Based on what i got out of the book The Pacific Halibut The Fishery and The Resource which i browsed yesterday at my library, halibut were formerly an abundant fish in many places around Puget Sound but were promptly fished out upon discovery. It even so happens that the mouth of the Columbia a ways offshore even had a patch that got fished out in no time. Any halibut that are caught today are remnants of once sizeable populations. Author's last name was Bell if you wanna check it out.