I saw a couple of interesting articles on the internet this morning that are almost related to each other.
As part of a scheme to repopulate Scotland with some of its native fauna (following on from the reintroduction of beavers) a number of White Tailed Sea Eagle chicks have been released in the last few years in the east of Scotland. These are chicks that have been brought over from Norway and kept in aviaries in the Fife area prior to being released. The next batch of chicks is going to be tagged in order to check their progress and look at their movements. More information about this bird can be found in the article on the RSPB website.
At the other end of the scale British Waterways has released a list of the twelve non-native species most likely to harm our native river dwelling wildlife. Not surprisingly the list includes the much publicised mink and Signal Crayfish, but also Red-Eared Terrapin (apparently released following the ninja turtles craze), a number of plants such as Japanese Knotweed and Zebra Mussels, the latter already causing problems in the rivers and lakes of, amongst others, Spain and Canada. The problem common with most of these invaders is that they tend to grow bigger, faster and are more aggressive than our peaceful native species.