1. Eurasian or common curlew - once considered common, recent research indicates that there are fewer than originally thought.
2. Plover - a variety of different species of Plovers inhabit the Danube river region and some are considered critically endangered.
3. European Tree Frog - tree frogs were once used as barometers because they croak before it rains.
4. Common kingfisher - these colourful birds boast blue areas on their wings, tails and heads, and can be found throughout Europe, northern Africa, and large parts of Asia.
5. Wels catfish - these bottom feeders normally grow to about 1.5. meters and weigh 15-20 kg, but the largest can grow more than 2 meters long and weigh over 100 kg.
6. European ground squirrel or European souslik - these squirrels use lookouts to watch for danger, and warn other squirrels with a shrill alarm.
7. Sturgeon - Several species of sturgeon inhabit the Danube river basin, and all are considered threatened or endangered species. Some species of sturgeon native to the Danube are thought to be extinct. To learn more about the sturgeon, visit our website at ICPDR.org.