I'd say, as a general comment, that Washington state, particularly, and Oregon as well, have observed, as I noted in one of the remarks.... They have noted the problem with quite a bit of care, and they've taken on tackling the issue already.
There are examples, particularly in the Columbia River, where they went to either trapping or just removing. I'm not sure about the exact details of the removals. However, the evidence has already indicated a significant increase in steelhead recovery and passage by those natural “pinch points”, so called. They've also taken on different ways and means to consider how to work around the mammal act in the U.S., which is similar to the one that is in place for Canada. As I say, they initially took on a project to talk about discouraging the animals, and that didn't work. Then they moved on to the next level. Now they're at trapping and removal.
There are a number of examples, as I've mentioned, but they've taken on some tactics that seem to show quite of bit of success in addressing the issue.