Back in the 19th century, salmon fish traps brought in big hauls of Columbia River salmon. Retooled for the 21st century, could they be part of a more sustainable future for commercial harvests?  CATHLAMET, Wahkiakum County — More than eight decades after their demise, salmon fish traps are getting a fresh look from researchers convinced they offer a more sustainable way to catch Columbia River salmon. These traps are formed by nets attached to pilings that gently guide the fish into a kind of underwater corral. Wild fish protected under the federal Endangered Species Act can be released to...