This series of books looks in detail at those animals that are now extinct and those that are endangered. What is extinction? And when does an animal become classified as endangered? Starting with the known mass extinctions from prehistory, including the dinosaurs, the series looks at the main biomes of the world, looking at extinction and endangered animals in each. It also looks optimistically at what can be done to save some precious species. Endangered and Extinct Animals of the Wetlands, Rivers and Lakes takes a look at why our river dolphins and wetland mammals are under threat, why so many fantastic fish have been lost to the world, why spectacular water birds are having trouble swimming and how pollution and human activity affects wetland wildlife.