There was a similar situation in Hawaii in the 80s. Introduced goats and sheep were destroying the food source (sole) of an ESA listed bird, the Palila. The bird actually was the plaintiff in a lawsuit against the State of Hawaii and it won. Under ESA the destruction of the habitat/food source was a take. Hawaii was ordered to remove the sheep. They didn't want to and drug their feet as the hunters opposed removal.

They have finally made significant inroads into the numbers, built exclusion fences, and improved the tree growth.

I think the only way the SRKW's get saved is a lawsuit shutting down the fisheries that are ahead of the whales (trailing fisheries are fine) and mandating the necessary habitat restoration. The State's and Fed's have, I believe, very little interest in actual restoration of SRKW or Chinook because it will require pi**ing off a lot of folks, whether it be AK fishermen (and their CongressCritters), Tribes, or lovers of brown-eyed mammals.