They would almost certainly be European. Oddly enough Derek Gow is quite possibly the 'origin' of most of them, or at least the middle man in helping private land-owners import them. I suspect the vast majority are from Germany, as they attempt to control the population through relocation or euthanasia. Wrong race? Which is the right race? Scandinavian animals have been compared most closely to sub-fossils from Great Britain, but I suspect there are no true races just zonal variation due to latitude. Individuals have been moved around so much in the past due to having been extirpated from much of it's traditional range. Any (European) beavers in the UK are better then none. As a species they are probably more tolerant of being placed out of the 'normal' range, as opposed to the bustard example (although migration is probably more the critical point with the Spanish bustards).
Definitely European , I think tetrapod is right and that a lot came from Bavaria . Interesting how this has been kept quiet for , I imagine , quite a few years . Makes nonsense about last year's fanfare of the first wild birth . Derek Gow said there could now be hundreds in the Tay area and that removing them all would be impossible . He was strongly advocating a beaver release on the River Teifi in West Wales . I had a brief chat with a member of a group working on Welsh mammals . It seems there is still only one DNA-confirmed from scat proof of pine martens from Wales . They are now doing more work to attempt to establish how widespread the population of this elusive mammal is , there are reported sightings from a very wide area .
Zoo Brno, Czech republic, has pretty good beaver exhibit. (North American Beaver) Like you said, few mirrors and you can see into the lodge. Just a funny beaver story - my mother got stuck in a train few weeks ago, a tree fell over the rail... oh yeah, beavers! So they may cause some occasinal problems, but it´s definitively worth it, they are amazing creatures... Oh, and for all the Beaver-lovers here: If you are planning to visit Czech republic, there is a great new hiking trail, close the to town Tachov (1 hour by car from Pilsen Zoo). It´s called Water World (Vodní Svět) and one part of this trail is a view point from where you can watch wild European Beavers. Sightings cannot be quaranteed, of course, but it´s worth a shot.
