It's funny how you see the same thread topics on different boards. On the Columbia river there's a big Sealion problem, Sealions eat returning Spring Chinook when the fish are congregated at the dams waiting to get upriver, considering about $400 million a year is spent on salmon and steelhead management on the Columbia, watching these expensive fish get gulped by Sealions is aggravating. The Marine Mammal protection act covers Sealions so they can't be lethally removed without Federal approval (they're working on it.)
There is also a problem with a predator known as the Northern Pikeminnow (formerly called Squawfish, name changed for PC reasons). Pikeminnow eat salmon and steelhead smolts, so the Feds came up with a program to PAY people to catch and kill Pikeminnow, it's a $3 per fish bounty. Top Pikeminnow fishermen make 30-40K per year catching Pikeminnow.