kimba@cogsci.ed.ac.uk (Michael Newton) (06/20/91)
rim@csadfa.cs.adfa.oz.au (Bob McKay) writes: > This won't work, at least with cockatoos. ... Released birds don't have the > learned background to survive ...... There are definitely counter-examples to this. I know of a number of released sulphur-crested cockatoos which have adapted to the wild. One at least has lasted ~10 years. There were no wild cockatoos in the area so the individual was easy to keep track off. I don't know if any of these released birds were captive-born but its likely at least some were. I'm not sure where this discussion started but his my tuppence worth. In general re-introducing captive-bred animals is very difficult but in most cases given sufficent resources and good people its possible. Its certainly not just a matter of setting the animals free. Cockatoos are a poor example because they suffur little predation. Poor predator-avoidance is a big problem with caoptive bred animals. I believe this caused recent re-introductions of Thick-Billed Parrots to fail. Cross-species fostering is one way to avoid this problem. The NZ conservation people used this to good effect to bring the Chatham Island Robin back from the brink. A New Scientist a year or two ago documented a number of other failures and claimed (I think) only 15% of re-introduction attempts have succeeded. The lessons learnt will hopefully produce better results in the future. My opinion is re-introduction is usually more difficult than captive breeding and usually more difficult than either is removing the factors which endangered the species. Andrew Taylor - using a borrowed account while in Edinburgh - don't mail it P.S I'm taking the long way to Africa. My 2 US stopovers, SF and NY, were both good - no life birds but its was good to see alcids, hummingbirds, New-World "vultures" again. Saw a couple of (locally) uncommon birds around Butler Sanctuary just outside NY - Red-Shouldered Hawk, Osprey, Red-Breasted Nuthatch, Kentucky and Hooded Warblers, Least Flycatcher (heard).