"Species cleansing" can get very fraught, too, when the species concerned is
cute, attractive and popular. This is happening in the UK with the Ruddy Duck,
which is an American species. It breeds happily in small number on lakes and
gravel pits and appears to do nobody any harm. It was even taken up as the
emblem of a major bird group. But then it was proposed that Ruddy Ducks could
find their way to Spain and interbreed with the very rare and endangered
Although there is no proof that this has happened, and the real problem with
White-headed Ducks is degradation/removal of habitat, an expensive
Government-sponsored (and European supported) cull of Ruddy Ducks went ahead
against much opposition from a variety of quarters (including me!). It seems to
have stalled at the moment but I am not sure why.
Compare this with the Mandarin Duck - also naturalised on many lakes in
southern England. This appears to be welcomed by all (it is a stunning little
duck) and it is now reckoned that there are more in the UK than in China and
that the UK population is an important species reservoir.
I can only agree with the person who said that all this seems to some extent
subjective. We have recently allowed Ring-necked Parakeets to establish.
Probably too late to do anything about it now, but we could have done 10 years
ago. They compete with native birds for nesting holes - but they are attractive
By the way, I agree that Canada Geese should not be welcomed. They are
controlled here in nature reserves, by removing eggs, or replacing them with
dummies, or similar techniques, otherwise they just take over the ponds and
wetlands. In town parks they are a real nuisance.