They make pretty good bear bait! All sorts of other predators as well. I'm not opposed to eating them out of clean water, if someone knows how to prepare them. But, I agree with the invasive species argument. If they didn't naturally occur in a particular ecosystem, I have no problems trying to protect that habitat. That's not just an excuse to kill something, that's the conservationist approach. I value all life, but believe their must be a balance. And if a species that people introduced, disrupts that balance, then people should return that balance to protect that ecosystem. If we allow a species that doesn't belong there to prosper, then the local species will suffer.