Great conservation plans ! :
Conservationists turn tiny New Zealand island into bold wildlife experiment | Environment | The Guardian
Conservationists turn tiny New Zealand island into bold wildlife experiment | Environment | The Guardian
yes there are. Stewart Island kiwi are not managed at all, because there are no mustelids on the island: the primary killer of kiwi chicks are stoats. On the main islands (the North and South Islands) any unmanaged populations will become extinct. Kiwi live a long time (over forty years) so populations will remain present for decades but if almost all the chicks are being eaten every year then when those adults start dying off the entire population will just crash. Operation Nest Egg started (back in 1995) with North Island Brown Kiwi because that was the species for which there was the most knowledge. Great Spotted, Okarito Brown and Haast Brown Kiwi came in more recently. A majority of the eggs from Okarito and Haast Kiwi are collected and hatched in captivity each year because there are only a few hundred birds of each.LaughingDove said:I didn't realise that kiwi populations were managed to this extent. Are there any completely unmanaged wild populations?
the island's ecosystem has already been destroyed. It was a forested island which was turned into farmland. The project is restoring it to a forested island. They are replanting the trees, and most of the wildlife will have to be returned to the island by humans; very little would find its own way back. It really isn't important if a lizard from the Auckland region is introduced there or a lizard from the Nelson region, or if it is used for creching kiwi or if they put some takahe there. It is never going to be a complete ecosystem anyway (not least because a lot of the species are now extinct). An important thing to know also is that very many of the "natural" ranges of NZ species are actually relict ranges; especially with the reptiles and invertebrates you will find a species now found only on one offshore island or at two mainland sites a thousand kilometres apart, but which was once spread over the entire mainland until rats arrived in the country. A good example from kiwi is the Okarito Brown Kiwi - now it is found only around Okarito which is a swamp town halfway down the West Coast of the South Island; formerly it was found right up the west side and top of the South Island and across the lower half of the North Island. One of the best-known island sanctuaries in NZ is Tiritiri Matangi, and that is no more natural than Rotoroa. It was farmland returned to forest, and most of the species now present were introduced there. The takahe there are not native (they are a South Island species - the North Island takahe is extinct), and the stitchbird population there depends almost entirely on humans to survive (there is only one truly self-sustaining stitchbird population left in the country [read: world]). It is the way it is in NZ now - if the native species aren't managed then many of them simply aren't going to exist any more.LaughingDove said:Whilst this particular project may be good in terms of protecting endangered species in a predator free environment, the thing that I was questioning was the idea of protecting species by moving them to places away from their threats where they are not native. As the article said, the idea of "creating an ecosystem anew" and we already know with countless examples (cane toads etc.) that people don't know what they're doing when they create an "ecosystem anew" (or - as what is really the case because of the fact that there is already an ecosystem on the island - messing with an existing ecosystem). I just wonder about unforeseen effects of introducing non-natives.
that is a whole different situation. Red wolves to the UK instead of grey wolves would be the equivalent of something like introducing harpy eagles to NZ to replace the Haast's eagle. Not even remotely similar to the Rotoroa Island project.LaughingDove said:Of course, the habitat on this island is going to be similar to the mainland so I don't the there will be (as many) unforeseen effects of introducing these species but if this idea was to extend further with species from somewhere completely different (such as - as was suggested on a different thread - the idea of introducing red wolves to the UK if wolves were to be introduced rather than grey wolves) then there could be huge effects that people didn't see coming at all.
y
the island's ecosystem has already been destroyed. It was a forested island which was turned into farmland. The project is restoring it to a forested island. They are replanting the trees, and most of the wildlife will have to be returned to the island by humans; very little would find its own way back.
not really. There are still extensive tracts of forest on the main islands, but they are ravaged by deer and possums, and the wildlife is destroyed by cats, rats, mustelids and wasps. What is extremely noticeable in NZ forests is the silence. The birds are almost all gone. Something foreign birders always comment on is how the first birds they see on arriving in NZ are invariably English species. I think NZ's post-human extinction level is second only to that of Hawaii. It is only on the offshore islands where you can get a sense of what NZ used to be like, and even there the ecosystems are missing half their components. Fortunately NZ has an abundance of offshore islands.DavidBrown said:Are there any substantial natural areas on the North or South Island that have retained their natural vegetation and wildlife intact? Obviously the removal of the moas and Haast's eagles have likely impacted some ecosystems in ways that no one can know.