Wolves are an important predator species that must be maintained to keep the balance of predator/prey in the wild. If there aren't enough wolves, prey species will proliferate, over-consume the resources they need to survive, and ultimately starve to death by the thousands. Keeping the predator/prey balance is much less cruel than letting the poor critters starve!
This legislation is designed to drive wolves to extinction, which would be utterly disastrous for the environment, to say the least. Without wolves, prey populations would skyrocket and destroy the area's plant life due to overgrazing. Wolves are vital to our ecosystem, and they require our protection.
I would, however, support legislation to re-issue federal guidelines removing walls from the Endangered Species Act protections in accordance with their designation as no longer in danger. The difference is significant. In one case, irreparable harm will be done to The endangered species act. In the case of reissuing guidelines, this removes federal court blockade of a decision already made to remove wolves from the endangered list.