dogs to run free within nature reserves poses a danger to the animals and plants living there because

• disturbing the breeding activities of ground-nesting species such as robins during the breeding season . If the parent birds are chased away by free-roaming dogs, they may abandon the nests with their young, causing them to starve.
• migratory birds are dependent on resting areas in Bonn's nature reserves on their long flights. If, for example, wild geese are disturbed by loose dogs or people, they flee and have to look for new resting places. This leads to considerable additional stress, as the animals are naturally exhausted by their long migrations.
• free-roaming dogs are perceived as a danger by wild animals such as wildcats. The animals flee and can sustain injuries in the process. If the animals are even chased by a hunting dog, they can die as a result of exhaustion.
• the droppings of the dogs lead to a constant influx of nutrients, which can push back sensitive nutrient-poor habitats and plants. The "Rodderberg" and "Düne Tannenbusch" nature reserves, for example, are important for their nutrient-poor soils and specialized plant species, such as the carthusian pink. Nutrient-poor soils are endangered and rarely found in Bonn.