- 74 -of those is what we refer to as containment and I have an example at the top of the screen there. This was some work that I took part in South America two years ago, and there were invasive trees which had been planted around the town on this island, which were valuable to the local people. They would use the timber and so it was considered not appropriate to try and eradicate these trees. Instead, the decision was to contain them within the area which is shown by the red line on the right hand side of that island there. Another alternative is referred to as site-based control, and this is an approach where instead of trying to remove the target species across the entire island, certain priority areas are selected. These might be areas that provide habitat for the most critical species such as the Amami rabbit, frogs and spiny rats. But this approach has the disadvantage that control would then have to continue forever because there will be always be more cats able to move back into the control area from outside. And finally, another alternative is to create areas where native species can seek shelter from predators. And an example where this has been used successfully was in Mauritius, where an introduced monkey was preying on many species of endangered birds. They found that by planting a Japanese red cedar the birds were able to nest in this newly created habitat and suered much lower rates of predation from the monkeys.Slide18: Finally, of course, feral cats are not the only species on Amami that have the potential to kill the endangered native wildlife. One other example is feral dogs, and it’s important that these species are considered as well. So one possibility may be to use an approach which is quite commonly used in New Zealand where people’s dogs are actually taught to avoid Kiwi, which are an endangered native bird which is vulnerable to dog predation. So dogs are exposed to the smell of the Kiwi and they learn to associate that with an unpleasant stimulus. After that dogs will avoid contact with a real Kiwi in the wild. Another species which could potentially pose the problem on Amami is the black rat. There is a possibility that removal of cats could allow black rats to increase in number. So the solution to that problem may be to conduct rat control, perhaps using traps in areas where black rats occur. And nally, there is the possibility that removal of the cats could benett the mongoose population-or what is left of the mongoose population. And so it may be a good idea to wait until the last of the mongoose population has been removed before embarking on feral cat control.Slide19: So nally it’s important to think about what we are trying to achieve here. The aim is not simply to remove feral cats, the aim is to prevent the extinction of rare and precious fauna and to restore the ecosystems of Amami to a healthy functioning state. And most importantly of all the aim is to improve the social and economic wellbeing of the inhabitants of Amami. Slide20: Arigatou gozaimasu.
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