Nightranger
Senior Moment
Alan Hobson said:a) there is no conclusive eidence that it is British Ruddy Ducks cross-breeding with the Spanish population, and b) Ruddy Ducks are an attractive and welcome addition to the British countryside - they enhance it. As do Little Owls, Red-legged Partridges and many other "alien" species.
a. Alan, there is evidence that ruddy duck are hybridising with WHD and that they are UK birds. There has been a genetic study on continental ruddy ducks that proves they come from UK stocks not that this matters as it is a diversion from the real matter in hand - that of an introduced alien causing problems. Think mink! Think grey squirrels!
b. I am sorry guys but aesthetics just does not cut it as a valid argument. How would you feel if little owls had displaced barn owls? OK I accept that some introductions are benign but think about why this should be. Little owls were once a British bird anyway as we know from fossil evidence and all that has happened is that they have reclaimed the niche with the help of humans. Even then, it took a few attempts before they got established. Red-legged partridges come from the near continent were the ecosystem is not significantly different from the UK. Ruddy ducks come from western USA, they are not genuine vagrants (unlike Canada geese albeit not the race that was introduced).