I don't know exactly where I heard it, but I'm pretty sure it was somewhere on felicifia.org.

I am somewhat skeptical of wild animal suffering being bad enough to necessitate nuking the rainforsts, but I think we should try to find out exactly how good their lives are. If their suffering really does significantly outweigh their happiness, then I don't see how we could justify not nuking them. If an animal is suffering and isn't likely to get better, you euthanize it. If this applies to all the animals, you euthanize all of them.